U.S. patent application number 14/763004 was filed with the patent office on 2015-12-10 for ventricularly-anchored prosthetic valves.
The applicant listed for this patent is MITRALTECH LTD.. Invention is credited to Gil HACOHEN, Tal HAMMER, Yaron HERMAN, Natalia KRUGLOVA, Eran MILLER, Rotem NEEMAN, Tal REICH, Yuval ZIPORY.
Application Number | 20150351906 14/763004 |
Document ID | / |
Family ID | 50277269 |
Filed Date | 2015-12-10 |
United States Patent
Application |
20150351906 |
Kind Code |
A1 |
HAMMER; Tal ; et
al. |
December 10, 2015 |
VENTRICULARLY-ANCHORED PROSTHETIC VALVES
Abstract
Apparatus is provided, including: (A) a valve body (204)
including a first frame (206) shaped to define a lumen
therethrough, and a valve member (205) disposed within the lumen,
(B) an upstream support (210), configured to be placed against an
upstream surface of a native heart valve, and (C) a flexible sheet
(214) that couples the upstream support to the valve body. The
valve body has a compressed state in which the first frame has a
first diameter, and an expanded state in which the first frame has
a second diameter that is greater than the first diameter. The
support includes a second frame (212) that has a compressed state,
and an expanded state in which the second frame is annular, has an
inner perimeter that defines an opening through the second frame,
and has an outer perimeter. Other embodiments are also
described.
Inventors: |
HAMMER; Tal; (Ramat Gan,
IL) ; ZIPORY; Yuval; (Modi'in, IL) ; REICH;
Tal; (IL) ; HERMAN; Yaron; (Givat Ada, IL)
; HACOHEN; Gil; (Ramot HaShavim, IL) ; MILLER;
Eran; (Moshav Beit Elazari, IL) ; NEEMAN; Rotem;
(Yeshuv Nirit, IL) ; KRUGLOVA; Natalia; (Tel Aviv,
IL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
MITRALTECH LTD. |
Or Yehuda |
|
IL |
|
|
Family ID: |
50277269 |
Appl. No.: |
14/763004 |
Filed: |
January 23, 2014 |
PCT Filed: |
January 23, 2014 |
PCT NO: |
PCT/IL2014/050087 |
371 Date: |
July 23, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61756049 |
Jan 24, 2013 |
|
|
|
61756034 |
Jan 24, 2013 |
|
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Current U.S.
Class: |
623/2.11 ;
623/2.18 |
Current CPC
Class: |
A61F 2/2418 20130101;
A61F 2/2427 20130101; A61F 2220/0075 20130101; A61F 2/2436
20130101; A61F 2250/0098 20130101; A61F 2220/0016 20130101; A61F
2/2409 20130101; A61F 2220/0025 20130101 |
International
Class: |
A61F 2/24 20060101
A61F002/24 |
Claims
1. Apparatus for use with a native valve of a heart of a subject,
the apparatus comprising: a valve body: comprising (1) a first
frame shaped to define a lumen therethrough, and (2) a valve member
disposed within the lumen, having a compressed state in which the
first frame has a first diameter, and having an expanded state in
which the first frame has a second diameter that is greater than
the first diameter; an upstream support: configured to be placed
against an upstream surface of the native valve, comprising a
second frame, having a compressed state, and having an expanded
state in which the second frame is annular, has an inner perimeter
that defines an opening through the second frame, and has an outer
perimeter; and a flexible sheet that couples the upstream support
to the valve body.
2. The apparatus according to claim 1, wherein the upstream support
is coupled to the valve body only via the sheet.
3. The apparatus according to claim 1, wherein: the valve body has
an upstream end, a downstream end, and a longitudinal axis
therebetween along which the lumen is defined, and when the valve
body is in the expanded state thereof and the upstream support is
in the expanded state thereof: the first frame is attached to the
second frame at the inner perimeter of the second frame, and the
sheet is attached to the valve body and to the upstream support in
a manner that defines a pocket region between the sheet and at
least the inner perimeter of the second frame, the sheet not being
attached to the first frame or the second frame in the pocket
region.
4. The apparatus according to claim 1, wherein the sheet provides
fluid communication between the opening and the lumen.
5. The apparatus according to claim 1, wherein the sheet is not
attached to the inner perimeter of the second frame.
6. The apparatus according to claim 1, wherein the sheet is not
attached to an upstream end of the valve body.
7. The apparatus according to claim 1, wherein the sheet is
generally annular when the valve body is in the expanded state
thereof and the upstream support is in the expanded state
thereof.
8. The apparatus according to claim 1, wherein the sheet is
generally frustoconical when the valve body is in the expanded
state thereof and the upstream support is in the expanded state
thereof.
9. The apparatus according to claim 1, wherein the sheet is
attached to the inner perimeter of the second frame.
10. The apparatus according to claim 1, wherein the sheet is
circumferentially attached to the second frame at a radius that is
greater than a radius of the inner perimeter.
11. The apparatus according to claim 1, wherein the sheet is
circumferentially attached to the second frame at the outer
perimeter of the second frame.
12. The apparatus according to claim 1, wherein the sheet is
attached to an upstream end of the valve body.
13. The apparatus according to claim 1, wherein the first frame is
generally cylindrical in both the compressed state thereof and the
expanded state thereof.
14. The apparatus according to claim 1, wherein the second frame is
generally cylindrical in the compressed state thereof.
15. The apparatus according to any one of claims 1-14, wherein the
valve body comprises at least one downstream anchor, configured
such that, in the expanded configuration of the valve body, the
anchor protrudes radially outward from the first frame.
16. The apparatus according to claim 15, further comprising at
least one tensioning element, coupled to the valve body and to the
upstream support, a length of the tensioning element between the
valve body and the upstream portion being adjustable such that a
distance between the first frame and the second frame is
adjustable.
17. The apparatus according to claim 16, wherein the at least one
tensioning element comprises a tether.
18. The apparatus according to claim 16, wherein the at least one
tensioning element is coupled to the first frame, and slidably
coupled to the second frame.
19. The apparatus according to any one of claims 1-14, wherein the
valve body, the upstream support and the sheet together define a
prosthetic valve assembly, the prosthetic valve assembly: having an
expanded state in which the valve body is in the expanded state
thereof and the second frame of the upstream support is in the
expanded state thereof, having a compressed state in which: the
prosthetic valve assembly has a longitudinal axis, the valve body
is in the compressed state thereof at a first zone of the
longitudinal axis, the upstream support is in the compressed state
thereof at a second zone of the longitudinal axis, and the
prosthetic valve assembly defines an articulation zone, between the
first zone and the second zone, in which at least part of the sheet
is disposed, in which neither the first frame nor the second frame
is disposed, and about which the valve body and the upstream
support are articulatable with respect to each other.
20. The apparatus according to claim 19, further comprising a
delivery tool: comprising a first housing configured to house and
maintain at least part of the upstream support in the compressed
state thereof, and defining a first housing orifice through which
the at least part of the upstream support is removable from the
first housing, comprising a second housing configured to house and
maintain at least part of the valve body in the compressed state
thereof, and defining a second housing orifice through which the at
least part of the valve body is removable from the second housing,
having a contracted state in which the second housing is disposed
at a first distance from the first housing, and in which the
delivery tool is configured to transluminally advance the
prosthetic valve assembly in the compressed state thereof, to the
native valve, and having an extended state in which the second
housing is disposed at a second distance from the first housing,
the second distance being greater than the first distance, wherein
the apparatus is configured such that, when the at least part of
the upstream support is housed by the first housing and the at
least part of the valve body is housed by the second housing,
transitioning of the delivery tool from the contracted state into
the extended state exposes at least part of at least one component
selected from the group consisting of: the valve body and the
upstream support, from the housing that houses the selected
component.
21. The apparatus according to claim 20, wherein: the apparatus is
configured to be used with at least two guide members, the
prosthetic valve assembly comprises at least two eyelets, each
eyelet being slidable over a respective one of the guide members,
and the apparatus is configured such that the eyelets of the
prosthetic valve assembly protrude radially outward and radially
beyond an outer surface of the second housing while: (1) the at
least part of the valve body, in the compressed state thereof, is
housed by the second housing, and (2) the at least part of the
upstream support, in the compressed state thereof, is housed by the
first housing.
22. The apparatus according to claim 21, wherein the eyelets are
pivotably coupled to the valve body.
23. The apparatus according to claim 21, wherein the delivery tool
further comprises at least two reference-force tubes, each
reference-force tube configured (1) to be slidable over a
respective one of the guide members, and (2) to apply a
distally-directed force to the prosthetic valve assembly.
24. The apparatus according to claim 23, wherein, in the compressed
state of the prosthetic valve assembly, each reference-force tube
extends distally (1) through a lumen defined by the second frame of
the upstream support, (2) through the sheet, and (3) along an
outside of at least part of the valve body.
25. The apparatus according to claim 21, further comprising at
least two locking members, each locking member: having an unlocked
state in which the locking member is slidable along a respective
one of the guide members, being transitionable into a locked state
in which (1) the locking member is locked to the respective one of
the guide members, and (2) the sliding of the eyelet over the guide
member is inhibited.
26. The apparatus according to claim 25, further comprising the at
least two guide members, wherein: each guide member comprises: a
tubular member, shaped to define a lumen therethrough, a tether,
coupled at a distal end thereof to a tissue anchor configured to be
anchored to ventricular tissue of the heart, at least a proximal
portion of the tether being disposed within the lumen of the
tubular member, and a pull-wire, coupled at a distal portion
thereof to the proximal portion of the tether, at least the distal
portion of the pull-wire being disposed within the lumen of the
tubular member, the tubular member inhibits decoupling of the
pull-wire from the tether while the distal portion of the pull-wire
and the proximal portion of the tether are disposed within the
lumen of the tubular member, and while the tubular member of each
guide member is disposed within the respective locking member, the
tubular member inhibits transitioning of the locking member into
the locked state.
27. The apparatus according to claim 26, wherein the apparatus is
configured such that, for each respective guide member and locking
member, while (1) the tubular member is disposed within the locking
member, (2) the distal portion of the pull-wire and the proximal
portion of the tether are disposed within the lumen of the tubular
member, and (3) the tissue anchor is coupled to the ventricular
tissue: proximal sliding of the tubular member with respect to the
tether facilitates automatic transitioning of the locking member
into the locked state, and further proximal sliding of the tubular
member with respect to the tether facilitates decoupling of the
pull-wire from the tether.
28. The apparatus according to claim 21, wherein at least one
housing selected from the group consisting of: the first housing
and the second housing has a lateral wall that is shaped to define
at least two slits, the eyelets being configured to protrude
radially outward from the delivery tool via the slits.
29. The apparatus according to claim 28, wherein each slit of the
at least one selected housing is continuous with the orifice of the
at least one selected housing.
30. The apparatus according to claim 21, wherein the eyelets are
coupled to and protrude radially outward from the valve body.
31. The apparatus according to claim 30, wherein the eyelets are
pivotably coupled to the valve body.
32. The apparatus according to claim 20, wherein: the articulation
zone defined by the prosthetic valve assembly comprises a first
articulation zone, and while (1) the at least part of the valve
body, in the compressed state thereof, is housed by the second
housing, (2) the at least part of the upstream support, in the
compressed state thereof, is housed by the first housing, and (3)
the delivery tool is in the contracted state thereof, the apparatus
defines a second articulation zone at a longitudinal zone of the
apparatus (a) between the second housing and the first housing, and
(b) in which is disposed at least part of the first articulation
zone.
33. The apparatus according to claim 32, wherein the delivery tool
further comprises a housing-control rod that extends through the
first housing and is coupled to the second housing such that a
first portion of the housing-control rod is disposed within the
first housing, a second portion of the housing-control rod is
disposed within the second housing, and a third portion of the
housing-control rod (1) is disposed within the second articulation
zone, and (2) is more flexible than at least one portion of the
housing-control rod selected from the group consisting of: the
first portion and the second portion.
34. The apparatus according to claim 32, wherein: the delivery tool
further comprises (1) a control rod assembly comprising at least a
first housing-control rod coupled to the first housing, and (2) a
second housing-control rod, more flexible than the first
housing-control rod, extending through the first housing-control
rod, extending through the second articulation zone, and coupled to
the second housing.
35. The apparatus according to claim 20, wherein the second housing
orifice faces the first housing orifice.
36. The apparatus according to claim 20, wherein: the delivery tool
further comprises a flexible control rod assembly comprising (1) a
first housing-control rod coupled to the first housing, (2) a
second housing-control rod coupled to the second housing, and (3) a
prosthesis-control rod reversibly couplable to the prosthetic valve
assembly, longitudinal movement of the second housing-control rod
with respect to the first housing-control rod transitions the
delivery tool between the contracted state and the extended state
thereof, and the valve body is removable from the second housing by
moving the second housing-control rod with respect to the
prosthesis-control rod.
37. The apparatus according to claim 36, wherein the
prosthesis-control rod is reversibly couplable to the prosthetic
valve assembly by being reversibly couplable to the valve body.
38. The apparatus according to claim 36, wherein at least part of
the second housing-control rod is disposed within and slidable
through the prosthesis-control rod, and at least part of the
prosthesis-control rod is disposed within and slidable through the
first housing-control rod.
39. The apparatus according to any one of claims 1-14, wherein the
outer perimeter of the second frame has a third diameter that is
greater than the second diameter.
40. The apparatus according to claim 39, wherein the inner
perimeter has a fourth diameter that is greater than the second
diameter.
41. The apparatus according to any one of claims 1-14, wherein,
when the valve body is in the expanded state thereof and the
upstream support is in the expanded state thereof, a gap is defined
between the first frame and the second frame, the sheet spanning
the gap.
42. The apparatus according to claim 41, wherein no metallic
structure is disposed within the gap.
43. The apparatus according to any one of claims 1-14, wherein the
sheet is configured to inhibit expansion of the second frame.
44. The apparatus according to claim 43, wherein the apparatus is
configured such that when the second frame expands from the
compressed state thereof toward the expanded state thereof, the
sheet retains the second frame in a generally frustoconical shape
by inhibiting expansion of at least the outer perimeter of the
second frame.
45. The apparatus according to any one of claims 1-14, wherein the
sheet extends over at least part of the second frame to serve as a
covering of the upstream support.
46. The apparatus according to claim 45, wherein the covering
defines a tissue-contacting surface of the upstream support.
47. The apparatus according to any one of claims 1-14, wherein the
sheet extends over at least part of the first frame to serve as a
covering of the valve body.
48. The apparatus according to claim 47, wherein the covering is
disposed on an inner surface of the first frame.
49. Apparatus for use with a native valve of a heart of a subject,
the apparatus comprising: a prosthetic valve, configured to be
percutaneously delivered to the native valve; an annular upstream
support, configured to be placed against an upstream surface of the
native valve, and to support the prosthetic valve at the native
valve; a tissue anchor, comprising a tissue-engaging element
configured to be anchored to ventricular muscle tissue of the
heart; a tether, coupled to the tissue anchor; and a spring,
couplable to the tether so as to elastically couple the
tissue-engaging element to the prosthetic valve.
50. The apparatus according to claim 49, wherein the spring is
shaped to define a repeating pattern.
51. The apparatus according to claim 49, wherein the spring is
pre-loaded.
52. The apparatus according to claim 49, wherein the spring is a
constant-force spring.
53. The apparatus according to any one of claims 49-52, wherein the
spring is configured to facilitate extracorporeal fluoroscopic
observation of a state of the spring.
54. The apparatus according to claim 53, wherein the spring is
coupled to a plurality of radiopaque markers such that a
juxtaposition of the markers changes as the state of the spring
changes, the juxtaposition of the markers being extracorporeally
fluoroscopically observable.
55. The apparatus according to claim 53, wherein the spring is
coupled to at least one radiopaque marker, and the apparatus
further comprises an intracorporeal reference, a juxtaposition
between the radiopaque marker and the intracorporeal reference
being extracorporeally fluoroscopically observable.
56. The apparatus according to claim 55, wherein the intracorporeal
reference comprises a scale comprising a plurality of radiopaque
markers.
57. The apparatus according to claim 56, wherein the plurality of
radiopaque markers comprises a first plurality of radiopaque
markers, and the at least one radiopaque marker comprises a second
plurality of radiopaque markers.
58. The apparatus according to claim 53, wherein the spring is
configured to provide distinct indication that is observable using
fluoroscopy, when the spring is experiencing a force that is within
a margin force from a target force.
59. The apparatus according to claim 58, wherein the spring is
configured to provide the distinct indication when the spring
experiences a force that is above 300 g force.
60. The apparatus according to claim 59, wherein the spring is
configured to provide the distinct indication when the spring
experiences a force that is above 400 g force.
61. The apparatus according to claim 60, wherein the spring is
configured to provide the distinct indication when the spring
experiences a force that is about 500 g force.
62. The apparatus according to any one of claims 49-52, wherein the
spring is coupled to the prosthetic valve, and is intracorporeally
lockable to the tether subsequently to anchoring of the tissue
anchor to the ventricular muscle tissue.
63. The apparatus according to claim 62, wherein the spring is
slidable along at least part of the tether, and is intracorporeally
couplable to the tether by inhibiting the sliding.
64. The apparatus according to claim 62, wherein the prosthetic
valve comprises a generally cylindrical valve body having an
upstream end, and the spring comprises an elastically-deformable
appendage that protrudes laterally from the valve body.
65. The apparatus according to claim 62, wherein: the prosthetic
valve comprises a generally cylindrical valve body having an
upstream end, a downstream end, and a longitudinal lumen
therebetween, and the spring (1) comprises a compression spring
having a longitudinal axis, and (2) is disposed laterally from, the
valve body such that the longitudinal axis of the spring is
generally parallel with the longitudinal lumen.
66. The apparatus according to any one of claims 49-52, wherein the
prosthetic valve comprises: a generally cylindrical valve body
having an upstream end, a downstream end, and a longitudinal lumen
therebetween; and one or more tissue-engaging legs, protruding
laterally outward from the valve body, and configured to be placed
against a ventricular surface of the native valve.
67. The apparatus according to claim 66, wherein the prosthetic
valve is couplable to the upstream support intracorporeally by
being expanded within an opening defined by the upstream support
while the upstream support is disposed against the upstream
surface.
68. The apparatus according to claim 67, wherein the apparatus is
configured such that the coupling of the prosthetic valve to the
upstream support couples the tether to the prosthetic valve.
69. The apparatus according to claim 67, wherein the apparatus is
configured to sandwich a portion of the native valve between the
tissue-engaging legs and the upstream support by providing a space
having a height between the tissue-engaging legs and the upstream
support.
70. The apparatus according to claim 69, wherein the apparatus is
configured to facilitate altering the height without altering a
force on the spring.
71. The apparatus according to claim 69, wherein the apparatus is
configured such that altering the height automatically alters a
force on the spring.
72. The apparatus according to claim 69, wherein the apparatus is
configured to facilitate altering the height by moving the valve
body through the opening defined by the upstream support.
73. Apparatus for use with a native heart valve of a subject, the
apparatus comprising: a valve body: having an upstream end, a
downstream end, and a longitudinal axis therebetween, comprising a
lateral wall that circumscribes the longitudinal axis and defines a
longitudinal lumen, and comprising a valve member disposed within
the lumen; an upstream support having an inner perimeter couplable
to the valve body at a first longitudinal position of the valve
body, the upstream support being configured to extend radially
outward from the valve body and the inner perimeter; and a flexible
sheet defining a first aperture, a second aperture and a lateral
wall therebetween, a first portion of the sheet that defines the
first aperture being circumferentially attached to the upstream
support portion at a radius that is greater than a radius of the
inner perimeter, and a second portion of the sheet that defines the
second aperture being circumferentially attached to the valve body
at a second longitudinal position of the valve body, such that a
pocket region is defined between the sheet and at least the first
longitudinal position.
74. The apparatus according to claim 73, wherein the second
longitudinal position is closer to the downstream end of the valve
body than is the first longitudinal position.
75. The apparatus according to claim 73, wherein the first aperture
is larger than the second aperture.
76. The apparatus according to claim 73, wherein the sheet is
attached to the upstream support at an outer perimeter of the
upstream support.
77. The apparatus according to claim 73, wherein the sheet assumes
a frustoconical shape.
78. The apparatus according to claim 73, wherein the sheet assumes
a funnel shape.
79. The apparatus according to claim 73, wherein the apparatus is
provided with the inner perimeter of the upstream support
pre-coupled to the valve body at the first longitudinal position of
the valve body.
80. The apparatus according to any one of claims 73-79, wherein the
apparatus is configured such that the inner perimeter of the
upstream support is intracorporeally couplable to the valve body at
the first longitudinal position of the valve body.
81. Apparatus for use with a native heart valve disposed between an
atrium and a ventricle of a heart of a subject, the apparatus
comprising: an annular upstream support defining an opening
therethrough, and configured to be placed against an upstream
surface of the native heart valve; a tubular valve body having an
upstream end, a downstream end and a lumen therebetween, the lumen
having a first diameter, and the valve body being separated from
the upstream element by a gap between the upstream end of the valve
body and the upstream element; one or more tissue-engaging elements
that protrude radially outward from the valve body so as to define
a second diameter that is greater than the first diameter; and a
flexible sheet shaped to define a conduit, a downstream portion of
the sheet being coupled to the valve body, an upstream portion of
the sheet being coupled to the upstream element, and the sheet
spanning the gap.
82. The apparatus according to claim 81, further comprising at
least one tether, a first portion of the tether being coupled to
the valve body and a second portion of the tether being coupled to
the upstream support, such that tensioning of at least a portion of
the tether reduces the gap.
83. The apparatus according to claim 82, wherein the apparatus is
configured such that tensioning of at least the portion of the
tether rumples the sheet.
84. Apparatus for use with a native heart valve disposed between an
atrium and a ventricle of a heart of a subject, the apparatus
comprising: an annular upstream element defining an opening
therethrough, and configured to be placed against an upstream
surface of the native heart valve; a flexible sheet, shaped to
define a conduit, and coupled to the upstream element such that the
conduit is in fluid communication with the opening; and a valve
body, coupled to the flexible sheet such that the conduit provides
fluid communication between the prosthetic valve and the upstream
element.
85. The apparatus according to claim 84, wherein the valve body
comprises: a generally cylindrical frame shaped to define a lumen
therethrough, and a valve member coupled to the frame and disposed
within the lumen.
86. The apparatus according to any one of claims 84-85, wherein the
frame is separated from the upstream element by a gap, and the
conduit spans the gap.
87. Apparatus, for use with a guide member that extends into a
subject, the apparatus comprising: a delivery tool, comprising a
housing, the housing: being transluminally advanceable into the
subject, shaped to define an orifice at an end of the housing, and
having a lateral wall shaped to define a slit that is continuous
with the orifice; an implant: configured to be housed by the
housing, and comprising an eyelet that (1) is slidable over the
guide member, and (2) when the implant is housed by the housing,
extends through the slit and radially beyond the lateral wall such
that the eyelet facilitates transluminal sliding of the implant and
the housing along the guide member and into the subject, the
apparatus being configured such that, while (1) the implant remains
within the subject, and (2) the guide member remains disposed
through the eyelet, (1) the implant is removable from the housing
via the orifice, and (2) the housing is removable from the
subject.
88. The apparatus according to claim 87, wherein the implant is
configured to be implanted by being intracorporeally locked to the
guide member.
89. The apparatus according to any one of claims 87-88, wherein the
implant has a compressed state and an expanded state, is configured
to be housed by the housing while in the compressed state, and is
configured to automatically expand toward the expanded state when
removed from the housing.
90. A method for use with a native valve of a heart of a subject,
the method comprising: transluminally anchoring a tissue anchor to
ventricular tissue of a subject using an anchor-manipulation tool,
the tissue anchor being coupled to a first portion of a tether;
transluminally delivering an annular upstream support and a
prosthetic valve to the heart, the prosthetic valve including (1) a
valve body shaped to define a lumen therethrough, and (2) one or
more tissue-engaging legs configured to protrude laterally outward
from the valve body; pressing the tissue-engaging legs in an
upstream direction against a ventricular surface of the native
valve by applying a force to the prosthetic valve while measuring
the force; applying, to the tether, a tension that changes a shape
of a spring coupled to the tether, while observing the shape of the
spring using imaging; and at least in part responsively to the
observed shape of the spring, facilitating holding of the upstream
support against an upstream surface of the native valve by locking
a second portion of the tether to at least one component selected
from the group consisting of: the prosthetic valve and the upstream
support.
91. The method according to claim 90, wherein measuring the force
comprises measuring the force using an extracorporeal force
meter.
92. The method according to claim 90, wherein measuring the force
comprises observing a shape of the tissue-engaging legs using
imaging.
93. The method according to claim 90, wherein applying the tension
comprises applying the tension while applying the force.
94. The method according to claim 90, wherein locking the second
portion to the selected component comprises locking the second
portion to the prosthetic valve.
95. The method according to claim 90, wherein locking the second
portion to the selected component comprises locking the second
portion to the upstream support.
96. The method according to claim 90, wherein locking the second
portion comprises locking the second portion when the observed
shape indicates that the spring is experiencing between 400 g force
and 600 g force.
97. The method according to claim 90, wherein locking the second
portion comprises locking the second portion subsequently to
applying the tension, and applying the force comprises applying the
force subsequently to locking the second portion.
98. The method according to any one of claims 90-97, wherein:
anchoring the tissue anchor coupled to the tether comprises
anchoring a first tissue anchor coupled to a first tether, and
applying the tension comprises applying a first tension that
changes a shape of a first spring coupled to the first tether, the
method further comprises: anchoring a second tissue anchor to the
ventricular tissue, the second tissue anchor being coupled to a
first portion of a second tether; and applying, to the second
tether, a second tension that changes a shape of a second spring
coupled to the second tether, while observing the shape of the
second spring using imaging, and facilitating holding of the
prosthetic valve against the upstream surface comprises, at least
in part responsively to the observed shape of the second spring,
facilitating holding of the prosthetic valve against the upstream
surface by locking a second portion of the second tether to the
selected at least one component.
99. The method according to claim 98, wherein facilitating holding
comprises locking the second portion of the first tether and the
second portion of the second tether to the selected at least one
component, at least in part responsively to a ratio between tension
in the first tether and tension in the second tether, the ratio
being derived from the observed shape of the first spring and the
observed shape of the second spring.
100. The method according to any one of claims 90-97, wherein
locking comprises locking the second portion to the at least one
component at least in part responsively to the observed shape.
101. The method according to claim 100, wherein locking comprises
locking the second portion to the at least one component at least
in part responsively to the measured force.
102. The method according to any one of claims 90-97, wherein
applying the force comprises moving the valve body in an upstream
direction through an opening defined by the upstream support, and
the method further comprises coupling the prosthetic valve to the
upstream support by expanding the valve body within the
opening.
103. The method according to claim 102, wherein coupling the
prosthetic valve to the upstream support comprises coupling the
prosthetic valve to the upstream support at least in part
responsively to the measured force.
104. A method, comprising: transluminally advancing a plurality of
tissue anchors, coupled to a respective plurality of springs, into
a body of a subject; anchoring the plurality of tissue anchors to
tissue of the subject; tensioning at least one of the springs;
using imaging, while the tension is applied to the at least one
spring, observing a state of the at least one spring; and at least
in part responsively to the observed state of at least one spring,
adjusting a tension on at least one of the springs.
105. A method, for use with a native valve of a heart of a subject,
the method comprising: applying a first tension to a tether that
couples (a) a tissue anchor anchored to ventricular tissue of a
subject, to (b) a prosthetic valve body, the tether having a length
between the tissue anchor and the valve body; by applying an
atrially-directed force to the prosthetic valve body, pressing,
against tissue of the native valve, a tissue-engaging element that
protrudes radially from the valve body transluminally advancing a
prosthetic valve body to a native valve of the subject; while
applying the atrially-directed force, measuring: a pressing force
of the tissue-engaging element against the tissue of the native
valve, and a second tension on the tether, the second tension
differing from the first tension at least in part due to the
atrially-directed force; and at least in part responsively to the
measured pressing force and the measured second tension, performing
an action selected from the group consisting of: adjusting the
length of the tether between the tissue anchor and the valve body,
and locking the valve body to the tether.
106. A method for use with a native valve of a heart of a subject,
the method comprising: transluminally delivering a tissue anchor to
a ventricle of the heart, and anchoring the tissue anchor to
ventricular muscle tissue of the subject; transluminally delivering
an upstream support to an atrium of the heart, and placing the
upstream support against an upstream surface of an annulus of the
native valve; and changing a shape of the upstream support by
tensioning a tether coupled to upstream support and to the tissue
anchor; and extracorporeally fluoroscopically observing the shape
change of the upstream support.
107. The method according to claim 106, wherein tensioning the
tether coupled to the upstream support comprises tensioning a
tether that is coupled to a valve body coupled to the upstream
support.
108. The method according to claim 106, wherein, before the
tensioning, the upstream support is generally flat annular, and
changing the shape comprises making the support assume a
frustoconical shape.
109. The method according to any one of claims 106-108, wherein,
before the tensioning, the upstream support is frustoconical, and
changing the shape comprises changing a slant of the frustoconical
shape.
110. Apparatus for use with a valve of a heart of a subject, the
apparatus comprising: a transluminally-deliverable tissue anchor; a
tether, a first end thereof coupled to the tissue anchor; and a
delivery tool, comprising: a steerable catheter having a
longitudinal axis, and being transluminally deliverable to the
valve, and an obstructing element: disposed at a longitudinal site
of the catheter, configured to extend laterally outward from the
catheter, and dimensioned, when extending laterally outward from
the catheter, to inhibit movement of at least the longitudinal site
through the valve by abutting tissue of the valve, and an anchor
manipulator: reversibly couplable to the tissue anchor, slidable
through the catheter, and configured to drive the anchor into
ventricular tissue of the heart of the subject.
111. The apparatus according to claim 110, wherein the anchor
manipulator is slidably coupled to the catheter such that a distal
end of the anchor manipulator is slidable distally no more than a
pre-determined distance from the longitudinal site.
112. The apparatus according to any one of claims 110-111, further
comprising an implant, intracorporeally lockable to the tether.
113. The apparatus according to claim 112, further comprising a
guide member, reversibly couplable to the tether, wherein the
implant is intracorporeally slidable along the guide member toward
the tether and the implant.
114. The apparatus according to claim 112, wherein the tether has
exactly one locking site at which the implant is lockable to the
tether.
115. The apparatus according to claim 114, wherein the exactly one
locking site is disposed at a pre-determined distance from the
anchor that is pre-determined at least in part dependently on a
distance between the longitudinal site and a distal end of the
catheter.
116. A method, comprising: transluminally anchoring a tissue anchor
to tissue of a subject using an anchor-manipulation tool;
subsequently applying to the anchor a pulling force having a given
magnitude; using imaging, observing a movement of the tissue anchor
in response to the pulling force; and at least in part responsively
to the observed movement, performing an action selected from the
group consisting of: de-anchoring the tissue anchor from the
tissue, and decoupling the anchor-manipulation tool from the tissue
anchor.
117. Apparatus, for implantation at a native valve of a heart of a
subject, the native valve being disposed between an atrium and a
ventricle of the heart, the apparatus comprising: a tubular valve
body: having an upstream portion, configured to be disposed in the
atrium of the heart of the subject, having a downstream portion,
configured to be disposed in the ventricle of the subject, having
an elastic portion, disposed between the upstream portion and the
downstream portion, and elastically coupling the upstream portion
to the downstream portion, and shaped to define a continuous lumen
through the upstream portion, the elastic portion, and the
downstream portion; and at least one valve member, disposed in the
lumen of the valve body, and configured to facilitate flow of blood
of the subject from the upstream portion of the valve body to the
downstream portion of the valve body, and to inhibit flow of the
blood from the downstream portion of the valve body to the upstream
portion of the valve body.
118. The apparatus according to claim 117, wherein the at least one
valve member is coupled to the downstream portion of the valve
body.
119. The apparatus according to claim 117, wherein the native valve
includes a plurality of native leaflets, and wherein the downstream
portion of the valve body is configured to be coupled to the native
leaflets.
120. The apparatus according to claim 119, further comprising a
plurality of clips, configured to facilitate the coupling of the
downstream portion of the valve body to the native leaflets.
121. The apparatus according to claim 120, wherein each clip:
comprises at least two clip arms, articulatably coupled to each
other, and is reversibly closeable.
122. The apparatus according to claim 120, wherein the clips are
coupled to the downstream portion of the valve body, and wherein
the downstream portion of the valve body is configured to be
coupled to the native leaflets by the clips being coupled to the
native leaflets.
123. The apparatus according to claim 120, wherein each clip of the
plurality of clips is articulatably coupled to the downstream
portion of the valve body.
124. The apparatus according to claim 120, the native valve
including an annulus having an upstream surface, wherein the
apparatus further comprises a prosthetic valve support: comprising
(1) an upstream support portion, configured to be placed against
the upstream surface of the annulus of the native valve, and (2)
the plurality of clips, coupled to the upstream support portion,
shaped to define an opening therethrough that is configured to
receive the prosthetic valve, wherein the clips are configured to
facilitate the coupling of the downstream portion of the valve body
to the native leaflets by coupling the prosthetic valve support to
the native leaflets.
125. Apparatus for use with a native valve of a heart of a subject,
the native valve having a plurality of leaflets that meet at a
plurality of commissures, the apparatus comprising: at least one
tissue anchor, configured to be anchored to a first site within a
ventricle of the heart of the subject; at least one longitudinal
member, coupled at a distal end thereof to a respective one of the
at least one tissue anchors; an upstream support, comprising an
upstream support portion configured to be slidable over the
longitudinal member and placed against an upstream surface of the
native valve; and at least one locking member, configured to be
slidable over a respective one of the at least one longitudinal
members, and to be lockable to the respective longitudinal member
such that a portion of the respective longitudinal member that is
disposed between the respective anchor and the upstream support
portion is longer than 1 cm.
126. The apparatus according to claim 125, wherein the longitudinal
member is flexible.
127. The apparatus according to any one of claims 125-126, wherein
the longitudinal member comprises a suture.
128. A method for use with a native valve of a heart of a subject,
the native valve having a plurality of leaflets that meet at a
first commissure and at a second commissure, the method comprising:
anchoring a first tissue anchor to a first site within a ventricle
of the heart of the subject, the first tissue anchor being coupled
to a distal end of a first longitudinal member; anchoring a second
tissue anchor to a second site within the ventricle of the heart of
the subject, the second tissue anchor being coupled to a distal end
of a second longitudinal member; subsequently, placing at least an
upstream support portion of a prosthetic valve support against an
upstream surface of the native valve, the valve being disposed
between the ventricle and an atrium of the heart of the subject;
and securing the upstream support portion against the upstream
surface of the valve by: coupling the upstream support portion to
the first longitudinal member such that at least part of a portion
of the first longitudinal member that is disposed between the
upstream support portion and the first tissue anchor, is disposed
between the first and second leaflets at the first commissure, and
coupling the upstream support portion to the second longitudinal
member such that at least part of a portion of the second
longitudinal member that is disposed between the upstream support
portion and the first tissue anchor, is disposed between the first
and second leaflets at the second commissure.
129. The method according to claim 128, wherein anchoring, placing,
and securing comprise anchoring, securing, and placing without the
use of cardiopulmonary bypass.
130. The method according to claim 128, wherein anchoring to the
first site and anchoring to the second site comprise anchoring to
myocardium.
131. The method according to claim 128, wherein placing the
upstream support portion against the upstream surface comprises
sliding the upstream support portion over at least part of the
first longitudinal member.
132. The method according to claim 128, wherein coupling the
upstream support portion to the first longitudinal member and to
the second longitudinal member comprises coupling the upstream
support portion to the first longitudinal member in the atrium of
the heart of the subject, and coupling the upstream support portion
to the second longitudinal member comprises coupling the upstream
support portion to the second longitudinal member in the atrium of
the heart of the subject.
133. The method according to claim 128, wherein the leaflets move
in response to beating of the heart of the subject, and wherein
securing the upstream support portion comprises securing the
upstream support portion without eliminating the movement of the
native leaflets.
134. The method according to claim 128, wherein coupling the
upstream support portion to the first longitudinal member comprises
coupling the upstream support portion to the first longitudinal
member such that a length of the portion of the first longitudinal
member is greater than 1 cm.
135. The method according to any one of claims 128-134, further
comprising: transluminally advancing at least the first tissue
anchor to the first site while the respective longitudinal member
coupled thereto is disposed within a respective tubular member; and
subsequently to anchoring the at least first tissue anchor, and
before coupling the upstream support portion to the respective
longitudinal member, sliding the at least first tubular member off
of at least part of the respective longitudinal member.
136. The method according to claim 135, wherein sliding the at
least first tubular member comprises sliding at least part of the
at least first tubular member through a channel defined by a
locking member, and wherein coupling the upstream support portion
to the respective longitudinal member comprises locking the locking
member to the respective longitudinal member by narrowing at least
a portion of the channel.
137. The method according to any one of claims 128-134, wherein:
advancing the at least first tissue anchor comprises advancing the
at least first tissue anchor while (1) the respective longitudinal
member is reversibly coupled to a portion of a wire, and (2) the
respective tubular member inhibits the portion of the wire from
decoupling from the portion of the wire, and the method further
comprises facilitating decoupling of the wire from the respective
longitudinal member by sliding the at least first tubular member
off of the portion of the wire.
138. The method according to claim 137, wherein: advancing the at
least first tissue anchor comprises advancing the at least first
tissue anchor while (1) the respective longitudinal member is
shaped to define a loop, and is coupled to the portion of the wire
by the portion of the wire being threaded through the loop, and (2)
the respective tubular member inhibits the portion of the wire from
unthreading from the loop, and facilitating decoupling of the wire
from the respective longitudinal member comprises facilitating
unthreading of the wire from the loop by sliding the at least first
tubular member off of the portion of the wire.
139. The method according to claim 138, wherein sliding the at
least first tubular member off of the portion of the wire comprises
sliding the at least first tubular member off of the portion of the
wire by applying less than 500 g of pulling force to the at least
first tubular member.
140. The method according to claim 139, wherein applying less than
500 g of pulling force to the at least first tubular member
comprises applying less than 300 g of pulling force to the at least
first tubular member.
141. The method according to any one of claims 128-134, further
comprising, subsequently to securing the upstream support portion,
coupling a prosthetic valve to the prosthetic valve support.
142. The method according to claim 141, wherein the upstream
support portion has an inner edge that defines an opening through
the upstream support portion, and wherein coupling the prosthetic
valve to the prosthetic valve support comprises placing at least a
portion of the prosthetic valve within the opening, and expanding
at least the portion of the prosthetic valve such that at least the
portion of the prosthetic valve applies a radially-expansive force
against the inner edge of the upstream support portion.
143. The method according to claim 141, wherein the prosthetic
valve includes one or more tissue-engaging elements, each of the
one or more tissue-engaging elements including at least two arms,
and wherein the method further comprises, subsequent to securing
the upstream support portion, coupling the prosthetic valve to at
least one of the leaflets by sandwiching the at least one of the
leaflets between the at least clip arms of the one or more
tissue-engaging elements.
144. The method according to claim 143, wherein coupling the
prosthetic valve to the at least one of the leaflets comprises
coupling the prosthetic valve to the at least one of the leaflets
before coupling the prosthetic valve to the prosthetic valve
support.
145. The method according to claim 143, wherein: the prosthetic
valve includes a valve body, having an outer surface, the at least
two arms include a first arm and a second arm, the first arm being
longer than the second arm, and the method further comprises:
delivering, within a delivery tube, the prosthetic valve in a
delivery configuration thereof, in which the first arm and the
second arm are constrained against the outer surface of the valve
body; facilitating deflection of the first arm away from the outer
surface of the prosthetic valve, by advancing a first portion of
the prosthetic valve out of the delivery tube such that the first
arm automatically deflects away from the outer surface of the
prosthetic valve; and facilitating deflection of the second arm
away from the outer surface of the prosthetic valve, by advancing a
second portion of the prosthetic valve out of the delivery tube
such that the second arm automatically deflects away from the outer
surface of the prosthetic valve.
146. The method according to claim 145, wherein: facilitating
deflection of the first arm comprises facilitating deflection of
the first arm a first angle from the outer surface of the
prosthetic valve, and the method further comprises facilitating
deflection of the first arm away from the outer surface of the
prosthetic valve a second angle that is greater than the first
angle, by applying a force to the first arm using the delivery
tube: subsequently to facilitating deflection of the first arm the
first angle, and prior to facilitating deflection of the second
arm.
147. The method according to claim 146, wherein applying the force
to the first arm using the delivery tube comprises pushing on the
first arm by sliding the delivery tube over at least part of the
prosthetic valve.
148. Apparatus for use with a body of a subject, the apparatus
comprising: at least a first implantable member; a first
longitudinal member, coupled at a distal end thereof to the first
implantable member; a second longitudinal member, at least a
portion of the second longitudinal member being reversibly
couplable to the first longitudinal member; and a tubular member:
slidable over the first and second longitudinal members, shaped to
define a lumen therethrough, and configured, when the portion of
the second longitudinal member is (1) coupled to the first
longitudinal member, and (2) disposed within the lumen of the
tubular member, to inhibit decoupling of the portion of the second
longitudinal member from the first longitudinal member.
149. The apparatus according to claim 148, wherein the portion of
the second longitudinal member is configured, when (1) the portion
of the second longitudinal member is coupled to the first
longitudinal member, and (2) the portion of the second longitudinal
member is disposed outside of the lumen of the tubular member, to
be decouplable from the first longitudinal member by the second
longitudinal member being pulled away from the first longitudinal
member.
150. The apparatus according to claim 148, wherein at least one
longitudinal member selected from the group consisting of: the
first longitudinal member and the second longitudinal member, is
flexible.
151. The apparatus according to claim 148, wherein the tubular
member is more rigid than the first longitudinal member.
152. The apparatus according to claim 148, wherein the tubular
member fits snugly over at least the portion of the second
longitudinal member.
153. The apparatus according to claim 148, wherein the first
implantable member comprises a tissue anchor, configured to be
anchored to a tissue of the subject.
154. The apparatus according to any one of claims 148-153, further
comprising a second implantable member, slidable over the tubular
member, and couplable to the first longitudinal member while the
portion of the second longitudinal member is coupled to the first
longitudinal member.
155. The apparatus according to claim 154, wherein the portion of
the second longitudinal member is reversibly couplable to the first
longitudinal member at a first site of the first longitudinal
member, and wherein the second implantable member is couplable to
the first longitudinal member at a second site of the first
longitudinal member that is distal to the first site of the
longitudinal member.
156. The apparatus according to claim 154, further comprising a
locking member having an unlocked state and a locked state, and
configured to be slid over the tubular member in the unlocked state
and to be locked to the first longitudinal member by being
transitioned to the locked state.
157. The apparatus according to claim 156, wherein the locking
member is configured to facilitate coupling of the second
implantable member to the first longitudinal member.
158. The apparatus according to claim 156, wherein the locking
member is configured to be coupled to the first longitudinal member
at least 1 cm away from the first implantable member.
159. Apparatus for use at a native valve of a heart of a subject,
the apparatus comprising: a tissue anchor, configured to be
transluminally, transcatheterally advanced to a ventricle of the
heart of the subject, and to be coupled to tissue of the ventricle;
a longitudinal member, coupled at a distal end thereof to the
tissue anchor; a wire, a portion of the wire being reversibly
couplable to the longitudinal member; a tubular member: slidable
over the longitudinal member and the wire, shaped to define a lumen
therethrough, and configured, when the portion of the wire is (1)
coupled to the longitudinal member, and (2) disposed within the
lumen of the tubular member, to inhibit decoupling of the portion
of the wire from the longitudinal member; a prosthetic valve
support comprising an upstream support portion slidable over the
tubular member, and to be placed against an upstream surface of an
annulus of the native valve by sliding over the tubular member; and
a locking member, slidable over the tubular element and lockable to
the longitudinal member.
160. The apparatus according to claim 159, wherein the locking
member is configured to be locked to the longitudinal member at a
site of the longitudinal member that is distal to a site of the
longitudinal member to which the portion of the wire is reversibly
couplable.
161. The apparatus according to claim 159, wherein the tubular
member is configured to be slid out of the locking member before
the locking member is locked to the longitudinal member.
162. The apparatus according to any one of claims 159-161, further
comprising a control rod, slidable over the tubular member, the
locking member being reversibly coupled to a control rod, the
control rod being configured to restrain the locking member in an
unlocked configuration thereof, and to facilitate locking of the
locking member by ceasing to restrain the locking member in the
unlocked configuration.
163. The apparatus according to claim 162, wherein the control rod
is configured to decouple from the locking member when the control
rod ceases to restrain the locking member in the unlocked
configuration thereof.
164. The apparatus according to claim 162, wherein the control rod
is configured to cease to restrain the locking member in the
unlocked configuration thereof by the control rod being rotated
with respect to the locking member.
165. The apparatus according to claim 162, wherein: the prosthetic
valve support is shaped to define a hole through which the tubular
member is slidable, at least while the control rod is coupled to
the locking member, the control rod is not slidable through the
hole defined by the prosthetic valve support, and the control rod
is configured to facilitate the sliding of the prosthetic valve
support over the tubular member by pushing the prosthetic valve
support over the tubular member.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] The present application claims priority from U.S.
provisional patent application 61/756,049 to HaCohen et al., filed
Jan. 24, 2013, and entitled "Ventricularly-anchored prosthetic
valve support"; and U.S. provisional patent application 61/756,034
to HaCohen et al., filed Jan. 24, 2013, and entitled
"Tissue-engaging elements", and is related to:
[0002] US patent application publication 2012/0022639 to Hacohen et
al., filed Jul. 21, 2010;
[0003] US patent application publication 2012/0022640 to Gross et
al., filed Feb. 24, 2011;
[0004] U.S. patent application Ser. No. 13/811,308 to Gross et al.,
filed Jan. 21, 2013, which published as US 2013/0172992;
[0005] U.S. patent application Ser. No. 13/412,814 to Gross et al.,
filed Mar. 6, 2012, which published as US 2013/0035759;
[0006] PCT patent application IL2012/000292 to Gross et al., filed
Aug. 5, 2012, which published as WO/2013/021374;
[0007] PCT patent application IL2012/000293 to Gross et al., filed
Aug. 5, 2012, which published as WO/2013/021375; and a US patent
application to HaCohen et al., entitled "Anchoring of prosthetic
valve supports", filed on even date herewith, all of which are
incorporated herein by reference.
FIELD OF THE INVENTION
[0008] Some applications of the present invention relate in general
to valve replacement. More specifically, some applications of the
present invention relate to prosthetic cardiac valves and
techniques for implantation thereof.
BACKGROUND
[0009] Ischemic heart disease causes regurgitation of a heart valve
by the combination of ischemic dysfunction of the papillary
muscles, and the dilatation of the ventricle that is present in
ischemic heart disease, with the subsequent displacement of the
papillary muscles and the dilatation of the valve annulus.
[0010] Dilation of the annulus of the valve prevents the valve
leaflets from fully coapting when the valve is closed.
Regurgitation of blood from the ventricle into the atrium results
in increased total stroke volume and decreased cardiac output, and
ultimate weakening of the ventricle secondary to a volume overload
and a pressure overload of the atrium.
SUMMARY OF THE INVENTION
[0011] For some applications of the invention, tissue anchors
coupled to tethers are transluminally anchored to ventricular
tissue of a native valve. A prosthetic valve component, such as a
prosthetic valve assembly, a prosthetic valve body, or a support,
is transluminally slid along a guide member coupled to the tethers,
and is anchored to the tethers.
[0012] For some applications, a prosthetic valve assembly comprises
(1) a valve body shaped to define a lumen therethrough, and a valve
member disposed within the lumen, (2) an upstream support
configured to be placed against an upstream surface of a native
heart valve, and (2) a flexible sheet that couples the upstream
support to the valve body.
[0013] For some applications, the prosthetic valve assembly
comprises eyelets to facilitate sliding along the guide member.
[0014] For some applications, the prosthetic valve assembly has a
compressed delivery state in which the valve body and the upstream
support are articulatably coupled to each other by the sheet. For
such applications, a delivery tool houses the prosthetic valve
assembly such that the valve body and upstream support are
articulatable with respect to each other during transluminal
delivery.
[0015] For some applications, the prosthetic valve assembly
comprises tethers that, when tensioned, move the valve body closer
to the support. For such applications, the assembly typically
comprises tissue-engaging elements that protrude from the valve
body, and the tethers are tensioned to sandwich tissue of the
native valve between the tissue-engaging elements and the
support.
[0016] For some applications, one or more forces is measured during
implantation, and distributed among various anchoring elements. For
some such applications, an intracorporeal spring is used that is
extracorporeally observable using imaging techniques. For some such
applications, the spring facilitates force distribution.
[0017] For some applications, a prosthetic valve assembly comprises
a flexible sheet forms a pocket between the sheet and a frame of
the assembly, and facilitates sealing between the assembly and
tissue of the native valve.
[0018] For some applications of the invention, tissue anchors
coupled to longitudinal members that are reversibly couplable to
wires are transluminally advanced to the ventricle downstream of a
native heart valve, and are anchored there. A prosthetic valve
support comprising an upstream support portion is slid, in a
compressed delivery configuration, over the wires and part of each
longitudinal member, and into an atrium upstream of the native
valve where it is deployed (e.g., expanded) and placed against an
upstream surface (e.g., an atrial surface) of the native valve. A
locking member is also slid over the wires and part of each
longitudinal member, and locks to the longitudinal member, thereby
securing the prosthetic valve support against the upstream surface
of the native valve. A prosthetic valve is subsequently
transluminally advanced to the native valve, and is implanted by
coupling the prosthetic valve to leaflets of the native valve and
to the prosthetic valve support.
[0019] For some applications of the invention, a tubular member is
slidable over the wire and the longitudinal member, and when
disposed over the wire and the long member, inhibits decoupling of
the wire from the longitudinal member. For such applications, the
prosthetic valve support and the locking member are typically
slidable over the tubular member.
[0020] For some applications of the invention, a control rod,
reversibly coupled to the locking member, is slid over the tubular
member so as to push the locking member and the prosthetic valve
support over the tubular member. For some such applications, the
control rod is used to lock the locking member to the longitudinal
member.
[0021] There is therefore provided, in accordance with an
application of the present invention, apparatus for use with a
native valve of a heart of a subject, the apparatus including:
[0022] a valve body: [0023] including (1) a first frame shaped to
define a lumen therethrough, and (2) a valve member disposed within
the lumen, [0024] having a compressed state in which the first
frame has a first diameter, and [0025] having an expanded state in
which the first frame has a second diameter that is greater than
the first diameter;
[0026] an upstream support: [0027] configured to be placed against
an upstream surface of the native valve, [0028] including a second
frame, [0029] having a compressed state, and [0030] having an
expanded state in which the second frame is annular, has [0031] an
inner perimeter that defines an opening through the second frame,
and [0032] has an outer perimeter; and
[0033] a flexible sheet that couples the upstream support to the
valve body.
[0034] In an application, the upstream support is coupled to the
valve body only via the sheet.
[0035] In an application:
[0036] the valve body has an upstream end, a downstream end, and a
longitudinal axis therebetween along which the lumen is defined,
and
[0037] when the valve body is in the expanded state thereof and the
upstream support is in the expanded state thereof: [0038] the first
frame is attached to the second frame at the inner perimeter of the
second frame, and [0039] the sheet is attached to the valve body
and to the upstream support in a manner that defines a pocket
region between the sheet and at least the inner perimeter of the
second frame, the sheet not being attached to the first frame or
the second frame in the pocket region.
[0040] In an application, the sheet provides fluid communication
between the opening and the lumen.
[0041] In an application, the sheet is not attached to the inner
perimeter of the second frame.
[0042] In an application, the sheet is not attached to an upstream
end of the valve body.
[0043] In an application, the sheet is generally annular when the
valve body is in the expanded state thereof and the upstream
support is in the expanded state thereof.
[0044] In an application, the sheet is generally frustoconical when
the valve body is in the expanded state thereof and the upstream
support is in the expanded state thereof.
[0045] In an application, the sheet is attached to the inner
perimeter of the second frame.
[0046] In an application, the sheet is circumferentially attached
to the second frame at a radius that is greater than a radius of
the inner perimeter.
[0047] In an application, the sheet is circumferentially attached
to the second frame at the outer perimeter of the second frame.
[0048] In an application, the sheet is attached to an upstream end
of the valve body.
[0049] In an application, the first frame is generally cylindrical
in both the compressed state thereof and the expanded state
thereof.
[0050] In an application, the second frame is generally cylindrical
in the compressed state thereof.
[0051] In an application, the valve body includes at least one
downstream anchor, configured such that, in the expanded
configuration of the valve body, the anchor protrudes radially
outward from the first frame.
[0052] In an application, the apparatus further includes at least
one tensioning element, coupled to the valve body and to the
upstream support, a length of the tensioning element between the
valve body and the upstream portion being adjustable such that a
distance between the first frame and the second frame is
adjustable.
[0053] In an application, the at least one tensioning element
includes a tether.
[0054] In an application, the at least one tensioning element is
coupled to the first frame, and slidably coupled to the second
frame.
[0055] In an application, the valve body, the upstream support and
the sheet together define a prosthetic valve assembly, the
prosthetic valve assembly:
[0056] having an expanded state in which the valve body is in the
expanded state thereof and the second frame of the upstream support
is in the expanded state thereof,
[0057] having a compressed state in which: [0058] the prosthetic
valve assembly has a longitudinal axis, [0059] the valve body is in
the compressed state thereof at a first zone of the longitudinal
axis, [0060] the upstream support is in the compressed state
thereof at a second zone of the longitudinal axis, and [0061] the
prosthetic valve assembly defines an articulation zone, between the
first zone and the second zone, in which at least part of the sheet
is disposed, in which neither the first frame nor the second frame
is disposed, and about which the valve body and the upstream
support are articulatable with respect to each other.
[0062] In an application, the apparatus further includes a delivery
tool:
[0063] including a first housing configured to house and maintain
at least part of the upstream support in the compressed state
thereof, and defining a first housing orifice through which the at
least part of the upstream support is removable from the first
housing,
[0064] including a second housing configured to house and maintain
at least part of the valve body in the compressed state thereof,
and defining a second housing orifice through which the at least
part of the valve body is removable from the second housing,
[0065] having a contracted state in which the second housing is
disposed at a first distance from the first housing, and in which
the delivery tool is configured to transluminally advance the
prosthetic valve assembly in the compressed state thereof, to the
native valve, and
[0066] having an extended state in which the second housing is
disposed at a second distance from the first housing, the second
distance being greater than the first distance, and the apparatus
is configured such that, when the at least part of the upstream
support is housed by the first housing and the at least part of the
valve body is housed by the second housing, transitioning of the
delivery tool from the contracted state into the extended state
exposes at least part of at least one component selected from the
group consisting of: the valve body and the upstream support, from
the housing that houses the selected component.
[0067] In an application:
[0068] the apparatus is configured to be used with at least two
guide members,
[0069] the prosthetic valve assembly includes at least two eyelets,
each eyelet being slidable over a respective one of the guide
members, and
[0070] the apparatus is configured such that the eyelets of the
prosthetic valve assembly protrude radially outward and radially
beyond an outer surface of the second housing while: (1) the at
least part of the valve body, in the compressed state thereof, is
housed by the second housing, and (2) the at least part of the
upstream support, in the compressed state thereof, is housed by the
first housing.
[0071] In an application, the eyelets are pivotably coupled to the
valve body.
[0072] In an application, the delivery tool further includes at
least two reference-force tubes, each reference-force tube
configured (1) to be slidable over a respective one of the guide
members, and (2) to apply a distally-directed force to the
prosthetic valve assembly.
[0073] In an application, in the compressed state of the prosthetic
valve assembly, each reference-force tube extends distally (1)
through a lumen defined by the second frame of the upstream
support, (2) through the sheet, and (3) along an outside of at
least part of the valve body.
[0074] In an application, the apparatus further includes at least
two locking members, each locking member:
[0075] having an unlocked state in which the locking member is
slidable along a respective one of the guide members,
[0076] being transitionable into a locked state in which (1) the
locking member is locked to the respective one of the guide
members, and (2) the sliding of the eyelet over the guide member is
inhibited.
[0077] In an application, the apparatus further includes the at
least two guide members:
[0078] each guide member includes: [0079] a tubular member, shaped
to define a lumen therethrough, [0080] a tether, coupled at a
distal end thereof to a tissue anchor configured to be anchored to
ventricular tissue of the heart, at least a proximal portion of the
tether being disposed within the lumen of the tubular member, and
[0081] a pull-wire, coupled at a distal portion thereof to the
proximal portion of the tether, at least the distal portion of the
pull-wire being disposed within the lumen of the tubular
member,
[0082] the tubular member inhibits decoupling of the pull-wire from
the tether while the distal portion of the pull-wire and the
proximal portion of the tether are disposed within the lumen of the
tubular member, and
[0083] while the tubular member of each guide member is disposed
within the respective locking member, the tubular member inhibits
transitioning of the locking member into the locked state.
[0084] In an application, the apparatus is configured such that,
for each respective guide member and locking member, while (1) the
tubular member is disposed within the locking member, (2) the
distal portion of the pull-wire and the proximal portion of the
tether are disposed within the lumen of the tubular member, and (3)
the tissue anchor is coupled to the ventricular tissue:
[0085] proximal sliding of the tubular member with respect to the
tether facilitates automatic transitioning of the locking member
into the locked state, and
[0086] further proximal sliding of the tubular member with respect
to the tether facilitates decoupling of the pull-wire from the
tether.
[0087] In an application, at least one housing selected from the
group consisting of: the first housing and the second housing has a
lateral wall that is shaped to define at least two slits, the
eyelets being configured to protrude radially outward from the
delivery tool via the slits.
[0088] In an application, each slit of the at least one selected
housing is continuous with the orifice of the at least one selected
housing.
[0089] In an application, the eyelets are coupled to and protrude
radially outward from the valve body.
[0090] In an application, the eyelets are pivotably coupled to the
valve body.
[0091] In an application:
[0092] the articulation zone defined by the prosthetic valve
assembly includes a first articulation zone, and
[0093] while (1) the at least part of the valve body, in the
compressed state thereof, is housed by the second housing, (2) the
at least part of the upstream support, in the compressed state
thereof, is housed by the first housing, and (3) the delivery tool
is in the contracted state thereof, the apparatus defines a second
articulation zone at a longitudinal zone of the apparatus (a)
between the second housing and the first housing, and (b) in which
is disposed at least part of the first articulation zone.
[0094] In an application, the delivery tool further includes a
housing-control rod that extends through the first housing and is
coupled to the second housing such that a first portion of the
housing-control rod is disposed within the first housing, a second
portion of the housing-control rod is disposed within the second
housing, and a third portion of the housing-control rod (1) is
disposed within the second articulation zone, and (2) is more
flexible than at least one portion of the housing-control rod
selected from the group consisting of: the first portion and the
second portion.
[0095] In an application:
[0096] the delivery tool further includes (1) a control rod
assembly including at least a first housing-control rod coupled to
the first housing, and (2) a second housing-control rod, more
flexible than the first housing-control rod, extending through the
first housing-control rod, extending through the second
articulation zone, and coupled to the second housing.
[0097] In an application, the second housing orifice faces the
first housing orifice.
[0098] In an application:
[0099] the delivery tool further includes a flexible control rod
assembly including (1) a first housing-control rod coupled to the
first housing, (2) a second housing-control rod coupled to the
second housing, and (3) a prosthesis-control rod reversibly
couplable to the prosthetic valve assembly,
[0100] longitudinal movement of the second housing-control rod with
respect to the first housing-control rod transitions the delivery
tool between the contracted state and the extended state thereof,
and
[0101] the valve body is removable from the second housing by
moving the second housing-control rod with respect to the
prosthesis-control rod.
[0102] In an application, the prosthesis-control rod is reversibly
couplable to the prosthetic valve assembly by being reversibly
couplable to the valve body.
[0103] In an application, at least part of the second
housing-control rod is disposed within and slidable through the
prosthesis-control rod, and at least part of the prosthesis-control
rod is disposed within and slidable through the first
housing-control rod.
[0104] In an application, the outer perimeter of the second frame
has a third diameter that is greater than the second diameter.
[0105] In an application, the inner perimeter has a fourth diameter
that is greater than the second diameter.
[0106] In an application, when the valve body is in the expanded
state thereof and the upstream support is in the expanded state
thereof, a gap is defined between the first frame and the second
frame, the sheet spanning the gap.
[0107] In an application, no metallic structure is disposed within
the gap.
[0108] In an application, the sheet is configured to inhibit
expansion of the second frame.
[0109] In an application, the apparatus is configured such that
when the second frame expands from the compressed state thereof
toward the expanded state thereof, the sheet retains the second
frame in a generally frustoconical shape by inhibiting expansion of
at least the outer perimeter of the second frame.
[0110] In an application, the sheet extends over at least part of
the second frame to serve as a covering of the upstream
support.
[0111] In an application, the covering defines a tissue-contacting
surface of the upstream support.
[0112] In an application, the sheet extends over at least part of
the first frame to serve as a covering of the valve body.
[0113] In an application, the covering is disposed on an inner
surface of the first frame.
[0114] There is further provided, in accordance with an application
of the present invention, apparatus for use with a native valve of
a heart of a subject, the apparatus including:
[0115] a prosthetic valve, configured to be percutaneously
delivered to the native valve;
[0116] an annular upstream support, configured to be placed against
an upstream surface of the native valve, and to support the
prosthetic valve at the native valve;
[0117] a tissue anchor, including a tissue-engaging element
configured to be anchored to ventricular muscle tissue of the
heart;
[0118] a tether, coupled to the tissue anchor; and
[0119] a spring, couplable to the tether so as to elastically
couple the tissue-engaging element to the prosthetic valve.
[0120] In an application, the spring is shaped to define a
repeating pattern.
[0121] In an application, the spring is pre-loaded.
[0122] In an application, the spring is a constant-force
spring.
[0123] In an application, the spring is configured to facilitate
extracorporeal fluoroscopic observation of a state of the
spring.
[0124] In an application, the spring is coupled to a plurality of
radiopaque markers such that a juxtaposition of the markers changes
as the state of the spring changes, the juxtaposition of the
markers being extracorporeally fluoroscopically observable.
[0125] In an application, the spring is coupled to at least one
radiopaque marker, and the apparatus further includes an
intracorporeal reference, a juxtaposition between the radiopaque
marker and the intracorporeal reference being extracorporeally
fluoroscopically observable.
[0126] In an application, the intracorporeal reference includes a
scale including a plurality of radiopaque markers.
[0127] In an application, the plurality of radiopaque markers
includes a first plurality of radiopaque markers, and the at least
one radiopaque marker includes a second plurality of radiopaque
markers.
[0128] In an application, the spring is configured to provide
distinct indication that is observable using fluoroscopy, when the
spring is experiencing a force that is within a margin force from a
target force.
[0129] In an application, the spring is configured to provide the
distinct indication when the spring experiences a force that is
above 300 g force.
[0130] In an application, the spring is configured to provide the
distinct indication when the spring experiences a force that is
above 400 g force.
[0131] In an application, the spring is configured to provide the
distinct indication when the spring experiences a force that is
about 500 g force.
[0132] In an application, the spring is coupled to the prosthetic
valve, and is intracorporeally lockable to the tether subsequently
to anchoring of the tissue anchor to the ventricular muscle
tissue.
[0133] In an application, the spring is slidable along at least
part of the tether, and is intracorporeally couplable to the tether
by inhibiting the sliding.
[0134] In an application, the prosthetic valve includes a generally
cylindrical valve body having an upstream end, and the spring
includes an elastically-deformable appendage that protrudes
laterally from the valve body.
[0135] In an application:
[0136] the prosthetic valve includes a generally cylindrical valve
body having an upstream end, a downstream end, and a longitudinal
lumen therebetween, and
[0137] the spring (1) includes a compression spring having a
longitudinal axis, and (2) is disposed laterally from, the valve
body such that the longitudinal axis of the spring is generally
parallel with the longitudinal lumen.
[0138] In an application, the prosthetic valve includes:
[0139] a generally cylindrical valve body having an upstream end, a
downstream end, and a longitudinal lumen therebetween; and
[0140] one or more tissue-engaging legs, protruding laterally
outward from the valve body, and configured to be placed against a
ventricular surface of the native valve.
[0141] In an application, the prosthetic valve is couplable to the
upstream support intracorporeally by being expanded within an
opening defined by the upstream support while the upstream support
is disposed against the upstream surface.
[0142] In an application, the apparatus is configured such that the
coupling of the prosthetic valve to the upstream support couples
the tether to the prosthetic valve.
[0143] In an application, the apparatus is configured to sandwich a
portion of the native valve between the tissue-engaging legs and
the upstream support by providing a space having a height between
the tissue-engaging legs and the upstream support.
[0144] In an application, the apparatus is configured to facilitate
altering the height without altering a force on the spring.
[0145] In an application, the apparatus is configured such that
altering the height automatically alters a force on the spring.
[0146] In an application, the apparatus is configured to facilitate
altering the height by moving the valve body through the opening
defined by the upstream support.
[0147] There is further provided, in accordance with an application
of the present invention, apparatus for use with a native heart
valve of a subject, the apparatus including:
[0148] a valve body: [0149] having an upstream end, a downstream
end, and a longitudinal axis therebetween, [0150] including a
lateral wall that circumscribes the longitudinal axis and defines a
longitudinal lumen, and [0151] including a valve member disposed
within the lumen;
[0152] an upstream support having an inner perimeter couplable to
the valve body at a first longitudinal position of the valve body,
the upstream support being configured to extend radially outward
from the valve body and the inner perimeter; and
[0153] a flexible sheet defining a first aperture, a second
aperture and a lateral wall therebetween, a first portion of the
sheet that defines the first aperture being circumferentially
attached to the upstream support portion at a radius that is
greater than a radius of the inner perimeter, and a second portion
of the sheet that defines the second aperture being
circumferentially attached to the valve body at a second
longitudinal position of the valve body, such that a pocket region
is defined between the sheet and at least the first longitudinal
position.
[0154] In an application, the second longitudinal position is
closer to the downstream end of the valve body than is the first
longitudinal position.
[0155] In an application, the first aperture is larger than the
second aperture.
[0156] In an application, the sheet is attached to the upstream
support at an outer perimeter of the upstream support.
[0157] In an application, the sheet assumes a frustoconical
shape.
[0158] In an application, the sheet assumes a funnel shape.
[0159] In an application, the apparatus is provided with the inner
perimeter of the upstream support pre-coupled to the valve body at
the first longitudinal position of the valve body.
[0160] In an application, the apparatus is configured such that the
inner perimeter of the upstream support is intracorporeally
couplable to the valve body at the first longitudinal position of
the valve body.
[0161] There is further provided, in accordance with an application
of the present invention, apparatus for use with a native heart
valve disposed between an atrium and a ventricle of a heart of a
subject, the apparatus including:
[0162] an annular upstream support defining an opening
therethrough, and configured to be placed against an upstream
surface of the native heart valve;
[0163] a tubular valve body having an upstream end, a downstream
end and a lumen therebetween, the lumen having a first diameter,
and the valve body being separated from the upstream element by a
gap between the upstream end of the valve body and the upstream
element;
[0164] one or more tissue-engaging elements that protrude radially
outward from the valve body so as to define a second diameter that
is greater than the first diameter; and
[0165] a flexible sheet shaped to define a conduit, a downstream
portion of the sheet being coupled to the valve body, an upstream
portion of the sheet being coupled to the upstream element, and the
sheet spanning the gap.
[0166] In an application, the apparatus further includes at least
one tether, a first portion of the tether being coupled to the
valve body and a second portion of the tether being coupled to the
upstream support, such that tensioning of at least a portion of the
tether reduces the gap.
[0167] In an application, the apparatus is configured such that
tensioning of at least the portion of the tether rumples the
sheet.
[0168] There is further provided, in accordance with an application
of the present invention, apparatus for use with a native heart
valve disposed between an atrium and a ventricle of a heart of a
subject, the apparatus including:
[0169] an annular upstream element defining an opening
therethrough, and configured to be placed against an upstream
surface of the native heart valve;
[0170] a flexible sheet, shaped to define a conduit, and coupled to
the upstream element such that the conduit is in fluid
communication with the opening; and
[0171] a valve body, coupled to the flexible sheet such that the
conduit provides fluid communication between the prosthetic valve
and the upstream element.
[0172] In an application, the valve body includes:
[0173] a generally cylindrical frame shaped to define a lumen
therethrough, and
[0174] a valve member coupled to the frame and disposed within the
lumen.
[0175] In an application, the frame is separated from the upstream
element by a gap, and the conduit spans the gap.
[0176] There is further provided, in accordance with an application
of the present invention, apparatus, for use with a guide member
that extends into a subject, the apparatus including:
[0177] a delivery tool, including a housing, the housing: [0178]
being transluminally advanceable into the subject, [0179] shaped to
define an orifice at an end of the housing, and [0180] having a
lateral wall shaped to define a slit that is continuous with the
orifice;
[0181] an implant: [0182] configured to be housed by the housing,
and [0183] including an eyelet that (1) is slidable over the guide
member, and (2) when the implant is housed by the housing, extends
through the slit and radially beyond the lateral wall such that the
eyelet facilitates transluminal sliding of the implant and the
housing along the guide member and into the subject, the apparatus
being configured such that, while (1) the implant remains within
the subject, and (2) the guide member remains disposed through the
eyelet, (1) the implant is removable from the housing via the
orifice, and (2) the housing is removable from the subject.
[0184] In an application, the implant is configured to be implanted
by being intracorporeally locked to the guide member.
[0185] In an application, the implant has a compressed state and an
expanded state, is configured to be housed by the housing while in
the compressed state, and is configured to automatically expand
toward the expanded state when removed from the housing.
[0186] There is further provided, in accordance with an application
of the present invention, a method for use with a native valve of a
heart of a subject, the method including:
[0187] transluminally anchoring a tissue anchor to ventricular
tissue of a subject using an anchor-manipulation tool, the tissue
anchor being coupled to a first portion of a tether;
[0188] transluminally delivering an annular upstream support and a
prosthetic valve to the heart, the prosthetic valve including (1) a
valve body shaped to define a lumen therethrough, and (2) one or
more tissue-engaging legs configured to protrude laterally outward
from the valve body;
[0189] pressing the tissue-engaging legs in an upstream direction
against a ventricular surface of the native valve by applying a
force to the prosthetic valve while measuring the force;
[0190] applying, to the tether, a tension that changes a shape of a
spring coupled to the tether, while observing the shape of the
spring using imaging; and
[0191] at least in part responsively to the observed shape of the
spring, facilitating holding of the upstream support against an
upstream surface of the native valve by locking a second portion of
the tether to at least one component selected from the group
consisting of: the prosthetic valve and the upstream support.
[0192] In an application, measuring the force includes measuring
the force using an extracorporeal force meter.
[0193] In an application, measuring the force includes observing a
shape of the tissue-engaging legs using imaging.
[0194] In an application, applying the tension includes applying
the tension while applying the force.
[0195] In an application, locking the second portion to the
selected component includes locking the second portion to the
prosthetic valve.
[0196] In an application, locking the second portion to the
selected component includes locking the second portion to the
upstream support.
[0197] In an application, locking the second portion includes
locking the second portion when the observed shape indicates that
the spring is experiencing between 400 g force and 600 g force.
[0198] In an application, locking the second portion includes
locking the second portion subsequently to applying the tension,
and applying the force includes applying the force subsequently to
locking the second portion.
[0199] In an application:
[0200] anchoring the tissue anchor coupled to the tether includes
anchoring a first tissue anchor coupled to a first tether, and
applying the tension includes applying a first tension that changes
a shape of a first spring coupled to the first tether,
[0201] the method further includes: [0202] anchoring a second
tissue anchor to the ventricular tissue, the second tissue anchor
being coupled to a first portion of a second tether; and [0203]
applying, to the second tether, a second tension that changes a
shape of a second spring coupled to the second tether, while
observing the shape of the second spring using imaging, and
[0204] facilitating holding of the prosthetic valve against the
upstream surface includes, at least in part responsively to the
observed shape of the second spring, facilitating holding of the
prosthetic valve against the upstream surface by locking a second
portion of the second tether to the selected at least one
component.
[0205] In an application, facilitating holding includes locking the
second portion of the first tether and the second portion of the
second tether to the selected at least one component, at least in
part responsively to a ratio between tension in the first tether
and tension in the second tether, the ratio being derived from the
observed shape of the first spring and the observed shape of the
second spring.
[0206] In an application, locking includes locking the second
portion to the at least one component at least in part responsively
to the observed shape.
[0207] In an application, locking includes locking the second
portion to the at least one component at least in part responsively
to the measured force.
[0208] In an application, applying the force includes moving the
valve body in an upstream direction through an opening defined by
the upstream support, and the method further includes coupling the
prosthetic valve to the upstream support by expanding the valve
body within the opening.
[0209] In an application, coupling the prosthetic valve to the
upstream support includes coupling the prosthetic valve to the
upstream support at least in part responsively to the measured
force.
[0210] There is further provided, in accordance with an application
of the present invention, a method, including:
[0211] transluminally advancing a plurality of tissue anchors,
coupled to a respective plurality of springs, into a body of a
subject;
[0212] anchoring the plurality of tissue anchors to tissue of the
subject;
[0213] tensioning at least one of the springs;
[0214] using imaging, while the tension is applied to the at least
one spring, observing a state of the at least one spring; and
[0215] at least in part responsively to the observed state of at
least one spring, adjusting a tension on at least one of the
springs.
[0216] There is further provided, in accordance with an application
of the present invention, a method, for use with a native valve of
a heart of a subject, the method including:
[0217] applying a first tension to a tether that couples (a) a
tissue anchor anchored to ventricular tissue of a subject, to (b) a
prosthetic valve body, the tether having a length between the
tissue anchor and the valve body;
[0218] by applying an atrially-directed force to the prosthetic
valve body, pressing, against tissue of the native valve, a
tissue-engaging element that protrudes radially from the valve
body
[0219] transluminally advancing a prosthetic valve body to a native
valve of the subject;
[0220] while applying the atrially-directed force, measuring:
[0221] a pressing force of the tissue-engaging element against the
tissue of the native valve, and [0222] a second tension on the
tether, the second tension differing from the first tension at
least in part due to the atrially-directed force; and
[0223] at least in part responsively to the measured pressing force
and the measured second tension, performing an action selected from
the group consisting of: adjusting the length of the tether between
the tissue anchor and the valve body, and locking the valve body to
the tether.
[0224] There is further provided, in accordance with an application
of the present invention, a method for use with a native valve of a
heart of a subject, the method including:
[0225] transluminally delivering a tissue anchor to a ventricle of
the heart, and anchoring the tissue anchor to ventricular muscle
tissue of the subject;
[0226] transluminally delivering an upstream support to an atrium
of the heart, and placing the upstream support against an upstream
surface of an annulus of the native valve; and
[0227] changing a shape of the upstream support by tensioning a
tether coupled to upstream support and to the tissue anchor;
and
[0228] extracorporeally fluoroscopically observing the shape change
of the upstream support.
[0229] In an application, tensioning the tether coupled to the
upstream support includes tensioning a tether that is coupled to a
valve body coupled to the upstream support.
[0230] In an application, before the tensioning, the upstream
support is generally flat annular, and changing the shape includes
making the support assume a frustoconical shape.
[0231] In an application, before the tensioning, the upstream
support is frustoconical, and changing the shape includes changing
a slant of the frustoconical shape.
[0232] There is further provided, in accordance with an application
of the present invention, apparatus for use with a valve of a heart
of a subject, the apparatus including:
[0233] a transluminally-deliverable tissue anchor;
[0234] a tether, a first end thereof coupled to the tissue anchor;
and
[0235] a delivery tool, including: [0236] a steerable catheter
having a longitudinal axis, and being transluminally deliverable to
the valve, and [0237] an obstructing element: [0238] disposed at a
longitudinal site of the catheter, [0239] configured to extend
laterally outward from the catheter, and [0240] dimensioned, when
extending laterally outward from the catheter, to inhibit movement
of at least the longitudinal site through the valve by abutting
tissue of the valve, and [0241] an anchor manipulator: [0242]
reversibly couplable to the tissue anchor, [0243] slidable through
the catheter, and [0244] configured to drive the anchor into
ventricular tissue of the heart of the subject.
[0245] In an application, the anchor manipulator is slidably
coupled to the catheter such that a distal end of the anchor
manipulator is slidable distally no more than a pre-determined
distance from the longitudinal site.
[0246] In an application, the apparatus further includes an
implant, intracorporeally lockable to the tether.
[0247] In an application, the apparatus further includes a guide
member, reversibly couplable to the tether, and the implant is
intracorporeally slidable along the guide member toward the tether
and the implant.
[0248] In an application, the tether has exactly one locking site
at which the implant is lockable to the tether.
[0249] In an application, the exactly one locking site is disposed
at a pre-determined distance from the anchor that is pre-determined
at least in part dependently on a distance between the longitudinal
site and a distal end of the catheter.
[0250] There is further provided, in accordance with an application
of the present invention, a method, including:
[0251] transluminally anchoring a tissue anchor to tissue of a
subject using an anchor-manipulation tool;
[0252] subsequently applying to the anchor a pulling force having a
given magnitude;
[0253] using imaging, observing a movement of the tissue anchor in
response to the pulling force; and
[0254] at least in part responsively to the observed movement,
performing an action selected from the group consisting of:
de-anchoring the tissue anchor from the tissue, and decoupling the
anchor-manipulation tool from the tissue anchor.
[0255] There is further provided, in accordance with an application
of the present invention, apparatus, for implantation at a native
valve of a heart of a subject, the native valve being disposed
between an atrium and a ventricle of the heart, the apparatus
including:
[0256] a tubular valve body: [0257] having an upstream portion,
configured to be disposed in the atrium of the heart of the
subject, [0258] having a downstream portion, configured to be
disposed in the ventricle of the subject, [0259] having an elastic
portion, disposed between the upstream portion and the downstream
portion, and elastically coupling the upstream portion to the
downstream portion, and [0260] shaped to define a continuous lumen
through the upstream portion, the elastic portion, and the
downstream portion; and
[0261] at least one valve member, disposed in the lumen of the
valve body, and configured to facilitate flow of blood of the
subject from the upstream portion of the valve body to the
downstream portion of the valve body, and to inhibit flow of the
blood from the downstream portion of the valve body to the upstream
portion of the valve body.
[0262] In an application, the at least one valve member is coupled
to the downstream portion of the valve body.
[0263] In an application, the native valve includes a plurality of
native leaflets, and the downstream portion of the valve body is
configured to be coupled to the native leaflets.
[0264] In an application, the apparatus further includes a
plurality of clips, configured to facilitate the coupling of the
downstream portion of the valve body to the native leaflets.
[0265] In an application, each clip:
[0266] includes at least two clip arms, articulatably coupled to
each other, and
[0267] is reversibly closeable.
[0268] In an application, the clips are coupled to the downstream
portion of the valve body, and the downstream portion of the valve
body is configured to be coupled to the native leaflets by the
clips being coupled to the native leaflets.
[0269] In an application, each clip of the plurality of clips is
articulatably coupled to the downstream portion of the valve
body.
[0270] In an application, the native valve includes an annulus
having an upstream surface, and the apparatus further includes a
prosthetic valve support:
[0271] including (1) an upstream support portion, configured to be
placed against the upstream surface of the annulus of the native
valve, and (2) the plurality of clips, coupled to the upstream
support portion,
[0272] shaped to define an opening therethrough that is configured
to receive the prosthetic valve,
[0273] and the clips are configured to facilitate the coupling of
the downstream portion of the valve body to the native leaflets by
coupling the prosthetic valve support to the native leaflets.
[0274] There is further provided, in accordance with an application
of the present invention, apparatus for use with a native valve of
a heart of a subject, the native valve having a plurality of
leaflets that meet at a plurality of commissures, the apparatus
including:
[0275] at least one tissue anchor, configured to be anchored to a
first site within a ventricle of the heart of the subject;
[0276] at least one longitudinal member, coupled at a distal end
thereof to a respective one of the at least one tissue anchors;
[0277] an upstream support, including an upstream support portion
configured to be slidable over the longitudinal member and placed
against an upstream surface of the native valve; and
[0278] at least one locking member, configured to be slidable over
a respective one of the at least one longitudinal members, and to
be lockable to the respective longitudinal member such that a
portion of the respective longitudinal member that is disposed
between the respective anchor and the upstream support portion is
longer than 1 cm.
[0279] In an application, the longitudinal member is flexible.
[0280] In an application, the longitudinal member includes a
suture.
[0281] There is further provided, in accordance with an application
of the present invention, a method for use with a native valve of a
heart of a subject, the native valve having a plurality of leaflets
that meet at a first commissure and at a second commissure, the
method including:
[0282] anchoring a first tissue anchor to a first site within a
ventricle of the heart of the subject, the first tissue anchor
being coupled to a distal end of a first longitudinal member;
[0283] anchoring a second tissue anchor to a second site within the
ventricle of the heart of the subject, the second tissue anchor
being coupled to a distal end of a second longitudinal member;
[0284] subsequently, placing at least an upstream support portion
of a prosthetic valve support against an upstream surface of the
native valve, the valve being disposed between the ventricle and an
atrium of the heart of the subject; and
[0285] securing the upstream support portion against the upstream
surface of the valve by: [0286] coupling the upstream support
portion to the first longitudinal member such that at least part of
a portion of the first longitudinal member that is disposed between
the upstream support portion and the first tissue anchor, is
disposed between the first and second leaflets at the first
commissure, and [0287] coupling the upstream support portion to the
second longitudinal member such that at least part of a portion of
the second longitudinal member that is disposed between the
upstream support portion and the first tissue anchor, is disposed
between the first and second leaflets at the second commissure.
[0288] In an application, anchoring, placing, and securing include
anchoring, securing, and placing without the use of cardiopulmonary
bypass.
[0289] In an application, anchoring to the first site and anchoring
to the second site include anchoring to myocardium.
[0290] In an application, placing the upstream support portion
against the upstream surface includes sliding the upstream support
portion over at least part of the first longitudinal member.
[0291] In an application, coupling the upstream support portion to
the first longitudinal member and to the second longitudinal member
includes coupling the upstream support portion to the first
longitudinal member in the atrium of the heart of the subject, and
coupling the upstream support portion to the second longitudinal
member includes coupling the upstream support portion to the second
longitudinal member in the atrium of the heart of the subject.
[0292] In an application, the leaflets move in response to beating
of the heart of the subject, and securing the upstream support
portion includes securing the upstream support portion without
eliminating the movement of the native leaflets.
[0293] In an application, coupling the upstream support portion to
the first longitudinal member includes coupling the upstream
support portion to the first longitudinal member such that a length
of the portion of the first longitudinal member is greater than 1
cm.
[0294] In an application, the method further includes:
[0295] transluminally advancing at least the first tissue anchor to
the first site while the respective longitudinal member coupled
thereto is disposed within a respective tubular member; and
[0296] subsequently to anchoring the at least first tissue anchor,
and before coupling the upstream support portion to the respective
longitudinal member, sliding the at least first tubular member off
of at least part of the respective longitudinal member.
[0297] In an application, sliding the at least first tubular member
includes sliding at least part of the at least first tubular member
through a channel defined by a locking member, and coupling the
upstream support portion to the respective longitudinal member
includes locking the locking member to the respective longitudinal
member by narrowing at least a portion of the channel.
[0298] In an application:
[0299] advancing the at least first tissue anchor includes
advancing the at least first tissue anchor while (1) the respective
longitudinal member is reversibly coupled to a portion of a wire,
and (2) the respective tubular member inhibits the portion of the
wire from decoupling from the portion of the wire, and
[0300] the method further includes facilitating decoupling of the
wire from the respective longitudinal member by sliding the at
least first tubular member off of the portion of the wire.
[0301] In an application:
[0302] advancing the at least first tissue anchor includes
advancing the at least first tissue anchor while (1) the respective
longitudinal member is shaped to define a loop, and is coupled to
the portion of the wire by the portion of the wire being threaded
through the loop, and (2) the respective tubular member inhibits
the portion of the wire from unthreading from the loop, and
[0303] facilitating decoupling of the wire from the respective
longitudinal member includes facilitating unthreading of the wire
from the loop by sliding the at least first tubular member off of
the portion of the wire.
[0304] In an application, sliding the at least first tubular member
off of the portion of the wire includes sliding the at least first
tubular member off of the portion of the wire by applying less than
500 g of pulling force to the at least first tubular member.
[0305] In an application, applying less than 500 g of pulling force
to the at least first tubular member includes applying less than
300 g of pulling force to the at least first tubular member.
[0306] In an application, the method further includes, subsequently
to securing the upstream support portion, coupling a prosthetic
valve to the prosthetic valve support.
[0307] In an application, the upstream support portion has an inner
edge that defines an opening through the upstream support portion,
and coupling the prosthetic valve to the prosthetic valve support
includes placing at least a portion of the prosthetic valve within
the opening, and expanding at least the portion of the prosthetic
valve such that at least the portion of the prosthetic valve
applies a radially-expansive force against the inner edge of the
upstream support portion.
[0308] In an application, the prosthetic valve includes one or more
tissue-engaging elements, each of the one or more tissue-engaging
elements including at least two arms, and the method further
includes, subsequent to securing the upstream support portion,
coupling the prosthetic valve to at least one of the leaflets by
sandwiching the at least one of the leaflets between the at least
clip arms of the one or more tissue-engaging elements.
[0309] In an application, coupling the prosthetic valve to the at
least one of the leaflets includes coupling the prosthetic valve to
the at least one of the leaflets before coupling the prosthetic
valve to the prosthetic valve support.
[0310] In an application:
[0311] the prosthetic valve includes a valve body, having an outer
surface,
[0312] the at least two arms include a first arm and a second arm,
the first arm being longer than the second arm, and
[0313] the method further includes: [0314] delivering, within a
delivery tube, the prosthetic valve in a delivery configuration
thereof, in which the first arm and the second arm are constrained
against the outer surface of the valve body; [0315] facilitating
deflection of the first arm away from the outer surface of the
prosthetic valve, by advancing a first portion of the prosthetic
valve out of the delivery tube such that the first arm
automatically deflects away from the outer surface of the
prosthetic valve; and [0316] facilitating deflection of the second
arm away from the outer surface of the prosthetic valve, by
advancing a second portion of the prosthetic valve out of the
delivery tube such that the second arm automatically deflects away
from the outer surface of the prosthetic valve.
[0317] In an application:
[0318] facilitating deflection of the first arm includes
facilitating deflection of the first arm a first angle from the
outer surface of the prosthetic valve, and
[0319] the method further includes facilitating deflection of the
first arm away from the outer surface of the prosthetic valve a
second angle that is greater than the first angle, by applying a
force to the first arm using the delivery tube: [0320] subsequently
to facilitating deflection of the first arm the first angle, and
[0321] prior to facilitating deflection of the second arm.
[0322] In an application, applying the force to the first arm using
the delivery tube includes pushing on the first arm by sliding the
delivery tube over at least part of the prosthetic valve.
[0323] There is further provided, in accordance with an application
of the present invention, apparatus for use with a body of a
subject, the apparatus including:
[0324] at least a first implantable member;
[0325] a first longitudinal member, coupled at a distal end thereof
to the first implantable member;
[0326] a second longitudinal member, at least a portion of the
second longitudinal member being reversibly couplable to the first
longitudinal member; and
[0327] a tubular member: [0328] slidable over the first and second
longitudinal members, [0329] shaped to define a lumen therethrough,
and [0330] configured, when the portion of the second longitudinal
member is (1) coupled to the first longitudinal member, and (2)
disposed within the lumen of the tubular member, to inhibit
decoupling of the portion of the second longitudinal member from
the first longitudinal member.
[0331] In an application, the portion of the second longitudinal
member is configured, when (1) the portion of the second
longitudinal member is coupled to the first longitudinal member,
and (2) the portion of the second longitudinal member is disposed
outside of the lumen of the tubular member, to be decouplable from
the first longitudinal member by the second longitudinal member
being pulled away from the first longitudinal member.
[0332] In an application, at least one longitudinal member selected
from the group consisting of: the first longitudinal member and the
second longitudinal member, is flexible.
[0333] In an application, the tubular member is more rigid than the
first longitudinal member.
[0334] In an application, the tubular member fits snugly over at
least the portion of the second longitudinal member.
[0335] In an application, the first implantable member includes a
tissue anchor, configured to be anchored to a tissue of the
subject.
[0336] In an application, the apparatus further includes a second
implantable member, slidable over the tubular member, and couplable
to the first longitudinal member while the portion of the second
longitudinal member is coupled to the first longitudinal
member.
[0337] In an application, the portion of the second longitudinal
member is reversibly couplable to the first longitudinal member at
a first site of the first longitudinal member, and the second
implantable member is couplable to the first longitudinal member at
a second site of the first longitudinal member that is distal to
the first site of the longitudinal member.
[0338] In an application, the apparatus further includes a locking
member having an unlocked state and a locked state, and configured
to be slid over the tubular member in the unlocked state and to be
locked to the first longitudinal member by being transitioned to
the locked state.
[0339] In an application, the locking member is configured to
facilitate coupling of the second implantable member to the first
longitudinal member.
[0340] In an application, the locking member is configured to be
coupled to the first longitudinal member at least 1 cm away from
the first implantable member.
[0341] There is further provided, in accordance with an application
of the present invention, apparatus for use at a native valve of a
heart of a subject, the apparatus including:
[0342] a tissue anchor, configured to be transluminally,
transcatheterally advanced to a ventricle of the heart of the
subject, and to be coupled to tissue of the ventricle;
[0343] a longitudinal member, coupled at a distal end thereof to
the tissue anchor;
[0344] a wire, a portion of the wire being reversibly couplable to
the longitudinal member;
[0345] a tubular member: [0346] slidable over the longitudinal
member and the wire, [0347] shaped to define a lumen therethrough,
and
[0348] configured, when the portion of the wire is (1) coupled to
the longitudinal member, and (2) disposed within the lumen of the
tubular member, to inhibit decoupling of the portion of the wire
from the longitudinal member;
[0349] a prosthetic valve support including an upstream support
portion slidable over the tubular member, and to be placed against
an upstream surface of an annulus of the native valve by sliding
over the tubular member; and
[0350] a locking member, slidable over the tubular element and
lockable to the longitudinal member.
[0351] In an application, the locking member is configured to be
locked to the longitudinal member at a site of the longitudinal
member that is distal to a site of the longitudinal member to which
the portion of the wire is reversibly couplable.
[0352] In an application, the tubular member is configured to be
slid out of the locking member before the locking member is locked
to the longitudinal member.
[0353] In an application, the apparatus further includes a control
rod, slidable over the tubular member, the locking member being
reversibly coupled to a control rod, the control rod being
configured to restrain the locking member in an unlocked
configuration thereof, and to facilitate locking of the locking
member by ceasing to restrain the locking member in the unlocked
configuration.
[0354] In an application, the control rod is configured to decouple
from the locking member when the control rod ceases to restrain the
locking member in the unlocked configuration thereof.
[0355] In an application, the control rod is configured to cease to
restrain the locking member in the unlocked configuration thereof
by the control rod being rotated with respect to the locking
member.
[0356] In an application:
[0357] the prosthetic valve support is shaped to define a hole
through which the tubular member is slidable,
[0358] at least while the control rod is coupled to the locking
member, the control rod is not slidable through the hole defined by
the prosthetic valve support, and
the control rod is configured to facilitate the sliding of the
prosthetic valve support over the tubular member by pushing the
prosthetic valve support over the tubular member.
[0359] The present invention will be more fully understood from the
following detailed description of applications thereof, taken
together with the drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0360] FIGS. 1A-F are schematic illustrations of a system for
implanting a prosthetic valve support and a prosthetic valve at a
native valve of a heart of a subject, in accordance with some
applications of the invention;
[0361] FIG. 2 is a schematic illustration of the prosthetic valve
being retrieved into a delivery tube, in accordance with some
applications of the invention;
[0362] FIGS. 3A-C are schematic illustrations of the introduction
of guide members through the prosthetic valve support and a
delivery tube, in accordance with some applications of the
invention;
[0363] FIGS. 4A-C are schematic illustrations of a locking member,
and control thereof, in accordance with some applications of the
invention;
[0364] FIG. 5 is a schematic illustration of steps in the delivery
and anchoring of tissue anchors, in accordance with some
applications of the invention;
[0365] FIG. 6 is a schematic illustration of a system for use with
a prosthetic valve support, in accordance with some applications of
the invention;
[0366] FIGS. 7A-C are schematic illustrations of a system for
facilitating transluminal delivery of a prosthetic valve assembly,
in accordance with some applications of the invention;
[0367] FIGS. 8A-H are schematic illustrations of a technique for
use with the system of FIGS. 7A-C, to transluminally implant a
prosthetic valve assembly, in accordance with some applications of
the invention;
[0368] FIGS. 9A-B, 10A-B, 11A-B, 12A-B, 13A-B, and 14A-B are
schematic illustrations of prosthetic valve assemblies, in
accordance with some applications of the invention;
[0369] FIGS. 15A-C are schematic illustrations of a tool for
facilitating application of force between a prosthetic valve
assembly and tethers, in accordance with some applications of the
invention;
[0370] FIG. 16 is a schematic illustration of a system comprising a
prosthetic valve assembly and one or more springs, via which the
prosthetic valve assembly is elastically coupled to one or more
tissue anchors, in accordance with some applications of the
invention;
[0371] FIG. 17 is a schematic illustration of a system comprising a
prosthetic valve assembly and one or more springs, via which the
prosthetic valve assembly is elastically coupled to one or more
tissue anchors, in accordance with some applications of the
invention;
[0372] FIGS. 18A-B are schematic illustrations of springs coupled
to respective tethers so as to elastically couple a tissue anchor
to a prosthetic valve assembly, in accordance with some
applications of the invention;
[0373] FIGS. 19A-B are schematic illustrations of a system for
facilitating delivery of a prosthetic valve body, in accordance
with some applications of the invention;
[0374] FIG. 20 is a schematic illustration showing examples in
which force measurements described herein may be combined to
facilitate implantation of a prosthetic valve, in accordance with
some applications of the invention;
[0375] FIGS. 21A-B are schematic illustrations of a prosthetic
valve assembly, in accordance with some applications of the
invention;
[0376] FIGS. 22A-B are schematic illustrations of a prosthetic
valve assembly comprising a prosthetic valve having a tubular valve
body that comprises an upstream portion, a downstream portion, and
an elastic portion disposed between the upstream portion and the
downstream portion, in accordance with some applications of the
invention; and
[0377] FIGS. 23-24 are schematic illustrations of systems for
facilitating anchoring of a tissue anchor in the heart of a
subject, in accordance with some applications of the invention.
DETAILED DESCRIPTION OF EMBODIMENTS
[0378] Reference is made to FIGS. 1A-F, which are schematic
illustrations of a system 40 for implanting an upstream prosthetic
valve support 42 and a prosthetic valve 44 at a native valve 10 of
a heart 4 of a subject, in accordance with some applications of the
invention. Typically, applications of the invention are for use
with the mitral valve of the subject (that is, native valve 10
comprises the mitral valve of the subject), but it is to be noted
that applications of the invention may be used at other heart
valves of the subject, such as the tricuspid valve, the aortic
valve, or the pulmonary valve, mutatis mutandis.
[0379] Reference is now made to FIGS. 1A-B. A sheath 46 is advanced
transluminally (e.g., transfemorally) to right atrium 12 of the
heart, and is typically advanced through the fossa ovalis into left
atrium 6 of the heart using standard transseptal techniques. For
some applications, sheath 46 is steerable. For some such
applications, sheath 46 is steerable in two axes. One or more
(typically two) tissue anchors 48 are advanced through sheath 46,
between leaflets 14 of the native valve, and into left ventricle 8
of the heart, and are there anchored to tissue (e.g., ventricular
muscle tissue) of the heart. FIG. 1A shows a first tissue anchor
48a being anchored at a first ventricular site, and FIG. 1B shows a
second tissue anchor 48b being anchored at a second ventricular
site. Typically, anchors 48 are anchored to muscle of the heart,
such as to the walls of ventricle 8 and/or to papillary muscles.
Typically, and as shown, anchors 48 comprise helical anchors that
are anchored by being rotated. However, other types of anchors may
be used, such as barbed or harpoon-like anchors, e.g., that are
anchored by being pushed into the tissue.
[0380] State A of FIGS. 1A and 1B show a catheter 50 having been
advanced through sheath 46 and into ventricle 8, and an
anchor-delivery tube 52 having been advanced through catheter 50 to
the respective ventricular site. Typically, and as shown, the
distal end of delivery tube 52 is placed against the tissue at the
ventricular site. Typically, at least a distal portion of catheter
50 is steerable (e.g., independently of sheath 46).
[0381] State B of FIGS. 1A and 1B each show a respective anchor 48
being anchored to a respective ventricular site. Typically, anchor
48 is reversibly coupled to an anchor manipulator 54 (e.g., an
anchor driver), which is slidable through at least part of tube 52,
and which is configured to apply a force (e.g., a rotational force)
to the anchor so as to anchor the anchor at the ventricular site.
For some applications, anchor manipulator 54 and anchor 48 are
advanced from outside the subject to the ventricular site only once
the distal end of tube 52 is disposed against the ventricular site.
For some applications, the manipulator and anchor are disposed
within, and advanced with, tube 52. For some applications, anchor
48 is anchored by rotating anchor manipulator 54 and tube 52
together. For some applications, a separate anchor manipulator 54
is used to deliver and anchor each anchor 48 (e.g., each anchor 48
may be provided pre-coupled to a respective anchor manipulator).
For some applications, one anchor manipulator 54 may be used to
deliver and anchor all (e.g., both) anchors 48 (e.g., each anchor
48 may be configured to be sequentially coupled to the anchor
manipulator outside the body of the subject by the operating
physician). It is to be noted that typically anchor 48 is not
exposed from tube 52 other than when being anchored. It is
hypothesized that for some applications this reduces a likelihood
of inadvertently engaging and/or damaging tissue of the heart
(e.g., chordae tendineae).
[0382] For some applications, subsequent to anchoring each tissue
anchor 48 to the tissue, a testing pulling force of known magnitude
is applied to the anchor (e.g., by applying the pulling force to
anchor manipulator 54), and movement of the tissue anchor in
response to the pulling force is observed using imaging (e.g.,
fluoroscopy). The observed movement may be used to confirm
successful and/or stable anchoring (e.g., relatively little
movement may indicate firm anchoring in firm tissue) or to
determine sub-optimal anchoring (e.g., relatively large movement
may indicate weak anchoring and/or anchoring in weak tissue). Thus,
at least in part responsively to the observed movement, the
operating physician may decouple manipulator 54 from anchor 48, or
may de-anchor the anchor from the tissue using the manipulator.
[0383] State C of FIGS. 1A and 1B show anchor manipulator 54 having
been decoupled from anchor 48, and the manipulator and tube 52
being withdrawn proximally into catheter 50. Each anchor 48 is
provided pre-coupled to a guide member 56 (e.g., a first guide
member 56a, and a second guide member 56b), described in more
detail hereinbelow (e.g., with reference to FIGS. 1D and 4A-C). As
manipulator 54 and tube 52 are withdrawn, guide member 56 is
exposed from tube 52.
[0384] Typically, and as shown in FIGS. 1A-B, the same catheter 50
is used to deliver both anchors 48. For such applications, and as
shown in states B and C of FIG. 1B, when delivering second tissue
anchor 48b, anchor-delivery tube 52 fits alongside first guide
member 56a within catheter 50. Alternatively, and as described
hereinbelow with reference to FIG. 5, a separate catheter is used
for each anchor, in which case the second catheter fits alongside
first guide member 56a within sheath 46.
[0385] State D of FIGS. 1A and 1B show catheter 50 having been
withdrawn proximally, into atrium 6. For some applications,
catheter 50 is withdrawn completely from the body of the subject.
For some applications, catheter 50 is used for delivery of
components during later steps in the procedure. Guide members 56
extend from atrium 6, between leaflets 14, and to respective
ventricular sites. Typically, guide members 56 do not eliminate
functioning of leaflets 14 and/or valve 10. For some applications,
guide members 56 are configured to automatically move toward
respective commissures 16 (e.g., into the joining corners at the
commissures of leaflets 14). For some applications, and as shown in
FIG. 1C, prosthetic valve support 42 (e.g., deployment thereof)
pushes guide members 56 toward the respective commissures.
[0386] Reference is now made to FIG. 1C, which shows prosthetic
valve support being delivered to, and deployed at, native valve 10.
Prosthetic valve support 42 is advanced through sheath 46 and into
atrium 6. Typically, support 42 is delivered in a compressed
configuration thereof, within a housing, such as a delivery tube
80. For some applications, catheter 50 is used to facilitate
delivery of prosthetic valve support 42 and delivery tube 80 (e.g.,
the support and delivery tube are advanced through catheter 50).
For some applications, a different catheter is used to facilitate
delivery of prosthetic valve support 42 and delivery tube 80. For
some applications, prosthetic valve support 42 and delivery tube 80
are advanced directly through sheath 46.
[0387] Prosthetic valve support 42 comprises an annular upstream
support portion 43 which, in the delivery configuration of the
prosthetic valve support, is generally cylindrical, and which, once
the prosthetic valve is deployed and expands to an uncompressed
configuration thereof, is generally annular. For some applications,
upstream support portion 43 is generally frustoconical in the
uncompressed configuration thereof. Typically, a distal end of
upstream support portion 43 in the compressed, cylindrical
configuration, defines an inner perimeter of the upstream support
portion in the uncompressed configuration, the inner perimeter
defining an opening through the upstream support portion.
[0388] State A of FIG. 1C shows delivery tube 80, containing
support 42, having been delivered to atrium 6 over guide members
56, and support 42 starting to be subsequently exposed from the
delivery tube, and automatically expanding. Upstream support
portion 43 of prosthetic valve support 42 is shaped to define holes
82 through which guide members 56 are slidable, thereby
facilitating sliding of the prosthetic valve support over guide
members 56. Typically, holes 82 are disposed opposite each other
around the generally annular shape of upstream support portion 43.
For some applications, holes 82 are defined and/or reinforced by an
eyelet 84 or pledget (visible in states B and C of FIG. 1C). Guide
members 56 extend proximally from delivery tube 80, e.g., via holes
in a proximal end of the delivery tube, such that the delivery
tube, and prosthetic valve support 42, in the compressed state
within the delivery tube, are slidable over the guide members, the
guide members thereby facilitating delivery of the prosthetic valve
support within the delivery tube. Introduction of guide members 56
through the prosthetic valve support and delivery tube are
described hereinbelow with reference to FIGS. 3A-C.
[0389] State B of FIG. 1C shows prosthetic valve support 42 (e.g.,
upstream support portion 43 thereof) having been completely
deployed from delivery tube 80, and having automatically expanded
to the uncompressed configuration thereof. Guide members 56 are
typically pushed toward commissures 16 by the expansion of support
42. For some applications, delivery tube 80 is subsequently removed
from the body of the subject. A tubular control rod 86 is advanced
over each guide member 56 toward prosthetic valve support 42, and
is used to push prosthetic valve support 42 (e.g., upstream support
portion 43 thereof) toward the annulus of valve 10. Control rods 86
have a cross-sectional diameter that is larger than that of holes
82, and may thereby be used to push against upstream support
portion 43 without passing through the holes.
[0390] Typically, prosthetic valve support 42 (e.g., upstream
support portion 43 thereof) is provided with one or more (e.g.,
two) control filaments 88 reversibly coupled thereto. Typically,
filaments 88 are coupled to upstream support portion 43 at sites
that are disposed opposite each other around the generally annular
shape of the upstream support portion, and disposed evenly between
holes 82. That is, in the expanded configuration of upstream
support portion 43, a straight line between holes 82 is typically
perpendicular to a straight line between the sites at which
filaments 88 are coupled to the upstream support portion. It should
be noted that other numbers and arrangements of control filaments
may also be used. Typically, each control filament 88 (1) comprises
two portions of a loop of filament that passes through upstream
support portion 43, loops around a downstream surface of the
upstream support portion (i.e., the surface that is placed in
contact with the annulus of the native valve), and passes back
through the upstream support portion, and (2) is decouplable from
the upstream support portion by releasing a first end of the
filament and pulling a second end, thereby unthreading and/or
unlooping the control filament from the upstream support
portion.
[0391] Control filaments 88 facilitate some manipulation of
prosthetic valve support 42 following deployment from delivery tube
80. Typically, control rods 86 further facilitate such
manipulation. State C of FIG. 1C shows such manipulation of
prosthetic valve support 42. For example, it may be desirable to
rotate the prosthetic valve support (e.g., to position and/or
orient the upstream support portion correctly with respect to
native valve 10, to control the order in which different regions of
upstream support portion 43 contact the native valve, and/or to
uncoil control rods 86 and/or control filaments 88 from each
other).
[0392] Reference is now made to FIG. 1D, which show steps in
securing prosthetic valve support 42 against the upstream surface
(e.g., the atrial surface) of native valve 10. Each guide member 56
typically comprises a tether (e.g., a longitudinal member 102), a
pull-wire 104 reversibly coupled to the longitudinal member, and a
tubular member 100 in which the longitudinal member and the
pull-wire are disposed, the tubular member fitting snugly over the
longitudinal member and the pull-wire so as to inhibit the
pull-wire from becoming decoupled from the longitudinal member
(e.g., to maintain a state of coupling therebetween). Pull-wire 104
may or may not be metallic and may have various cross-sectional
shapes (e.g., circular or rectangular). Typically, (1) longitudinal
member 102 defines a loop (e.g., a closed loop) (2) a portion
(e.g., a distal portion) of pull-wire 104 is threaded through the
loop defined by member 102 (e.g., is looped through the loop), and
(3) the snug fitting of tubular member 100 over member 102 and
pull-wire 104 inhibits the portion of the pull-wire from
unthreading from the loop. It is to be noted that, although
longitudinal member 102 is shown as defining a loop that extends
most (e.g., all) of the length of the longitudinal member, the loop
may alternatively be defined only at a proximal end of the
longitudinal member.
[0393] For some applications, longitudinal member 102 and pull-wire
104 are coupled via complementary screw threads. For example,
longitudinal member 102 may comprise, or be coupled to, a screw at
a proximal end thereof, and pull-wire 104 may comprise, or be
coupled to, a socket at a distal end thereof. For some
applications, tubular member 100 is used to decouple (e.g.,
unscrew) pull-wire 104 from longitudinal member 102.
[0394] Tubular member 100 is typically more rigid than pull-wire
104 and/or longitudinal member 102 (although it is still
sufficiently flexible to be transluminally delivered). This
rigidity reduces a likelihood of twisting, kinking, snagging,
and/or other undesirable phenomenon or interactions within the
transluminal delivery system (e.g., within sheath 46, catheter 50,
and/or anchor-delivery tube 52). For some applications tubular
member 100 has a smoother surface than does pull-wire 104 or
longitudinal member 102. For some applications, tubular member 100,
which is necessarily wider than pull-wire 104 and/or longitudinal
member 102, is also more visible using imaging techniques such as
fluoroscopy. This advantageously allows an operating physician to
monitor the intracorporeal juxtaposition of the tubular members
and, if necessary, to intervene, such as by revolving the tubular
members (e.g., proximal ends thereof) around each other.
[0395] As described hereinabove, control rods 86 are used to push
prosthetic valve support 42 toward the annulus of valve 10 by
sliding the control rod over a respective guide member 56 (i.e.,
over the tubular member 100 of the respective guide member). Each
control rod 86 is reversibly coupled at a distal end thereof to a
respective locking member 110 that, in an unlocked state thereof,
is slidable over guide member 56. Thereby, the pushing of
prosthetic valve support 42 is typically performed by pushing with
both control rod 86 and locking member 110. State A of FIG. 1D
shows control rods 86 and respective locking members 110 having
been slid over respective tubular members 100 of respective guide
members 56, such that prosthetic valve support 42 has been pushed
against the annulus of valve 10. Typically, a counter force (e.g.,
a proximal pulling force) is applied to guide member 56 (e.g., to
tubular member 100, longitudinal member 102, and pull-wire 104) so
as to facilitate such sliding.
[0396] State B of FIG. 1D shows tubular member 110 having been
pulled proximally such that the distal end of the tubular member is
disposed proximal to locking member 110, thereby exposing, from the
tubular member, progressive portions of longitudinal member 102, at
least until the tubular member is not disposed between the
longitudinal member and the locking member (e.g., such that the
locking member can directly contact the longitudinal member).
Typically, and as shown in state B of FIG. 1D, tubular member 100
is pulled proximally such that the distal end thereof is disposed
distal to the point at which longitudinal member 102 and pull-wire
104 are coupled, thereby retaining the coupling therebetween. While
in this state, locking member 110 is locked to longitudinal member
102 (e.g., to a portion of the longitudinal member that is disposed
within a channel of the locking member). For some applications,
locking member 110 locks automatically in response to withdrawal of
tubular member 100. For some applications, locking of locking
member 110 is independent of the withdrawal of the tubular member.
An embodiment of locking member 110 and control thereof is
described in more detail hereinbelow with respect to FIGS. 4A-C. It
is to be noted that the scope of the invention also comprises the
use of other locking members such as crimp-based locking members,
and also comprises other locking techniques such as tying.
[0397] Subsequently, and as shown in state C of FIG. 1D, tubular
member 100 is pulled further proximally, such that the distal end
of the tubular member is disposed proximal to the point at which
longitudinal member 102 and pull-wire 104 are coupled, such that
the pull-wire is decouplable from the longitudinal member (e.g.,
unthreadable from the loop defined by the longitudinal member).
[0398] Typically, anchors 48 and longitudinal members 102 are
configured to withstand a pulling force of at least 500 g, so as to
withstand forces within the beating heart. The apparatus is
typically configured such that a pulling force required to pull
tubular member 100 proximally, is less than 500 g, such as less
than 300 g. For some applications, such a configuration is achieved
at least in part by reducing friction between tubular member 100
and pull-wire 104, such as by thermally treating the pull-wire
104.
[0399] Subsequently, control rod 86, tubular member 100, and
pull-wire 104 are pulled proximally, as shown in state D of FIG.
1D, thereby separating the control rod from locking member 110, and
the pull-wire from longitudinal member 102. In order for control
rod 86 to be pulled proximally, the control rod is decoupled from
locking member 110 prior to said pulling. For some applications,
the decoupling of control rod 86 from locking member 110 is
synchronous with the locking of the locking member (e.g., the same
action locks the locking member and decouples the control rod from
the locking member, such as described hereinbelow with respect to
FIGS. 4A-C). For some applications, the decoupling of the control
rod from the locking member is independent of the locking of the
locking member.
[0400] It is to be noted that, as shown in FIG. 1D, for some
applications, prosthetic valve support 42 (e.g., upstream support
portion 43 thereof) is secured to the upstream surface of the
annulus of native valve 10, only by anchors 48 that are anchored to
tissue in ventricle 8 of the subject. It is also to be noted that
prosthetic valve support 42 is coupled to longitudinal members 102
in atrium 6 of the subject. Typically, a distance L1 between each
anchor 48 and the point of upstream support portion 43 to which it
is coupled (e.g., to a respective hole 82 and/or locking member
110) is greater than 0.5 cm, e.g., greater than 1 cm, such as
greater than 2 cm. That is, the length of each longitudinal member
102 that is disposed between a respective anchor and upstream
support portion 43 is typically greater than 0.5 cm, e.g., greater
than 1 cm, such as greater than 2 cm. The length of each
longitudinal member 102 that is disposed between the respective
anchor and the upstream support portion is typically less than 10
cm (e.g., less than 7 cm, such as less than 5 cm). Thereby, the
ventricular sites at which anchors 48 are anchored are typically
more than 0.5 cm (e.g., more than 1 cm, such as more than 2 cm)
away from prosthetic valve support 42.
[0401] Reference is now made to FIG. 1E-F, which show steps in the
delivery and implantation of prosthetic valve 44 at native valve
10, facilitated by prosthetic valve support 42. Prosthetic valve 44
is advanced in a delivery configuration (e.g., in a compressed
state), through sheath 44, typically within a delivery tube 120.
Prosthetic valve 44 comprises a stent-like valve body 122,
typically comprising an expandable frame that typically contains a
shape-memory material such as nitinol. Valve body 122 is shaped to
define a lumen therethrough, and an inner surface of the valve body
is typically lined with a covering, such as a fabric. One or more
prosthetic valve members (not shown for clarity), such as
prosthetic leaflets, are coupled to valve body 122 and disposed
within the lumen thereof.
[0402] Prosthetic valve 44 further comprises one or more
tissue-engaging elements 124. Typically, and as shown, valve 44
comprises two tissue-engaging elements 124 coupled to valve body
122 at sites that are on opposite sides of the circumference of the
valve body. Each tissue-engaging element 124 typically comprises
two arms 126 (e.g., a first clip arm 126a and a second clip arm
126b). For some applications, and as shown, each arm 126 defines an
arc that is coupled to valve body 122 at the base of the arc. For
example, and as shown, each arm 126 may comprise a single arc of
the same shape-memory material as the frame of valve body 122. For
some applications, one or both arms 126 of each tissue-engaging
element 124 may be covered in a covering, such as a fabric.
[0403] When valve 44 is in the compressed state thereof within
delivery tube 120, arms 126 are held against valve body 122 with a
tip 127 of each arm disposed proximally to a site at which that arm
is coupled to the valve body. Each tissue-engaging element 124 is
configured such that a tip 127a of arm 126a is disposed distal to a
tip 127b of arm 126b. For example, arm 126a may be shorter than arm
126b. Alternatively or additionally, arm 126a may be coupled to
valve body 122 at a site that is distal to a site at which arm 126b
is coupled to the valve body.
[0404] Prosthetic valve 44, within delivery tube 120, is advanced
distally between leaflets 14 of native valve 10, and the prosthetic
valve is progressively advanced distally out of a distal end of the
delivery tube, as shown in states A-B of FIG. 1E. It is to be noted
that leaflets 14 typically continue to function following
implantation of prosthetic valve support 42, and may further
continue to function while delivery tube 120 is disposed
therebetween; the leaflets typically coapt around the delivery
tube. At a given degree of advancement of prosthetic valve 44 out
of delivery tube 120, first arm 126a is deployed: tip 127a of each
first arm 126a becomes exposed from the delivery tube and each arm
126a responsively deflects radially outward from valve body 122,
toward a pre-set position (state B of FIG. 1E). Tip 127b of each
arm 126b remains within delivery tube 120. Throughout the
procedure, as distal portions of valve body 122 are progressively
exposed from delivery tube 120, they typically automatically expand
toward an expanded state
[0405] Subsequently, and as shown in state D of FIG. 1E, prosthetic
valve 44 and delivery tube 120 are moved proximally (e.g.,
atrially) such that arm 126a of each tissue-engaging element 124
engages (e.g., captures) a leaflet 14 of native valve 10, e.g.,
such that a portion of each leaflet is disposed between (1) each
arm 126a and (2) a respective second arm 126b and valve body 122.
Optionally, subsequently to deployment of first arm 126a and prior
to moving prosthetic valve 44 proximally, the first arm is
deflected further from valve body 122 than its pre-set position by
applying a force to the first arm using the delivery tube. That is,
an angle between the first arm and an outer surface of the valve
body is increased by applying the force to the first arm using the
delivery tube.
[0406] Typically, the force is applied by moving delivery tube 120
distally with respect to the prosthetic valve (e.g., sliding the
delivery tube over at least part of the prosthetic valve), so as to
push the arm, as shown in state C of FIG. 1E. It is hypothesized
that such "opening" of tissue-engaging element 124 facilitates
engagement of leaflets 14 (e.g., engagement of a larger portion of
leaflets 14). Subsequently, delivery tube 120 is returned
proximally with respect to prosthetic valve 44, such that arm 126a
returns toward its pre-set position (state D of FIG. 1E). For some
applications, until at least the step shown in state D of FIG. 1E,
prosthetic valve 44 is retrievable into delivery tube 120 and
removable from the body of the subject, e.g., as described
hereinbelow with respect to FIG. 2.
[0407] Subsequently, delivery tube 120 is pulled further proximally
with respect to prosthetic valve 44, such that tip 127b of second
arm 126b of each tissue-engaging element 124 becomes exposed from
the delivery tube, and each arm 126b responsively deflects radially
outward from valve body 122, toward a pres-set position (state A of
FIG. 1F), thereby coupling the tissue-engaging element to the
leaflet by sandwiching a portion of a leaflet 14 between the first
and second arms of each tissue-engaging element. Second arm 126b is
typically configured, when completely unrestricted (e.g., in the
absence of leaflet 14) to have a pre-set position that is close to
that of first arm 126a, planar with that of first arm 126a, and/or
further from valve body 122 than is arm 126a. For some
applications, the difference in size and/or position of the arc of
second arm 126b to that of first arm 126a facilitates the second
arm to move into plane with, and/or beyond the plane of, the first
arm.
[0408] Subsequently, prosthetic valve 44 is fully deployed by a
proximal end of the prosthetic valve (e.g., valve body 122 thereof)
being exposed from delivery tube 120 (e.g., by further withdrawing
the delivery tube proximally with respect to the prosthetic
valve)(state C of FIG. 1F). The proximal end of prosthetic valve 44
responsively (e.g., automatically) expands toward the expanded
state thereof. Expansion of the prosthetic valve (e.g., of valve
body 122 thereof) applies a radially-expansive force against
prosthetic valve support 42 (e.g., against an inner perimeter of
upstream support portion 43 thereof), thereby coupling the
prosthetic valve to the prosthetic valve support. Typically,
prosthetic valve support 42 (e.g., the inner perimeter of upstream
support portion 43) restricts expansion of prosthetic valve 44, at
least in part.
[0409] For some applications, and as shown in state B of FIG. 1F,
subsequently to the coupling of tissue-engaging elements 124 to
leaflets 14, and prior to coupling of prosthetic valve 44 to
prosthetic valve support 42, the prosthetic valve is pulled
proximally, e.g., so as to align a portion of valve body 122 with
upstream support portion 43 and/or to drawn leaflets 14 toward the
upstream support portion.
[0410] It is to be noted that, for some applications, each
tissue-engaging element 124 comprises only one arm 126. For some
such applications, the one arm 126 comprises and/or functions like
first arm 126a described herein. For some such applications, the
one arm 126 is configured to couple to the leaflet by sandwiching a
portion of the leaflet between the one arm and valve body 122. For
some such applications, the one arm 126 is configured, when the
prosthetic valve is pulled proximally as shown in state B of FIG.
1F, to sandwich a portion of the leaflet between the one arm and
prosthetic valve support 42 (e.g., upstream support portion 43
thereof).
[0411] State D of FIG. 1F shows the implanted (e.g., final) state
of prosthetic valve support 42 and prosthetic valve 44, following
implantation thereof at native valve 10. For some applications, in
this implanted state, prosthetic valve support 42 and prosthetic
valve 44 are inhibited from moving upstream (e.g., atrially) both
by tissue anchors 48 and by tissue-engaging elements 124. That is,
for some applications, resistance to forces on support 42 and valve
44 from the functioning of the heart of the subject, is provided in
part by anchors 48 and in part by elements 124. For some
applications, in this implanted state, prosthetic valve support 42
and prosthetic valve 44 are inhibited from moving upstream mostly
(e.g., solely) by tissue-engaging elements 124. That is, for some
applications, resistance to forces on support 42 and valve 44 from
the functioning of the heart of the subject, is provided mostly
(e.g., solely) by elements 124. For some such applications, anchors
48 and longitudinal members 102 are thereby only required until
prosthetic valve 44 has been implanted. It is to be noted that in
both cases, prosthetic valve support 42 (e.g., upstream support
portion 43 thereof) inhibits movement ventricularly of prosthetic
valve 44, and of the prosthetic valve support itself.
[0412] Reference is again made to FIGS. 1D-F. For some
applications, locking of locking members 110 to longitudinal
members 102 and/or decoupling of pull-wires 104 from longitudinal
members 102 (FIG. 1D) is not performed until after implantation of
prosthetic valve 44 (FIGS. 1E-F). For such applications, it is
thereby possible to adjust the length of the portion of
longitudinal members 102 (e.g., tension on the longitudinal
members) after implantation of prosthetic valve 44. For some
applications, a similar advantage is conferred by locking members
being reversibly lockable, being locked before implantation of
prosthetic valve 44, and subsequently to implantation of the
prosthetic valve, being unlocked to allow re-adjustment of
longitudinal members 102.
[0413] Reference is again made to FIGS. 1A-F. For some
applications, anatomical dimensions of native valve 10 and/or
surrounding tissues are determined (e.g., measured), and prosthetic
valve support 42 and/or prosthetic valve 44 are selected
accordingly (e.g., from a selection of prosthetic valve supports
and/or prosthetic valves of different sizes). For example, an
optimal lumen size (e.g., transverse cross-sectional area) for a
prosthetic valve may be determined according to an area of the
lumen defined by the annulus of the native valve of the subject.
Responsively, a prosthetic valve having a lumen of that particular
size may be selected. Similarly, a prosthetic valve support having
an inner perimeter that defines an opening having a particular
cross-sectional area may be selected, so as to restrict the
expansion of a prosthetic valve to have a lumen of that particular
size. Alternatively or additionally, a prosthetic valve support
having an outer perimeter of a particular size may be selected
according to determined dimensions of the annulus of the valve
and/or walls of the atrium. It is to be noted that selecting a size
according to determined anatomical dimensions may only in some
cases comprise selecting a size that matches the anatomical
dimensions. For example, an optimal size for the transverse
cross-sectional area of a prosthetic valve is typically less than
90% of the area defined by the annulus of the native valve, so as
to allow the leaflets of the native valve to coapt around the
prosthetic valve and facilitate sealing.
[0414] Because prosthetic valve support 42 is typically implantable
without eliminating functioning of the native leaflets, for some
applications, the prosthetic valve support is implantable without
the use of cardiopulmonary bypass. For some applications,
prosthetic valve 44 is also implantable without the use of
cardiopulmonary bypass.
[0415] Reference is made to FIG. 2, which is a schematic
illustration of prosthetic valve 44 being retrieved into delivery
tube 120, in accordance with some applications of the invention. As
described hereinabove, for some applications, until at least the
step shown in state D of FIG. 1E, prosthetic valve 44 is
retrievable into delivery tube 120 and removable from the body of
the subject. Delivery tube 120 is moved distally with respect to
prosthetic valve 44, in a manner similar to that used to push arms
127a, described with reference to FIG. 1E (state C), but such that
delivery tube 120 is slid over the site at which arms 127a are
coupled to valve body 122, thereby pushing arms 127a to deflect
distally. Prosthetic valve 44, including at least part of arms
127a, is drawn into delivery tube 120 (e.g., by sliding the
prosthetic valve distally and/or the delivery tube proximally), and
is typically subsequently removed from the body of the subject.
[0416] Reference is made to FIGS. 3A-C, which are schematic
illustrations of the introduction of guide members 56 through
prosthetic valve support 42 and delivery tube 80, in accordance
with some applications of the invention. As described hereinabove
(e.g., with reference to FIG. 1C), prosthetic valve support 42 is
slidable toward native valve 10, over guide members 56, including
while the prosthetic valve support is compressed within delivery
tube 80. Following coupling of anchors 48 to the ventricular sites,
guide members 56 extend from the anchors to outside of the body of
the subject, and have respective free proximal ends 57. Before
introduction of support 42 within tube 80 into the body of the
subject (e.g., into sheath 46), guide members 56 are threaded
through holes 82 in upstream support portion 43 of prosthetic valve
42, and through delivery tube 80, e.g., by the operating
physician.
[0417] Typically, prosthetic valve support 42 is provided in the
compressed state thereof, within delivery tube 80, e.g., as a unit
140, coupled to a distal end of a controller 142 that is used to
move the unit transluminally (e.g., within sheath 46). Unit 140
comprises (e.g., is provided having) one or more introducer tubes
144, each introducer tube being shaped to define a lumen
therethrough, and having an open distal end 143 and an open
proximal end 145. Distal end 143 of each tube is disposed outside a
distal end of support 42 and/or tube 80, and proximal end 145 of
each tube is disposed outside a proximal end of the support and/or
tube 80. Each introducer tube 144 passes (1) from the distal end
thereof, (2) through a respective hole 82 in upstream support
portion 43 from the downstream surface of the support portion
(which defines an outer surface of the support portion in the
compressed state thereof) to an upstream surface of the support
portion (which defines an inner surface of the support portion in
the compressed state thereof), and (3) to the proximal end
thereof.
[0418] As shown in FIG. 3A, free proximal end 57 of each guide
member 56 is advanced through a respective introducer tube 144,
thereby threading the guide member through upstream support portion
43 of prosthetic valve support 42. Typically, and as shown in FIG.
3B, introducer tubes 144 are subsequently removed, prior to
introduction of unit 140 into the body of the subject. That is,
introducer tubes 144 are typically temporary. FIG. 3C shows
upstream support portion 43 of prosthetic valve support 42 having
been partially exposed from delivery tube 80, in order to
illustrate the resulting threading of guide members 56 through
upstream support portion 43.
[0419] Reference is made to FIGS. 4A-C, which are schematic
illustrations of locking member 110, and control thereof, in
accordance with some applications of the invention. As described
hereinabove, locking member 110 is slidable over guide member 56
(e.g., over tubular member 100 thereof). As also described
hereinabove, locking member 110 is configured to lock to
longitudinal member 102.
[0420] FIG. 4A shows locking member 110 in the unlocked state
thereof, in which the locking member typically defines a channel
therethrough through which tubular member 100 and longitudinal
member 102, either within the tubular member or outside of the
tubular member, are slidable. The channel of locking member 110 is
defined by a generally tubular portion 160 of the locking member.
Tubular portion 160 defines one or more, such as two, oblique slits
162 in the lateral walls thereof. Locking member 110 comprises
locking element, such as a locking bar 164, that is disposed
generally orthogonally to the channel of the locking member, and
passes through the slits (e.g., through both slits) of the tubular
member. When locking bar 164 is slid distally and/or proximally,
the locking bar thereby moves across at least part of the channel
defined by tubular portion 160. Locking member 110 further
comprises a spring 166 that is configured to push locking bar 164
in a given direction (e.g., distally), thereby transitioning the
locking member into the locked configuration thereof (i.e., locking
the locking member)(FIG. 4B).
[0421] Locking member 110 is typically controllable using a holding
member 112 that inhibits (e.g., prevents) the locking member from
locking, such as by inhibiting movement of locking bar 164. As
described hereinabove, each control rod 86, used to push prosthetic
valve support 42 toward the annulus of valve 10, is reversibly
coupled at a distal end thereof to a respective locking member 110,
such that the pushing is typically performed by pushing with
control rod 86 and locking member 110. For some applications, and
as shown in FIGS. 4A-C, holding member 112 comprises and/or is
defined by control rod 86. For such applications, control rod 86
defines one or more slits 168 in a lateral wall thereof (e.g., two
slits 168 on opposite sides of the lateral wall of the control
rod). Typically, slits 168 are L-shaped, thereby providing (1) a
holding region 170 that is generally orthogonal to the
proximal-distal (e.g., longitudinal) axis of control rod 86, and
(2) a release region 172 that is generally parallel with the
proximal-distal axis of the control rod, and that is open to the
distal end of the control rod. Locking bar 164 is configured such
that ends thereof extend at least into (e.g., through) slits
168.
[0422] In the unlocked state in which locking member 110 is
advanced over guide member 56 toward upstream support portion 43
and the annulus of the native valve, the ends of locking bar 164
are disposed in holding region 170 of each slit 168, and the
locking bar is thereby inhibited from moving distally and locking
the locking member (FIG. 4A). In order to lock the locking member,
control rod 86 is rotated with respect to locking member 110, such
that the ends of locking bar 164 move into release region 172 of
each slit 168. In this position, spring 166 is thereby able to move
locking bar toward the distal end of release region 172, thereby
locking the locking member (FIG. 4B).
[0423] As described hereinabove, tubular member 100 is typically
withdrawn from locking member 110 before the locking member is
locked, and the locking member is locked to longitudinal member
102, e.g., by locking bar 164 sandwiching longitudinal member 102
against the inner surface of the channel of the locking member
(e.g., effectively narrowing the channel at the site of the locking
bar). Movement of the ends of locking bar 164 into and through
release region 172 also decouples control rod 86 from the locking
member, allowing the control rod to be removed from the body of the
subject (typically along with tubular member 100)(FIG. 4C). For
some applications, longitudinal member 102 comprises suture. For
some applications, long member 102 comprises a polymer, such as
polyester. For some applications, longitudinal member 102 comprises
a metal. For example, the longitudinal member may comprise one or
more wires, such as a plurality of wires twisted or braided into a
cable. It is hypothesized that for some applications, a metallic
composition reduces compressibility of longitudinal member 102
and/or facilitates locking of locking member 110 to the
longitudinal member.
[0424] It is to be noted that locking member 110 thereby (1) when
unlocked, facilitates sliding therethrough of a relatively wide
element, tubular member 100, and (2) when locked, locks to a
relatively narrow element, longitudinal member 102. To facilitate
this, between the locked and unlocked states, locking bar 164
thereby moves a sufficient distance across the channel defined by
locking member 110. That is, locking bar 164 moves a larger
distance than would be necessary to lock a similar locking member
that does not facilitate, in the unlocked state thereof, sliding
therethrough of a tubular member that is wider than the
longitudinal element.
[0425] Reference is again made to FIGS. 1D and 4A-C. It is to be
noted that locking member 110 is typically configured to lock to
longitudinal member 102 independently of (e.g., in the absence of)
a complementary element, such as teeth, on the longitudinal member.
For some applications, locking member 110 is configured to be
coupled to any part of longitudinal member 102.
[0426] Reference is made to FIG. 5, which is a schematic
illustration of steps in the delivery of tissue anchors 48 to
ventricle 8, and anchoring of the anchors in the ventricle, in
accordance with some applications of the invention. For some
applications, the steps shown in FIG. 5 (and/or states A-D thereof)
can be used in place of the steps shown in FIG. 1B (and/or states
A/D thereof), mutatis mutandis (e.g., after the steps shown in FIG.
1A and/or before the steps shown in FIG. 1C). FIG. 1B shows one
delivery catheter 50 being used to deliver both anchors 48, and
when delivering second tissue anchor 48b, anchor-delivery tube 52
fitting alongside first guide member 56a within catheter 50. As
stated hereinabove, for some applications, a separate catheter is
used for each anchor. FIG. 5 shows one such application.
[0427] Typically, first anchor 48a is delivered and anchored as
described hereinabove with reference to FIG. 1A, wherein catheter
50 in FIG. 1A comprises a first catheter 50a. Subsequently, and as
shown in FIG. 5, a second catheter 50b is advanced through sheath
46, such that second catheter 50b is disposed alongside first guide
member 56a within sheath 46. It is to be noted that, in both FIG.
1B and FIG. 5, two anchors 48 are anchored at respective
ventricular sites, and two respective guide members 56, extend from
the anchors, through atrium 6, and typically out of the body of the
subject.
[0428] Reference is made to FIG. 6, which is a schematic
illustration of a system 180 for use with prosthetic valve support
42, in accordance with some applications of the invention. For such
applications of the invention, prosthetic valve support 42 is
slidable toward native valve 10 over guide members 56, including
while the prosthetic valve support is compressed within delivery
tube 80. Following coupling of anchors 48 to the ventricular sites,
guide members 56 extend from the anchors to outside of the body of
the subject, and have respective free proximal ends 57. Before
introduction of support 42 within tube 80 into the body of the
subject (e.g., into sheath 46), guide members 56 are threaded
through holes 82 in upstream support portion 43 of prosthetic valve
42, and through delivery tube 80, e.g., by the operating
physician.
[0429] FIGS. 3A-C and the descriptions thereof describe prosthetic
valve support 42 being provided as a unit 140 comprising introducer
tubes 144, which are removed subsequently to advancement of guide
members 56 through upstream support portion 43 and prior to
introduction of the unit into the body of the subject. FIG. 6 shows
system 180, in which prosthetic valve support is provided within
delivery tube 80, e.g., as a unit 182, coupled to a distal end of
controller 142, described hereinabove.
[0430] Unit 182 comprises (e.g., is provided having) one or more
introducer tubes 184, each introducer tube being shaped to define a
lumen therethrough, and having an open distal end 183. Distal end
183 of each tube is disposed outside a distal end of support 42
and/or tube 80, and each introducer tube 184 extends out of a
proximal end of the support and/or tube 80. Similarly to unit 140
described with reference to FIGS. 3A-C, each introducer tube 144 of
system 180 passes from the distal end thereof, through a respective
hole in upstream support portion 43 from the downstream surface of
the support portion (which defines an outer surface of the support
portion in the compressed state thereof) to an upstream surface of
the support portion (which defines an inner surface of the support
portion in the compressed state thereof). In contrast to unit 140,
introducer tubes 184 extend from a proximal end of delivery tube 80
to a proximal end portion of the apparatus. In further contrast to
unit 140, tubes 184 remain in place as unit 182 is advanced
transluminally over guide members 56. Tubes 184 are typically
flexible to facilitate transluminal advancement thereof.
[0431] A locking member 190 is disposed over each introducer tube
184, such that the introduction of guide member 56 through the
introducer tube also introduces the guide member through the
locking member. Locking member 190 is slidable over guide member 56
(e.g., over tubular member 100 thereof), and is configured to lock
to longitudinal member 102. Typically, locking member 190 is
identical to locking member 110, described hereinabove, except that
locking member 190 is configured (e.g., dimensioned) to be slidable
also over introducer tube 184. Each locking member 190 is disposed
at the distal end of a respective tubular control rod 192, which is
typically identical to control rod 86, described hereinabove,
except that control rod 192 is configured (e.g., dimensioned) to be
slidable also over introducer tube 184.
[0432] The use of system 180, including introducer tubes 184,
advantageously (1) removes the requirement for two separate
introductions of proximal end 57 of guide member 56 (i.e., through
an introducer tube and subsequently through a locking member and
control rod); and (2) facilitates control rods 192 (and locking
members 190) being present in the atrium of the subject during
expansion of prosthetic valve support 42, thereby reducing an
interval between the expansion of the prosthetic valve support and
pressing of the prosthetic valve support against the annulus of the
native valve.
[0433] Reference is made to FIGS. 7A-C, which are schematic
illustrations of a system 200 for facilitating transluminal
delivery of a prosthetic valve assembly 202, in accordance with
some applications of the invention. FIG. 7A shows prosthetic valve
assembly 202 in an expanded state thereof. Prosthetic valve
assembly comprises (1) a prosthetic valve body 204, which comprises
a first frame 206 (e.g., a wire frame), and is shaped to define a
lumen 208 therethrough, (2) an annular upstream support 210, which
comprises a second frame 212 (e.g., a wire frame), is shaped to
define an opening through the upstream support, and is configured
to be placed against an upstream surface (e.g., an atrial surface)
of native valve 10 (e.g., of an annulus thereof), and (3) a
flexible sheet 214 that couples the first frame to the second
frame. In the expanded state of assembly 202 (and thereby of body
204), frame 206 of body 204 is generally cylindrical, and has a
diameter d1. In the expanded state of assembly 202 (and thereby of
upstream support 210), frame 212 of support 210 is typically
generally annular, and has an outer perimeter 213 that has a
diameter d2, which is greater than diameter d1.
[0434] Sheet 214 may be a fabric, a film, and/or another sheet-like
structure, and may comprise a natural material, a polymer, a
biomaterial, and/or any other suitable material. Typically, sheet
214 comprises polyester, PTFE, and/or pericardial tissue.
[0435] For some applications, and as shown in FIG. 7A, in the
expanded state of assembly 202, and in the absence of external
forces (e.g., if the assembly were resting on a table surface),
sheet 214 is generally annular and flat, and an upstream end 218 of
frame 206 is disposed generally on a plane defined by support 210.
For such applications, an inner perimeter 211 of frame 212 defines
an opening that has a diameter d3 that is greater than diameter
d1.
[0436] For some applications, in such an expanded and unconstrained
state, sheet 214 is generally frustoconical or funnel-shaped, and
upstream end 218 of frame 206 is disposed below the plane defined
by support 210. (For some such frustoconical or funnel-shaped
arrangements, the sheet may also be considered to be annular.)
[0437] For some applications, in such an expanded and unconstrained
state, sheet 214 is generally tubular, upstream end 218 of frame
206 is disposed below the plane defined by support 210. For such
applications, diameter d3 is typically generally equal to diameter
d1.
[0438] Typically, one or both of frames 206 and 212 is covered on
at least one side by a covering 220. For some applications, sheet
214 comprises a portion of covering 220, e.g., the sheet is defined
by a portion of the covering that is disposed between frames 206
and 212. For some applications, and as shown in FIG. 7A, covering
220 is disposed (1) on a tissue-facing side of frame 212 (e.g.,
defines a tissue-contacting surface of support 210), and (2) on an
inner surface of frame 206 (i.e., lines the frame, and defines
lumen 208).
[0439] A valve member 205 (e.g., comprising one or more prosthetic
leaflets; shown in FIGS. 8D-G) is coupled to frame 206, is disposed
within lumen 208, and provides valve (e.g., one-way) functionality
to assembly 202. Valve member 205 may alternatively or additionally
comprise a different valve member, such as a mechanical valve
member.
[0440] At least two eyelets 222 are disposed on an outer surface of
body 204 (i.e., protrude radially outward from body 204).
Typically, eyelets 222 are pivotably coupled to body 204, e.g.,
such that the eyelets can pivot (e.g., rotate) in both directions
by at least 5 degrees (e.g., more than 5 degrees and/or less than
90 degrees, such as between 5 and 90 degrees, e.g., between 5 and
60 degrees, such as between 5 and 45 degrees). For some
applications, the eyelets can pivot in a plane parallel to a plane
defined by a tangent of the valve body at the site to which the
eyelet is coupled, as shown in the blowup box. Alternatively or
additionally, the eyelets can pivot in a plane that is orthogonal
to the plane defined by the tangent, e.g., such that the eyelets
can point toward and/or away from the valve body. For some
applications, eyelets 222 are sutured to body 204. Eyelets 222 are
arranged in at least one pair; each eyelet of the pair being
disposed on the opposite side of body 206 from the other eyelet of
the pair.
[0441] FIG. 7B shows system 200 in a delivery configuration
thereof. System 200 comprises a delivery tool 230, which comprises
a first housing 232 (e.g., a proximal housing) and a second housing
234 (e.g., a distal housing), which are articulatably coupled to
each other via a flexible control rod assembly 240 disposed through
the housings.
[0442] In the delivery configuration of system 200, assembly 202 is
in a compressed state thereof, in which prosthetic valve body 204
(in a compressed state thereof) is generally cylindrical, and
upstream support 210 (in a compressed state thereof) is also
generally cylindrical. Typically, in the delivery configuration of
system 200, sheet 214 is also generally cylindrical. Assembly 202,
in the compressed configuration thereof, (1) has a central
longitudinal axis, at one zone (e.g., at one end) of which body 204
is disposed, and at another zone (e.g., the other end) of which
support 210 is disposed, and (2) defines an articulation zone 236
in which (a) at least part of sheet 214 is disposed, and (b)
neither frame 206 of body 204 nor frame 212 of support 210 is
disposed, and about which body 204 and support 210 are
articulatable with respect to each other.
[0443] In the delivery configuration of system 200, at least part
of support 210 is disposed within housing 232 (which maintains the
at least part of the support in the compressed state thereof), and
at least part of body 204 is disposed within housing 234 (which
maintains the at least part of the support in the compressed state
thereof). Housing 232 defines an orifice 233 through which support
210 is introducible into the housing, and removable from the
housing. Housing 234 defines an orifice 235 that faces orifice 233,
and through which body 204 is introducible into the housing, and
removable from the housing. In the delivery configuration, eyelets
222 protrude radially outward beyond the surface of delivery tool
230 (e.g., beyond a lateral wall of housing 234). Typically,
housing 234 (e.g., the lateral wall thereof) is shaped to define a
respective slit 237 for each eyelet, through which the eyelet
protrudes beyond the surface of the housing. Each slit 237 is
continuous with (i.e., is in communication with) orifice 235 such
that, as described hereinbelow, during deployment of valve body
204, eyelet 222 can slide out of the slit at the orifice.
[0444] In the delivery configuration of system 200, tool 230 is in
a contracted state, in which housing 232 is disposed at a distance
d4 from housing 234 (e.g., orifice 233 is disposed at distance d4
from orifice 235). Distance d4 is typically greater than 1.5 mm
and/or less than 30 mm, such as between 1.5 mm and 30 mm (e.g.,
between 10 and 15 mm). In this state, at least part of sheet 214 is
exposed between the housings. The at least part of sheet 214 (and
thereby of articulation zone 236) that is exposed between housings
232 and 234 facilitates articulation of housing 234 containing body
204 with respect to housing 232 containing support 210, and thereby
defines an articulation zone 238 of system 200 in the delivery
configuration thereof. Typically at least part of control rod
assembly 240 is flexible, so as to facilitate articulation at
articulation zone 238. For example, although assembly 240 as a
whole is typically sufficiently flexible so as to facilitate its
transluminal delivery to the heart, control rods 244 and 246 may be
more flexible than control rod 240 (e.g., more flexible than
required for transluminal delivery to the heart alone), so as to
facilitate articulation at articulation zone 238. For some such
applications, respective portions of control rods 244 and 246 that
are disposed within articulation zone 238 when tool 230 is in the
contracted state (FIG. 7C) are more flexible than adjacent portions
of the control rods (e.g., portions disposed within housings 232
and 234 when tool 230 is in the contracted state). For example, and
as shown, a portion 245 of control rod 244 may be narrower than
adjacent portions of the control rod.
[0445] Control rod assembly 240 comprises (1) a first
housing-control rod 242, coupled to first housing 232, (2) a second
housing-control rod 244, coupled to second housing 234, and (3) a
prosthesis-control rod 246, coupled to a mount 248 that is
reversibly couplable to valve assembly 202, e.g., via a plurality
of recesses 250 in the mount which receive respective portions of
assembly 202. Typically, assembly 202 is couplable to mount 248 by
valve body 204 being coupled to the mount, and further typically by
a plurality of protrusions 252 of frame 206 being disposed within
respective recesses 250. Housing 234 retains this coupling by
inhibiting body 204 from expanding radially away from mount
248.
[0446] Typically, at least part of second housing-control rod 244
is disposed within and slidable through prosthesis-control rod 246,
and at least part of the prosthesis-control rod is disposed within
and slidable through first housing-control rod 242 (e.g.,
coaxially).
[0447] System 200 (e.g., tool 230 thereof) further comprises at
least two flexible reference-force tubes 260, which extend, (a)
from a proximal end of the system (e.g., from an extracorporeal
portion of the system, such as from a handle of tool 230), (b)
through a proximal end of housing 232, (c) through a lumen 254
defined by support 210 in the compressed state thereof, (d) through
sheet 214, (e) along the outside of at least part of body 204, and
typically (f) until a distal portion of body 204. A locking member
262 is disposed between each eyelet 222 and a respective tube 260.
Typically, locking members 262 are not directly coupled to body
204, but are instead each held in position between eyelet 222 and
tube 260 by a guide member 256 being disposed through the eyelet,
the tube, and the locking member. For some applications, locking
member 262 is integral with eyelet 222 (e.g., eyelet 222 is
configured to and/or shaped to define locking member 262).
[0448] For some applications, guide members 256 are identical to
guide members 56, described hereinabove. Guide members 256 are
described in more detail hereinbelow.
[0449] Reference is now made to FIGS. 8A-H, which are schematic
illustrations of a technique for use with system 200, to
transluminally implant prosthetic valve assembly 202, in accordance
with some applications of the invention. Typically, sheath 46 is
advanced transluminally (e.g., transfemorally) to right atrium 12
of heart 4, through the fossa ovalis, and into left atrium 6 using
standard transseptal techniques, as described hereinabove with
reference to FIGS. 1A-B. Subsequently, first tissue anchor 48a and
second tissue anchor 48b are anchored at respective ventricular
sites, e.g., as described with reference to FIGS. 1A-B and/or 5,
mutatis mutandis.
[0450] A guide member 256 is coupled to each tissue anchor (e.g.,
the tissue anchors are provided pre-coupled to the guide members),
such that after anchoring of the tissue anchors, each guide member
extends from the anchor, out of the body of the subject, e.g., as
described hereinabove with respect to guide member 56, mutatis
mutandis. A proximal end of each guide member 256 is introduced
through a respective eyelet 222, locking member 262, and
reference-force tube 260, such that system 200 appears as shown in
FIG. 7B. As described hereinabove, each guide member 256 typically
holds each locking member 262 in place between its respective
eyelet 222 and reference-force tube 260.
[0451] System 200 (e.g., assembly 202 within delivery tool 230) is
subsequently advanced along guide members 256 and via sheath 46 to
left atrium 6 (FIG. 8A). Once exposed outside of the distal end of
sheath 46, system 200 is guided by guide members 256 generally
toward the ventricular sites at which anchors 48 are anchored.
Articulation of system 200 (e.g., at articulation zone 238, and/or
at another articulation zone 239 proximal to housing 232)
facilitates transluminal advancement of the system past curves in
the vasculature. The articulation also facilitates movement of
system 200 from the distal end of sheath 46 and between leaflets 14
of valve 10, e.g., by facilitating steering of the system along a
path defined by guide members 256. This steering is typically
further facilitated by (1) the position of eyelets 222 at a distal
portion of system 200 (e.g., at a distal portion of housing 234),
which turns the housing in response to encountering a turn in
members 256, and/or (2) the pivotable coupling of eyelets 222 to
body 204, described hereinabove; pivoting of eyelet 222 reduces a
likelihood of the eyelet snagging on guide member 256 when
encountering a turn in the guide member. For some applications,
eyelets 222 are internally coated with a material having a low
coefficient of friction, such as polytetrafluoroethylene, to
further facilitate sliding of the eyelet over guide member 256.
[0452] It is to be noted that, due to the described articulation, a
distance d5 between a proximal end of housing 232 and a distal end
of housing 234 may be greater than for a similar system that does
not articulate. For example, distance d5 may be greater than a
distance d6 along an atrioventricular axis between (a) a height on
the atrioventricular axis of the upstream surface of native valve
10, and (b) a height on the atrioventricular axis of the
transseptal entry point into left atrium 6 (e.g., the fossa
ovalis). For some applications, distance d5 may be greater than the
overall height of left atrium 6. Distance d5 is typically greater
than 25 mm and/or less than 100 mm, such as between 25 mm and 100
mm (e.g., 35-60 mm, such as 40-50 mm).
[0453] Reference is made to FIG. 8B. System 200 is advanced such
that distal housing 234, containing valve body 204 in the
compressed state thereof, passes between leaflets 14 of native
valve 10. Valve body 204 is withdrawn out of orifice 235 of housing
234 by moving control rod 244 with respect to control rod 246. For
example, and as shown in FIGS. 8B-C, control rod 244 (and thereby
housing 234) may be moved distally into ventricle 8, while control
rod 246 (and thereby mount 248 and valve body 204) remains
stationary, thereby increasing the distance between housing 232 and
housing 234.
[0454] When protrusions 252 of frame 206 become withdrawn from
housing 234, the portion of valve body 204 coupled to the mount
expands (e.g., automatically), thereby disengaging the protrusions
from recesses 250 of mount 248, and decoupling the valve body from
the mount (FIG. 8C). For clarity, FIGS. 8C-D show the distal
portion of valve body 204 expanding before the proximal portion of
the valve body. It is to be noted, however, that portions of the
valve body typically expand as they become exposed from housing
234, and therefore the proximal portion of the valve body typically
expands while the distal portion of the valve body is still
disposed within housing 234.
[0455] FIG. 8D shows valve body 204 having been completely removed
from housing 234, and support 210 having been removed from proximal
housing 232 by control rod 242 (and thereby housing 232) being
withdrawn proximally, thereby further increasing the distance
between housing 232 and housing 234. Typically, an opposing
reference force is provided by reference-force tubes 260, so as to
hold assembly 202 in place at the native valve while housing 232 is
withdrawn.
[0456] During the withdrawal of valve body 204 from housing 234,
eyelets 222 typically slide through slits 237, and out of the slits
at orifice 235.
[0457] For some applications, support 210 is deployed from housing
232 before valve body 204 is deployed from housing 234.
[0458] Subsequently, tension is applied to guide members 256 while
an opposing reference force is provided to assembly 202 by tubes
260, thereby reducing a length of each guide member 256 that is
disposed between eyelet 222 and its respective tissue anchor 48
(FIG. 8E). That is, each guide member 256 is slid proximally with
respect to its respective reference-force tube 260. Typically, the
reference-force is provided to assembly 202 by a distal end of each
reference-force tube 260 abutting a respective locking member; the
reference force being transferred via the locking member (and
typically further via eyelet 222 to valve body 204).
[0459] For some applications this tensioning moves valve body 204
at least slightly distally into ventricle 8, such that sheet 214
becomes at least slightly frustoconical (e.g., as shown in FIG.
8E). For some applications this tensioning deforms support 210
and/or deflects the support with respect to body 204, e.g., such
that the support becomes less flat (e.g., less planar). For
example, before tensioning, support 210 may be flat annular (as
shown in FIG. 8D), and after tensioning the support may be
frustoconical (as shown in FIG. 8E). Alternatively, and as
described in more detail with reference to FIGS. 14A-B, mutatis
mutandis, the prosthetic valve assembly may be configured such that
the upstream support is frustoconical before tensioning, and the
tensioning changes a slant of the frustoconical shape. For example,
before tensioning, the upstream support may be frustoconical with
the larger base of the frustum closer to a ventricular end of an
atrioventricular axis than is the smaller base of the frustum, and
after tensioning the support may become flatter, or may even
invert, such that it becomes frustoconical with the smaller base
closer to the ventricular end of the atrioventricular axis (e.g.,
the conformation shown in FIG. 8E, mutatis mutandis).
[0460] For some applications, tensioning is performed before
deployment of support 210 from housing 232.
[0461] Each guide member 256 typically comprises a tether 282
(e.g., a longitudinal member), a pull-wire 284, and a tubular
member 280 in which the pull-wire and the tether are disposed. A
distal portion of pull-wire 284 is reversibly coupled to a proximal
portion of tether 282, and tubular member 280 fits snugly over at
least the distal portion of the pull-wire and the proximal portion
of the tether so as to inhibit the pull-wire from becoming
decoupled from the tether (e.g., to maintain a state of coupling
therebetween). For some applications, and as shown, the reversible
coupling is provided by pull-wire 284 and tether 282 defining
respective mating surfaces. For some applications, the reversible
coupling is provided as described hereinabove for guide member
56.
[0462] When each guide member 256 (e.g., the tether 282 thereof) is
tensioned, the guide member is withdrawn proximally until at least
part of tether 282 (within tubular member 280) is disposed within
locking member 262 (e.g., at least until the proximal portion of
the tether has passed through the locking member; FIG. 8E state
B).
[0463] Reference is now made to FIG. 8F. Once a desired tension is
obtained, the tension is fixed. Tubular member 280 is withdrawn
proximally with respect to tether 282, pull-wire 284 and locking
member 262 (FIG. 8F). State A of FIG. 8F shows tubular member 280
having been withdrawn until eyelet 222. State B of FIG. 8F shows
tubular member 280 having been withdrawn until a distal end of the
tubular member is disposed proximal to locking member 262, thereby
exposing tether 282 to the locking member.
[0464] Typically, locking member 262 is biased (e.g., shape-set) to
assume a locked state, and while tubular member 280 is disposed
within the locking member, the tubular member inhibits locking of
the locking member to tether 282 (or to pull-wire 284), and the
removal of the tubular member from within the locking member
facilitates automatic locking of the locking member to the tether
(i.e., transitioning of the locking member into a locked state).
Tubular member 280 is slidable through locking member 262 despite
such biasing of the locking member, e.g., due to (a) the tubular
member having a smooth surface, and/or (b) the tubular member
retaining locking elements 263 of the locking member at an angle
alpha_1 with respect to the tubular member, which is shallower than
an angle alpha_2 with respect to tether 282 that the locking
elements assume when the tubular element is withdrawn (compare FIG.
8F state A to state B).
[0465] Typically, tether 282 defines a plurality of nodules 286,
which facilitate locking of locking member 262 to the tether. For
some applications, locking elements 263 and nodules 286 function as
a ratchet. For some such applications, subsequently to
transitioning of locking member 262 into the locked state thereof,
one-way movement of tether 282 through the locking member is
possible, thereby facilitating further increase, but not reduction,
of tension.
[0466] Reference is now made to FIG. 8G. Tubular member 280 and
pull-wire 284 are decoupled from tether 282 and prosthetic valve
assembly 202, and delivery tool 230 is withdrawn proximally (e.g.,
into sheath 46, and out of the body of the subject). Typically,
housing 234 and mount 248 are withdrawn via the lumen of valve body
204 (e.g., between the prosthetic leaflets disposed therein). For
some applications, housing 234, rods 244 and 246, and mount 248 are
withdrawn prior to the tensioning step (e.g., prior to withdrawal
of reference-force tubes 260, such as between the step shown in
FIG. 8D and the step shown in FIG. 8E, mutatis mutandis).
[0467] Typically, tubular member 280 and pull-wire 284 are
decoupled from tether 282 by withdrawing the tubular member further
proximally, such that the distal portion of pull-wire 284 and the
proximal portion of tether 282 are exposed from the tubular member
(state A of FIG. 8G). Reference force for this withdrawal is
provided by the anchored tether 282, and optionally also by
reference-force tubes 260. Tubular member 280, pull-wire 284, and
reference-force tube 260 are then withdrawn (state B of FIG.
8H).
[0468] FIG. 8H is a schematic illustration of prosthetic valve
assembly 202 following implantation at native valve 10 of heart 4.
Assembly 202 provides replacement one-way valve functionality in
which blood flows from atrium 6, through the opening defined by
upstream support 210, past sheet 214, through lumen 208 of valve
body 204, and into atrium 8. Sheet 214 thereby defines and/or
serves as a conduit that provides fluid communication between the
opening defined by upstream support 210 (e.g., by frame 212
thereof) and lumen 208 of valve body 204. Further typically, this
conduit is uninterrupted except for holes (not shown) that may
remain where reference-force tubes 260 originally extended through
the sheet.
[0469] Regurgitation through these holes is typically minimal or
absent due to their small size. The holes may be slit-like (rather
than punched holes), such that in the absence of reference-force
tubes 260 the holes become generally closed. Additionally,
coaptation of leaflets 14 and tissue growth over the holes may
further facilitate sealing. Alternatively or additionally, the
holes may be defined by tubular protrusions 215 that extend from
sheet 214 (shown in the "optional" box, FIG. 7B). Tubular
protrusions 215 may comprise the same material as sheet 214, or may
comprise a different material. Tubular protrusions 215 may be
flexible or rigid. The tubular protrusions are configured to
provide a channel through which tubes 260 may pass, but which, in
the absence of tubes 260, inhibit movement of fluid therethrough.
For example, tubes 215 may inhibit fluid flow due to the ratio
between their length and lumen diameter, and/or may act as duckbill
valves. Therefore, sheet 214 typically provides a generally sealed
conduit between upstream support 210 and valve body 204.
[0470] The positioning of prosthetic valve assembly 202 at the
native valve typically results in leaflets 14 of the native valve
coapting around valve body 204, thereby providing sealing that
inhibits (e.g., prevents) perivalvular leakage.
[0471] The positioning of prosthetic valve assembly typically also
places sheet 214 in contact with the annulus and/or leaflets of the
native valve. In general, a prosthetic valve implanted at a native
valve encounters forces due to beating of the heart and/or the
resulting flow of blood. Small movements (e.g., oscillations)
resulting from these forces may inhibit tissue growth (e.g.,
fibrosis) that would otherwise facilitate sealing between the
prosthetic valve and the native valve. For some applications, such
movements are reduced (e.g., dampened) at sites at which the
contact between assembly 202 and the surrounding tissue is provided
by sheet 214, e.g., due to flexibility of the sheet. Thereby sheet
214 typically provides stabilized (e.g., more constant) contact
with tissue than would a less flexible structure in the same
position; this is hypothesized to improve tissue growth and thereby
sealing. Furthermore, sheet 214 itself may be configured to promote
tissue growth thereon, e.g., due to surface treatments and/or
impregnation, and/or structure, such as weave and/or porosity,
thereby further facilitating sealing.
[0472] Reference is made to FIGS. 9A-14B, which are schematic
illustrations of prosthetic valve assemblies, in accordance with
some applications of the invention. Each prosthetic valve assembly
shown in FIGS. 9A-14B comprises a valve body, an upstream support,
and a sheet, which are typically identical, mutatis mutandis, to
valve body 204, upstream support 210 and sheet 214 described
hereinabove, except for where noted.
[0473] FIGS. 9A-B show, prosthetic valve assembly 202 described
hereinabove, in a simplified (e.g., two-dimensional) schematic
manner that illustrates the arrangement of valve body 204, upstream
support 210 and sheet 214, in the compressed state (FIG. 9A) and
the expanded (e.g., implanted) state (FIG. 9B). FIGS. 9A-B are
included at least in part in order to facilitate interpretation of
the simplified schematic illustrations of the prosthetic valve
assemblies of FIGS. 10A-14B. FIG. 9A, like FIGS. 10A, 11A, 12A and
13A, shows the prosthetic valve assembly in the compressed state as
if it were contained in the delivery tool thereof (e.g., tool 230),
but for clarity does not show the delivery tool. Typically, sheet
214 is attached at least to inner perimeter 211 of upstream support
210, and to an upstream end 207 of frame 206 of valve body 204.
[0474] FIGS. 10A-B show a prosthetic valve assembly 302, which
comprises a valve body 304 comprising a first frame 306, an
upstream support 310 comprising a second frame 312, and a flexible
sheet 314. In the expanded state of support 310 (FIG. 10B), frame
312 defines an outer perimeter 313 and an inner perimeter 311 that
defines an opening through the support. During implantation,
support 310 is placed against the upstream surface of the native
valve, and valve body 304 is subsequently intracorporeally coupled
(e.g., directly coupled) to the support by being expanded within
the opening of the support, e.g., as described hereinabove with
reference to FIG. 1F, mutatis mutandis.
[0475] Sheet 314 is not attached to inner perimeter 311 of frame
312, but rather is circumferentially attached to frame 312 at a
radius that is greater than that of the inner perimeter. For
example, sheet 314 may be attached to frame 312 at outer perimeter
313. Sheet 314 is also not attached to an upstream end 307 of valve
body 304. Thereby a pocket region 316 is defined between sheet 314
and at least inner perimeter 311, in which sheet 314 is not
attached to frame 312 or frame 306.
[0476] In the compressed state (FIG. 10A), sheet 314 is disposed
alongside and outside at least part of frame 312 and at least part
of frame 306. Frame 312 is configured such that when the frame is
in the compressed state, inner perimeter 311 defines a downstream
end of the frame (e.g., of the cylindrical shape of the frame), and
outer perimeter 313 defines an upstream end. Therefore, when frame
312 expands, the upstream end of the frame expands radially outward
more than does the downstream end of the frame.
[0477] FIGS. 11A-B show a prosthetic valve assembly 342, which
comprises a valve body 344 comprising a first frame 346, an
upstream support 350 comprising a second frame 352, and a flexible
sheet 354. In the expanded state of support 350 (FIG. 11B), frame
352 defines an outer perimeter 353 and an inner perimeter 351 that
defines an opening through the support. During implantation,
support 350 is placed against the upstream surface of the native
valve, and valve body 344 is subsequently intracorporeally coupled
(e.g., directly coupled) to the support by being expanded within
the opening of the support, e.g., as described hereinabove with
reference to FIG. 1F, mutatis mutandis.
[0478] Sheet 354 is not attached to inner perimeter 351 of frame
352, but rather is circumferentially attached to frame 352 at a
radius that is greater than that of the inner perimeter. For
example, sheet 354 may be attached to frame 352 at outer perimeter
353. Sheet 354 is also not attached to an upstream end 347 of valve
body 344. Thereby a pocket region 356 is defined between sheet 354
and at least inner perimeter 351, in which sheet 354 is not
attached to frame 352 or frame 346.
[0479] Frame 352 is configured such that when the frame is in the
compressed state, the frame has a generally cylindrical shape that
defines a lumen therethrough, inner perimeter 351 defines an
upstream end of the frame (e.g., of the cylindrical shape of the
frame), and outer perimeter 353 defines a downstream end.
Therefore, when frame 352 expands, the downstream end of the frame
expands radially outward more than does the upstream end of the
frame. In the compressed state (FIG. 11A), sheet 354 is disposed
alongside and outside of at least part of frame 346, and through at
least part of the lumen defined by frame 352.
[0480] FIGS. 12A-B show a prosthetic valve assembly 382, which
comprises a valve body 384 comprising a first frame 386, an
upstream support 390 comprising a second frame 392, and a flexible
sheet 394. In the expanded state of support 390 (FIG. 12B), frame
392 defines an outer perimeter 393 and an inner perimeter 391 that
defines an opening through the support. Frame 392 is coupled to
frame 386 prior to implantation (e.g., assembly 382 is provided
with frame 392 coupled to frame 386). For some applications, frames
392 and 386 are integral, e.g., are defined by respective regions
of a single frame. During implantation, valve body 384 is advanced
between leaflets of the native valve, and support 390 is placed
against the upstream surface of the native valve (e.g., as
described with reference to FIGS. 8B-D, mutatis mutandis.
[0481] Sheet 394 is not attached to inner perimeter 391 of frame
392, but rather is circumferentially attached to frame 392 at a
radius that is greater than that of the inner perimeter. For
example, sheet 394 may be attached to frame 392 at outer perimeter
393. Sheet 394 is also not attached to an upstream end 387 of valve
body 384. Thereby a pocket region 396 is defined between sheet 394
and at least inner perimeter 391, in which sheet 394 is not
attached to frame 392 or frame 386.
[0482] Assembly 382 is configured such that, in the compressed
state thereof (FIG. 12A), frames 386 and 392 are generally
collinear, and form a generally continuous cylinder. Frame 392 is
configured such that in the compressed state, outer perimeter 393
defines an upstream end of the frame (and thereby of assembly 382).
Therefore, when frame 392 expands, the upstream end of the frame
expands radially outward more than does the downstream end of the
frame. In the compressed state, sheet 394 is disposed alongside and
outside of at least part of frame 386, and at least part of frame
392.
[0483] FIGS. 13A-B show a prosthetic valve assembly 402, which
comprises a valve body 404 comprising a first frame 406, an
upstream support 410 comprising a second frame 412, and a flexible
sheet 414. In the expanded state of support 410 (FIG. 13B), frame
412 defines an outer perimeter 413 and an inner perimeter 411 that
defines an opening through the support. Frame 412 is coupled to
frame 406 prior to implantation (e.g., assembly 402 is provided
with frame 412 coupled to frame 406). For some applications, frames
412 and 406 are integral, e.g., are defined by respective regions
of a single frame. During implantation, valve body 404 is advanced
between leaflets of the native valve, and support 410 is placed
against the upstream surface of the native valve (e.g., as
described with reference to FIGS. 8B-D, mutatis mutandis.
[0484] Sheet 414 is not attached to inner perimeter 411 of frame
412, but rather is circumferentially attached to frame 412 at a
radius that is greater than that of the inner perimeter. For
example, sheet 414 may be attached to frame 412 at outer perimeter
413.
[0485] Sheet 414 is also not attached to an upstream end 407 of
valve body 404. Thereby a pocket region 416 is defined between
sheet 414 and at least inner perimeter 411, in which sheet 414 is
not attached to frame 412 or frame 406.
[0486] Assembly 402 is configured such that, in the compressed
state thereof (FIG. 13A), frame 412 is disposed generally alongside
at least a portion of frame 406. Frame 412 is configured such that
in the compressed state, outer perimeter 413 defines a downstream
end of the frame. Therefore, when frame 412 expands, the downstream
end of the frame expands radially outward more than does the
upstream end of the frame. In the compressed state, sheet 414 is
disposed alongside and outside of at least part of frame 406.
[0487] FIGS. 14A-B show a prosthetic valve assembly 422 an expanded
state thereof, implanted at native valve 10, in accordance with
some applications of the invention. Assembly 422 comprises a valve
body 424 comprising a first frame 426, an upstream support 430
comprising a second frame 432, and a sheet 434.
[0488] Frame 426 of valve body 424 has an upstream end 427 and a
downstream end 429. In the expanded state, in the absence of
external forces, an outer perimeter 433 of second frame 432 of
upstream support 430 is disposed closer to downstream end 429 than
is an inner perimeter 431 of the second frame. For example,
upstream support 430 may define a frustum, the larger base of which
is disposed closer to downstream end 429 (and closer to a
ventricular end of an atrioventricular axis) than is the smaller
base of the frustum. For some applications, the assembly is thus
configured such that, when placed at the native valve, outer
perimeter 433 of the upstream support contacts the upstream surface
of the native valve (e.g., the valve annulus), and the inner
perimeter of the upstream support does not (FIG. 14A). For some
such applications, frame 432 may be flat annular in the absence of
external forces, and in the expanded state, sheet 434 retains the
second frame in the frustoconical shape by inhibiting expansion of
the second frame (e.g., expansion of at least outer perimeter 433
thereof). For some applications, frame 432 curves downward toward
the tissue that outer perimeter 433 contacts (configuration not
shown).
[0489] Sheet 434 is not attached to inner perimeter 431 of frame
432, but rather is circumferentially attached to frame 432 at a
radius that is greater than that of the inner perimeter. For
example, sheet 434 may be attached to frame 432 at outer perimeter
433. Sheet 434 is also not attached to upstream end 427 of valve
body 424. Thereby a pocket region 436 is defined between sheet 434
and at least inner perimeter 431, in which sheet 434 is not
attached to frame 432 or frame 426.
[0490] For some such applications, such a configuration provides a
spring functionality that allows valve body 424 to move along an
atrioventricular axis while outer perimeter 433 and/or portions of
sheet 434 remain in contact with tissue (FIG. 14B). For example,
assembly 422 may be implanted using techniques described with
reference to FIGS. 8A-H, mutatis mutandis, and the spring
functionality may allow movement of valve body 424 ventricularly
during tensioning of tethers 282 while maintaining contact between
outer perimeter 433 and the atrial surface. Similarly, such a
configuration may allow oscillation of valve body 424 along the
atrioventricular axis (e.g., caused by beating of the heart and the
resulting blood flow), while maintaining constant contact between
outer perimeter 433 and the tissue.
[0491] For some applications, a compressed state of assembly 422 is
as described for one or more of the prosthetic valve assemblies
described with reference to FIGS. 10A-13B, mutatis mutandis. For
example, for some applications frame 426 of body 424 is coupled to
frame 432 of support 430 prior to implantation (e.g., assembly 422
is provided with frame 426 coupled to frame 432), such as described
for assembly 382 and/or assembly 402, mutatis mutandis.
Alternatively, frame 426 is intracorporeally coupled to frame 432,
e.g., as described for assembly 302 and/or assembly 342, and/or
with reference to FIG. 1F, mutatis mutandis.
[0492] For some applications, assembly 422 is implanted as
described for one or more of the prosthetic valve assemblies
described with respect to FIGS. 10A-13B, mutatis mutandis.
[0493] Reference is again made to FIGS. 9A-B, 10A-B, and 11A-B. As
described hereinabove, in its compressed state, assembly 202
defines an articulation zone in which (a) at least part of sheet
214 is disposed, and (b) neither frame 206 of body 204 nor frame
212 of support 210 is disposed, and about which body 204 and
support 210 are articulatable with respect to each other. It is to
be noted that in their compressed states, assemblies 302 and 342
also define respective articulation zones 336, 376. For each
assembly, at least part of the respective sheet is disposed in the
articulation zone, neither the respective frame of the valve body
nor the respective frame of the support is disposed in the
articulation zone, and the respective valve body and support are
articulatable with respect to each other, about the articulation
zone.
[0494] Reference is again made to FIGS. 10A-B, 11A-B, 12A-B, 13A-B,
and 14A-B. As described hereinabove, assemblies 302, 342, 382, 402
and 422 each define a respective pocket region between the
respective sheet and at least the inner perimeter of the frame of
the upstream support. As also described hereinabove, (e.g., with
reference to assembly 202), placement of the flexible sheet of the
prosthetic valve assembly in contact with tissue provides
stabilized contact with the tissue, and thereby improves tissue
growth and sealing. Provision of a pocket region such as those
described hereinabove is hypothesized to further improve sealing
(e.g., by further facilitating tissue growth). For example, such
configurations (1) may provide a greater surface area of the
flexible sheet and/or a greater tissue-contact area of the sheet
(e.g., due to an angle of the sheet), and/or (2) may hold the
flexible sheet under less tension (e.g., compared to assembly 202),
such that the sheet is freer to move with movement of the valve
assembly and/or tissue, thereby dampening movements that may
otherwise inhibit tissue growth and/or sealing. This is illustrated
in FIGS. 14A-B, which show an example of the contact between
flexible sheet 434 and tissue (e.g., leaflets 14). For some
applications, the sheet is elastic, so as to further facilitate
maintenance of contact despite movement of the frames of the
prosthetic valve assembly with respect to the native valve.
[0495] As described hereinabove, the respective pocket region of
each assembly 302, 342, 382, 402 and 422 is defined by the manner
in which the sheet of the assembly is coupled to the frames of the
assembly. When the assembly is in the expanded state thereof, the
sheet is typically frustoconical and/or funnel-shaped. This shape
is defined by a lateral wall (i.e., the sheet itself), and first
and second apertures (at either end of the shape), the first
aperture being larger than the second aperture. A portion of the
sheet that defines the first aperture is circumferentially attached
to the frame of the upstream support at a radius that is greater
than a radius of the inner perimeter of the support. A portion of
the sheet that defines the second aperture is circumferentially
attached to the frame of the valve body at a longitudinal site that
is closer to a downstream end of the valve body than is the
longitudinal site at which the upstream support is coupled to the
valve body.
[0496] For some applications, the sheet extends radially past the
radius at which it is coupled to the upstream support. As described
hereinabove, for some applications the sheet is coupled to the
upstream support at an outer perimeter of the upstream support. For
some applications, the sheet extends radially past the outer
perimeter of the upstream support.
[0497] Reference is made to FIGS. 15A-C, which are schematic
illustrations of a tool 460 for facilitating application of force
between prosthetic valve assembly 202 and guide members 256 (e.g.,
tethers 282 thereof), in accordance with some applications of the
invention. For some applications, tool 460 serves as a
tension-detector tool. For some applications, tool 460
alternatively or additionally serves as a tension-applicator
tool.
[0498] The boxes on the right-hand side of FIGS. 15A-C shows
assembly 202 being implanted at native valve 10, as described
hereinabove. The box of FIG. 15A shows assembly 202 having been
deployed (e.g., delivered and expanded) at the native valve, e.g.,
as described with reference to FIG. 8D. The box of FIG. 15B shows
tethers 282 of guide members 256 having been tensioned with respect
to assembly 202, e.g., as described with reference to FIG. 8E. The
box of FIG. 15C shows tubular member 280 of each guide member 256
having been withdrawn proximally so as to (1) facilitate locking of
the respective locking member 262 to its respective tether 282,
e.g., as described with reference to FIG. 8F, and (2) decouple
pull-wire 284 from tether 282, e.g., as described with reference to
FIG. 8G.
[0499] The left-hand side of FIGS. 15A-C shows (1) a proximal end
of system 200 (e.g., a proximal end of delivery tool 230 thereof,
e.g., including a handle 231 thereof), including a proximal portion
of pull-wire 284, a proximal portion of tubular member 280, and a
proximal portion of reference-force tube 260, and (2) tool 460
coupled to the proximal portion of pull-wire 284 and the proximal
portion of reference-force tube 260. The left-hand side of FIGS.
15A-C shows one tool 460 being used with one pull-wire 284, tubular
member 280, tube 260 and tool 460 (and one handle 231). However it
is to be noted that tool 460 is typically used with each guide
member (e.g., each tether 282), either sequentially, or by
providing more than one tool 460 for use at generally the same
time.
[0500] Tool 460 comprises a pull-wire-coupling element 462,
configured to be coupled to the proximal portion of pull-wire 284
(e.g., to a grip 464 of the pull-wire), and a
reference-force-tube-coupling element 466, configured to be coupled
to the proximal portion of reference-force tube 260 (e.g., to a
grip 468 of the tubular member). Coupling elements 462 and 466 are
coupled to each other via an adjustment member 470 that facilitates
adjustment of a distance between the coupling elements. Adjustment
member 470 may comprise screw threads, a ratchet mechanism, or any
other suitable adjustment mechanism.
[0501] Pull-wire-coupling element 462 is coupled to the proximal
portion of pull-wire 284 (e.g., to a grip 464 of the pull-wire),
and reference-force-tube-coupling element 466 is coupled to the
proximal portion of reference-force tube 260 (e.g., to a grip 468
of the tubular member), typically subsequently to delivery of
prosthetic valve assembly 202 to the native valve (FIG. 15A). A
distance d7 exists between coupling elements 462 and 466.
[0502] Subsequently, adjustment member 470 is used (e.g., actuated)
so as to change (e.g., increase) the distance between coupling
elements 462 and 466 (FIG. 15B; distance d8).
[0503] This reduces the length of tether 282 that is disposed
distal to the distal end of reference-force tube 282, (and thereby
the length of the tether that is disposed between eyelet 222 and
anchor 48), thereby applying tension to the tether). Typically, a
length indicator 471 (e.g., a rule) is provided on tool 460 that
indicates the change in length that has been made. Further
typically, tool 460 comprises a force detector 472 that detects and
displays a force differential (e.g., a linear force differential)
between coupling elements 462 and 466, and thereby provides an
indication of the tensile state of tether 282.
[0504] When a desired tensile state of tether 282 has been achieved
(e.g., an absolute value and/or a value relative to other detected
forces, such as the tensile state of the other tether 282), the
tension is fixed, and pull-wire 284 is decoupled from tether 282
(FIG. 15C). As described with reference to FIG. 8F, this is
achieved by withdrawing tubular member 280 proximally with respect
to tether 282, pull-wire 284 and locking member 262. FIG. 15C shows
a proximal portion of tubular member 280 (e.g., a grip 474 thereof)
being withdrawn proximally with respect to (1) pull-wire 284 (and
therefore with respect to tether 282 to which the pull-wire is
coupled), and (2) reference-force tube 260 (and therefore with
respect to locking member 262 which the distal end of the
reference-force tube abuts). This is illustrated by a distance d10
between grips 468 and 474 in FIG. 15C, which is greater than a
distance d9 between grips 468 and 474 in FIG. 15B. This thereby
facilitates (1) locking of locking member 262 to tether 282, and
(2) subsequently (i.e., after further proximal withdrawal of the
tubular member), decoupling of pull-wire 284 from the tether.
[0505] For some applications, this is performed by one continuous
movement of tubular member 280. For some applications, visual
and/or tactile indicators allow the operating physician to lock
locking member 262 to tether 282 without decoupling pull-wire 284
from the tether. This may advantageously allow the physician to
further increase the tension on the tether (e.g., by using the
ratchet functionality described with reference to FIG. 8F) before
decoupling the pull-wire from the tether.
[0506] Although tool 460 is described hereinabove for facilitating
implantation of assembly 202, the tool may also be used, mutatis
mutandis, in combination with other systems described herein, such
as system 40 described hereinabove and/or assembly 552 described
hereinbelow (e.g., for tensioning tethers 582 thereof).
[0507] Reference is now made to FIG. 16, which is a schematic
illustration of a system 480 comprising a prosthetic valve assembly
482 and one or more springs 484 via which the prosthetic valve
assembly is elastically coupled to one or more tissue anchors 48,
in accordance with some applications of the invention. For
illustrative purposes, system 480 is shown as comprising system 200
(e.g., comprising prosthetic valve assembly 202), described
hereinabove, with the addition of springs 484. However it is to be
noted that the techniques described with reference to FIG. 16 may
alternatively or additionally be used to facilitate implantation of
other prosthetic valves and/or prosthetic valve assemblies
described herein, mutatis mutandis (e.g., springs 484 may be added
to other prosthetic valves and/or prosthetic valve assemblies
described herein).
[0508] Each spring 484 is disposed outside of valve body 204,
typically laterally outside the valve body, and further typically
between eyelet 222 and locking member 262 (e.g., coupling the
eyelet to the locking member). For example, and as shown, spring
484 may have a longitudinal axis that is generally parallel with
lumen 208 of the valve body. When reference-force tube 260 provides
the reference force to locking member 262 during tensioning of
guide member 256 (e.g., tether 282 thereof), the reference force is
transferred via spring 484. Typically spring 484 serves as a
compression spring, such that increasing tension on guide member
256 (e.g., the tether 282 thereof) compresses the spring.
[0509] For some applications, spring 484 provides an indication of
a state of the spring that is observable and recognizable using
imaging techniques (e.g., fluoroscopy). That is, spring 484 is
configured to change shape in response to a force applied to it, in
a manner that is observable and recognizable using fluoroscopy.
This functionality therefore provides intracorporeal measurement of
tension on tether 282 (in a manner that is itself observable
extracorporeally). It is hypothesized that for some applications,
this intracorporeal measurement advantageously detects the tension
with reduced interference (e.g., noise) that may be present in
extracorporeal measurement techniques. For example, for some
applications, extracorporeal measurement of the tension by
extracorporeally measuring tension on pull-wire 284 (e.g., tension
with respect to reference-force tube 280) may be inhibited by
interference by inherent elasticity of the pull-wire and other
elements of the system, and by friction between elements of the
system.
[0510] For some applications, the shape of spring 484 alone
provides the tension indication. For such applications, spring 484
may be coated with a radiopaque material such as tantalum. For some
applications, spring 484 has (e.g., comprises and/or is coupled to)
one or more radiopaque markers 486, and the juxtaposition of the
markers facilitates extracorporeal detection of the shape of the
spring. For example, when spring 484 serves as a compression
spring, a reduction of a distance d11 (compare d11 to d11') between
adjacent markers 486 indicates an increase in tension on tether
282.
[0511] For some applications, an intracorporeal reference (e.g., a
scale) 488 is provided, to facilitate identification of shape
change of spring 484 (e.g., to facilitate quantification of the
shape change by (1) comparing the position of markers 486 to
reference 488, and/or (2) comparing the juxtaposition of markers
486 to the juxtaposition of elements of the scale. For example, and
as shown in FIG. 16, scale 488 may itself also comprise a plurality
of radiopaque markers 490 disposed on valve body 204 (e.g., coupled
to frame 206) at known (e.g., regular) intervals, and distance d11
(observed using fluoroscopy) is compared to a distance d12 between
adjacent markers 490 (observed using fluoroscopy) in order to
determine the actual change in distance d11. That is, an observed
relative change between d11 and d12 is used to determine an actual
absolute change in d11.
[0512] For some applications, spring 484 also alters the
relationship between (a) changes in the length of tether 282
disposed between eyelet 222 and anchor 48 and (b) tension on the
tether. For example, for system 200 described hereinabove (i.e., in
the absence of spring 484), starting with slack on tether 282
between the eyelet and the anchor, as the length of the tether
between the eyelet and the anchor is reduced, tension on tether 282
may remain constant and low despite the reduction in the length of
the tether, until the tether encounters resistance provided by
tissue anchor 48, at which point tension increases relatively
quickly for every unit reduction in length. For system 480 (i.e.,
using spring 484), the relationship between (a) the length of
tether 282 disposed between the eyelet and the anchor, and (b) the
tension on the tether, is smoother (e.g., the transition between
before and after resistance from the anchor is encountered is
smoother). That is, spring 484 absorbs some of the applied tensile
force and in exchange provides additional length to the tether.
This is hypothesized to advantageously provide more flexibility to
the operating physician to adjust the length of tether 282 disposed
between the eyelet and the anchor, with reduced changes to tension
on the tether.
[0513] For some applications, spring 484 is configured so as to
provide a desired tension (e.g., a desired resistance) over a range
of lengths of tether 282 (e.g., over a range of compression states
of the spring). That is, the spring constant of the spring is
sufficiently low that a change in resistance is minimized per unit
length change. For example, the spring constant may be less than 50
g/mm.
[0514] For some applications, the desired tension is above 300 g
force and/or below 700 g force, e.g., above 400 g force, and/or
below 600 g force, such as between 400 g force and 600 g force,
e.g., about 500 g force. For example, a desired target tether
tension may be 500 g force, and spring 484 may be configured to
provide, over a range of compression states of the spring,
resistance that results in a tether tension that is within a margin
tension (e.g., within 200 g force, such as within 100 g force) of
the target force.
[0515] For some applications, spring 484 is configured to provide a
distinct indication, observable using fluoroscopy, when the spring
experiences a force that is within a margin force (i.e., a force
that corresponds to being within the margin tension). For example,
spring 484 may undergo (e.g., suddenly undergo) a more obvious
shape change when such a force is experienced.
[0516] For some applications, spring 484 is configured to act as a
constant-force spring or similar, so as to facilitate the behavior
described above. For some applications, spring 484 is pre-loaded
(e.g., pre-tensioned or pre-compressed).
[0517] Reference is made to FIG. 17, which is a schematic
illustration of a system 500 comprising a prosthetic valve assembly
502 and one or more springs 504 via which the prosthetic valve
assembly is elastically coupled to one or more tissue anchors 48,
in accordance with some applications of the invention. For
illustrative purposes, system 500 is shown as comprising system 200
(e.g., comprising prosthetic valve assembly 202), described
hereinabove, with the addition of springs 504. However it is to be
noted that the techniques described with reference to FIG. 17 may
alternatively or additionally be used to facilitate implantation of
other prosthetic valves and/or prosthetic valve assemblies
described herein, mutatis mutandis (e.g., springs 504 may be added
to other prosthetic valves and/or prosthetic valve assemblies
described herein).
[0518] Each spring 504 is disposed outside of valve body 204,
typically laterally outside the valve body, and further typically
is disposed functionally between locking member 262 and anchor 48
(e.g., between locking member 262 and eyelet 222, or between eyelet
222 and anchor 48. For some applications, and as shown, spring 504
is a cantilever spring, and may be defined by a protrusion of frame
206 that extends away (e.g., laterally away) from valve body 204.
That is, spring 504 may comprise an elastically-deformable
appendage. For some applications, the protrusion is shaped to
define a loop 506 that provides spring 504 with
constant-force-spring functionality.
[0519] Typically, spring 504 provides similar functionality to
spring 484, described hereinabove, mutatis mutandis. For example,
for some applications, spring 504 provides an indication of a state
of the spring that is observable and recognizable using
fluoroscopy. That is, spring 504 is configured to change shape in
response to a force applied to it, in a manner that is detectable
and recognizable using fluoroscopy. For some applications, spring
504 also alters the relationship between (a) the length of tether
282 disposed between eyelet 222 and anchor 48 and (b) tension on
the tether, e.g., as described hereinabove with reference to spring
484, mutatis mutandis.
[0520] Reference is made to FIGS. 18A-B, which are schematic
illustrations of springs coupled to tether 282 so as to elastically
couple tissue anchor 48 (e.g., a tissue-engaging element 49
thereof) to prosthetic valve assembly 202 (e.g., to valve body 204
thereof), in accordance with some applications of the invention.
FIG. 18A shows a spring 520 disposed partway along tether 282. FIG.
18B shows a spring 530, one end of which is coupled to anchor 48
(e.g., to an anchor head 47 thereof) and the other end of which is
coupled to tether 282. Springs 520 and 530 are typically tension
springs. For some applications, spring 530 is rigidly coupled to
anchor head 47.
[0521] For illustrative purposes, springs 520 and 530 are shown
being used with system 200 (e.g., with prosthetic valve assembly
202), described hereinabove. However it is to be noted that the
techniques described with reference to FIGS. 18A-B may
alternatively or additionally be used to facilitate implantation of
other prosthetic valves and/or prosthetic valve assemblies
described herein, mutatis mutandis.
[0522] Typically, springs 520 and 530 provide similar functionality
to springs 484 and 504, described hereinabove, mutatis mutandis.
For example, for some applications, springs 520 and 530 provide an
indication of a state of the spring that is observable and
recognizable using fluoroscopy. That is, the springs are configured
to change shape in response to a force applied to them, in a manner
that is detectable and recognizable using fluoroscopy. For some
applications, springs 520 and 530 also alter the relationship
between (a) the length of tether 282 disposed between eyelet 222
and anchor 48 and (b) tension on the tether, e.g., as described
hereinabove with reference to springs 484 and 504, mutatis
mutandis.
[0523] Reference is again made to FIGS. 16, and 18A-B. Springs 484,
520 and 530 are shown as helical springs. However it is to be noted
that each of these springs may have a shapes other than a helix.
For example, each of these springs may have a zigzag shape. For
some applications, the use of a spring that defines a repeating
(e.g., oscillating) pattern such as a helix or a zigzag facilitates
fluoroscopic identification of the state of the spring. For
example, whereas a linear elastically-stretchable member (e.g., a
strip of elastic rubber) remains linear when stretched, the shape
of a helical or zigzag spring changes as force increases.
[0524] Reference is made to FIGS. 19A-B, which are schematic
illustrations of a system 700 for facilitating delivery of a
prosthetic valve body 702, in accordance with some applications of
the invention. System 700 comprises a delivery tool 704 that
comprises a distal housing 706, configured to house valve body 702
in a compressed state thereof, a proximal portion 708, and a
flexible longitudinal portion 710 (e.g., a catheter) therebetween.
Proximal portion 708 typically comprises a handle 712. Housing 706
is configured to be transluminally advanced to the heart of the
subject (e.g., as described herein, mutatis mutandis, while
proximal portion 708 remains outside the body of the subject.
Proximal portion 708 (e.g., handle 712 thereof) comprises a force
detector 716 that detects a force between (a) the proximal portion,
and (b) housing 706 and/or valve body 702 coupled thereto.
Typically, force detector 716 detects tension. That is, the force
detector detects resistance of valve body 702 to a
proximally-directed force applied by tool 704 (e.g., when tool 704
is moved proximally).
[0525] Housing 706 is advanced through native valve 10 and into
ventricle 8, and valve body 702 is partly advanced out of the
housing, and automatically expands toward an expanded state (FIG.
19A). Valve body 702 is coupled to a plurality of tissue-engaging
elements (e.g., tissue-engaging legs) 714 that protrude radially
out from the valve body when exposed from housing 706.
Tissue-engaging elements 714 are configured to engage leaflets 14
of the native valve, thereby facilitating anchoring of the valve
body.
[0526] Typically system 700 is used for implantation of valve body
702 at a native valve at which a prosthetic valve support (e.g., an
upstream support) has already been delivered, and to which the
valve body is intracorporeally coupled (e.g., as described
elsewhere herein). For example, and as shown in FIGS. 19A-B, system
700 may be used to implant valve body at native valve 10 after
implantation of support 42 at the native valve. As described with
reference to FIGS. 1A-D, support 42 is secured against the upstream
surface of native valve 10 by being anchored, via tethers (e.g.,
longitudinal members 102), to ventricular muscle tissue. (The
tethers are not visible in FIGS. 19A-B.)
[0527] Pulling housing 706 and valve body 702 proximally (i.e.,
atrially) while tissue-engaging elements 714 are protruding pushes
the tissue-engaging elements against leaflets 14, reducing a height
of a gap between the tissue-engaging elements and support 42, and
sandwiching the leaflets against the support (FIG. 19B). Resistance
to proximal movement of valve body 702 (e.g., due to support 42 and
leaflets 14) is detected and displayed by force detector 716. The
operating physician is thereby able to couple valve body 702 to
support 42 (e.g., by fully deploying the valve body within the
opening defined by the support) while a desired degree of tension
is observed. The coupling of the valve body to the support fixes
the degree of tension, such that leaflets 14 remain sandwiched, and
the valve body remains secured to the native valve.
[0528] For some applications, alternatively or additionally to
using extracorporeal force detector 716, the force encountered by
tissue-engaging elements 714 is observed using fluoroscopy (e.g.,
by observing a shape and/or position of the tissue-engaging
elements). For such applications, the tissue-engaging elements are
typically configured to facilitate such observation, as described
herein for various springs. For some applications, elements 714 are
configured (e.g., shaped) to define a loop, e.g., as described
hereinabove for springs 504, mutatis mutandis.
[0529] For some applications, valve body 702 is coupled via tethers
to tissue anchors that are anchored to ventricular muscle tissue,
as described elsewhere herein. For some such applications, a spring
couples the valve body to each tissue anchor (e.g., as described
with reference to FIGS. 16-18B, mutatis mutandis). For some
applications in which a spring couples the valve body to each
tissue anchor, reducing the height of the gap automatically (and
typically immediately) alters a force on the spring (e.g., when the
valve body is locked to the tether before reducing the height of
the gap). For some applications in which a spring couples the valve
body to each tissue anchor, reducing the height of the gap does not
necessarily alter the force on the spring (e.g., when the valve
body is slidably couplable to the tether until after the height is
reduced, and is subsequently locked to the tether. For example,
tool 230 and/or tool 460 may be used, mutatis mutandis, to measure
and control tension and length of the tether until the valve body
is locked to the tether.
[0530] It is to be noted that the above technique may be used for
prosthetic valve assemblies in which the valve body is pre-coupled
to the upstream support, mutatis mutandis. For such applications,
the proximal pulling force is not a sandwiching force, but rather
is a testing force, typically used in combination with another
testing force, e.g., as described hereinbelow, e.g., with reference
to FIG. 20.
[0531] Reference is made to FIG. 20, which is a schematic
illustration showing examples in which force measurements described
herein may be combined to facilitate implantation of a prosthetic
valve, in accordance with some applications of the invention. Each
apparatus and technique described herein for measuring force (e.g.,
tension) is described in a particular context (e.g., with reference
to a particular prosthetic valve assembly, prosthetic valve body,
and/or support) for the purpose of clarity. It is to be understood
that the apparatus and techniques described in one context may be
used to measure force in another context (e.g., to facilitate
controlled implantation of a different prosthetic valve assembly,
prosthetic valve body, and/or support), and may be combined with
one or more of the other apparatus and/or techniques.
[0532] FIG. 20 shows examples of combinations of apparatus and
techniques described herein, which include:
[0533] (1) Extracorporeal detection of tension on tethers (box
722). This is described, for example, with reference to force
detector 472 of tool 460 of FIGS. 15A-C.
[0534] (2) Extracorporeal detection of atrially-directed force of
valve-mounted tissue-engaging elements against tissue (e.g.,
leaflets or annulus) of the native valve (box 742). This is
described, for example, with reference to FIGS. 19A-B.
[0535] (3) Extracorporeal detection of sandwiching force (box 720).
That is, extracorporeal detection of the force of tissue-engaging
elements coupled to the valve body against the native valve tissue
and/or the upstream support. This is described, for example, (a)
with reference to FIGS. 19A-B, and (b) with reference to force
detector 472 of tool 460 (FIGS. 15A-C) being used to augment the
apparatus and facilitate the techniques described with reference to
FIGS. 21A-B.
[0536] (4) Intracorporeal detection (observed using imaging) of
tension on tethers (724). This is described, for example, with
reference to the springs described with reference to FIGS. 16, 17,
and 18A-B.
[0537] (5) Intracorporeal detection (observed using imaging) of
atrially-directed force of valve-mounted tissue-engaging elements
against tissue (e.g., leaflets or annulus) of the native valve (box
744). This is described, for example, with reference to FIGS.
19A-B.
[0538] (6) Intracorporeal detection (observed using imaging) of
sandwiching force (box 726). This is described, for example, with
reference to one or more of the springs described with reference to
FIGS. 16, 17, and 18A-B being used to augment the apparatus and
facilitate the techniques described with reference to FIGS.
21A-B.
[0539] (7) Intracorporeal detection (observed using imaging) of
ventricularly-directed force of the upstream support against the
native annulus (box 728). For some applications, this is achieved
by using imaging (e.g., fluoroscopy) to extracorporeally observe
intracorporeal changes in the shape of the upstream support (e.g.,
changes described with reference to FIGS. 8D-E, 14A-B, and/or
15A-B), in a similar manner to that described for extracorporeally
observing changes in the shape of springs (e.g., described with
reference to FIGS. 16, 17, and 18A-B), mutatis mutandis.
[0540] It is hypothesized that combining two or more of the
force-measurement techniques described herein may provide
synergistic benefits when implanting an implant (e.g., a prosthetic
valve assembly, prosthetic valve body, and/or prosthetic valve
support), so as to facilitate controlled implantation (box 730).
The ability to control various forces that secure the implant
allows, inter alia, the forces to be spread as desired by the
operating physician. For example, it may be desirable: [0541] that
tension is equally (or otherwise) distributed between the tethers,
[0542] that tension on a given tether is optimized (discussed
hereinbelow), [0543] that, during operation of the valve,
resistance to a force that pushes the valve body in an atrial
direction (e.g., during ventricular systole) is optimally balanced
between the various anchoring elements, such as between (a) tissue
anchors 48 and tethers coupled thereto and (b) other
tissue-engaging elements (e.g., tissue-engaging elements 714 (FIGS.
19A-B) or tissue-engaging elements 580 (FIGS. 21A-B), thereby
balancing the anchoring forces between different tissue sites,
and/or [0544] that sandwiching forces are greater than, equal to,
or less than the tensile force provided by the tethers.
[0545] It is to be noted that the example combinations provided
hereinabove are intended to be illustrative, and not limiting.
[0546] As described hereinabove, it may be desirable to that
tension on a given tether is optimized. For example, it may be
desirable that tension on the given tether to be maximized within a
tension range that is known to be supported by (1) the tissue
anchor to which the tether is coupled, and (2) the tissue to which
the tissue anchor is anchored. For some applications, subsequently
to anchoring the tissue anchor, the operating physician applies a
testing pulling force to the tissue anchor. The testing pulling
force is used to confirm that the anchored tissue anchor is capable
of supporting an overload tension that is greater than an expected
tension that it is expected that the anchor will encounter during
operation. The expected tension may be determined at least in part
based on possible ventricular blood pressure and the
cross-sectional area of the lumen of the valve body.
[0547] For some applications, the testing pulling force is applied
(e.g., via the tether or via the anchor manipulator), and movement
of the tissue anchor is observed using imaging, e.g., as described
with reference to FIGS. 1A-B). For some applications, the testing
pulling force is applied while measuring tension using an
extracorporeal force detector such as detector 472 (FIGS. 15A-C),
mutatis mutandis.
[0548] For some applications, the testing pulling force is applied
by applying tension to the tether, and the tension is measured
using intracorporeal springs and fluoroscopy, as described
hereinabove, mutatis mutandis. It is to be noted that, for such
applications, the same technique is used (1) to confirm that the
anchored tissue anchor is capable of supporting the overload
tension, and (2) to facilitate the application of the tension
(e.g., the anchoring tension) that will be fixed when the locking
member is locked to the tether.
[0549] As described hereinabove, it may be desirable that, during
operation of the valve, resistance to a force that pushes the valve
body in an atrial direction (e.g., during ventricular systole) is
optimally balanced between the various anchoring elements. For some
applications, the following technique is used:
[0550] (1) Anchor at least one tissue anchor coupled to a
respective at least one tether (e.g., within guide members).
[0551] (2) Advance a valve body that comprises at least one
tissue-engaging element (e.g., a tissue-engaging leg) over at least
part of the tether (e.g., by advancing over a guide member), such
that a length of the tether is disposed between the valve body and
the tissue anchor. Examples of such tissue-engaging elements are
described with reference to FIGS. 19A-B and 21A-B. The valve body
may or may not be pre-coupled to an upstream support.
[0552] (3) Apply a first tension to the tether (measured
intracorporeally or extracorporeally).
[0553] (4) Apply proximal pulling force to the valve body such that
the tissue-engaging element applies force against tissue of the
native valve, such as leaflets and/or annulus. This pulling
typically automatically increases the tension on the tether.
[0554] (5) While applying the proximal pulling force,
intracorporeally and/or extracorporeally measure (a) force of
tissue-engaging element against tissue, and (b) tension on the
tether (e.g., the change in tension on the tether caused by the
proximal pulling.
[0555] (6) At least in part based on measurements (a) and (b) of
step 5, adjust the length of the tether disposed between the valve
body and the tissue anchor, and/or lock the valve body to the
tether (i.e., fix the length of the tether disposed between the
valve body and the tissue anchor).
[0556] It is hypothesized that the above technique provides a
prediction of the force distribution between the various anchoring
elements that will exist during operation of the prosthetic valve
assembly (e.g., during the lifetime thereof). For example, the
technique provides a prediction of force distribution between the
ventricular anchors and the valve-mounted tissue-engaging elements
if/when atrially-directed force increases (e.g., as will be
encountered during ventricular systole and/or increases in systemic
blood pressure). Based on this indication, the technique
facilitates adjustment of this distribution, via adjustment of the
length of tethers disposed between the valve body and the tissue
anchors.
[0557] Reference is made to FIGS. 21A-B, which are schematic
illustrations of a prosthetic valve assembly 552, in accordance
with some applications of the invention. Prosthetic valve assembly
552 comprises (1) a prosthetic valve body 554, which comprises a
first frame 556 (e.g., a wire frame), and is shaped to define a
lumen therethrough, (2) an annular upstream support 560, which
comprises a second frame 562 (e.g., a wire frame), is shaped to
define an opening through the upstream support, and is configured
to be placed against an upstream surface (e.g., an atrial surface)
of native valve 10 (e.g., of an annulus thereof), and (3) a
flexible sheet 564 that couples the first frame to the second
frame. FIG. 21A shows assembly 552 in an expanded state thereof
(e.g., in the absence of external forces, such as if the assembly
were resting on a table surface). In the expanded state of assembly
552 (and thereby of body 554), frame 556 of body 554 is generally
cylindrical, and has a diameter d13. In the expanded state of
assembly 552 (and thereby of upstream support 560), frame 562 of
support 560 is typically generally annular, and has an outer
perimeter 563 that has a diameter d14, which is greater than
diameter d13.
[0558] Assembly 552 comprises one or more tissue-engaging elements
580 (e.g., legs) that protrude radially outward from valve body 554
so as to define a diameter d15, which is greater than diameter d13.
Typically, and as shown in FIGS. 21A-B, frame 556 of body 554 is
shaped to define tissue-engaging elements 580. Assembly 552 further
comprises one or more tensioning elements (e.g., contraction wires)
such as one or more tethers 582, a first portion (e.g., a distal
end) of each tether being coupled to valve body 554, and a second
portion of each tether being coupled (e.g., slidably coupled) to a
portion of assembly 552 that is configured to be placed upstream of
valve body 554. For example, and as shown, the second portion of
each tether 582 may be slidably coupled to an upstream region of
sheet 564. Alternatively or additionally, the second portion of
each tether 582 may be slidably coupled to frame 562 of support
560. For some applications, this is facilitated by frame 562 being
shaped to define one or more respective protrusions that protrude
radially inward from the annular shape of the frame, to the site at
which each tether 582 is shown in FIG. 21A passing through the
sheet.
[0559] For some applications, except for (1) the presence of
tissue-engaging elements 580 and tethers 582, and (2) the absence
of eyelets 222, assembly 552 is identical to (e.g., comprises the
same components as, and/or has identical functionality to) assembly
202, described hereinabove. Identically-named components of system
202 and system 552 are typically identical in structure and/or
function.
[0560] For some applications, assembly 202 comprises
tissue-engaging elements 580 and/or tethers 582. For some
applications, assembly 552 comprises eyelets 222 and/or locking
members 262 for sliding over and locking to guide members.
[0561] Both support 560 of assembly 552 and support 210 of assembly
202 may be flat annular (e.g., as shown for support 210) or
frustoconical (as shown for support 560).
[0562] FIG. 21B shows assembly 552 being implanted. Following
transluminal delivery to native heart valve 10, valve body 554 is
typically deployed first (i.e., before support 560), as shown in
state A of FIG. 21B. For some applications, valve body is deployed
sufficiently far into the ventricle that tissue-engaging elements
580 can expand freely without interfering with leaflets 14 of the
native valve, and valve assembly is subsequently moved atrially
into the position shown in state A of FIG. 21B.
[0563] Subsequently, upstream support 560 is deployed, e.g., by a
delivery housing 584 thereof being retracted (state B of FIG. 21B).
Support 560 becomes placed against the upstream (e.g., atrial)
surface of native valve 10, such as against the annulus of the
valve and/or against the upstream surface of native leaflets 14.
Typically, immediately subsequently to deployment of body 554 and
support 560, assembly 552 has a total height d16 from a proximal
end of support 560 to a distal end of body 554 (e.g., a height
along an atrioventricular axis), and a distance d17 (e.g., a gap)
measured along the height exists between a distal end of frame 562
and a proximal-most part of frame 554 (e.g., tissue-engaging
elements 580 defined by the frame).
[0564] Subsequently, tethers 582 are tensioned so as to draw
support 560 and body 554 closer to each other, thereby reducing the
total height of assembly 552 to height d18, and reducing the
distance between the distal end of frame 562 and the proximal-most
part of frame 554 to a distance d19 (state C of FIG. 21B). This
moves body 554 and tissue-engaging elements 580 closer to leaflets
14, thereby sandwiching the leaflets between the tissue-engaging
elements and support 560, and thereby anchoring assembly 552 at the
native valve. Sheet 564 maintains fluid communication (e.g., sealed
fluid communication) through assembly 252, while also allowing the
described contraction of the assembly. Typically, this
characteristic is due to sheet 564 having tensile strength, but not
compressive strength, and therefore rumpling when tethers 582 are
tensioned.
[0565] Tensioning of tethers 582 may be accomplished by any
suitable technique. For some applications, the tensioning is
performed using control rods 86 and locking members 110, e.g., as
described with reference to FIGS. 1C-D, mutatis mutandis. For some
applications, the tensioning is performed using reference-force
tubes and locking members, e.g., as described with reference to
FIGS. 7B-8H, mutatis mutandis. For some applications, support 560
comprises a ratchet mechanism that facilitates the tensioning by
allowing only one-way movement of tether 582 through the support.
For some applications, assembly 552 comprises a spool mechanism for
each tether, and tensioning is performed by rotating the spool
mechanism.
[0566] For some applications, assembly 552 has a compressed state
(e.g., for transluminal delivery) in which the assembly defines an
articulation zone between frames 556 and 562, e.g., as described
hereinabove for assembly 202, mutatis mutandis.
[0567] For some application, one or more of the techniques
described hereinabove may be used to (1) control applied to tethers
582, and/or (2) facilitate intracorporeal measurement of tension on
the tethers (and optionally fluoroscopic detection of that
measurement). For example, assembly 552 may comprise a tension
spring midway along each tether 582, and/or may comprise a
compression spring at the coupling point of support 560 and the
tether (e.g., between the support and a locking member 262
configured to lock a respective tether to the support).
Alternatively or additionally, for applications in which the
tensioning is performed using reference-force tubes and locking
members (e.g., as described with reference to FIGS. 7B-8H), tool
460 may be used, mutatis mutandis, to extracorporeally detect the
tension applied to tethers 582.
[0568] Reference is made to FIGS. 22A-B, which are schematic
illustrations of a prosthetic valve assembly 602, comprising a
prosthetic valve 603 having a tubular valve body 604 that comprises
an upstream portion 606, a downstream portion 608, and an elastic
portion 610 disposed between the upstream portion and the
downstream portion, in accordance with some applications of the
invention. Prosthetic valve 603 (e.g., valve body 604 thereof) is
shaped to define a continuous lumen through portions 606, 610, and
608. Prosthetic valve 603 is configured to be implanted at native
valve 10 such that upstream portion 606 is disposed in atrium 6 of
the heart of the subject, and such that downstream portion 608 is
disposed in ventricle 8 of the heart of the subject. For example,
prosthetic valve 603 may be coupled to a prosthetic valve support
612 that has been previously placed against (e.g., coupled to) to
the native valve, and that defines an opening. Support 612 may
comprise (1) a support described elsewhere herein (e.g., support 42
described with reference to FIGS. 1A-F and 19A-B, support 310
described with reference to FIGS. 10A-B, and/or support 350,
described with reference to FIGS. 11A-B, and/or (2) a support
described in U.S. Provisional Patent application 61/756,034 to
HaCohen et al., from which the present application claims priority,
and which is incorporated herein by reference.
[0569] For some applications, and as shown in FIG. 22B, prosthetic
valve support 612 comprises one or more tissue-engaging elements
618, an annular upstream support portion 620, and a flexible
stabilizing member 622, such as a stabilizing band, coupled to the
tissue-engaging elements, and configured to form a ring that is
shaped to define an opening therethrough. Tissue-engaging elements
618 may comprise, as shown in FIGS. 22A-B, clips configured to be
coupled to leaflets 14 of the native valve.
[0570] Tubular valve body 604 typically comprises a frame 614, such
as a stent-like wire frame. As shown in FIG. 22A, prosthetic valve
603 typically further comprises a covering 616, disposed over
(e.g., covering) an inner surface of frame 614, thereby providing a
sealed lumen from an upstream end to a downstream end of the
tubular valve body. Typically, an excess of covering 616 is
provided in the vicinity of elastic portion 610, so as to
facilitate elastic stretching of the elastic portion.
[0571] Typically, prosthetic valve 603 comprises an expandable
prosthetic valve, and is deployed such that it (1) expands within
the opening defined by upstream support portion 620 and/or the
opening defined by stabilizing member 622, (2) applies a
radially-expansive force against the upstream support portion
and/or the stabilizing member, and (3) thereby becomes coupled
thereto. Typically, and as shown in FIG. 22B, downstream portion
608 is expanded and coupled to stabilizing member 622 before
upstream portion 606 is expanded and coupled to upstream support
portion 620. While downstream portion 608 is coupled to member 622,
and before upstream portion 606 is coupled to portion 620, elastic
portion 610 may be stretched and compressed e.g., such as by moving
upstream portion 606 further upstream and downstream. Such
stretching and compressing changes a length of prosthetic valve
603, and for some applications, facilitates the coupling of a
pre-determined portion of the prosthetic valve (e.g., of upstream
portion 606) to upstream support portion 620, irrespective, to some
degree, of (a) a distance between tissue-engaging elements 618 and
upstream support portion 620, and/or (b) a dimension of native
valve 10 (e.g., a length of leaflets 14). For some applications,
such stretching and compressing adjusts a degree of tension of
elastic portion 610, and may alternatively or additionally
facilitate "tightening" of leaflets 14 against the implanted
apparatus, such as drawing of the leaflets toward upstream support
portion 620.
[0572] For some applications, prosthetic valve 603 may be used in
combination with other apparatus and techniques described herein.
For example, valve body 604 may be substituted for another valve
body described herein, mutatis mutandis, including valve bodies
that are described herein as being intracorporeally coupled to an
upstream support, and valve bodies that are described herein as
being provided pre-coupled to an upstream support (either directly,
or via a flexible sheet).
[0573] Reference is made to FIGS. 23-24, which are schematic
illustrations of respective systems for facilitating anchoring of a
tissue anchor in the heart of a subject, in accordance with some
applications of the invention. Each system comprises a delivery
tool that comprises (1) a steerable catheter configured to be
transluminally advanced to the heart of the subject (e.g., via
sheath 46), and (2) an obstructing element disposed at a
longitudinal site of the catheter, and configured to extend
laterally (e.g., radially) outward from the catheter so as to
inhibit movement of at least the longitudinal site of the catheter
through the heart valve by abutting tissue of the heart valve.
[0574] FIG. 23 shows a system 640, comprising a delivery tool 642
that comprises a catheter 644 and an obstructing element 646.
Obstructing element 646 is typically collapsible for transluminal
delivery (e.g., via sheath 46), and expandable in atrium 6 of the
heart. For some applications, element 646 is configured to expand
automatically upon becoming exposed from the distal end of sheath
46. Obstructing element 646 is disposed at a longitudinal site 648
of catheter 644, and is dimensioned, when in the expanded state
thereof, to not pass through native valve 10 (i.e., between
leaflets 14 of the native valve). When a distal end 645 of the
catheter is extended through native valve 10, obstructing element
646 abuts the atrial surface of the native valve (e.g., one or more
leaflets, or the annulus), and thereby inhibits movement of at
least longitudinal site 648 of the catheter from passing through
the valve. Therefore a known length d20 of catheter 644 (i.e., the
length between longitudinal site 648 and distal end 645) is
disposed downstream of the atrial surface of valve 10. Distal end
645 is thereby placeable against ventricular tissue at ventricular
sites that are disposed at a distance from the atrial surface
(e.g., from a portion of the atrial surface that element 646 abuts)
that is generally equal to d20. A distal portion 652 of catheter
644, disposed distal to longitudinal site 648, is typically
steerable, so as to facilitate placement of distal end 645 against
many (e.g., any) ventricular site that is disposed at that distance
from the atrial surface.
[0575] A tissue anchor 48 is advanced through catheter 644 using an
anchor manipulator 650, and anchored to tissue at the ventricular
site at which distal end 645 is disposed. Typically, little or none
of anchor 48 or manipulator 650 becomes exposed from distal end 645
during anchoring.
[0576] FIG. 24 shows a system 660, comprising a delivery tool 662
that comprises a catheter 664 and an obstructing element 666.
Obstructing element 666 is typically collapsible for transluminal
delivery (e.g., via sheath 46), and expandable in atrium 6 of the
heart, and may be identical to obstructing element 646, described
hereinabove. For some applications, element 666 is configured to
expand automatically upon becoming exposed from the distal end of
sheath 46. Obstructing element 666 is disposed at a longitudinal
site 668 of catheter 664, and is dimensioned, when in the expanded
state thereof, to not pass through native valve 10 (i.e., between
leaflets 14 of the native valve). When a distal end 665 of the
catheter is extended through native valve 10, obstructing element
666 abuts the atrial surface of the native valve (e.g., one or more
leaflets, or the annulus), and thereby inhibits movement of at
least longitudinal site 668 of the catheter from passing through
the valve. Therefore a known length d21 of catheter 664 (i.e., the
length between longitudinal site 668 and distal end 665) is
disposed downstream of the atrial surface of valve 10.
[0577] Length d21 of system 660 is typically shorter than length
d20 of system 640, and in contrast to system 640, for system 660,
catheter 664 is not configured for distal end 665 to be placed
against ventricular tissue. Rather, an anchor manipulator 670
advances tissue anchor 48 through catheter 664, out of the distal
end 665, and toward a ventricular site at which it anchors the
tissue anchor. Typically, anchor manipulator 670 is slidably
coupled to catheter 664 such that a distal end of the anchor
manipulator is slidable distally no more than a pre-determined
distance d22 from longitudinal site 668 (and thereby no more than a
pre-determined distance from distal end 665 of catheter 664).
Anchor manipulator 670 is thereby used to anchor anchor 48 at a
ventricular site that is disposed at a distance from the atrial
surface (e.g., from a portion of the atrial surface that element
666 abuts) that is generally equal to d22. Typically, anchor
manipulator 670 (or at least a distal portion 672 thereof that is
exposable from distal end 665 of catheter 664) is steerable
independently of catheter 664.
[0578] It is to be noted that, for systems 640 and 660, the
distance from the atrial surface at which anchor 48 is anchored is
generally equal, but not necessarily exactly equal, to d20 or d22.
For example, anchor 48 may be anchored at a site that is closer to
another portion of the atrial surface than to the portion of the
atrial surface that the obstructing element abuts. Alternatively or
additionally, curvature of the catheter and/or the anchor
manipulator may result in a direct distance between the atrial
surface and the tissue anchor being smaller than d20 or d22.
[0579] Typically, anchor 48 is coupled to a tether, guide member,
and/or other longitudinal member (e.g., as described hereinabove
with reference to other systems). When the anchor driver is
decoupled from the anchor and withdrawn proximally, the tether
extends proximally from the anchor (e.g., out of the body of the
subject) so that an implant, such as a prosthetic valve, prosthetic
valve support, and/or a prosthetic valve assembly (e.g., those
described hereinabove) may be advanced therealong and/or locked
thereto, e.g., as described hereinabove for other systems, mutatis
mutandis. Because the distance between the tissue anchor and the
atrial surface is known, for some applications the tether coupled
to the tissue anchor may comprise fewer locking sites for locking
to the implant, a relatively shorter locking site, and/or only one
locking site. It is hypothesized that this may provide the
possibility of using simpler, smaller and/or more effective
mechanisms to lock the implant to the tether.
[0580] Reference is again made to FIGS. 7A-C, 8A-H, 9A-B, 15A-C,
16, 17, 18A-B, and 21A-B. The flexible sheets described hereinabove
typically have tensile strength but very low compressive strength
along the longitudinal axis of assembly 202. Due to this
characteristic, inter alia, implant-control rod 246 is coupled (via
mount 248) to assembly 202 by being coupled to valve body 204, such
that when the valve body is pushed distally, the valve body pulls
upstream support 210 via sheet 214. (It is hypothesized that it
would be less effective for the implant-control rod to be coupled
to the support, because in such a case sheet 214 may rumple and the
support may move toward the valve body, possibly reducing
articulation at the articulation zone. Nevertheless, for
applications in which such reduced articulation is in any case
sufficient, the implant-control rod may be coupled to the support)
This characteristic of the flexible sheet also facilitates the
height-adjustment of assembly 552 and its sandwiching of the native
leaflets by tensioning tethers 582.
[0581] Although each of the prosthetic valve assemblies is shown
implanted in a generally symmetrical state, it is to be noted that
for some applications this characteristic of the sheet facilitates
asymmetrical implantation. For example, the assembly may better
conform to the native anatomy, and/or one tether of assembly 552
may be tensioned more than another so as to alter the anchoring,
sealing, and/or flow characteristics of the assembly, e.g., in
response to the native anatomy.
[0582] For some applications it may be advantageous for the valve
body to be disposed at a particular rotational orientation within
ventricle 8, and for the upstream support to be disposed at a
particular rotational orientation within atrium 6. For example, for
prosthetic valve assemblies such as assembly 202 that are tethered
to ventricular anchors, it may be advantageous for each eyelet to
be aligned with a respective anchor, and for the point at which
each guide members passes through the upstream support to be
aligned with a respective commissure. Alternatively or
additionally, the upstream support may be geometrically asymmetric,
and a particular rotational orientation with respect to atrial
tissue may be advantageous. (Examples of such upstream supports are
described in PCT patent application publication WO/2013/021374 to
Gross et. al, which is incorporated herein by reference.)
Alternatively or additionally, the upstream support may be
asymmetric with respect to rigidity (i.e., some regions of the
support may be more rigid than others). Alternatively or
additionally, it may be advantageous to place the holes in sheet
214 through which tubes 260 pass in a particular rotational
orientation with respect to the native valve.
[0583] For some applications, the sheet facilitates implantation of
the upstream support in a different rotational position to its
valve body, e.g., by twisting. For example, the upstream support
may be implanted at more than 5 degrees (e.g., more than 10
degrees, such as more than 20 degrees) rotational offset with
respect to the valve body.
[0584] Reference is again made to FIGS. 7A-14B, 16-18B, and 21A-B.
For some applications the first frame of the valve body is coupled
to the second frame of the upstream support by the sheet (e.g.,
generally only by the sheet) in the compressed state (e.g.,
assemblies 202, 302, 342 and 552) and/or in the expanded state
(e.g., assemblies 202 and 552). As used in the present application,
including in the claims, (a) the first and second frames being
"coupled by the sheet", and/or (b) the sheet "coupling the first
frame to the second frame", do not include applications in which
the frames are primarily and/or independently coupled to each other
by a different means, and the covering extends over both frames.
For example, the first and second frames are not "coupled to each
other by the sheet" (1) in assemblies 382, 402 and 422, in which
the frames are provided pre-coupled directly to each other, or (2)
in the expanded state of assemblies 302 and 342, in which the
frames are intracorporeally coupled directly to each other.
[0585] For applications in which the first frame of the valve body
is coupled to the second frame of the upstream support by the
sheet, a gap typically exists between the first frame and the
second frame. For some such applications, no metallic structure is
disposed within the gap.
[0586] For some applications (including some applications in which
the first and second frames are coupled independently of the
sheet), the flexible sheet comprises, in addition to the sheet-like
structure, one or more flexible longitudinal members, such as
metallic or polymer wires (e.g., embedded within or attached to a
surface of the sheet-like structure). These flexible longitudinal
members may provide a small amount of rigidity to the sheet without
detracting from the general nature of the sheet. For example, the
flexible longitudinal members may facilitate opening of the sheet
during deployment of the prosthetic valve assembly.
[0587] It is to be noted that for applications in which the first
and second frames are coupled by the sheet, even when the sheet
comprises flexible longitudinal members that are metallic wires,
the frame of the valve body and the frame of the upstream support
are typically distinct from each other, and can be considered to be
coupled to each other by the sheet (e.g., generally only by the
sheet).
[0588] For some applications, within the total height of the
prosthetic valve assembly, a distance exists within which no rigid
and/or metallic structure is disposed. For example, for assembly
552, typically no rigid and/or metallic structure is disposed
within distance d17 and/or distance d19. It is to be noted that a
similar distance exists for assembly 202 between frames 210 and 206
(e.g., when implanted; see FIGS. 8F-G). For some applications, for
assembly 552, only sheet 564 and tethers 582 are disposed within
distances d17 and d19. However, for some applications,
tissue-engaging elements 580 extend proximally toward frame 562
such that the distance in which no rigid and/or metallic structure
is disposed is reduced and/or absent (e.g., when tethers 582 are
tensioned).
[0589] Reference is again made to FIGS. 1A-F, 3A-C, 6 and 7A-8H.
For some applications of the invention, tissue anchor 48 and/or the
guide member coupled thereto (e.g., guide member 56, guide member
256, and/or the components thereof) are included as components of
the provided apparatus. That is, they are typically provided with
the prosthetic valve assembly. For some applications of the
invention, the tissue anchor and/or the guide member coupled
thereto are not included as components of the provided apparatus
(e.g., they are obtained separately).
[0590] It will be understood that, although the terms "first,
"second," etc. may be used in the present application (including
the specification and the claims) to describe various elements
and/or directions, these terms should not be limiting. These terms
are only used to distinguish one element and/or direction from
another. Thus, a "first" element described herein could also be
termed a "second" element without departing from the teachings of
the present disclosure.
[0591] As used in the present application, including in the claims,
a "central longitudinal axis" of a structure (e.g., an elongate
structure) is the set of all centroids of transverse
cross-sectional sections of the structure along the structure. Thus
the cross-sectional sections are locally perpendicular to the
central longitudinal axis, which runs along the structure. (If the
structure is circular in cross-section, the centroids correspond
with the centers of the circular cross-sectional sections.)
[0592] It will be appreciated by persons skilled in the art that
the present invention is not limited to what has been particularly
shown and described hereinabove. Rather, the scope of the present
invention includes both combinations and subcombinations of the
various features described hereinabove, as well as variations and
modifications thereof that are not in the prior art, which would
occur to persons skilled in the art upon reading the foregoing
description.
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