U.S. patent application number 14/197690 was filed with the patent office on 2014-09-18 for prosthesis for atraumatically grasping intralumenal tissue and methods of delivery.
This patent application is currently assigned to CardiAQ Valve Technologies, Inc.. The applicant listed for this patent is CardiAQ Valve Technologies, Inc.. Invention is credited to Luca Pesce, Arshad Quadri, J. Brent Ratz.
Application Number | 20140277427 14/197690 |
Document ID | / |
Family ID | 50289392 |
Filed Date | 2014-09-18 |
United States Patent
Application |
20140277427 |
Kind Code |
A1 |
Ratz; J. Brent ; et
al. |
September 18, 2014 |
PROSTHESIS FOR ATRAUMATICALLY GRASPING INTRALUMENAL TISSUE AND
METHODS OF DELIVERY
Abstract
A prosthesis can comprise an expandable frame, a plurality of
distal anchors and a plurality of proximal anchors. The anchors can
extend outwardly from the frame. The frame can be configured to
radially expand and contract for deployment within a body cavity.
The frame and anchors can have one of many different shapes and
configurations. For example, when the frame is in an expanded
configuration, the frame can have a larger cross-sectional
dimension in a middle portion of the frame and a smaller
cross-sectional dimension in a proximal portion and a distal
portion of the frame, wherein the middle portion is between the
proximal and distal portions. As another example, the anchors can
have looped ends, the entire anchor may loop out from the
frame.
Inventors: |
Ratz; J. Brent; (Winchester,
MA) ; Quadri; Arshad; (West Hartford, CT) ;
Pesce; Luca; (Huntington Beach, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CardiAQ Valve Technologies, Inc. |
Irvine |
CA |
US |
|
|
Assignee: |
CardiAQ Valve Technologies,
Inc.
Irvine
CA
|
Family ID: |
50289392 |
Appl. No.: |
14/197690 |
Filed: |
March 5, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61782707 |
Mar 14, 2013 |
|
|
|
Current U.S.
Class: |
623/2.38 |
Current CPC
Class: |
A61F 2/2418 20130101;
A61F 2/2457 20130101; A61F 2/2409 20130101; A61F 2220/0008
20130101 |
Class at
Publication: |
623/2.38 |
International
Class: |
A61F 2/24 20060101
A61F002/24 |
Claims
1-31. (canceled)
32. A prosthesis configured to atraumatically engage intralumenal
tissue when deployed within a body cavity, the prosthesis
comprising: an expandable frame comprising a proximal end and a
distal end and having a longitudinal axis extending between the
proximal end and the distal end, the frame configured to radially
expand and contract for deployment within the body cavity; and a
plurality of distal anchors each connected to the frame at a base
and having a looped atraumatic end; wherein when the frame is in an
expanded configuration: each of the plurality of distal anchors
extends from the base generally distally before extending generally
proximally and radially outwardly from the frame; and the looped
atraumatic end of each distal anchor is circumferentially aligned
with the base where the distal anchor connects to the frame so that
the looped atraumatic end and the base are both located within a
common plane that is parallel to and intersects the longitudinal
axis.
33. The prosthesis of claim 32, wherein the frame comprises a
plurality of cells formed by interconnected struts.
34. The prosthesis of claim 33, wherein when the frame is in an
expanded configuration, a width of each of the plurality of distal
anchors as defined circumferentially around the longitudinal axis
over the entire length of the distal anchor from the base to the
looped atraumatic end is less than the width of one cell.
35. The prosthesis of claim 33, wherein the base of each of the
plurality of distal anchors is at a location where corners of two
adjacent cells meet.
36. The prosthesis of claim 33, wherein the base of each of the
plurality of distal anchors is at a distalmost corner of a
cell.
37. The prosthesis of claim 33, wherein adjacent looped ends of the
plurality of distal anchors are spaced apart by at least one
cell.
38. The prosthesis of claim 32, further comprising a plurality of
proximal anchors each connected to the frame, wherein when the
frame is in an expanded configuration an end of each of the
plurality of proximal anchors is positioned radially outward from
the frame and extends generally distally so that the ends of the
plurality of distal anchors are axially spaced from the ends of the
proximal anchors, and wherein the frame is configured such that
radial expansion of the frame causes ends of the plurality of
proximal anchors and the ends of the plurality of distal anchors to
draw closer together.
39. The prosthesis of claim 38, wherein the ends of the plurality
of distal anchors are positioned radially outward from the ends of
the plurality proximal anchors when the frame is in an expanded
configuration.
40. The prosthesis of claim 38, wherein the ends of the plurality
of distal anchors are not circumferentially aligned with the ends
of the plurality proximal anchors when the frame is in an expanded
configuration.
41. The prosthesis of claim 38, wherein the plurality of proximal
anchors each comprises a single arm that terminates in an
atraumatic tip.
42. The prosthesis of claim 32, further comprising a valve body
attached to the frame.
43. The prosthesis of claim 32, further comprising a layer of
resilient material covering each of the looped ends to facilitate
in-growth of adjacent tissue when the prosthesis is deployed within
a body cavity.
44. The prosthesis of claim 32, wherein when the frame is in an
expanded configuration, the frame has a larger cross-sectional
dimension in a middle portion of the frame and a smaller
cross-sectional dimension in a proximal portion and a distal
portion of the frame, wherein the middle portion is between the
proximal and distal portions.
45. The prosthesis of claim 44, wherein the plurality of distal
anchors extend from the distal portion of the frame and are
configured so that when the frame is in an expanded configuration,
each distal anchor of the plurality of distal anchors has an end
positioned radially outward from the middle portion of the
frame.
46. The prosthesis of claim 44, wherein the proximal end and the
distal end have substantially the same cross-sectional
dimension.
47. A prosthesis configured to atraumatically engage intralumenal
tissue when deployed within a body cavity, the prosthesis
comprising: an expandable frame comprising a proximal end and a
distal end and having a longitudinal axis extending between the
proximal end and the distal end, the frame configured to radially
expand and contract for deployment within the body cavity; and a
plurality of distal anchors each connected to the frame at a base
and having a looped atraumatic end, wherein each of the plurality
of distal anchors is connected to the frame with a single strut;
wherein when the frame is in an expanded configuration each of the
plurality of distal anchors extends from the base generally
distally before extending generally proximally and radially
outwardly from the frame.
48. The prosthesis of claim 47, wherein the frame comprises a
plurality of foreshortening cells, and each of the plurality of
distal anchors is connected to the frame with a single strut
extending from one of the cells.
49. The prosthesis of claim 48, wherein the frame comprises a
foreshortening portion and a non-foreshortening portion, wherein
the foreshortening portion comprises the plurality of
foreshortening cells and is distal to the non-foreshortening
portion.
50. The prosthesis of claim 49, further comprising a plurality of
proximal anchors extending radially outward from the
non-foreshortening portion of the frame when the frame is in an
expanded configuration.
51. The prosthesis of claim 47, wherein when the frame is in an
expanded configuration, the frame has a larger cross-sectional
dimension in a middle portion of the frame and a smaller
cross-sectional dimension in a proximal portion and a distal
portion of the frame, wherein the middle portion is between the
proximal and distal portions.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of priority to U.S.
Provisional Appl. Nos. 61/782,707, filed Mar. 14, 2013. The entire
contents of the above application(s) is/are hereby incorporated by
reference and made a part of this specification. Any and all
priority claims identified in the Application Data Sheet, or any
correction thereto, are hereby incorporated by reference under 37
CFR 1.57.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] Certain embodiments disclosed herein relate generally to
prostheses for implantation within a lumen or body cavity. In
particular, certain embodiments relate to expandable prostheses
such as replacement heart valves, such as for the mitral valve,
that are configured to atraumatically grasp intralumenal
tissue.
[0004] 2. Description of the Related Art
[0005] Human heart valves, which include the aortic, pulmonary,
mitral and tricuspid valves, function essentially as one-way valves
operating in synchronization with the pumping heart. The valves
allow blood to flow downstream, but block blood from flowing
upstream. Diseased heart valves exhibit impairments such as
narrowing of the valve or regurgitation, which inhibit the valves'
ability to control blood flow. Such impairments reduce the heart's
blood-pumping efficiency and can be a debilitating and life
threatening condition. For example, valve insufficiency can lead to
conditions such as heart hypertrophy and dilation of the ventricle.
Thus, extensive efforts have been made to develop methods and
apparatuses to repair or replace impaired heart valves.
[0006] Prostheses exist to correct problems associated with
impaired heart valves. For example, mechanical and tissue-based
heart valve prostheses can be used to replace impaired native heart
valves. More recently, substantial effort has been dedicated to
developing replacement heart valves, particularly tissue-based
replacement heart valves that can be delivered with less trauma to
the patient than through open heart surgery. Replacement valves are
being designed to be delivered through minimally invasive
procedures and even percutaneous procedures. Such replacement
valves often include a tissue-based valve body that is connected to
an expandable frame that is then delivered to the native valve's
annulus.
[0007] Development of prostheses including but not limited to
replacement heart valves that can be compacted for delivery and
then controllably expanded for controlled placement has proven to
be particularly challenging. An additional challenge relates to the
ability of such prostheses to be secured relative to intralumenal
tissue, e.g., tissue within any body lumen or cavity, in an
atraumatic manner. Further challenges arise when trying to
controllably deliver and secure such prostheses in a location such
as at a native mitral valve.
SUMMARY OF THE INVENTION
[0008] Embodiments of the present disclosure are directed to a
prosthesis, such as but not limited to a replacement heart valve.
Further embodiments are directed to methods of delivering a
prosthesis into a body cavity and/or securing a prosthesis to
intralumenal tissue. In some embodiments, a replacement heart valve
and methods for delivering a replacement heart valve to a native
heart valve, such as a mitral valve, are provided.
[0009] In some embodiments a prosthesis can comprise an expandable
frame, a plurality of distal anchors and a plurality of proximal
anchors. The anchors can extend outwardly from the frame. The frame
can be configured to radially expand and contract for deployment
within the body cavity. In some embodiments, when the frame is in
an expanded configuration, the frame can have a larger
cross-sectional dimension in a middle portion of the frame and a
smaller cross-sectional dimension in a proximal portion and a
distal portion of the frame, wherein the middle portion is between
the proximal and distal portions. In some embodiments, at least
some of the anchors comprise a loop that forms an atraumatic end of
a corresponding anchor.
[0010] In some embodiments, a prosthesis can be configured to
atraumatically grasp intralumenal tissue when deployed within a
body cavity. The prosthesis can comprise an expandable frame
comprising a proximal end and a distal end and having a
longitudinal axis extending between the proximal end and the distal
end. The frame can be configured to radially expand and contract
for deployment within the body cavity, wherein when the frame is in
an expanded configuration, the frame has a larger cross-sectional
dimension in a middle portion of the frame and a smaller
cross-sectional dimension in a proximal portion and a distal
portion of the frame, wherein the middle portion is between the
proximal and distal portions. The prosthesis can also include a
plurality of generally distally extending anchors extending from
the proximal portion of the frame and configured so that when the
frame is in an expanded configuration each distally extending
anchor has an end positioned radially outward from the middle
portion of the frame, and a plurality of generally proximally
extending anchors extending from the distal portion of the frame
and configured so that when the frame is in an expanded
configuration each proximally extending anchor has an end
positioned radially outward form the middle portion of the frame
and axially spaced from the ends of the distally extending anchors.
At least some of the anchors can comprise a loop that forms an
atraumatic end of the anchor The frame can be configured such that
radial expansion of the frame causes the ends of the plurality of
distally extending anchors and the ends of the plurality of
proximally extending anchors to draw closer together.
[0011] A prosthesis according to certain embodiments can be
configured to atraumatically grasp intralumenal tissue when
deployed within a body cavity. The prosthesis can comprise an
expandable frame, a plurality of proximal anchors each connected to
the frame so that when the frame is in an expanded configuration an
end of each proximal anchor is positioned radially outward from the
frame and extends generally distally, and a plurality of distal
anchors each connected to the frame so that when the frame is in an
expanded configuration an end of each distal anchor is positioned
radially outward from the frame and extends generally proximally,
wherein the ends of the distal anchors are axially spaced from the
ends of the proximal anchors when the frame is in an expanded
configuration. In some embodiments, at least some of the anchors
can comprise a looped end.
[0012] Alternatively, or in addition, in some embodiments, at least
some of the anchors can comprise a loop. Each loop of these later
embodiments can comprise first through fourth segments and an
arcuate segment. The first and second segments can both extend in a
first generally axial direction away from the frame. The third and
fourth segments can extend radially outward from the frame in a
second direction generally opposite the first direction, the third
segment connected to the first segment and the fourth segment
connected to the second segment. The arcuate segment can connect
the third segment and the fourth segment that forms an atraumatic
end of a corresponding anchor. In some embodiments, the frame is
configured such that radial expansion of the frame causes the ends
of the plurality of proximal anchors and the ends of the plurality
of distal anchors to draw closer together.
[0013] In some embodiments, a prosthesis can be configured to
atraumatically grasp intralumenal tissue when deployed within a
body cavity. The prosthesis can comprise an expandable frame, a
plurality of proximal anchors, and a plurality of distal anchors.
The expandable frame can comprise a proximal end and a distal end
and having a longitudinal axis extending between the proximal end
and the distal end, the frame configured to radially expand and
contract for deployment within the body cavity. The plurality of
proximal anchors can each connect to the frame so that when the
frame is in an expanded configuration an end of each proximal
anchor is positioned radially outward from the frame and extends
generally distally. The plurality of distal anchors can each
connect to the frame so that when the frame is in an expanded
configuration an end of each distal anchor is positioned radially
outward from the frame and extends generally proximally, wherein
the ends of the distal anchors are axially spaced from the ends of
the proximal anchors when the frame is in an expanded
configuration. At least some of the anchors can comprise a loop.
Each of the anchors that comprises a loop can comprise at least a
first segment extending in a first generally axial direction away
from the frame, and a second segment and a third segment extending
radially outward from the frame in a second direction generally
opposite the first direction and coming together in an atraumatic
end. The frame can be configured such that radial expansion of the
frame causes the ends of the plurality of proximal anchors and the
ends of the plurality of distal anchors to draw closer
together.
[0014] According to some embodiments a prosthesis can be configured
to atraumatically grasp intralumenal tissue when deployed within a
body cavity. The prosthesis can comprise an expandable frame
comprising a proximal end and a distal end and having a
longitudinal axis extending between the proximal end and the distal
end, the frame configured to radially expand and contract for
deployment within the body cavity, a plurality of proximal anchors
each connected to the frame so that when the frame is in an
expanded configuration an end of each proximal anchor is positioned
radially outward from the frame and extends generally distally, and
a plurality of distal anchors each connected to the frame so that
when the frame is in an expanded configuration an end of each
distal anchor is positioned radially outward from the frame and
extends generally proximally, wherein the ends of the distal
anchors are axially spaced from the ends of the proximal anchors
when the frame is in an expanded configuration. At least some of
the anchors can comprise a loop and each loop can comprise first
through fourth segments and an arcuate segment. The first and
second segments can both extend in a first generally axial
direction away from the frame. The third and fourth segments can
extend radially outward from the frame in a second direction
generally opposite the first direction, the third segment connected
to the first segment and the fourth segment connected to the second
segment. The arcuate segment can connect the third segment and the
fourth segment that forms an atraumatic end of a corresponding
anchor. The frame can be configured such that radial expansion of
the frame causes the ends of the plurality of proximal anchors and
the ends of the plurality of distal anchors to draw closer
together.
[0015] Methods of delivering a prosthesis and/or securing the
prosthesis to intralumenal tissue are also provided. In one
embodiment, a method of delivering a replacement valve to a native
mitral valve can comprise one or more of the following steps.
Delivering a replacement valve mounted on a delivery device to the
native mitral valve annulus while the replacement valve is in a
radially compacted state, the replacement valve comprising a
radially expandable frame comprising a proximal end, a distal end,
a plurality of distal anchors extending generally proximally from
the frame, and a plurality of proximal anchors extending generally
distally from the frame. Positioning the replacement valve so that
ends of the distal anchors are on a ventricular side of the native
leaflets beyond a location where chordae tendineae connect to free
ends of the native leaflets. Releasing at least a portion of the
replacement valve from the delivery device to thereby expand the
distal anchors radially outwardly to a first radial dimension.
Moving the ends of the distal anchors toward the ventricular side
of the native valve annulus with the distal anchors extending
between at least some of the chordae tendineae to provide tension
on the chordae tendineae. Further releasing the replacement valve
from the delivery device to thereby expand the proximal anchors
radially outwardly to a second radial dimension greater than the
first radial dimension, wherein the proximal anchors upon further
release of the replacement valve from the delivery device move into
engagement with tissue on an atrial side of the native valve
annulus while the distal anchors provide tension on the chordae
tendineae.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] These and other features, aspects and advantages are
described below with reference to the drawings, which are intended
to illustrate but not to limit the invention. In the drawings, like
reference characters denote corresponding features consistently
throughout similar embodiments.
[0017] FIG. 1A is a side view of an embodiment of a prosthesis.
[0018] FIG. 1B is a flat pattern view of the prosthesis of FIG.
1A.
[0019] FIG. 2A is a side view of an embodiment of a prosthesis.
[0020] FIG. 2B is a flat pattern view of the prosthesis of FIG.
2A.
[0021] FIG. 3A is a side view of an embodiment of a prosthesis.
[0022] FIG. 3B is a flat pattern view of the prosthesis of FIG.
3A.
[0023] FIG. 4 is a side view of an embodiment of a prosthesis.
[0024] FIG. 5 is a side view of an embodiment of a prosthesis.
[0025] FIG. 6A is a side view of an embodiment of a prosthesis
configured as a replacement heart valve.
[0026] FIG. 6B is a bottom view of the prosthesis similar of FIG.
6A.
[0027] FIG. 7 is a side view of an embodiment of a prosthesis
configured as a replacement heart valve.
[0028] FIG. 8A is a side view of an embodiment of a prosthesis.
[0029] FIG. 8B is a detail view of a portion of the prosthesis of
FIG. 8A.
[0030] FIG. 9A is a side view of an embodiment of a prosthesis.
[0031] FIG. 9B is a bottom view of the prosthesis of FIG. 9A,
configured as a replacement heart valve.
[0032] FIG. 10 is a schematic representation of a prosthesis
positioned within the heart.
[0033] FIG. 10A is a detail schematic representation of the
prosthesis positioned within the heart of FIG. 10.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0034] The present specification and drawings provide aspects and
features of the disclosure in the context of several embodiments of
prostheses, replacement heart valves, delivery devices and methods
that are configured for use in the vasculature of a patient, such
as for replacement of natural heart valves in a patient. These
embodiments may be discussed in connection with replacing specific
valves such as the patient's aortic or mitral valve. However, it is
to be understood that the features and concepts discussed herein
can be applied to products other than heart valve implants. For
example, the controlled positioning, deployment, and securing
features described herein can be applied to medical implants, for
example other types of expandable prostheses, for use elsewhere in
the body, such as within a vein, or the like. In addition,
particular features of a valve, delivery device, etc. should not be
taken as limiting, and features of any one embodiment discussed
herein can be combined with features of other embodiments as
desired and when appropriate.
[0035] With initial reference to FIG. 1A, an embodiment of a
prosthesis 10 is shown. The illustrated prosthesis 10 includes a
frame 20 that may be self-expanding or balloon expandable. The
prosthesis may further include a replacement valve that can be
designed to replace a damaged or diseased native heart valve such
as a mitral valve. The replacement valve is not shown in this
embodiment as to more clearly illustrate features of the frame 20,
though it will be understood that a replacement valve is not
required as part of the prosthesis. In addition, it will be
understood that only a front portion of the frame 20 is shown for
further ease of illustration.
[0036] The frame 20 can be made of many different materials, but is
preferably made from metal. In some embodiments, the frame 20 can
be made from a shape memory material, such as nitinol. A wire frame
or a metal tube can be used to make the frame. The wire frame of a
metal tube can be cut or etched to remove all but the desired metal
skeleton. In some embodiments a metal tube is laser cut in a
repeating pattern to form the frame. FIG. 1B illustrates the flat
cut pattern of the frame shown in FIG. 1A. The flat pattern can be
cut from a metal tube and then the tube can be bent and expanded to
the shape shown in FIG. 1A. The frame 20 can further be expanded
and/or compressed and/or otherwise worked to have the desired shape
or shapes, such as for introduction and implantation.
[0037] As shown, the frame when in an expanded configuration, such
as in a fully expanded configuration, has a bulbous or slightly
bulbous shape, with a middle portion being larger than the proximal
32 and distal 34 ends. In some embodiments, the inside diameter of
the both ends can be the same, or it can be bigger on one end than
the other, while still having a middle portion larger than both the
proximal and distal ends. In some embodiments, the effective
diameter of the distal frame end is smaller than the effective
diameter of the middle portion. The bulbous shape of the frame can
advantageously allow the frame to engage a native valve annulus or
other body cavity, while spacing the inlet and outlet from the
heart or vessel wall. This can help reduce undesired contact
between the prosthesis and the heart or vessel, such as the
ventricular wall of the heart. In other embodiments, the frame may
not have a bulbous portion, and can have substantially the same
outer dimension along its entire length, or it may have one end
larger than the other end. The prosthesis 10 and frame 20 may be
similar to the replacement heart valves and associated frames
disclosed in U.S. Pat. No. 8,403,983 and U.S. Publication Nos.
2010/0298931, 2011/0313515 and 2012/0078353 the entireties of each
of which are hereby incorporated by reference and made a part of
this specification. This is inclusive of the entire disclosure and
is not in any way limited to the disclosure of the replacement
heart valves and associated frames.
[0038] A number of struts collectively make up the frame 20. FIG. 1
illustrates the frame in an expanded configuration with a number of
longitudinal struts 12 and undulating struts 14, with cells defined
by the open spaces between the struts. The longitudinal struts may
be arranged so that they are parallel or generally or substantially
parallel to a longitudinal axis of the frame. The longitudinal axis
of the frame may be defined as the central axis that extends
through the center of the frame between the proximal 32 and distal
34 ends. Any number of configurations of struts can be used, such
as the rings of undulating struts shown forming chevrons and
diamonds, but also ovals, curves, and various other shapes. The
illustrated embodiment includes two rings, or rows of chevrons
shown in portion 16 and two rows of diamond-shaped cells shown in
portion 18.
[0039] The frame 20 has a non-foreshortening portion 16 and a
foreshortening portion 18. These portions can be defined by the
frame 20 and the positioning of various types of struts along the
frame 20. In FIG. 1 it can be seen that the longitudinal struts 12
span the length of the non-foreshortening portion 16, while
undulating struts 14 form the foreshortening portion 18. When the
frame is radially collapsed or compacted, the struts 14 become more
parallel with respect to the longitudinal axis of the frame,
causing an outer diameter of the frame to decrease and the
longitudinal length of the frame to increase in the foreshortening
portion 18. As the frame moves from a compacted position to an
expanded position, the longitudinal length of the frame can
decrease in the foreshortening portion 18. But, the frame length
does not substantially change length in the non-foreshortening
portion 16.
[0040] Foreshortening of the frame 20 can be used to engage and
secure the prosthesis to intralumenal tissue in a body cavity, for
example tissue at or adjacent a native valve, such as a native
valve annulus and/or leaflets. Opposing anchors 22, 24 can be
constructed on the frame 20 so that portions of the anchors, such
as tips or ends 26, 28, move closer together as the frame
foreshortens. As one example, this can allow the anchors 22, 24 to
grasp tissue on opposite sides of the native mitral annulus to
thereby secure the prosthesis at the mitral valve.
[0041] The anchors 22, 24 and anchor tips 26, 28 can be located
anywhere along the frame 20 just so long as at least one of the
anchors is either connected to the foreshortening portion 18 or the
foreshortening portion is positioned between the anchors so that a
portion of the anchors will be move closer together with expansion
of the frame. As shown, the anchors 24 are connected to the
foreshortening portion 18. The foreshortening portion can also be
positioned anywhere along the frame, though it is shown towards the
distal end 34. In some embodiments, both of the anchor tips 26, 28
are located in the foreshortening portion 18. In some embodiments,
the foreshortening portion 18 may extend the entire length of the
frame, such that there is no non-foreshortening portion 16.
[0042] Preferably, each of the anchors 22, 24 is positioned or
extends generally radially outwardly from the frame 20 so that the
anchor tips 26, 28 are generally spaced away or radially outward
from the rest of the frame 20. For example, the anchor tips may be
located radially outward from the middle portion of the frame, with
the tips 26 and 28 being axially spaced from one another. In some
embodiments, all or part of the structure connected to the anchor
tip and extending radially from the frame, including one or more
rings and/or struts, can be considered part of the anchor. The
anchors can include a base located on the anchor on a side opposite
the tip. The base can be for example where the anchor begins to
extend from or away from the frame 20.
[0043] For example, proximal anchors 22 are shown having first 36
and second 38 struts forming a chevron and connected to
longitudinal struts 12 at a base of the anchor. The first and
second struts of the anchor 22 are bent at the base so that the
anchor 22 extends radially outwardly from the frame as it extends
generally distally towards the tip 26. The first and second struts
can be connected to each other at a radially outward location to
form an outwardly extending loop, and in some embodiments, the
first and second struts can be joined at a third strut 40 that
continues to extend outwardly and/or generally distally. Here the
third strut 40 is a short strut. The anchor also includes an eyelet
46. As illustrated, the eyelet is located at the distal end 26,
though the eyelet can be positioned in other locations along the
anchor 22. The tips 26 of the proximal anchors may extend distally
and be parallel or substantially parallel with the longitudinal
axis of the frame, or as illustrated in FIG. 1A, the tips 26 may
extend generally distally but still radially outwardly inclined or
at an acute angle relative to the longitudinal axis of the
frame.
[0044] As another example, the distal anchors 24 are shown having
looped ends 48. The looped ends can be larger near the tip to form
a type of elongated teardrop. In addition, the tips 28 may be
substantially flat. The looped end may assist the frame in not
getting caught up on structures at or near the treatment location.
For example, each loop can be configured so that when the frame is
deployed in-situ and expands, the movement of each loop from a
delivered position to a deployed position can avoids getting caught
on the papillary muscles.
[0045] Each distal anchor 24 is connected to the frame at a base
42. As illustrated in FIG. 1A, the base of the distal anchor may be
at a location where the corners of adjacent cells meet, such that
the base is proximal to the distal end 34 of the frame. In other
embodiments, the base of the distal anchor may be at a distal most
corner of a cell, which corresponds to a distal most point on the
frame The distal anchors as illustrated extend from the base 42
generally distally before bending back around in an arcuate segment
where the distal anchor extends generally proximally and radially
outwardly from the frame. As shown, the anchors 24 may also
generally distally and radially inwardly with respect to the frame
such that the distal most point on the prosthesis has a smaller
inside diameter than where the base 42 connects to the frame. The
inside diameter at the distal most can be the same or substantially
the same as the inside diameter of the proximal end, or may be
smaller. The anchor as illustrated is bent around about 180 degrees
so that the tip 28 extends in the opposite, proximal direction,
which may be parallel or substantially parallel to the longitudinal
axis of the frame. For example, in FIG. 1A it can be seen that the
distal anchors 24 are bent further inward such that the ends of the
anchors point proximally and are generally parallel with the
longitudinal axis of the frame. Alternatively, the tip 28 may
extend generally proximally but still extend radially outwardly
inclined or at an acute angle relative to the longitudinal axis of
the frame
[0046] It will be understood that the anchors can have various
other configurations, including the various embodiments that
follow. In some embodiments, each of the anchors can extend
radially outwardly from the frame at an anchor base and terminate
at an anchor tip. The anchors can be connected to the frame at one
of many different locations including apices, junctions, other
parts of struts, etc. The anchors can comprise first, second,
third, or more spaced apart bending stages along the length of each
anchor. The anchors can also extend either distally or proximally
before and/or after one or more of the bending stages. A portion of
the anchor may extend with the frame before or after any bending
stages.
[0047] In the illustrated embodiment of FIG. 1A-B there are twelve
distal anchors and twelve proximal anchors. In some embodiments
there may be 6 anchors on one side and 12 on the other. Some
embodiments may include different numbers of anchors. In addition,
the distal and proximal anchors may be aligned so the tips point
generally towards each other, or they may be spaced so that the
tips point between two tips on the opposite side, as is illustrated
in FIGS. 1A-B.
[0048] The anchor tips 26 and 28 as described above advantageously
provide atraumatic surfaces that may be used to grasp intralumenal
tissue without causing unnecessary or undesired trauma to tissue.
For example, the proximal anchors tips 26 and distal anchor tips 28
may form flat, substantially flat, curved or other non-sharp
surfaces to allow the tips to engage and/or grasp tissue, without
necessarily piercing or puncturing through tissue.
[0049] FIGS. 2A-3B show prostheses similar to that of FIGS. 1A-B
with two different styles of distal anchors 24. In FIGS. 2A-B, the
looped end 48' of the distal anchor is generally more elliptical
with a curved tip as compared to the elongated teardrop shape of
looped end 48 of FIGS. 1A-B. Otherwise the shape is substantially
the same.
[0050] In FIGS. 3A-B, the distal anchors 24 are looped anchors
rather than having looped ends. The looped anchor has a first base
42 and a second base 44 connected to the frame, wherein the first
and second bases are at opposite corners of the same cell.
Alternatively, the first and second bases may be located at the
distal most corners of adjacent cells. The distal anchors 24
extends generally distally from the frame at the first base 42 but
then is bent back around and begins to extend outwardly from the
frame in a generally proximal direction. The distal anchor 24 then
repeats this configuration in reverse towards the second base 44
such that the two sides of the looped anchor are mirror images of
one another. It will be understood that the looped anchor can have
other configurations and that it may not be symmetrical.
[0051] As illustrated in FIG. 3A, the tips 28 of the distal anchors
are circumferentially aligned with the tips 26 of the proximal
anchors, though in other embodiments, the tips 28 of the distal
anchors may be circumferentially staggered between the tips 26 of
the proximal anchors. In the embodiment of FIG. 3A, adjacent distal
anchors 26 are spaced apart by one cell, though in other
embodiments, adjacent distal anchors may be provided on adjacent
cells. Thus, for example, instead of having six distal anchors and
twelve proximal anchors as shown in FIG. 3A, there may be a 1:1
correspondence between proximal and distal anchors.
[0052] The illustrated looped distal anchor of FIGS. 3A-B is made
up of the following segments. The first segment 50 extends
generally longitudinally with the frame, extending distally or
generally distally (e.g., slightly radially inward) with the frame.
The strut is then bent so that a second segment 52 extends
generally parallel with an adjacent undulating strut 14. The strut
is then bent so that a third segment 54 begins to extend generally
longitudinally and distally or generally distally, and then is bent
back around to point in generally the opposite direction (e.g., in
a proximal direction parallel or generally parallel with the
longitudinal axis of the frame). The third segment 54 ends in the
rounded tip 28 and then the anchor strut repeats to form the mirror
image. After the third segment 54 bends back around to point in
generally the opposite direction, in the embodiment illustrated the
third segment may first extend radially outward at an acute angle
relative to the longitudinal axis before bending into a portion
that extends parallel or substantially parallel to the longitudinal
axis. The paired third segments 54 extend parallel or generally
parallel with one another from the second segment to the tip,
though they may also move slightly towards or away from each other
in some embodiments.
[0053] FIG. 4 shows a prosthesis similar to FIGS. 3A-B that also
has looped distal anchors. In this embodiment the first segment 50
extends longitudinally in a distal direction from the frame and the
strut is bent back on itself to point generally in the opposite
(e.g., proximal) direction. The second segment is bent inward
before extending parallel or generally parallel with its mirror
image on the other side forming a nose and wing configuration
similar to the shape of certain bicycle seats.
[0054] The proximal anchors 22 also have an elongated third strut
40. The proximal anchor 22 is shown having first 36 and second 38
struts forming a chevron and connected to longitudinal struts 12 at
a base of the anchor. The first and second struts of the anchor 22
are bent at the base so that the anchor 22 extends radially
outwardly from the frame as it extends towards the tip 26. The
first and second struts join at a third strut 40 that continues to
extend outwardly and is then bent such that the tip points distally
and extends in a manner parallel or generally parallel with the
longitudinal axis of the frame. The proximal anchor may or may not
include an eyelet 46 along its length. The distal tip of the
proximal anchors may have an atraumatic surface, such as an
enlarged circular or curved end as illustrated. When the frame is
in an expanded configuration, the distal anchors 24 may have tips
28 that are positioned radially outward of the tips 26 of the
proximal anchors 22. Other embodiments may have the tips 26 being
positioned outward of the tips 28. Such configurations are also
possible with the other frames and prostheses described elsewhere
herein.
[0055] FIG. 5 illustrated an embodiment similar to the prosthesis
of FIG. 4 with twelve distal anchors instead of six. Because of
this change, in one embodiment two anchors share the first segment
50 where the anchor base 42, 44 is connected to the frame. As
illustrated, each of the proximal and distal anchors may be
circumferentially aligned with each other, and each of the distal
anchors corresponds to one of the cells
[0056] Turning now to FIGS. 6A-B, prosthesis and frame embodiments
are shown similar to that of FIG. 4, including various other
components of the prosthesis. A prosthesis can include one or more
of a valve 60, a skirt 70 and a support band 80. The prosthesis can
be a replacement heart valve similar to that and including features
similar to those disclosed in U.S. patent application Ser. Nos.
13/165,721, filed Jun. 21, 2011, published as U.S. 2011/0313515;
and 13/244,080, filed Sep. 23, 2011, published as 2012/0078353. The
entire contents of both applications are hereby incorporated by
reference herein and made a part of this specification. This is
inclusive of the entire disclosure and is not in any way limited to
the disclosure of the replacement heart valve.
[0057] The valve 60 can be a replacement heart valve which includes
a plurality of valve leaflets 62. The plurality of valve leaflets
62 can function in a manner similar to the natural mitral valve, or
to other valves in the vascular system. The plurality of valve
leaflets 62 can open in a first position and then engage one
another to close the valve in a second position. The plurality of
valve leaflets 62 can be made to function as a one way valve such
that flow in one direction opens the valve and flow in a second
direction opposite the first direction closes the valve. The
replacement heart valve 60 can be constructed so as to open
naturally with the beating of the heart. For example, the plurality
of valve leaflets 62 can open during diastole and close during
systole.
[0058] In some embodiments, the leaflets 62 can be coupled to a
skirt 70. For example, the proximal ends of the leaflets 62 can be
connected to a proximal end of the skirt 70.
[0059] The skirt 70 can be used to at least partially control how
fluid flows through and/or around the valve 60. The skirt 70 can
surround at least a portion of the valve and be connected to the
valve leaflets 62. In some embodiments, the skirt 70 can form an
inner wall connected to and positioned within the frame 20. The
skirt 70 can also be made to move with the foreshortening portion
18 of the frame 20.
[0060] The skirt 70 can extend the length of the frame 20 or it can
extend along only part of the length of the frame 20. In some
embodiments, the ends of the heart valve 60 can coincide with ends
of the skirt 70. In addition, one or more of the ends of the frame
20 can coincide with the ends of the skirt 70. In the illustrated
embodiment of FIGS. 6A-B, the proximal end of the skirt 70 and
heart valve 60 are sewn together. The skirt 70 can not only extend
to the distal end of the frame 20 but can also extend to the
outside of the frame and is shown wrapped around each of the distal
anchors 24.
[0061] Other shapes and configurations can also be used for the
valve 60 and skirt 70. In some embodiments, the skirt 70 may extend
along the length of the leaflets 62, but is not connected to them.
In the illustrated embodiments, the skirt 70 is attached to the
frame 20 and the leaflets 62 are attached to the skirt 70.
[0062] The skirt 70 can be constructed in multiple different ways.
The skirt 70 can be made of knit polyester or another stretchable
or flexible fabric. In some embodiments, the skirt 70 is made from
a material that is more flexible than the valve leaflet material.
The distal and/or proximal end of the skirt 70 can be straight,
curved, or have any other desired configuration. For example, the
skirt 70 is shown with undulations patterned to generally
correspond to the undulations at the distal end 34 of the frame 20.
It can be seen that the skirt 70 wraps around the struts at the
distal end. The skirt 70 can be formed of one piece or multiple
pieces. For example, the skirt 70 attached to the valve 60 can be
one piece and then each distal anchor can be covered by a separate
piece of material of the skirt 70. It is to be understood that
other configurations of the skirt 70 can also be employed. For
example, the anchors may remain uncovered, or only a portion may be
covered.
[0063] Turning now to FIG. 7, another embodiment of the skirt 70 is
shown. Here rather than the skirt 70 corresponding to the
undulations at the distal end 34 of the frame 20, the skirt extends
past the frame and is then wrapped around it. Thus, the skirt 70
extends from the inside of the frame 20 to the outside of the
frame. The skirt can extend completely around the frame for 1/4,
1/3, 1/2, or more of the length of the distal anchors. The skirt
can also cover the distal anchors 24. In the illustrated
embodiment, the skirt is a one piece skirt, but it will be
understood that the skirt can be made of multiple pieces.
[0064] The skirt 70, and particularly portions that cover the
distal anchors 24, can beneficially be used to help prevent leakage
of blood flow around the heart valve. In addition, the skirt can
encourage tissue in-growth between the skirt and the natural
tissue. This may further help to prevent leakage of blood flow
around the heart valve.
[0065] The prosthesis 10 can also include a support band 80 as is
shown in FIGS. 6A-7. The support band 80 may be placed or
positioned around or within the frame 20 at the proximal end 32.
The support band 80 can be used to reinforce and/or constrain the
frame 20. The support band 80 can help to control the expansion of
the frame 20 from the compacted to the expanded state. The support
band 80 can also be used to reduce the amount of motion that occurs
at the proximal end 32 after the prosthesis 10 has been implanted
at the mitral heart valve or other location.
[0066] In some embodiments, the support band 80 may comprise a
polyester fabric band. The support band 80 may comprise a
no-stretch or limited stretch material. Preferably the support band
80 is not made of an elastic material or a material known to have
high elasticity. In some embodiments, the support band 80 is made
from a material that is less flexible than the valve skirt material
and/or the valve leaflet material. The distal and proximal ends of
the support band 80 can be straight, curved, undulating with the
undulations of frame, or any other desired configuration.
[0067] The support band 80 can be connected to the valve frame with
a plurality of stitches, loops, knots, staples, or other types of
connections. In some embodiments, the frame 20 can be sandwiched
between two sides or layers of the support band 80. Preferably, the
support band 80 is a single layer positioned within and attached to
the frame 20 with a plurality of stitches around one or more of the
longitudinal and/or undulating struts. In some embodiments, the
support band 80 can be attached to the proximal end of the valve
skirt 40.
[0068] Looking now at FIGS. 8A-B another embodiment of a prosthesis
10 is shown. FIGS. 8A-B show a prosthesis similar to that of FIG. 4
with a different style and configuration of distal anchor 24. In
FIGS. 8A-B, the distal anchors are shorter than and spaced radially
inward from the distal anchors of FIG. 4. Thus, as illustrated, the
distal anchors 24 are not positioned as far radially outward as the
proximal anchors, and the tips 28 may be positioned radially inward
of the tips 26. As described further below, such a configuration
may be advantageous in positioning and securing the prosthesis in a
mitral valve or other body location. As shown particularly in FIG.
8B, the distal anchors 24 may comprise loops as described above,
having a curved or arcuate atraumatic tip to minimize damage to
body tissue.
[0069] FIGS. 9A-B show an embodiment of a prosthesis where the
distal anchors do not comprise loops, but instead comprise single
struts each extending distally from the corners where adjacent
cells meet. As described with respect to embodiments above, these
anchors may first extend distally or generally distally, and may
further extend radially inward, before bending around to extend
proximally or generally proximally, such as at an acute angle
relative to the longitudinal axis of the frame. The tips 28 of the
anchors may comprise an atraumatic surface, such as a flattened or
curved enlarged tip. As illustrated, the tips 28 may be
circumferentially staggered between tips 26 of the proximal anchors
22, as best shown in FIG. 9B. FIG. 9B also shows the frame 20
having a valve 60 and skirt 70 attached as described above.
[0070] In preferred embodiments, any of the prostheses 10 described
above may be deployed into a heart valve annulus, and positioned
when compacted so that the anchor tips 26, 28 of the opposing
anchors 22, 24 are disposed on opposite sides of the native annulus
88 as shown in FIGS. 10 and 10A. As the replacement heart valve 10
is expanded, the opposing anchors are drawn closer together so as
to grasp tissue on opposite sides of the native annulus 88 and
securely hold the replacement heart valve 10 in position. As such,
the replacement heart valve 10 can be held securely in position
without requiring a substantial radial force against the native
annulus. Because the anchor tips are preferably atraumatic, the
grasping or engaging of tissue by the prosthesis minimizes damage
to the native tissue. The foreshortening portion 18 can be used to
move the anchor tips 26, 28 closer together as the replacement
heart valve 10 moves to the expanded position to thereby engage the
native valve annulus. The prosthesis can be deployed into a heart
valve or otherwise deployed in manners similar to those described
with respect to a replacement heart valve in U.S. Publication No.
2010/0298931 and 2012/0078353 the entireties of each of which are
hereby incorporated by reference and made a part of this
specification. This is inclusive of the entire disclosure and is
not in any way limited to the disclosure related to deployment of a
replacement heart valve.
[0071] FIGS. 10 and 10A show a schematic representation of the
replacement heart valve 10 installed in a human heart 84. The heart
is shown in cross-section, and represents typical anatomy,
including a left atrium 78 and left ventricle 86. The left atrium
78 and left ventricle 86 communicate with one another through a
mitral annulus 88. Also shown schematically is a native anterior
mitral leaflet 90 having chordae tendineae 92 that connect a
downstream end of the anterior mitral leaflet 90 and to the left
ventricle 86.
[0072] In one preferred embodiment, a method is provided of
delivering a replacement valve to a native mitral valve and
atraumatically securing the replacement valve relative to the
native mitral valve annulus 88. The replacement valve can be
mounted on a delivery device and delivered to the native mitral
valve annulus while the replacement valve is in a radially
compacted state. The replacement valve may be positioned so that
the ends or tips of the distal anchors are on a ventricular side of
the native leaflets 90 beyond a location where chordae tendineae 92
connect to free ends of the native leaflets. At least a portion of
the replacement valve can be released from the delivery device to
thereby expand the distal anchors radially outwardly. At this time
the distal anchors may extend between at least some of the chordae.
The distal anchors (along with the frame) can be moved toward the
ventricular side of the native valve annulus with the distal
anchors extending between at least some of the chordae tendineae to
provide tension on the chordae tendineae. With tension provided on
the chordae tendineae, the replacement valve can be further
released from the delivery device to thereby expand the proximal
anchors radially outwardly. The proximal anchors upon further
release of the replacement valve from the delivery device can move
into engagement with tissue on an atrial side of the native valve
annulus, such as with the atrial side of the native valve
annulus.
[0073] The method just described may utilize any of the prostheses
herein described, but may be particularly suitable for the
prosthesis of FIGS. 8A-8B where the ends of the distal anchors are
not positioned as far out radially as the ends of the proximal
anchors when the frame is expanded. Thus, the distal anchors may
have a suitable length for extending between and providing tension
on the chordae tendineae, but need not and may not in some
embodiments engage tissue with the tips 28. Thus, in some
embodiments the some or all of the distal anchors remain spaced
from tissue on the ventricular side of the native valve annulus
after delivery and expansion. The interaction between the distal
anchors and the chordae tendineae may therefore be sufficient to
secure the distal end of the prosthesis, while the engagement of
the proximal anchors with tissue on the atrial side of the native
valve annulus will help further secure and orient the
prosthesis
[0074] As illustrated in FIGS. 10 and 10A, the distal anchors may
comprise loops, such as any of the looped structures previously
described. The distal anchors may also be covered with a resilient
material such as described above for the skirt 70 that promotes
tissue growth with adjacent body tissue. Such material may also be
useful to prevent paravalvular leakage. The atraumatic distal
anchors may advantageously prevent snagging of the prosthesis on
internal structures, such as the papillary muscles.
[0075] Although this invention has been disclosed in the context of
certain preferred embodiments and examples, it will be understood
by those skilled in the art that the present invention extends
beyond the specifically disclosed embodiments to other alternative
embodiments and/or uses of the invention and obvious modifications
and equivalents thereof. In addition, while a number of variations
of the invention have been shown and described in detail, other
modifications, which are within the scope of this invention, will
be readily apparent to those of skill in the art based upon this
disclosure. It is also contemplated that various combinations or
sub-combinations of the specific features and aspects of the
embodiments may be made and still fall within the scope of the
invention. Accordingly, it should be understood that various
features and aspects of the disclosed embodiments can be combined
with or substituted for one another in order to form varying modes
of the disclosed invention. Thus, it is intended that the scope of
the present invention herein disclosed should not be limited by the
particular disclosed embodiments described above, but should be
determined only by a fair reading of the claims that follow.
[0076] Similarly, this method of disclosure, is not to be
interpreted as reflecting an intention that any claim require more
features than are expressly recited in that claim. Rather, as the
following claims reflect, inventive aspects lie in a combination of
fewer than all features of any single foregoing disclosed
embodiment. Thus, the claims following the Detailed Description are
hereby expressly incorporated into this Detailed Description, with
each claim standing on its own as a separate embodiment.
* * * * *