U.S. patent application number 16/668315 was filed with the patent office on 2020-02-27 for low profile delivery system for transcatheter heart valve.
The applicant listed for this patent is Edwards Lifesciences Corporation. Invention is credited to Robert Bowes, Ronaldo C. Cayabyab, Thanh Huy Le, Walter Lee, Tram Ngoc Nguyen, David M. Taylor, Tri D. Tran, Antonio O. Vidal.
Application Number | 20200060822 16/668315 |
Document ID | / |
Family ID | 40886438 |
Filed Date | 2020-02-27 |
View All Diagrams
United States Patent
Application |
20200060822 |
Kind Code |
A1 |
Le; Thanh Huy ; et
al. |
February 27, 2020 |
LOW PROFILE DELIVERY SYSTEM FOR TRANSCATHETER HEART VALVE
Abstract
A method of delivery a prosthetic heart valve includes inserting
a delivery apparatus and a prosthetic heart valve into a patient's
vasculature. The delivery apparatus includes a steerable guide
catheter, a balloon catheter, and a flex indicator. The balloon
catheter extends coaxially through the guide catheter, the
prosthetic heart valve is mounted on a distal end portion of the
balloon catheter, and the flex indicator is movably coupled to a
handle of the guide catheter. The method further includes adjusting
flexion of a steerable section of the guide catheter to position
the prosthetic heart valve. The flex indicator moves relative to
the handle of the guide catheter as the flexion of the steerable
section is adjusted, and the handle comprises one or more visual
indicators adjacent the flex indicator to provide visual indication
of an amount of flexion of the steerable section of the guide
catheter.
Inventors: |
Le; Thanh Huy; (Oceanside,
CA) ; Tran; Tri D.; (Fountain Valley, CA) ;
Cayabyab; Ronaldo C.; (Mission Viejo, CA) ; Taylor;
David M.; (Lake Forest, CA) ; Vidal; Antonio O.;
(Tustin, CA) ; Bowes; Robert; (Trabuco Canyon,
CA) ; Nguyen; Tram Ngoc; (Santa Ana, CA) ;
Lee; Walter; (Irvine, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Edwards Lifesciences Corporation |
Irvine |
CA |
US |
|
|
Family ID: |
40886438 |
Appl. No.: |
16/668315 |
Filed: |
October 30, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16197244 |
Nov 20, 2018 |
10478296 |
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16668315 |
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14736117 |
Jun 10, 2015 |
10456253 |
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16197244 |
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12247846 |
Oct 8, 2008 |
9061119 |
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14736117 |
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61083117 |
Jul 23, 2008 |
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61052009 |
May 9, 2008 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61M 2025/0681 20130101;
A61M 25/1011 20130101; A61F 2/9517 20200501; A61M 2025/1093
20130101; A61M 2025/1081 20130101; A61M 25/0147 20130101; A61M
25/10 20130101; A61F 2/2436 20130101; A61M 25/0105 20130101; A61F
2/2418 20130101; A61F 2/2427 20130101; A61M 25/01 20130101; A61F
2/2433 20130101 |
International
Class: |
A61F 2/24 20060101
A61F002/24; A61M 25/01 20060101 A61M025/01; A61M 25/10 20060101
A61M025/10 |
Claims
1. A delivery apparatus, comprising: a handle; a first shaft
extending distally from the handle; an inflatable balloon disposed
on a distal end portion of the first shaft; a second shaft
extending distally from the handle over at least a portion of the
first shaft; and the second shaft comprising an expandable distal
end portion extending over a portion of the balloon; wherein the
distal end portion of the second shaft is configured to expand
radially when the balloon is inflated from an uninflated state to
an inflated state.
2. The delivery apparatus of claim 1, wherein the distal end
portion of the second shaft comprises a plurality of longitudinally
extending slots defining a plurality of circumferentially spaced
deflectable sections that can deflect radially outwardly from one
another when the balloon is inflated.
3. The delivery apparatus of claim 2, wherein the plurality of
deflectable sections comprise a plurality of metal sections.
4. The delivery apparatus of claim 3, wherein the distal end
portion of the second shaft further comprises a further material
layer overlaying each metal section.
5. The delivery apparatus of claim 4, wherein the further material
layer is overmolded onto the metal sections.
6. The delivery apparatus of claim 2, wherein the slots intersect a
terminal distal end of the distal end portion the second shaft.
7. The delivery apparatus of claim 1, further comprising a nose
piece disposed on the distal end portion of the first shaft at a
location distal to the balloon, wherein a proximal end portion of
the nose piece is configured to deflect radially outward when the
balloon is inflated from an uninflated state to an inflated
state.
8. The delivery apparatus of claim 7, wherein the nose piece
comprises a plurality of slots defining a plurality of deflectable
nose piece segments.
9. An assembly, comprising: a delivery apparatus comprising a
handle, a first shaft extending distally from the handle, the first
shaft having a distal end portion, an inflatable balloon mounted on
the distal end portion of the first shaft, a second shaft extending
distally from the handle at least partially over the first shaft,
the second shaft having a distal end portion comprising a plurality
of longitudinally extending fingers spaced apart from one another
in a circumferential direction by a plurality of longitudinally
extending slots; and a prosthetic heart valve that is radially
expandable and compressible between a radially compressed
configuration and a radially expanded configuration, wherein the
prosthetic heart valve is mounted on the balloon in the radially
compressed configuration; wherein the distal end portion of the
second shaft extends at least partially over the balloon such that
as the balloon is inflated from an uninflated state to an inflated
state to expand the prosthetic heart valve, the fingers deflect
radially outward.
10. The assembly of claim 9, wherein the slots extend
longitudinally along the distal end portion of the second shaft and
intersect a terminal distal end of the second shaft.
11. The assembly of claim 9, wherein the fingers have distal ends
that abut an adjacent end of the prosthetic heart valve.
12. The assembly of claim 9, further comprising an introducer
sheath and wherein the fingers can deflect radially inward when
inserted through the introducer sheath.
13. The assembly of claim 9, further comprising a nose cone
including a plurality of nose cone fingers spaced apart from one
another by a plurality of slots, the plurality of nose cone fingers
configured to deflect radially outward when the balloon is inflated
from the uninflated state to the inflated state.
14. The assembly of claim 9, wherein the fingers flare from a first
outer diameter at proximal ends of the fingers to a second, lager,
diameter at distal ends of the fingers when the balloon is in the
uninflated state.
15. The assembly of claim 9, wherein the distal end portion of the
second shaft has a first outer diameter proximal to the fingers and
a second outer diameter at distal ends of the fingers, wherein the
second outer diameter is greater than the first outer diameter when
the balloon is in the uninflated state.
16. A method, comprising: inserting a distal end portion of a
delivery apparatus and a prosthetic heart valve into a patient's
vasculature, the delivery apparatus comprising a first shaft; an
inflatable balloon mounted on a distal end portion of the first
shaft; and a second shaft extending coaxially over at least a
portion of the first shaft and having a distal end portion
comprising a plurality of fingers spaced apart from one another by
a plurality of slots, wherein the prosthetic heart valve is mounted
on the balloon in a crimped configuration; advancing the distal end
portion of the delivery apparatus and the prosthetic heart valve
through the vasculature of the patient to a selected implantation
site; and inflating the balloon to radially the prosthetic heart
valve from the crimped configuration to a radially expanded
configuration, wherein inflating the balloon causes the plurality
of fingers of the distal end portion of the second shaft to deflect
radially outward from each other.
17. The method of claim 16, wherein during advancing the distal end
portion of the delivery apparatus and the prosthetic heart valve
through the vasculature of the patient, the plurality of fingers
abut an adjacent end of the prosthetic valve.
18. The method of claim 16, wherein inserting the distal end
portion of the delivery apparatus and the prosthetic heart valve
into the patient's vasculature comprises inserting the distal end
portion of the delivery apparatus and the prosthetic heart valve
through an introducer sheath, which causes the plurality of fingers
of the distal end portion of the second shaft to deflect radially
inward.
19. The method of claim 16, wherein during advancing the distal end
portion of the delivery apparatus and the prosthetic heart valve
through the vasculature of the patient, the plurality of fingers of
the distal end portion of the second shaft extend over a portion of
the balloon.
20. The method of claim 16, wherein the slots intersect a terminal
distal end of the second shaft.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 16/197,244, filed Nov. 20, 2018, which is a
continuation of U.S. patent application Ser. No. 14/736,117, filed
Jun. 10, 2015, which is a continuation of U.S. patent application
Ser. No. 12/247,846, filed Oct. 8, 2008, now U.S. Pat. No.
9,061,119, which claims the benefit of U.S. Provisional Application
Nos. 61/083,117, filed Jul. 23, 2008, and 61/052,009, filed May 9,
2008. Each related application is incorporated by reference
herein.
FIELD
[0002] The present invention relates to implantable devices. More
particularly, the present invention relates to devices and methods
for implantation of a prosthetic heart valve.
BACKGROUND
[0003] A transcatheter heart valve (THV) is a prosthetic heart
valve which is configured to be implanted by a catheterization
technique. One type of THV has been developed by Edwards
Lifesciences of Irvine, Calif. and is described in U.S. Pat. No.
6,730,118, which is herein incorporated by reference in its
entirety. The THV described in the '118 patent is primarily
configured for replacing the function of a stenotic aortic valve in
a human heart. An important feature of the THV is the ability to be
implanted within the stenotic region of the native aortic valve.
After implantation, the THV holds open the leaflets of the native
aortic valve open and utilizes the native valve annulus as an
attachment means for the THV.
[0004] An important design parameter of the THV is the diameter of
the folded or crimped profile. The diameter of the crimped profile
is important because it directly influences the physician's ability
to advance the THV through the femoral artery or vein. More
particularly, a smaller profile allows for treatment of a wider
population of patients, with enhanced safety.
SUMMARY
[0005] Traditionally, the THV is crimped directly onto a balloon of
a balloon catheter and the crimped THV and balloon are navigated
through the patient's vasculature to the implantation site. Because
of the thickness of the balloon material, the valve cannot be
crimped to its smaller possible profile. In certain embodiments
disclosed below, the balloon is positioned either distal or
proximal to the crimped THV. This allows the THV to be crimped to a
smaller diameter. After the THV is advanced through narrow portions
in a patient's vasculature (for example, the iliac artery which is
typically the narrowest portion of the relevant vasculature), the
THV is placed onto the balloon. If the THV has not yet been
advanced to the treatment site when the balloon member is
repositioned underneath the THV, then the THV can then be advanced
further to the treatment site and the balloon can be inflated to
radially expand the THV within the native heart valve.
[0006] Advantageously, certain embodiments allow the THV to be
crimped to a much smaller diameter and thereby overcome the primary
shortcoming associated with THV deployment.
[0007] In one embodiment, an apparatus for delivering a prosthetic
valve through the vasculature of a patient is disclosed. The
apparatus comprises a main catheter, a balloon catheter, and a
valve carrying member. The main catheter comprises an elongated
shaft. The balloon catheter comprises an elongated shaft and a
balloon connected to a distal end portion of the shaft. The shaft
of the balloon catheter is capable of moving longitudinally within
the shaft of the main catheter. The valve carrying member has a
mounting surface for receiving a crimped valve for insertion into
the vasculature of the patient. The balloon is positioned distal or
proximal to the mounting surface and the balloon is configured to
be movable relative to the mounting surface, or vice versa, to
position the balloon at a location extending through the crimped
valve after the valve is inserted into the patient's
vasculature.
[0008] In specific implementations, the apparatus further comprises
a nose piece and the valve carrying member extends between a
proximal end of the nose piece and a distal end of the shaft of the
main catheter.
[0009] In specific implementations, the valve carrying member
comprises two or more strip members, with the strip members
attached to the proximal end of the nose piece and the distal end
of the shaft of the main catheter. In other specific
implementations, the strip members are formed of a polymer
material. In other specific implementations, the strip members are
attached to an inside surface of the nose piece and an inside
surface of the distal end of the shaft of the main catheter. In
other specific implementations, the strip members comprise four
polymer strips.
[0010] In specific implementations, a proximal end of the nose
piece comprises one or more slits and the distal end of the shaft
of the main catheter comprises one or more slits. In other specific
implementations, the distal end of the shaft of the main catheter
further comprises a flex adapter disposed at the location of the
slits, with the flex adaptor having two or more fingers that are
configured to maintain the slits in a radially expanded position in
the absence of an inwardly directed force.
[0011] In specific implementations, the nose piece further
comprises a polymer jacket surrounding at least a portion of the
slits on the nose piece. In other specific implementations, the one
or more strip members are positioned between the slits on the
proximal end of the nose piece and the distal end of the shaft of
the main catheter.
[0012] In specific implementations, the valve carrying member
comprises an elongated shaft that extends coaxially with respect to
the shaft of the main catheter. In other specific implementations,
the shaft of the valve carrying member has a distal end portion
that extends beyond the distal end of the shaft of the main
catheter. The distal end portion of the shaft of the valve carrying
member can comprise the mounting surface of the valve carrying
member.
[0013] In specific implementations, the prosthetic valve is
connected to the distal end of the shaft of the main catheter using
a temporary connecting device. In other specific implementations,
the temporary connecting device can comprise suture connected to
the valve and a wire that is connected to the shaft of the main
catheter and the suture. In other specific implementations, the
shaft of the valve carrying member comprises a Nitinol braid or a
polymer braid.
[0014] In specific implementations, the apparatus further comprises
a nose piece, and the shaft of the valve carrying member extends
between a proximal end of the nose piece and a distal end of the
shaft of the main catheter. In other specific implementations, the
distal end of the shaft of the valve carrying member is attached to
an inside surface of the nose piece, and a portion of the shaft of
the valve carrying member is disposed within the shaft of the main
catheter.
[0015] In another embodiment, an apparatus for delivering a
prosthetic valve through the vasculature of a patient is disclosed.
The apparatus comprises a main catheter and a balloon catheter. The
main catheter comprises an elongated shaft. The balloon catheter
comprises an elongated shaft, a balloon connected to a distal end
portion of the shaft, and an extension portion. The balloon
catheter is capable of moving longitudinally within the shaft of
the main catheter. The extension portion of the balloon catheter is
located between the balloon and the elongated shaft and is
configured to receive a prosthetic valve in a crimped state on an
outer surface of the extension portion.
[0016] In specific implementations, the extension portion of the
balloon catheter is formed of the same material as the balloon. In
other specific implementations, the apparatus further comprises a
nose piece with a distal portion of the balloon is attached to the
nose piece. The distal portion of the balloon can be attached at
approximately the mid-point of the nose piece.
[0017] In addition, the nose piece can be configured to move
relative to the crimped prosthetic valve, so that the nose piece
can be moved adjacent to the crimped prosthetic valve while the
crimped prosthetic valve is in the vasculature of the patient. The
nose piece can have a substantially hourglass shape with a proximal
concave portion, wherein the proximal concave portion of the nose
piece is configured to receive at least a portion of the balloon
when the nosepiece is moved adjacent to the crimped prosthetic
valve.
[0018] In other specific implementations, the apparatus further
comprises an expansion member that is disposed beneath the
extension portion of the balloon catheter. The balloon and the
expansion member are both configured to expand to a respective
maximum expansion diameter, with the maximum expansion diameter of
the balloon being greater than that of the expansion member. In
other specific implementations, a dilator is disposed at a distal
end of the extension portion, the dilator being configured to
partially expand the crimped valve when the dilator is moved
relative to the crimped valve. In other specific implementations, a
stopper is disposed at a proximal end of the extension portion, the
stopper being configured to resist movement of the crimped valve on
the extension portion.
[0019] In another embodiment, a method of implanting a prosthetic
valve at an implantation site in a patient's body is disclosed. The
method comprises providing a delivery apparatus that comprises a
main catheter that has an elongated shaft, a balloon catheter that
has an elongated shaft and a balloon connected to a distal end
portion of the shaft, and a valve carrying member. The valve is
crimped to a smaller profile on a mounting surface of the valve
carrying member. The valve and the delivery apparatus are inserted
into the vasculature of the patient's body via an introducer
sheath. The valve is mounted on the balloon after the valve passes
through the introducer sheath. The valve is deployed at the
implantation site by expanding the balloon.
[0020] In specific implementations, the method further comprises
advancing the valve to the implantation site, wherein the act of
mounting the valve on the balloon occurs after the valve passes
through the introducer sheath but before advancing the valve to the
implantation site.
[0021] In specific embodiments, the balloon is positioned proximal
to the mounting surface during the act of crimping the valve, and
the act of mounting the valve on the balloon comprises moving the
balloon distally so that balloon is positioned underneath the
crimped valve. In other specific implementations, the balloon is
positioned distal to the mounting surface during the act of
crimping the valve, and the act of mounting the valve on the
balloon comprises moving the balloon proximally so that balloon is
positioned underneath the crimped valve.
[0022] In specific implementations, the delivery apparatus further
comprises a nose piece and the valve carrying member extends
between a proximal end of the nose piece and a distal end of the
shaft of the main catheter. In other specific implementations, the
method further comprises securing the prosthetic valve to a distal
end of the shaft of the main catheter using a temporary connection
device. In other specific implementations, the method further
comprises releasing the valve from the main catheter shaft after
mounting the valve on the balloon.
[0023] In another embodiment, a method of implanting a prosthetic
valve at an implantation site in a patient's body is disclosed. The
method comprises: (a) providing a delivery apparatus that comprises
a main catheter that has an elongated shaft, and a balloon catheter
that has an elongated shaft, a valve carrying member, and a balloon
connected to a distal end portion of the shaft, the valve carrying
member of the balloon catheter being located between the balloon
and the elongated shaft; (b) crimping the valve to a smaller
profile on a mounting surface of the valve carrying member; (c)
maneuvering the crimped valve through an introducer sheath into the
vasculature of the patient's body; (d) adjusting the balloon's
position relative to the crimped valve so that the balloon is
positioned underneath the crimped valve; and (e) deploying the
valve at the implantation site by expanding the balloon.
[0024] In specific implementations, the method further comprises
partially expanding the valve by expanding an expansion member
prior to adjusting the balloon's position relative to the
valve.
[0025] In another embodiment, a method of implanting a prosthetic
valve at an implantation site in a patient's body is disclosed. The
method comprises: placing the valve in a crimped state on a distal
end portion of an elongated delivery apparatus; inserting the
crimped valve into the patient's body; subsequent to the act of
inserting the crimped valve into the patient's body, moving the
crimped valve onto an inflatable balloon on the distal end portion
of the delivery apparatus; and deploying the valve at the
implantation site by inflating the balloon.
[0026] In another embodiment, an apparatus for advancing a catheter
through to an introducer sheath is disclosed. The apparatus
comprises a retaining member and a drive member. The retaining
member is configured to hold the introducer sheath in place
relative to the apparatus. The drive member is operable to engage
and drive the catheter through the introducer sheath.
[0027] In specific implementations, the drive member comprises a
rotatable member and a first gear member. The first gear member
comprises an engagement surface that is configured to frictionally
engage an outside surface of the catheter. Rotating the rotatable
member causes the first gear member to rotate and drive the
catheter in a longitudinal direction relative to the introducer
sheath.
[0028] In other specific implementations, the apparatus further
comprises a second gear member. The second gear member also has an
engagement surface that is configured to frictionally engage the
outside surface of the catheter. In other specific implementations,
both the first and second gear members have teeth, and when the
first gear member rotates, the teeth of the first gear member
engage the teeth of the second gear member so that the second gear
member also rotates and drives the catheter in the longitudinal
direction relative to the introducer sheath.
[0029] In other specific implementations, at least a portion of the
engagement surface of the first gear member is coated with an
elastomeric material. In other specific implementations, the first
gear member comprises two parallel o-ring members.
[0030] In another embodiment, a method of advancing a catheter
through an introducer sheath is disclosed. The method comprises
providing an advancement apparatus having a drive member and a
retaining member. The retaining member is configured to hold the
introducer sheath in place relative to the advancement apparatus.
The method further comprises securing the retaining member to the
introducer sheath; and manually driving the drive member so that
the drive member engages and drives the catheter through the
introducer sheath.
[0031] In specific implementations, the drive member comprises a
rotatable member and a first gear member, the first gear member
comprising an engagement surface that is configured to frictionally
engage an outside surface of the catheter, and the act of manually
driving the drive member comprises rotating the rotatable member to
cause the first gear member to rotate and drive the catheter in a
longitudinal direction relative to the introducer sheath.
[0032] In another embodiment, an apparatus for indicating flex of a
distal end of a catheter is disclosed. The apparatus comprises an
elongated shaft; at least one wire connected to a distal end
portion of the elongated shaft; a handle portion comprising a flex
activating member, the flex activating member being coupled to the
at least one wire such that adjustment of the flex activating
member causes the distal end portion of the shaft to flex; and a
flex indicating member. Adjustment of the flex activating member
causes the flex indicating member to move relative to the handle to
indicate an amount of flex of the distal end portion of the
shaft.
[0033] In specific implementations, the flex activating member
comprises a rotatable member. In other specific implementations,
the handle portion comprises a slot for receiving at least a
portion of the flex indicating member. In other specific
implementations, the rotatable member includes an internally
threaded surface portion and an externally threaded surface
portion. The internally threaded surface portion is configured to
receiving a slide member connected to the at least one wire, and
the externally threaded surface portion is configured to receive an
extending portion of the flex indicating member. In other specific
implementations, rotating the rotatable member causes the slide
member to move along the internally threaded surface portion and
the movement of the slide member along the internally threaded
surface portion changes the amount of flex of the distal end
portion of the shaft. The rotation of the rotatable member causes
the flex indicating member to move longitudinally and change its
position within the slot of the handle portion and the position of
the flex indicating member within the slot indicates the amount of
flex of the distal end portion of the shaft.
[0034] In another embodiment, a method for manipulating a delivery
apparatus through the vasculature of a patient is disclosed. The
method comprises providing a delivery apparatus having an elongated
shaft, a flex indicating member, and a handle portion, the handle
portion comprising a flex activating member. The method further
comprises manipulating the flex activating member to cause a distal
end portion of the shaft to flex and to cause the flex indicating
member to move relative to the handle portion. The method further
comprises determining an amount of flex of the distal end portion
of the shaft by observing a position of the flex indicating member
relative to the handle portion.
[0035] In another embodiment, an apparatus for delivering a
prosthetic valve through the vasculature of a patient can comprise
a main catheter, a balloon catheter and a nose piece. The main
catheter can comprise an elongated shaft. The balloon catheter can
comprise an elongated shaft and a balloon connected to a distal end
portion of the shaft. The shaft of the balloon catheter can be
capable of moving longitudinally within the shaft of the main
catheter. The nose piece can be disposed at a distal end of the
main catheter and can comprise a balloon.
[0036] In another embodiment, an apparatus can include a main
catheter comprising an elongated shaft, a balloon catheter
comprising an elongated shaft and a balloon connected to a distal
end portion of the shaft, and an adjustment device. The shaft of
the balloon catheter can be capable of moving longitudinally within
the shaft of the main catheter. The adjustment device can have a
first portion and a second portion, the first and second portions
being coupled together and being configured to rotate relative to
each other to move from a first configuration to a second
configuration. The relative longitudinal positions of the first and
second portions in the first configuration can be different from
the relative longitudinal positions of the first and second portion
in the second configuration. The first portion can be coupled to
the elongated shaft of the main catheter to restrict movement of
the elongated shaft of the main catheter relative to the first
portion, and the second portion can be coupled to the elongated
shaft of the balloon catheter to restrict movement of the elongated
shaft of the balloon catheter relative to the second portion, such
that movement of the first and second portions between the first
and second configurations is effective to move the shafts relative
to each other.
[0037] In specific implementations, the first and second portions
are further apart from each other in the second configuration than
in the first configuration. In other implementations, the second
portion further comprises a securing mechanism, the securing
mechanism being configured to releasably secure the elongated shaft
of the balloon catheter to the second portion. In other
implementations, the elongated shaft of the balloon catheter has at
least one grooved section, the securing mechanism being biased to
engage the grooved section to restrict movement of the elongated
shaft of the balloon catheter relative to the second portion. In
other specific implementations, the securing mechanism comprises an
opening and a portion defining the opening, and the securing
mechanism is disposed in the second portion so that the elongated
shaft of the balloon catheter passes through the opening and the
portion defining the opening is configured to engage with the
grooved section.
[0038] In other specific implementations, each of the first and
second portions has a threaded section, the threaded sections being
configured to couple the first portion and second portion together.
In other specific implementations, the adjustment device further
comprises a rotatable member, the rotatable member being rotatable
to move the first portion and the second portion from the first
configuration to the second configuration. In other
implementations, the apparatus further comprises a stop member, the
stop member being configured to prevent the first and second
portions from being separated from one another.
[0039] In another embodiment, a method for adjusting the relative
positions of elongated shafts in a delivery apparatus is disclosed.
The method comprising providing a delivery apparatus having an
elongated shaft of a main catheter and an elongated shaft of a
balloon catheter, the elongated shaft of the balloon catheter being
at least partially disposed within the elongated shaft of the main
catheter. An adjustment apparatus is provided, the adjustment
apparatus having a first portion coupled to a second portion, the
first and second portions being rotatable relative to each other.
The elongated shaft of the main catheter is secured to the first
portion. The elongated shaft of the balloon catheter is secured to
the second portion. The first and second portions are rotated
relative to each other, the rotation being effective to change the
position of the second portion relative to the first portion such
that the relative positions of the elongated shafts of the balloon
catheter and the main catheter are adjusted.
[0040] In specific implementations, the balloon catheter comprises
a balloon disposed at the distal end of the elongated shaft of the
balloon catheter, and the delivery apparatus further comprises a
valve disposed at a distal end of the delivery apparatus, and
wherein the act of rotating the first and second portions relative
to each other is effective to mount the valve on the balloon.
[0041] In specific implementations, the first and second portions
comprise threaded portions that couple the first and second
portions together, and the act of rotating the first and second
portions relative to each other comprises rotating one or both of
the first and second portions about the threaded portions.
[0042] The foregoing and other objects, features, and advantages of
the invention will become more apparent from the following detailed
description, which proceeds with reference to the accompanying
figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0043] FIG. 1 is side view of an endovascular delivery apparatus
for implanting a prosthetic valve.
[0044] FIG. 2A is side view of the balloon catheter of the delivery
apparatus of FIG. 1, shown partially in section.
[0045] FIG. 2B is an enlarged, cross-sectional view of the balloon
catheter shown in FIG. 2A.
[0046] FIG. 3 is a side view of an endovascular delivery apparatus
for implanting a prosthetic valve, shown partially in section.
[0047] FIG. 4 is a side view of an endovascular delivery apparatus
for implanting a prosthetic valve, shown partially in section.
[0048] FIG. 5 is a side view of an endovascular delivery apparatus
for implanting a prosthetic valve, shown partially in section.
[0049] FIG. 6 is a perspective view of a nose piece for use with an
endovascular delivery apparatus for implanting a prosthetic
valve.
[0050] FIG. 7 is a perspective view of a nose piece for use with an
endovascular delivery apparatus for implanting a prosthetic
valve.
[0051] FIG. 8 is a side view of an endovascular delivery apparatus
for implanting a prosthetic valve, shown partially in section.
[0052] FIG. 9 is a side view of an endovascular delivery apparatus
for implanting a prosthetic valve, shown partially in section.
[0053] FIG. 10 is a side view of an endovascular delivery apparatus
for implanting a prosthetic valve, shown partially in section.
[0054] FIG. 11 is a side view of an endovascular delivery apparatus
for implanting a prosthetic valve, shown partially in section.
[0055] FIG. 12 is a side view of an endovascular delivery apparatus
for implanting a prosthetic valve, shown partially in section.
[0056] FIG. 13 is a side view of an endovascular delivery apparatus
for implanting a prosthetic valve, shown partially in section.
[0057] FIG. 14 is a side view of an endovascular delivery apparatus
for implanting a prosthetic valve, shown partially in section.
[0058] FIG. 15 is a side cross section view of an endovascular
delivery apparatus for implanting a prosthetic valve.
[0059] FIG. 16 is a side cross section view of an endovascular
delivery apparatus for implanting a prosthetic valve.
[0060] FIG. 17 is a side cross section view of an endovascular
delivery apparatus for implanting a prosthetic valve.
[0061] FIG. 18 is a side cross section view of an endovascular
delivery apparatus for implanting a prosthetic valve.
[0062] FIG. 19 is a side cross section view of an endovascular
delivery apparatus for implanting a prosthetic valve.
[0063] FIG. 20 is a side cross section view of an endovascular
delivery apparatus for implanting a prosthetic valve.
[0064] FIG. 21A is a perspective view of a dilator for use with an
endovascular delivery apparatus for implanting a prosthetic
valve.
[0065] FIG. 21B is bottom view of a dilator for use with an
endovascular delivery apparatus for implanting a prosthetic
valve.
[0066] FIG. 21C is a cross section view of a dilator for use with
an endovascular delivery apparatus for implanting a prosthetic
valve, taken along line 21C-21C.
[0067] FIG. 22A is a perspective view of a flex tip for use with an
endovascular delivery apparatus for implanting a prosthetic
valve.
[0068] FIG. 22B is a side view of a flex tip for use with an
endovascular delivery apparatus for implanting a prosthetic
valve.
[0069] FIG. 22C is a top view of a flex tip for use with an
endovascular delivery apparatus for implanting a prosthetic
valve.
[0070] FIG. 22D is another side view of a flex tip for use with an
endovascular delivery apparatus for implanting a prosthetic
valve.
[0071] FIG. 23A is a perspective view of a flex tip attached to a
distal end of a catheter for use with an endovascular delivery
apparatus for implanting a prosthetic valve.
[0072] FIG. 23B is a cross section view of a flex tip attached to a
distal end of a catheter for use with an endovascular delivery
apparatus for implanting a prosthetic valve.
[0073] FIG. 24 is a side view of an endovascular delivery apparatus
for implanting a prosthetic valve, shown partially in section.
[0074] FIG. 25 is a side view of an embodiment of a catheter
advancement device, shown in a partially open position.
[0075] FIG. 26 is a side view of the catheter advancement device of
FIG. 25.
[0076] FIG. 27 is an exploded perspective view of the catheter
advancement device of FIG. 25.
[0077] FIG. 28 is a perspective view of a gear member for use with
a catheter advancement device.
[0078] FIG. 29 is an end view of another gear member for use with a
catheter advancement device.
[0079] FIG. 30 is a partial perspective view of an embodiment of an
advancement device, with certain elements removed for clarity.
[0080] FIG. 31 is a side view of an embodiment of a flex indicating
device for use in deploying a catheter into a patient's
vasculature.
[0081] FIG. 32 is a perspective view of a flex activating member
for use with the flex indicating device shown in FIG. 31.
[0082] FIG. 33 is a partial perspective view of the flex indicating
device shown in FIG. 31.
[0083] FIG. 34 is a perspective view of an indicator pin for use
with the flex indicating device shown in FIG. 31.
[0084] FIG. 35A is a partial perspective view of a flex indicating
device.
[0085] FIG. 35B is a partial perspective view of a flex indicating
device.
[0086] FIG. 36 is a partial cross section view of a handle portion
of a flex indicating device with an elongated shaft that has a
steerable section at a distal end.
[0087] FIG. 37 is a partial perspective cross section view of a
flex indicating device.
[0088] FIG. 38A is a top perspective view of an indicator pin for
use with the flex indicating device shown in FIG. 31.
[0089] FIG. 38B is a bottom perspective view of an indicator pin
for use with the flex indicating device shown in FIG. 31.
[0090] FIG. 39A is a side view of an endovascular delivery
apparatus for implanting a prosthetic valve, shown partially in
section.
[0091] FIG. 39B is a side view of an endovascular delivery
apparatus for implanting a prosthetic valve, shown partially in
section.
[0092] FIG. 39C is a side view of an endovascular delivery
apparatus for implanting a prosthetic valve, shown partially in
section.
[0093] FIG. 40 is a perspective view of an adjustment device for
adjusting the relative positions of elongated catheter shafts.
[0094] FIG. 41 is a securing mechanism for use with the adjustment
device of FIG. 40.
[0095] FIG. 42 is a cross section view of the adjustment device of
FIG. 40.
[0096] FIG. 43A is a partial cross section view of the adjustment
device of FIG. 40, shown with a securing mechanism in an unsecured
position.
[0097] FIG. 43B is a partial cross section view of the adjustment
device of FIG. 40, shown with a securing mechanism in a secured
position.
[0098] FIG. 43C is a partial cross section view of the adjustment
device of FIG. 40, shown with a securing mechanism locked in an
unsecured position.
DETAILED DESCRIPTION
[0099] As used in this application and in the claims, the singular
forms "a," "an," and "the" include the plural forms unless the
context clearly dictates otherwise. Additionally, the term
"includes" means "comprises." Further, the terms "coupled"
generally means electrically, electromagnetically, and/or
physically (e.g., mechanically or chemically) coupled or linked and
does not exclude the presence of intermediate elements between the
coupled items.
[0100] FIG. 1 shows a delivery apparatus 10 adapted to deliver a
prosthetic heart valve 12 (e.g., a prosthetic aortic valve) to a
heart, according to one embodiment. The apparatus 10 generally
includes a steerable guide catheter 14, and a balloon catheter 16
extending through the main catheter 14. The guide catheter can also
be referred to as a flex catheter or a main catheter. The use of
the term main catheter should be understood, however, to include
flex or guide catheters, as well as other catheters that do not
have the ability to flex or guide through a patient's
vasculature.
[0101] The guide catheter 14 and the balloon catheter 16 in the
illustrated embodiment are adapted to slide longitudinally relative
to each other to facilitate delivery and positioning of valve 12 at
an implantation site in a patient's body, as described in detail
below.
[0102] The guide catheter 14 includes a handle portion 20 and an
elongated guide tube, or shaft, 22 extending from handle portion
20. Balloon catheter 16 includes a proximal portion 24 adjacent
handle portion 20 and an elongated shaft 26 that extends from
proximal portion 24 and through handle portion 20 and guide tube
22. The handle portion 20 can include a side arm 27 having an
internal passage which fluidly communicates with a lumen defined by
the handle portion 20. An inflatable balloon 28 is mounted at the
distal end of balloon catheter 16. In FIG. 1, valve 12 is
positioned distally to balloon 28 (not shown in FIG. 1) and is
shown in a crimped state, providing valve 12 with a reduced
diameter for delivery to the heart via the patient's vasculature.
Because valve 12 is crimped at a location different from the
location of balloon 28 (e.g., in this embodiment valve 12 is
crimped distal to balloon 28), valve 12 can be crimped to a lower
profile than would be possible if valve 12 was crimped on top of
balloon 28. This lower profile permits the surgeon to more easily
navigate the delivery apparatus (including crimped valve 12)
through a patient's vasculature to the treatment location. The
lower profile of the crimped valve is particularly helpful when
navigating through portions of the patient's vasculature which are
particularly narrow, such as the iliac artery.
[0103] A nose piece 32 can be mounted at the distal end of the
delivery apparatus 10 to facilitate advancement of the delivery
apparatus 10 through the patient's vasculature to the implantation
site. In some instances, it may be useful to have nose piece 32
connected to a separate elongated shaft so that nose piece 32 can
move independently of other elements of delivery apparatus 10.
[0104] Nose piece 32 can be formed of a variety of materials,
including various plastic materials. Alternatively, nose piece 32
can comprise an inflatable balloon member. When inflated, nose
piece 32 can generally form a cone shape, such as is shown in FIG.
1. The inflation of nose piece 32, when nose piece 32 comprises a
balloon member, can be achieved by having a lumen extend from a
proximal end of the delivery apparatus to nose piece 32. A fluid
pressurizing device can be in fluid contact with the lumen, and
nose piece 32 can be inflated and deflated by the fluid
pressurizing device. Nose piece 32 can be inflated to help track
nose piece 32 through the vasculature of a patient and/or to
provide a surface against which valve 12 can abut, which can help
maintain the position of valve 12 on the delivery apparatus until
deployment at the treatment site. For example, referring to FIG. 24
(discussed in more detail below), a balloon nose piece could be
positioned distal to valve 12 and the balloon nose piece can be
used to track the delivery system through a patient's vasculature.
After deployment of valve 12 at the treatment site, nose piece 32
can be deflated, thereby reducing the profile of the delivery
apparatus for withdrawal from the patient's vasculature.
[0105] As can be seen in FIGS. 2A and 2B, balloon catheter 16 in
the illustrated configuration further includes an inner shaft 34
(FIG. 2B) that extends from proximal portion 24 and coaxially
through outer shaft 26 and balloon 28. Balloon 28 can be supported
on a distal end portion of inner shaft 34 that extends outwardly
from outer shaft 26 with a proximal end portion 36 of the balloon
secured to the distal end of outer shaft 26 (e.g., with a suitable
adhesive). The outer diameter of inner shaft 34 is sized such that
an annular space is defined between the inner and outer shafts
along the entire length of the outer shaft. Proximal portion 24 of
the balloon catheter can be formed with a fluid passageway 38 that
is fluidly connectable to a fluid source (e.g., a water source) for
inflating the balloon. Fluid passageway 38 is in fluid
communication with the annular space between inner shaft 34 and
outer shaft 26 such that fluid from the fluid source can flow
through fluid passageway 38, through the space between the shafts,
and into balloon 28 to inflate the same and deploy valve 12.
[0106] Proximal portion 24 also defines an inner lumen 40 that is
in communication with a lumen 42 of inner shaft 34. The lumens 40,
42 in the illustrated embodiment can be sized to receive the shaft
of a nose catheter, if desired. Balloon catheter 16 also can
include a coupler 44 connected to proximal portion 24 and a tube 46
extending from the coupler. Tube 46 defines an internal passage
which fluidly communicates with lumen 40. Balloon catheter 16 also
can include a slide support 48 connected to the proximal end of
coupler 44. The slide support 48 can support and cooperate with an
adjustment ring 50 of a catheter (such as a nose catheter) to allow
the catheter to be maintained at selected longitudinal positions
relative to balloon catheter 16.
[0107] Inner shaft 34 and outer shaft 26 of the balloon catheter
can be formed from any of various suitable materials, such as
nylon, braided stainless steel wires, or a polyether block amide
(commercially available as Pebax.RTM.). Shafts 26, 34 can have
longitudinal sections formed from different materials in order to
vary the flexibility of the shafts along their lengths. Inner shaft
34 can have an inner liner or layer formed of Teflon.RTM. to
minimize sliding fricktion with nose catheter shaft 30.
[0108] FIGS. 3-5 illustrate an embodiment in which balloon 28 of
balloon catheter 16 is initially positioned proximal to valve 12.
FIG. 3 shows a delivery apparatus with support members 58 that are
attached to nose piece 32 and a distal end of guide catheter 14. As
discussed in more detail below, in this embodiment support members
58 (or valve carrying member) can take the form of polymer strips.
For clarity, FIG. 3 shows the delivery apparatus without valve 12.
FIG. 4 shows the delivery apparatus with valve 12 crimped on
support members 58. FIG. 5 shows the delivery apparatus with valve
12 being expanded by balloon 28. In FIGS. 4 and 5, valve 12 is
shown in section view so that the elements beneath valve 12 can be
more easily understood.
[0109] Nose piece 32 in this embodiment is desirably a split nose
piece having one or more slits 54 to accommodate expansion of
balloon 28. Similarly, the distal end of guide catheter 14 is
desirably formed with one or more slits 56 to accommodate expansion
of balloon 28. The number of slits 54, 56 on the delivery apparatus
10 can vary. The nose piece 32 and the distal end of the guide
catheter 14 desirably have about 1-8 slits each. In the present
example, both the nose piece 32 and the distal end of the guide
catheter 14 have four slits.
[0110] Support members 58 are attached to the proximal end of the
nose piece 32 and the distal end of the guide catheter 14. Like the
number of slits, the number of support members 58 can also vary. In
the present example, there are four support members 58, with each
support member (or strip) attaching to the nose piece 32 and the
distal end of the guide catheter 14 between adjacent slits 54, 56.
By having the same number of support members as there are slits in
the nose piece and guide catheter, the support members 58 can be
positioned intermediate the locations of the slits 54, 56.
[0111] In addition, if the number of slits and support members is
the same, the slits and strips can be formed in a single cutting
step. For example, an uncut cylindrical element can initially be
attached to an uncut nose piece 32 and an uncut guide catheter 14.
After attaching the cylindrical element to the nose piece 32 and
the guide catheter 14, cuts can be made in each of the nose piece
32, guide catheter 14, and the cylindrical element (forming support
members, or polymer strips, 58). In this manner, the cylindrical
element can be cut into strips at the same time the slits in the
nose piece and guide catheter are formed. In addition, by cutting
the strips and slits in the same action, support members 58 will
naturally align between slits 54, 56.
[0112] Alternatively, slits 54, 56 can be formed in nose piece 32
and guide catheter 14 before the strips are secured to the nose
piece and guide catheter. Also, in another embodiment, the support
members can be laser scored rather than formed into strips. Upon
application of radial pressure (e.g., balloon expansion pressures),
the laser-scored support member will break apart, thereby
permitting expansion of the support member.
[0113] There need not be a one-to-one correspondence of support
members 58 to slits 54, 56. Instead, if desired, there can be more
support members 58 than slits 54, 56, or, alternatively, more slits
54, 56 than support members 58. Depending on the type of materials
selected for the support members (or strips), it may be desirable
to vary the form and shape of the support members. For example, it
may be desirable to have more support members, fewer support
members, smaller spaces (or gaps) between the support members, or
wider spaces (or gaps) between the support members.
[0114] Support members 58 can be formed of a variety of materials.
For example, support members 58 can be formed of such polymers as
nylon, PET, PEEK, PE, Pebax, Urethane, and PVC. Support members 58
can be formed of a material that is non-compliant. Alternatively,
support members 58 can be formed of materials that are flexible
and/or stretchable so that when the balloon 28 is inflated, the
support members can flex and/or stretch with the expansion of the
balloon 28.
[0115] Support members 58 can be attached to inside or outside
portions of nose piece 32 and the distal end of guide catheter 14.
Support members 58, however, are desirably attached inside of nose
piece 32 and guide catheter 14. In this manner, when valve 12 is
crimped on support members 58, the proximal edge of nose piece 32
and the distal edge of guide catheter 14 can abut the opposite ends
of the valve and form a natural barrier, thereby reducing the
likelihood that valve 12 will slide longitudinally or move out of
position between nose piece 32 and guide catheter 14. If support
members 58 are attached on an outside portion of nose piece 32 and
guide catheter 14, valve 12 will not be held in position by the
ends of the nose piece and guide catheter. Accordingly, if support
members 58 are attached to the outside portion of these elements,
it may be desirable to further include a stopping mechanism (such
as a raised portion or lip) at the area just outside of the
location where the valve will seat on the support members to reduce
the risk that valve 12 will slide out of position over the adjacent
edges of nose piece 32 and guide catheter 14.
[0116] FIG. 4 shows valve 12 crimped on support members 58, with
balloon 28 positioned proximally to valve 12. As discussed above,
since balloon 28 is not positioned inside valve 12, valve 12 can be
crimped to a smaller profile. Thus, the delivery apparatus can more
easily navigate the narrowest portions of the patient's
vasculature. After valve 12 advances through the narrowest portions
of the patient's vasculature (e.g., the iliac artery), balloon 28
can be advanced distally, as indicated by arrow 59 in FIG. 4, by
pushing balloon catheter 16 towards the nose piece 32 to position
the balloon within valve 12 for valve deployment. Valve 12 can then
be advanced further in the patient's vasculature to the treatment
site. As can be seen in FIG. 5, the balloon 28 typically is longer
than the valve so that when the balloon is positioned in the valve,
a distal end portion of the balloon extends into nose piece 32 and
a proximal end portion of the balloon remains in the distal end
portion of the guide catheter.
[0117] Alternatively, valve 12 can be advanced completely through
the vasculature to the treatment site in a position distal (as
described in this embodiment) or proximal (as described in other
embodiments below) to the location of balloon 28. Once valve 12
reaches the treatment site, the balloon can be moved into position
underneath the valve for deployment. It should be understood that
for each of the embodiments disclosed herein, the balloon can be
repositioned within the valve at any time after passing through the
narrow portions of the patient's vasculature, including immediately
after passing through the introducer sheath, at the treatment site
itself, or at some location in between.
[0118] FIG. 5 shows balloon 28 in an expanded state, with balloon
28 expanding valve 12. Slits 54, 56 allow nose piece 32 and guide
catheter 14 to at least partially expand with balloon 28. The
method and manner of inflating balloons is known and balloon 28 can
be inflated in any known manner. Once valve 12 is expanded to the
desired size, balloon 28 can be deflated, and balloon catheter 14
and the other elements of the delivery apparatus can be retracted
from the patient's vasculature.
[0119] Alternatively, instead of having one or more support members
formed into strips, a single cylindrical member formed of an
elastic material could be used. If the cylindrical member is formed
of a material of sufficient elasticity to expand to accommodate the
diameter of an expanded balloon, the cylindrical member can be
formed in a single or unitary piece of material, which is not cut
into multiple strips as discussed above.
[0120] FIG. 6 shows nose piece 32 formed with slits 54 to
accommodate expansion of the distal end portion of balloon 28.
Slits 54 define flaps 60 that can flex radially outward from each
other to form a larger opening. Accordingly, during expansion of
the balloon, if a portion of the distal end of the balloon 28 is
positioned under a proximal portion of the nose piece, the balloon
can still be fully inflated since the proximal portion of the nose
piece 32 can expand to accommodate the expanded balloon.
[0121] FIG. 7 shows another embodiment of a nose piece 32. It may
be desirable to position a jacket 62 over at least a portion of
flaps 60. Jacket 62 is desirably formed of an elastic, flexible
polymer that can expand when a balloon inflates forcing flaps 60
radially outward. Once the balloon is deflated, however, the
elastic properties of jacket 62 cause flaps 60 to return to their
normal (closed) position. Jacket 62 can be formed of a variety of
elastic materials, including, for example, urethane, silicone, and
latex. Alternatively, instead of wrapping a polymer around at least
a portion of flaps 60, the nose piece 32, or at least a portion of
nose piece 32, can be dipped into an elastic material (such as
those discussed above) to form the jacket 62. In this manner,
jacket 62 can be formed by coating the elastic material on the nose
piece 32 such that the coating acts in substantially the same
manner as the polymer wrap described above.
[0122] FIGS. 8-12 show another embodiment of a delivery apparatus
for delivering a valve 12 to a treatment site using a valve
carrying member. As discussed in more detail below, in this
embodiment the valve carrying member can take the form of an outer
sleeve. Outer sleeve 64 extends over the guide catheter 14 from a
distal end (shown in FIG. 8) to a proximal end near the proximal
end of the guide catheter 14 and can be independently manipulated
by a handle portion (not shown). The outer sleeve 64 can be
manipulated in a manner that is the same or similar to the
manipulation that the guide catheter is capable of, as discussed
above.
[0123] Outer sleeve 64 is attached to nose piece 32. Outer sleeve
64 can be attached to an inside or outside portion of nose piece
32; however, it is desirably attached to an inside portion so that
the proximal edge of the nose piece 32 can abut and limit movement
of the crimped valve 12 in the distal direction. Outer sleeve 64 is
desirably formed of Nitinol, stainless steel, or a polymer such as
nylon, PET, PEEK, PE, Pebax, Urethane, and PVC.
[0124] Valve 12 is initially crimped onto the distal end portion of
outer sleeve 64 as shown in FIG. 9. Desirably, outer sleeve 64 is
formed as a braid or with laser cuts, so that outer sleeve 64 can
expand radially during implantation of the valve 12 at the
treatment site. If desired, outer sleeve 64 can be formed with only
a portion of it braided or laser cut. The braided or cut portion
should include at least the portion of outer sleeve 64 where the
valve 12 is crimped onto outer sleeve 64, so that the portion of
the outer sleeve 64 that extends through valve 12 can be expanded
along with valve 12.
[0125] After valve 12 is in position for deployment (or, if
desired, sometime after the valve passes the narrowest portions of
the patient's vasculature), balloon 28 can be moved distally
relative to guide catheter 14 and positioned to extend through
valve 12, as shown in FIG. 10. FIG. 11 shows balloon 28 in an
expanded state. Once valve 12 is expanded to the desired diameter,
balloon 28 can be deflated (as shown in FIG. 12) and the delivery
apparatus can be retracted from the patient's vasculature.
[0126] FIGS. 13-15 show an embodiment where a valve 12 is crimped
onto an inner sleeve 66. Referring to FIG. 13, inner sleeve 66 is
similar to outer sleeve 64, except that it is positioned
inside--instead of outside--of guide catheter 14. Inner sleeve 66
desirably extends the length of guide catheter 14 and can be
independently manipulated at its proximal end to move inner sleeve
66 longitudinally relative to guide catheter 14. By positioning
inner sleeve 66 inside of guide catheter 14, the distal edge of
guide catheter 14 can abut the proximal end of crimped valve 12 and
prevent valve 12 from moving or sliding out of position. In
addition, as shown in FIG. 15, the distal end of guide catheter 14
can be formed with a lip 68 so that guide catheter 14 can seat
better against the proximal end of valve 12.
[0127] It is also desirable to attach the distal end of the inner
sleeve 66 to an inside portion of the proximal end of the nose
piece 32. By attaching inner sleeve 66 to an inside portion of nose
piece 32, valve 12 can be more securely held in position between
nose piece 32 and guide catheter 14.
[0128] FIG. 14 shows balloon 28 in its expanded state after it has
been advanced to a position extending through the portion of the
inner sleeve 66 on which the valve is mounted. Inflating the
balloon causes that portion of inner sleeve 66 and valve 12 to
expand. Once valve 12 is expanded to the proper diameter, balloon
28 can be deflated and retracted as discussed in the other
embodiments. FIG. 15 is a cross section view of the delivery
apparatus. Valve 12 includes an outer frame portion 70 and an inner
portion that includes leaflets 72. Valve 12 is positioned between
nose piece 32 and the distal end of catheter 14, which can include
a lip 68 to better mate with the frame portion 70 of valve 12.
[0129] The use of a braided or laser-cut outer or inner sleeve that
is formed of a metal, such as Nitinol, also permits valve 12 to be
repositioned after it has been partially expanded. In traditional
delivery apparatuses, the valve is crimped onto a balloon. If the
balloon is partially inflated and the surgeon observes that the
valve is not properly positioned, it is very difficult to
reposition the valve. First, the balloon must be deflated so that
the orifice is not occluded for too long a period. Because
expansion of a balloon occludes the orifice (such as the aortic
valve), the period that the balloon can be expanded at the
treatment site is relatively brief. Once the balloon is deflated,
however, there is nothing that is holding the valve in position
relative to the balloon. When using an inner or outer sleeve as
discussed above, however, the inner or outer sleeve is expanded
with the valve. Thus, the valve remains in position on the inner or
outer sleeve. If the surgeon observes that the valve is not
properly position, the surgeon can deflate the balloon and maneuver
the valve by manipulating the position of the inner or outer
sleeve. The metal sleeve can be collapsed down from the partially
expanded state by any known method. For example, a stretching force
can be applied to the metal sleeve to stretch or lengthen the metal
sleeve so that the diameter of the sleeve is reduced. This can be
achieved by applying forces at the proximal end of the metal sleeve
or at the distal end of the metal sleeve using, for example, rigid
wires.
[0130] FIG. 16 shows an embodiment in which a valve 12 is crimped
onto a delivery apparatus proximal to a balloon 28 of a balloon
catheter 16. Balloon catheter 16 includes an extension portion 74
that extends from a proximal end of balloon 28. The extension
portion 74 can be formed of the same material as balloon 28 and can
be an integral piece of balloon 28. Alternatively, extension
portion 74 can be a separate material that is formed of the same or
different material and which is bonded, welded, glued, or otherwise
attached between balloon 28 and balloon catheter 16 at bond areas
76. The extension portion 74 desirably has a smaller cross section
or profile than balloon 28, so that valve 12 can be crimped to a
smaller profile on extension portion 74 than it can on balloon 28.
Extension portion 74 can be formed of any suitable material, such
as the polymers discussed above, which include nylon, PET, PEEK,
PE, Pebax, Urethane, and PVC.
[0131] Balloon 28 can be attached to a nose piece 32. Desirably, a
distal portion of balloon 28 is attached to approximately the
mid-point of the nose piece 32. Nose piece 32 can be useful to
provide a more efficient tracking profile of the distal end of the
delivery apparatus through a patient's vasculature. For example,
the tapered shape of nose piece 32 as well as its more rigid
structure (as compared to balloon 28) can function to make delivery
of the valve through the vasculature more efficient. In particular,
nose piece 32 can be substantially hourglass shaped, as shown in
FIG. 16. By forming nose piece 32 with a proximal concave (tapered)
portion as shown in FIG. 16, when the nose piece 32 is moved
proximally to abut, or be adjacent to, the crimped valve (as shown
in FIG. 17), the concave portion can receive at least a portion of
the balloon. Thus, by moving the nose piece 32 so that it abuts the
crimped valve, a portion of the balloon can be received in the
concave portion, and a smooth, atraumatic profile can be achieved
to facilitate tracking of the valve over the aortic arch and when
crossing the stenotic valve.
[0132] Also, it may be desirable to include an elongated shaft
attached to nose piece 32. This elongated shaft 18 can provide
additional structure and support in guiding balloon catheter 16
through the patient's vasculature.
[0133] After valve 12 passes the narrowest portions of the
patient's vasculature (or, if desired, at some later position
including, for example, the point of deployment), balloon 28 can be
pulled back (moved proximally) by retracting balloon catheter shaft
16 at its handle (not shown) to position the balloon within valve
12, as shown in FIG. 17. FIG. 17 shows balloon 28 in an unexpanded
state. As described in more detail in other embodiments, when valve
12 is in position at the treatment site, valve 12 can be expanded
to the desired diameter by inflating balloon 28, balloon 28 can be
deflated with valve 12 secured by friction at the treatment site,
and the delivery apparatus can be retracted from the patient's
vasculature.
[0134] If desired, the configuration of FIG. 18 could be achieved
before insertion of the valve 12 into the vasculature of the
patient. That is, the hourglass shape of nose piece 32 can provide
a beneficial tracking profile, without regard to whether the
configuration shown in FIG. 18 is achieved inside or outside of the
patient's vasculature. However, as discussed in detail above,
moving the apparatus into the configuration shown in FIG. 18 while
in the patient's vasculature allows for a smaller insertion profile
which is desirable to facilitate insertion of the valve into the
patient's vasculature.
[0135] In addition, by providing an apparatus with a balloon distal
to the valve, it is possible to inflate the balloon to perform
valvuloplasty to open a stenotic heart valve, prior to moving the
balloon in position to expand the valve. In such a procedure, the
process of moving the balloon into position for expanding the valve
would be the same as discussed herein, except that it would occur
after (1) expanding the balloon to apply expansion forces to the
stenotic heart valve and (2) deflating the balloon so that it can
return to the state shown in FIG. 16.
[0136] FIG. 18 shows another embodiment where an expansion member
(second smaller balloon 84) is positioned inside balloon 28 and
valve 12 is crimped on top of the expansion member (second balloon
84). Because second balloon 84 is smaller in diameter than balloon
28, valve 12 can be crimped to a smaller diameter when crimped on
second balloon 84 than when crimped on balloon 28.
[0137] Second balloon 84 can serve to hold valve 12 in place as the
device is maneuvered through the patient's vasculature. In
addition, second balloon 84 can be separately expandable so that
second balloon 84 can partially expand valve 12 so that it is
easier to move balloon 28 in position within valve 12 for
deployment of the valve at the treatment site. Second balloon 84
can be attached to the end of a shaft 86. Shaft 86 has a lumen that
can be in fluid connection with a fluid source and second balloon
84. Fluid can be transported through the lumen of shaft 86 and into
second balloon 84 to cause second balloon 84 to inflate and at
least partially expand valve 12. Referring to FIG. 19, second
balloon 84 is shown in an inflated state, with valve 12 being
partially expanded. After partially expanding valve 12, second
balloon 84 can be deflated and balloon 28 can be pulled back (moved
proximally) into position beneath the partially expanded valve 12.
After balloon 28 is moved back into position extending through the
partially expanded valve 12, valve 12 can then be expanded to the
desired diameter by inflating balloon 28, balloon 28 can be
deflated with valve 12 expanded in the desired position at the
treatment site, and the delivery apparatus can be retracted from
the patient's vasculature.
[0138] FIG. 20 is another embodiment of a delivery apparatus.
Similar to the embodiment shown in FIGS. 16 and 17, balloon
catheter 16 has an extension portion 74 that has a smaller diameter
than balloon 28, so that valve 12 can be crimped to a smaller
profile on extension portion 74 than it can on balloon 28. The
extension portion 74 can be formed of the same material as balloon
28 and an integral piece of balloon 28. Alternatively, extension
portion 74 can be a separate material that is formed of the same or
different material and which is bonded, welded, glued, or otherwise
attached between balloon 28 and balloon catheter 16 at bond areas
76. The apparatus shown in FIG. 20 also includes a dilator 88 and a
stopper 90. Dilator 88 and stopper 90 can be attached to the inside
surface of the extension portion 74 or to the outside surface of
the shaft of nose catheter 18 (if a nose catheter is included).
Dilator 88 and stopper 90 can both serve to hold the crimped valve
12 in position on extension portion 74.
[0139] Stopper 90 can be generally cylindrical in shape, with one
or more openings passing through its center to accommodate the
elongated shaft of the nose catheter and allow fluid to flow into
the balloon. When extension portion 74 is pushed forward or pulled
back relative to guide catheter 14, the thin extension portion is
susceptible to buckling or bunching. Stopper 90 can reduce the
buckling of the thin layer of material by adding structural
strength to extension portion 74.
[0140] Dilator 88 can be used to partially expand valve 12 as the
balloon 28 and the dilator 88 are moved in the proximal direction
relative to the valve so that it is easier to position balloon 28
within valve 12 when preparing the valve to be expanded by balloon
28. FIGS. 21A-21C show more details of dilator 88. The cone shape
of the dilator 88 permits valve 12 to expand smoothly as the
dilator is moved proximally through the valve so that the balloon
can slide into the valve more easily. Dilator 88 or stopper 90 can
further include a marker, such as a radiopaque marker, to provide a
reference point for a surgeon during the implantation
procedure.
[0141] It should be understood that in the embodiments disclosed
here, balloon 28 can be either pushed (or pulled) within valve 12
or valve 12 can be pushed (or pulled) onto balloon 28. For example,
in the above embodiment, it may be desirable to push valve 12 over
dilator 88 and onto balloon 28. The distal end of guide catheter 14
abuts the wire frame of valve 12 and by pushing or moving guide
catheter 14 distally (relative to the balloon catheter 16), valve
12 can be moved into position for deployment on top of balloon
18.
[0142] Referring to FIG. 21A, dilator 88 has an opening 92 through
which nose catheter 18 can pass. In addition, as shown in FIG. 21B,
dilator 88 can have two slotted sections 94. Slotted sections 94
extend longitudinally along the length of dilator 88. Slotted
section 94 permit fluids to flow between the front and back areas
of dilator 88.
[0143] FIGS. 22A-22D show a flex adapter 96 and FIGS. 23A and 23B
show a flex adapter 96 positioned on a distal end of a guide
catheter 14. Flex adapter 96 has a plurality of spaced-apart
fingers 98 (three in the illustrated embodiment). Flex adapter 96
can be positioned on the distal end of guide catheter 14 and an end
member 100 can be overmolded and/or laser welded to the distal end
of guide catheter 14. End member 100 can be overmolded onto the
three spaced-apart fingers 98 so that it has three sections
corresponding to the three spaced-apart fingers 98.
[0144] Flex adapter 96 can be formed of a resilient material, such
as Nitinol, that naturally pushes the three sections of the end
member 100 outward, but at the same time permits the three sections
to be forced inward under pressure to form a lower profile. Thus,
the three sections of end member 100 can be compressed to a smaller
profile when inserted into an introducer sheath. Accordingly, the
distal end of the guide catheter 14 can fit into the introducer
sheath when subjected to the inwardly directed radial pressures of
the introducer sheath. Upon exiting the introducer sheath, however,
the three sections 100 of guide catheter expand again to the
profile shown in FIG. 23A. The radially outward expansion of the
three sections 100 causes the distal edge of guide catheter 14 to
butt up against the frame of the crimped valve 12, which helps
maintain the position of the valve 12 relative to the guide
catheter 14 during maneuvering of the delivery apparatus.
[0145] Also, the expansion of the three sections 100 (shown in FIG.
23A) can make it easier for a balloon member to be pulled or pushed
underneath a crimped valve in the manners discussed above. In
addition, the sectioned flex adapter 96 and the sectioned distal
end of the guide catheter 14 permit expansion of the distal end of
the guide catheter 14 so that a balloon can be expanded while the
balloon is at least partially contained by the distal end of the
guide catheter 14.
[0146] FIG. 24 shows another embodiment of a delivery apparatus
wherein a valve 12 can be located and crimped distal to a balloon
28 on an inner sleeve 106. A distal end of a guide wire 109 extends
beyond the distal end of valve 12. A hypotube 111 can extend at
least partially into the valve to facilitate the transfer of valve
12 to the delivery apparatus.
[0147] The inner sleeve 106 is desirably formed of one or more of
the materials discussed above, including Nitinol, stainless steel,
or polymers such as nylon, PET, PEEK, PE, Pebax, Urethane, and PVC.
Valve 12 can be temporarily secured to a wire loop 102 and a distal
end of a separate wire member 107. Valve 12 is desirably tied to
wire member 107 and wire loop 102 using a suture 104 or other type
of temporary tying connection. Desirably, valve 12 is tied to wire
loop 102 and wire member 107 in such a manner that the suture 104
connection can be released by pulling on a proximal end of wire
member 107, which can extend the entire length of the guide
catheter 14. In operation, by pulling or moving wire member 107 in
the proximal direction, valve 12 is released and suture 104 remains
secured to wire loop 102. Wire loop 102 can extend the length of
the guide catheter 14 and can be removed from guide catheter 14 by
pulling wire loop 102 through the shaft of the guide catheter
14.
[0148] By tying valve 12 so that its movement is restricted in the
distal direction relative to the distal end of guide catheter 14,
balloon 28 can be more easily pushed under valve 12. The tying of
valve 12 to the distal end of the guide catheter 14, as discussed
above, can be combined with each of the embodiments herein to
further secure the valve 12 relative to the guide catheter.
[0149] Certain embodiments above discuss using second balloon
elements to partially expand valve 12 to make it easier to move the
main balloon 28 into position beneath valve 12. FIG. 24 illustrates
another example of the use of a second balloon 108 to facilitate
positioning of main balloon 28. Second balloon 108 can be
positioned inside of balloon 28 at the distal end of balloon 28.
The distal end of balloon catheter 16 can be moved partially under
a crimped valve 12. Second balloon 108 can then be inflated via a
second balloon inflation lumen 110 so that the portion of second
balloon 108 that is within crimped valve 12 partially expands valve
12. If desired, second balloon 108 can then be deflated and moved
distally so that second balloon 108 is disposed further within
valve 12. Second balloon 108 can then be inflated again so that the
area of valve 12 that is now on top of second balloon 108 can be
expanded. By deflating second balloon 108 and moving it distally
further within valve 12 until the entire valve 12 is expanded (or
until valve 12 is expanded sufficiently to receive balloon 28
within it), valve 12 can be uniformly, partially expanded so that
balloon 28 can be easily positioned within valve 12 for deployment
of the valve. That is, if desired, second balloon 108 can be
inflated, deflated, and repositioned repeatedly so that valve 12 is
sufficiently expanded to permit the larger main balloon 28 to be
maneuvered beneath valve 12.
[0150] When crimping the valve proximal to the balloon in the
embodiments discussed above, the valve is desirably crimped so that
the leaflets fold outward, toward the outflow end of the valve and
in the proximal direction of the delivery apparatus. In this
manner, when pulling the balloon back (proximally) through the
valve so that the balloon is positioned beneath the valve, the
balloon is pulled back in the direction of the folded leaflets.
Thus, the movement of the balloon into position beneath the valve
is more efficient and the likelihood that the leaflets will
interfere with the movement of the balloon is minimized. Damage to
the leaflets from the movement of the balloon is also less likely
to occur because the movement of the balloon is in the same
direction as the leaflets of the valve.
[0151] FIGS. 25-27 show an embodiment of an apparatus for
mechanically maneuvering a catheter or other tube through the
vasculature of a patient. In the below embodiment, a method and
apparatus is disclosed in which an advancement apparatus is clamped
over a guide catheter as it is being inserted through a femoral
access introducer sheath and seal housing. The apparatus
facilitates the advancement of the guide catheter through the
introducer sheath by reducing the amount of force a surgeon must
apply to pass the guide catheter through the introducer sheath,
while at the same time providing the surgeon with sufficient
control of the advancement of the guide catheter. Although the
apparatus is discussed below in the context of advancing a catheter
for deployment of a prosthetic valve, the apparatus can be utilized
in other operations or procedures where a mechanical assist is
necessary or useful to push or pull one tube or catheter axially
relative to another catheter or platform.
[0152] Advancement apparatus 110 includes a top member 112 and a
bottom member 114. FIG. 25 depicts the top member 112 and bottom
member 114 separate from one another, while FIG. 26 shows the top
member 112 and bottom member 114 in closed position and locked onto
an introducer sheath 119 (shown in FIG. 27) and a guide catheter
116. The top and bottom members 112, 114 are closed onto and over
guide catheter 116 in the direction of arrow A shown in FIG. 25. In
addition, top and bottom members 112, 114 close onto and over a
proximal end of a locking member 118, which prevents introducer
sheath 119 from moving relative to apparatus 110.
[0153] Introducer sheath locking member 118 (or retaining member)
locks onto the proximal end of an introducer sheath 119. The
mechanism for locking onto the sheath housing can be any mechanical
locking mechanism, including, for example a snap-fit or press-fit
connection that firmly holds the sheath housing to the sheath
locking member 118. Alternative or additional mechanical means may
be useful to ensure that the locking member 118 does not move
relative to the sheath housing.
[0154] The guide catheter 116 is disposed between a top gear member
120 and a bottom gear member 122. Top and bottom gear members 120,
122 have a top and bottom axle member 124, 126 (respectively). Top
and bottom axle members 124, 126 fit into openings 130, 132
(respectively) in the top and bottom members 112, 114. The top and
bottom gear members 120, 122 can have teeth 128, which frictionally
engage the outer surface of guide catheter 116. The advancement
apparatus includes a drive member 134, which in FIG. 27 is a
rotating knob. Drive member 134 drives the bottom gear member 122,
the teeth of which engage the teeth of the top gear member 120. By
rotating the drive member 134, the teeth on the bottom gear member
122 drive guide catheter 116 in the direction of the rotating
force. In addition, since the teeth on the bottom gear member 122
also drive the teeth on the top gear member 120, the top gear
member 120 also drives guide catheter 116 in the direction of the
rotating force.
[0155] Because locking member 118 of advancement apparatus 110
locks onto the sheath housing, the resultant forces are canceled
out and the advancement of the guide catheter through the
introducer sheath can be more easily controlled. In addition,
because the net force is zero, it is less likely that the
introducer sheath will be inadvertently pulled out of the patient's
body during advancement of the guide catheter by a surgeon.
[0156] Teeth 128 include spanning grip members 129, which span
between opposing teeth 128 that are on opposite sides of a gear
member. Spanning grip members 129 form a concave arc between
opposing teeth 128, with the arc tracking the general shape of the
shaft of guide catheter 116. Grip members 129 desirably comprise an
elastomeric material that is selected to provide sufficient
gripping force for gripping the guide catheter. The friction caused
by pressing spanning grip members 129 against guide catheter 116
causes spanning grip members 129 to grip the shaft of the guide
catheter 116 to ensure that a steady application of force to the
drive member 134 results in a steady movement of the guide catheter
116.
[0157] The gear members can be provided with one-way bearings so
that the drive member 134 can be used as a ratchet handle. That is,
drive member 134 can be configured such that it can be advanced
only in one direction. When the drive member 134 is formed with a
one-way ratcheting mechanism, the knob (or other manual adjustment
member) can be released during operation without the guide catheter
from being forced backwards by forces within the introducer sheath
that are resisting the advancement of the guide catheter. This also
reduces the risk that the guide catheter 116 will be pulled
backwards by the surgeon while it is in the introducer sheath,
which could damage the valve or cause it to be dislodged from its
crimped location relative on the delivery apparatus. When the valve
has cleared the distal end of the introducer sheath, the
advancement apparatus 110 can be removed from the guide catheter to
allow tracking and deployment to continue without the advancement
apparatus 110.
[0158] FIG. 27 shows the advancement apparatus with two gears that
have teeth on both the drive wheel (bottom gear member 122) and the
idler wheel (top gear member 120). In this manner, guide catheter
116 is driven by both wheels at the same time. However, the driving
mechanism can vary and the guide catheter 116 can be driven by one
gear or more than two gear members. In addition, the gearing or
gear ratio of the driving mechanism can vary. The gear members can
also vary in size and holding power (break torque), and can be
configured to provide an override at a certain torque. In addition,
various handle options can be attached to advancement apparatus
110.
[0159] Friction between the gear members and the guide catheter is
very important to provide for a controlled delivery of guide
catheter 116 by advancement apparatus 110. Accordingly, the size,
shape, rigidity, and surface of gear members can vary to provide an
appropriate amount of friction (or grip) necessary to drive the
guide catheter.
[0160] FIGS. 28-30 show alternative gear members that can be used
to drive guide catheter 116 in connection with the advancement
apparatus 110. FIG. 28 shows a gear member 136 with a central
concave shape with recesses 138 for gripping a guide catheter. The
number and depth of the recesses can vary depending on the amount
of friction or grip needed for the application. Gear member 136 can
be a single driving gear member without gear teeth to connect it to
a second gear member. Alternatively, gear member 136 can have gear
teeth on it so that two gear members can drive a guide
catheter.
[0161] FIG. 29 shows gear member 136 with an additional gripping
material 140 disposed in at least some of recesses 138. Gripping
material 140 can be attached to recesses 138 in any convention
manner, and can be attached to some or all of the recesses 138.
Gripping material 140 provides an increased frictional contact
between gear member 136 and guide catheter 116. Gripping material
140 can be an elastomeric material, such as silicone, rubber, or
other elastic polymers. These materials are capable of increasing
the friction between gear member 136 and guide catheter 116, but
have a contact surface that will not cause damage to the surface of
guide catheter 136 during advancement.
[0162] FIG. 30 shows another embodiment of an advancement apparatus
that has a top gear member 142 and a bottom gear member 144. Each
of the top and bottom gear members 142, 144 comprise two o-ring
members 146. Two o-ring members 146 on each gear member engage and
drive guide catheter 116 when drive member 134 is rotated. Although
FIG. 30 shows the bottom gear member 144 as the only driving
member, the advancement apparatus of FIG. 30 could be modified with
appropriate gearing so that both the top and bottom gear members
drive the guide catheter 116. The o-rings can be formed of a
variety of materials, including the materials discussed above with
regard to the gripping material. The material of the o-rings is
desirably selected so that the o-rings will not cause damage to the
surface of the guide catheter when frictionally engaged with the
guide catheter during advancement of the guide catheter through the
introducer sheath.
[0163] In another embodiment, a flex indicating device can be used
in connection with a guide catheter that is capable of flexing at
its distal end. Catheters, such as guide catheters, can be provided
with a flexing ability so that the catheter can be steered through
a patient's vasculature. However, when steering a catheter through
a patient's vasculature it can be difficult to determine how much
the catheter has been flexed at any given moment.
[0164] Referring to FIG. 31, flex indicating device 150 provides a
surgeon with a device for measuring the relative amount of flex of
the distal end of a catheter. In addition, the indicator provides a
visual and tactile response at a proximal handle end of the device,
which provides a surgeon with an immediate and direct way to
determine the amount of flex of the distal end of the catheter.
[0165] Flex indicating device 150 comprises a flex activating
member 154, an indicator pin 156, and a handle portion 158. Flex
indicating device is configured to flex a distal end of an
elongated shaft 152 of a catheter (e.g., a guide catheter) by
pulling on a wire (not shown) that is attached to the distal tip of
the shaft 152 and which extends the length of the shaft. The
pulling of the wire is achieved by rotating flex activating member
154 (e.g., a knob) that has female threads running down its
length.
[0166] Referring to FIG. 32, flex activating member 154 comprises
an adjustment knob 155 and a shaft 157 extending from the knob. The
shaft 157 has an internally threaded surface portion 160 that mates
with a slide nut that has male threads. The proximal end of the
wire is attached to the slide nut via a crimp pin and a counter
bored hole or slot. As the flex activating member 154 is rotated,
the slide nut translates along the internally threaded surface
portion 160 towards the proximal end of the flex indicating device
150, thereby causing the distal end of the catheter 152 to flex. As
the amount of the rotation of the flex activating member 154
increases, the slide nut moves further toward the proximal end of
the flex indicating device 150 and the amount of flex of the distal
end of catheter 152 increases.
[0167] The shaft 157 also includes an externally threaded surface
portion 162. As shown in FIG. 37, an extending portion 166 of
indicator pin 156 mates with the externally threaded surface
portion 162 of flex activating member 154. The shaft 157 extends
into the handle portion 158 and the indicator pin 156 is trapped
between the externally threaded surface portion 162 and the handle
portion 158, with a portion of the indicator pin 156 extending
upward into a longitudinal slot 164 of the handle. As the knob 155
rotated to increase the flex of the distal end of the shaft of
catheter 152, indicator pin 156 tracks the external threaded
portion 162 of the flex activating member and moves in the proximal
direction inside of slot 164. The greater the amount of rotation of
the flex activating member 154, the further indicator pin 156 moves
towards the proximal end of handle 158. Conversely, rotating the
knob 155 in the opposite direction decreases the flex of the distal
end of the shaft of the catheter and causes corresponding movement
of the indicator pin 156 toward the distal end of the handle.
[0168] Referring to FIGS. 35A and 35B, the flex indicating device
150 desirably includes indicia 168 that indicate the amount of flex
of the distal end of catheter 152. Indicia 168 can identify the
amount of flex in any of a variety of manners. For example, FIG. 35
shows indicia 168 depicting the amount of flex using a triangular
marking system while FIG. 36 shows indicia 168 depicting the amount
of flex using numbers.
[0169] The handle portion 158 is shown in greater detail in FIG.
36. As discussed above, the flex indicating device 150 (e.g., a
guide catheter) includes a handle portion 158 and an elongated
guide tube, or shaft, 152 extending distally therefrom. The guide
tube 152 defines a lumen 175 sized to receive the shaft of the
balloon catheter and allow the balloon catheter to slide
longitudinally relative to the guide catheter. The distal end
portion of the guide tube 152 comprises a steerable section 188,
the curvature of which can be adjusted by the operator to assist in
guiding the apparatus through the patient's vasculature, and in
particular, the aortic arch.
[0170] The handle portion 158 includes a main body, or housing, 159
formed with a central lumen 161 that receives the proximal end
portion of the guide tube 152. The handle portion 158 can include a
side arm 62 (as shown in FIG. 1) defining an internal passage which
fluidly communicates with the lumen 161. A stopcock can be mounted
on the upper end of side arm 62.
[0171] The handle portion 158 can be operatively connected to the
steerable section and functions as an adjustment to permit operator
adjustment of the curvature of the steerable section via manual
adjustment of the handle portion. In the illustrated embodiment,
for example, the handle portion 158 includes an inner sleeve 190
that surrounds a portion of the guide tube 152 inside the handle
body 159. A threaded slide nut 192 is disposed on and slidable
relative to the sleeve 190. The slide nut 192 is formed with
external threads that mate with internal threads of an adjustment
knob 155. Sleeve 190 also has an external threaded portion that
mates with an extension member of a flex indicating member 156.
Flex indicating member 156 is shown in more detail in FIG. 37.
[0172] Slide nut 192 can be formed with two slots formed on the
inner surface of the nut and extending the length thereof. Sleeve
190 can be formed with longitudinally extending slots that are
aligned with the slots of the slide nut 192 when the slide nut is
placed on the sleeve. Disposed in each slot is a respective
elongated nut guide, which can be in the form of an elongated rod
or pin. The nut guides extend radially into respective slots in the
slide nut 192 to prevent rotation of the slide nut 192 relative to
the sleeve 190. By virtue of this arrangement, rotation of the
adjustment knob 155 (either clockwise or counterclockwise) causes
the slide nut 192 to move longitudinally relative to the sleeve 190
in the directions indicated by double-headed arrow 172.
[0173] One or more pull wires 174 connect the adjustment knob 155
to the steerable section 188 to produce movement of the steerable
section upon rotation of the adjustment knob. In certain
embodiments, the proximal end portion of the pull wire 174 can
extend into and can be secured to a retaining pin 180, such as by
crimping the pin 180 to the pull wire. The pin 180 is disposed in a
slot in the slide nut 192. The pull wire 174 extends from pin 180,
through a slot in the slide nut, a slot 200 in the sleeve 190, and
into and through a pull wire lumen in the shaft 152. The distal end
portion of the pull wire 174 is secured to the distal end portion
of the steerable section 188.
[0174] The pin 180, which retains the proximal end of the pull wire
174, is captured in the slot in the slide nut 192. Hence, when the
adjustment knob 155 is rotated to move the slide nut 192 in the
proximal direction, the pull wire 174 also is moved in the proximal
direction. The pull wire pulls the distal end of the steerable
section 188 back toward the handle portion, thereby bending the
steerable section and reducing its radius of curvature. The
friction between the adjustment knob 155 and the slide nut 192 is
sufficient to hold the pull wire taut, thus preserving the shape of
the bend in the steerable section if the operator releases the
adjustment knob 155. When the adjustment knob 155 is rotated in the
opposite direction to move the slide nut 192 in the distal
direction, tension in the pull wire is released. The resiliency of
the steerable section 188 causes the steerable to return its
normal, non deflected shape as tension on the pull wire is
decreased. Because the pull wire 174 is not fixed to the slide nut
192, movement of the slide nut in the distal direction does not
push on the end of the pull wire, causing it to buckle. Instead,
the pin 180 is allowed to float within the slot of the slide nut
192 when the knob 155 is adjusted to reduce tension in the pull
wire, preventing buckling of the pull wire.
[0175] In particular embodiments, the steerable section 188 in its
non-deflected shape is slightly curved and in its fully curved
position, the steerable section generally conforms to the shape of
the aortic arch. In other embodiments, the steerable section can be
substantially straight in its non-deflected position.
[0176] The handle portion 158 can have other configurations that
are adapted to adjust the curvature of the steerable section 188.
One such alternative handle configuration is shown co pending U.S.
patent application Ser. No. 11/152,288 (published under Publication
No. US2007/0005131), which is incorporated herein by reference in
its entirety. Additional details relating to the steerable section
and handle configuration discussed above can be found in U.S.
patent application Ser. No. 11/852977 (published as U.S.
Publication No. US2008/0065011), which is incorporated herein by
reference in its entirety.
[0177] The indicator pin can be formed in a variety of shapes. For
example, as shown in FIGS. 38A and 38B, the indicator pin can have
one or more extending portions 166. Additional extending portions
may be useful to stabilize the indicator pin in the slot, as well
as to provide a more accurate reading or measurement of flex.
[0178] FIGS. 39A-39C show an alternative embodiment of a delivery
apparatus, indicated at 500. The delivery apparatus 500 allows a
valve 12 to be mounted on a balloon 28 of a balloon catheter inside
a body vessel. The balloon catheter can have a construction similar
to the balloon catheter shown in FIGS. 2A and 2B except that in the
embodiment of FIGS. 39A-39C, the balloon catheter shaft 526 has a
distal end portion 504 that extends distally from the balloon 28
and an annular tapered wedge 502 is disposed on the distal end
portion 504 adjacent the balloon. The tapered wedge 502 functions
to expand the valve to facilitate positioning the same on the
balloon inside the body, as further described below. The wedge 502
desirably is made from a low-friction material, such as nylon, to
allow the valve to easily slide over the wedge and onto the
balloon.
[0179] The delivery apparatus includes a nose catheter comprising a
shaft 506 and a nose piece 508 connected to the distal end of the
shaft 506. The nose catheter shaft 506 can have a guide wire lumen
to receive a guide wire 540 so that the apparatus can be advanced
over the guide wire with the guide wire passing through the lumen.
The delivery apparatus 500 can further include a guide catheter
comprising a guide catheter shaft 22 and an elongated cover 510
extending from the distal end of the shaft 22. The nose catheter,
balloon catheter, and guide catheter are moveable longitudinally
relative to each other and can have locking mechanisms at the
proximal end of the apparatus for retaining the catheters at
selected longitudinal positions relative to each other, as
described in detail above.
[0180] As shown in FIG. 39A, the valve 12 is initially mounted in a
crimped state on the nose catheter shaft 506 between the nose piece
508 and the tapered wedge 502, rather than on the balloon prior to
inserting the delivery apparatus into the body. The valve is
crimped onto the nose catheter shaft such that that valve can still
move along the shaft when it is desired to place the valve on the
balloon 28. The nose piece 508 can be formed with a stepped bore
comprising a first bore portion 512 and a second, enlarged bore
portion 514 at the proximal end of the nose piece. The stepped bore
can be formed with an annular shoulder 516 extending between the
first and second bore portions and adapted to engage the distal end
of the valve 12 when the valve is inserted into the second portion
514. The nose piece 508 can have an outer surface that tapers in a
direction toward the distal end of the nose piece 508 to provide
atraumatic tracking through tortuous vasculature. The cover 510,
which can be optional, is adapted to extend over and cover the
balloon 28, the wedge 502, and at least a proximal end portion of
the valve 12 when the valve is positioned on the nose catheter
shaft for delivery. In the illustrated embodiment, the distal end
of the cover 510 can be positioned to abut the proximal end of the
nose piece 508 so as to completely enclose the valve during
delivery. In alternative embodiments, the cover 510 can be shorter
in length so that less of the outer surface of the valve or the
balloon is covered during delivery.
[0181] The nose piece 508, when moved proximally relative to the
balloon catheter (in the direction indicated by arrow 518), pushes
the valve 12 over the wedge 502 and onto the balloon 28. As the
valve passes over the wedge, the valve expands slightly to
facilitate positioning the same on the balloon. The balloon
catheter shaft 26 can have radiopaque markers 520 (FIG. 39A) to
assist the operator in aligning the valve at the proper location on
the balloon. The nose piece can have an outer layer 522 formed from
a relatively soft and flexible material and an inner layer 524
formed from a relatively harder material. The inner layer 524 in
the illustrated embodiment forms the shoulder 516 and the inner
surface of the first bore portion 512. In this manner, the nose
piece exhibits sufficient rigidity to push the valve 12 over the
wedge and onto the balloon and provides a soft outer surface to
minimize trauma to the body vessels. For example, the outer layer
522 can be made of 55D Pebax.RTM. and the inner layer can be made
of 72D Pebax.RTM., which is stiffer than 55D Pebax.RTM..
[0182] The section of the delivery apparatus mounting the valve
typically defines the maximum outer diameter of the apparatus
inserted into the body. By mounting the valve 12 on the nose
catheter shaft rather than on the balloon prior to insertion into
the body, the valve 12 can be crimped to a smaller diameter than if
the valve is mounted on the balloon. Accordingly, the maximum outer
diameter of the delivery apparatus can be reduced for insertion
into and through the vasculature. As noted above, by reducing the
maximum diameter of the delivery apparatus, it is less occlusive to
the femoral artery and therefore the patient's leg can remain well
perfused during the procedure. In certain embodiments, the maximum
outer diameter of the cover 510 and the nose piece 508 (at its
proximal end) is about 0.223 inch, which is the maximum diameter of
the portion of the delivery apparatus that is inserted into the
body. The wedge 502 can have a diameter at its proximal end of
about 0.120 inch and the guide catheter shaft 22 can have an outer
diameter of about 0.184 inch.
[0183] Explaining now the operation of the delivery apparatus 500,
according to one embodiment, the valve 12 is initially mounted on
the nose catheter shaft and inserted into the nose piece 508 and
the cover 510. After a guide wire 540 is inserted into the body,
the proximal end of the wire extending from the body can be
inserted into the distal end of the guide wire lumen and the
delivery apparatus 500 can be inserted into a body vessel (e.g.,
the femoral artery) and advanced through the body (as depicted in
FIG. 39A). Alternatively, an introducer sheath can be inserted
first into the body vessel, for example if a cover 510 is not
provided to cover the valve 12. Subsequent to inserting the
introducer sheath, the delivery apparatus can be inserted through
the introducer sheath and into the body vessel.
[0184] When the distal end of the delivery apparatus is advanced to
a location that is convenient to slide the valve 12 onto the
balloon, the guide catheter is retracted proximally relative to the
balloon catheter to advance the valve and the balloon from the
cover 510. For example, if implanting a prosthetic valve within the
native aortic valve, the valve and the balloon can be advanced into
the ascending aorta or into the left ventricle where the valve can
then be moved onto the balloon. In any case, as shown in FIG. 39B,
the nose catheter can be retracted proximally to advance the valve
over the wedge 502 and onto the balloon 28. Markers 520 (FIG. 39A)
can be used to center the valve on the balloon. After mounting the
valve on the balloon, the nose catheter can be advanced distally so
as not to interfere with inflation of the balloon, as shown in FIG.
39C. The valve can then be positioned at the implantation site
(e.g., within the native aortic valve) and deployed by inflating
the balloon.
[0185] In another embodiment, an adjustment device is provided for
adjusting the position of a balloon relative to a crimped valve. As
described in the various embodiments above, a balloon catheter can
extend coaxially with a guide (or flex) catheter, and a balloon
member at the distal end of the balloon catheter can be positioned
proximal or distal to a crimped valve. As described above in more
detail, the balloon member and the crimped valve can enter the
vasculature of a patient through an introducer sheath and, once the
balloon member and the crimped valve reach a suitable location in
the body, the relative position of the valve and balloon member can
be adjusted so that the balloon member is positioned within the
frame of the valve so that the valve can be expanded at the
treatment site. The following embodiment provides an apparatus and
method for adjusting to the position of the balloon member relative
to the valve to achieve accurate alignment of the balloon member
within the valve prior to deployment of the valve at the treatment
site.
[0186] FIG. 40 shows an adjustment device 600. Adjustment device
600 can comprise a first portion (e.g., flex indicating portion
602), and a second portion (e.g., adjustment portion 604) located
proximal to the first portion. The first portion can be a flex
indicating device such as is shown and described with reference to
FIG. 31. Alternatively, the first portion could be a structure that
does not include flex indicating features.
[0187] As shown in FIG. 40, an elongated shaft 606 of a catheter
(e.g., a guide or flex catheter) extends into a distal end of
adjustment device 600. The elongated shaft 606 of the guide
catheter has a proximal end 620 (shown in FIG. 42) that terminates
within the first portion (flex indicating portion 602) of
adjustment device 600. As described in detail in the various
embodiments above, an elongated shaft 608 of a balloon catheter can
extend coaxially through the elongated shaft 606 of the guide
catheter. The balloon catheter can have a balloon member at a
distal end. The balloon catheter can also have a proximal portion
612 that defines an inner lumen that is in communication with a
lumen of the elongated shaft 608 of the balloon catheter and,
during inflation of the balloon member, with a fluid pressurizing
device (not shown). Proximal portion 612 can be located proximal to
the adjustment device 600.
[0188] As described in more detail in the previous embodiments,
when the delivery apparatus is introduced into the vasculature of
the patient, the balloon member can be disposed either proximal or
distal to a crimped valve member. For example, FIG. 16 depicts a
valve 12 that is crimped on a delivery apparatus proximal to a
balloon 28 of a balloon catheter 16. Prior to expansion of balloon
28 and deployment of valve 12 at the treatment site, balloon 28 is
moved relative to valve 12 so that balloon 28 is properly
positioned for inflation within the frame of valve 12. As discussed
below, adjustment device 600 can be used to move balloon 28
proximally into position within the frame of valve 12.
[0189] As shown in FIG. 40, a securing mechanism 610 can be
disposed in adjustment portion 604. Securing mechanism 610 can also
include a locking button 622 that can lock securing mechanism 610
in an open position, permitting the elongated shaft 608 to move
freely relative to the adjustment device 600. As discussed in more
detail below, locking button 622 can be slidably coupled with
securing mechanism 610 as shown in FIG. 42.
[0190] Referring to FIG. 41, securing mechanism 610 can comprise an
upper portion 614, an opening 616, and a lower portion 618. As
shown in FIG. 42, elongated shaft 608 passes through opening 616 of
securing member 610. Securing mechanism 610 is biased downward
(that is, downward with reference to FIG. 42) by spring 626. Spring
626 biases securing mechanism 610 by contacting lower portion 618
and providing a biasing force directed away from spring 626 towards
securing mechanism 610. Elongated shaft 608 is formed with one or
more grooved sections 624. As shown in FIG. 42, when a grooved
section 624 is engaged by a portion of securing mechanism 610 that
surrounds the opening 616 on the side of spring 626, the securing
mechanism secures the elongated shaft 608 and restricts further
movement of the elongated shaft 608 in the longitudinal direction
relative to adjustment portion 604.
[0191] As shown in FIG. 42, a proximal end 620 of elongated shaft
606 of the guide catheter terminates within the flex indicating
portion 602 of adjustment device 600. The proximal end 620 of
elongated shaft 606 of the guide catheter can be secured to flex
indicating portion 602 of adjustment device 600 to prevent movement
of the elongated shaft 606 relative to flex indicating portion 602.
Elongated shaft 606 can be secured to flex indicating portion 602
by using, for example, an adhesive or any type of mechanical
fastener. Accordingly, when securing mechanism 610 engages a
grooved section 624 of elongated shaft 608, the two shafts 606, 608
are each fixed in the longitudinal direction relative to respective
portions of the adjustment device 600. That is, shaft 608 is fixed
relative to adjustment portion 604 (i.e., the second portion of
adjustment device 600) and shaft 606 is fixed relative to flex
indicating portion 602 (i.e., the first portion of adjustment
device 600).
[0192] Adjustment portion 604 has an external gripping surface 628
that functions as a gripping knob or handle that can be rotated in
the directions shown by arrows 630 in FIG. 40. Adjustment portion
604 can have an internally threaded portion 632 and flex indicating
device portion 602 can have an externally threaded portion 634.
These threaded portions can mate (or screw) together and the
rotation of gripping surface 628 in a clockwise or
counter-clockwise direction (as shown by arrows 630) causes
adjustment portion 604 to move closer to, or further away from,
flex indicating portion 602, which in turn causes shaft 608 to move
axially relative to shaft 606. Accordingly, when a balloon member
and a crimped valve of a delivery apparatus have been advanced to a
location within the vasculature of a patient where it is desirable
to mount the valve on the balloon, adjustment device 600 can be
utilized to accurately change the position of the balloon member
relative to the guide catheter.
[0193] Accordingly, in operation, the elongated shaft 608 of the
balloon catheter can be maneuvered within the adjustment portion
604 of adjustment device 600 until a grooved section 624 of
elongated shaft 608 engages securing mechanism 610. FIG. 43A shows
elongated shaft 608 in a position securing mechanism 610 does not
engage a grooved section, and FIG. 43B shows elongated shaft 608 in
a position where a grooved section 624 is engaged by securing
mechanism 610. Because securing mechanism 610 is biased toward
elongated shaft 608, when a grooved section 624 passes through the
opening 616 of securing mechanism 610, securing mechanism 610
automatically grips the grooved section 624, restricting
longitudinal movement of elongated shaft 608 relative to adjustment
portion 604. Once the securing mechanism 610 engages a grooved
section 624, the longitudinal position of the balloon member can be
adjusted by rotating external gripping surface 628 to move the
elongated shaft 608 (and, by extension, the balloon member at the
distal end of elongated shaft 608) proximal or distal towards the
valve. During adjustment of the position of the balloon member
relative to the valve member, an imaging technique, such as
fluoroscopy, can be used to observe the relative positions of the
balloon member and valve.
[0194] As the external gripping surface 628 is rotated, adjustment
portion 604 can translate proximally (or distally), pulling
elongated shaft 608 and balloon member in the proximal direction
(or distal direction) relative to the flex indicating portion 602.
Thus, the position of elongated shaft 608 can be adjusted in a
relatively slow and controlled manner. After the balloon member of
the elongated shaft 608 is repositioned so that the valve is
properly mounted on the balloon member, securing mechanism 610 can
be released from its engagement with the grooved section by
pressing securing mechanism 610 towards the spring 626 (that is,
downward relative to FIGS. 43A-C).
[0195] It may be desirable at times to prevent securing mechanism
610 from locking onto the elongated shaft 608. Accordingly, locking
button 622 can be configured to lock securing mechanism 610 in an
"open" position against the bias of spring 626 such that the
securing mechanism cannot engage one of the grooved sections 624 in
the shaft 608. Locking button 622 can be coupled with securing
mechanism 610. Alternatively, locking button 622 can be disposed
adjacent to securing mechanism 610. An opening or slot 640 for
receiving a leg portion of the locking button 622 can be provided
in an adjacent wall of adjustment section 604. When securing
mechanism 610 is pressed against spring 626 into an unsecured
position, locking button 622 can be moved longitudinally so that
the leg portion of the locking button 622 slides into opening 640.
By sliding locking button 622 into opening 640, the securing
mechanism 610 can be locked in an "open" position, in which
elongated shaft 608 can move freely relative to adjustment portion
604. To release the locking button 622 from the "open" position,
the locking button 622 can be moved back to the "unlocked" position
by sliding the locking button 622 back and removing the leg portion
from opening 640. This allows the securing mechanism 610 to once
again engage the grooved sections 624 of the elongated shaft
608.
[0196] The amount of adjustment can vary based on the application
and the length of the threads of the adjustment device 600. A
desired length of available adjustment of the balloon member, for
example, can be between about 2-10 mm, and more desirably between
about 4-6 mm. Adjustment device 600 can be configured with threads
that permit the first portion and second portion to travel to a
predetermined distance from one another before the two portions
separate from one another. Desirably, however, the length of travel
is limited by a mechanical stop 636. Mechanical stop 636 can be
formed with (or attached to) one of the first or second portions
(e.g., flex indicating portion 602) and configured so that
mechanical stop 636 abuts a wall portion of the opposite portion
(e.g., adjustment portion 604). Mechanical stop 636 operates to
prevent the first and second portions (e.g., flex indicating
portion 602 and adjustment portion 604) from separating beyond a
predetermined amount.
[0197] Desirably, opening 616 in securing mechanism 610 is sized
and configured so that the elongated shaft 608 of the balloon
catheter will not rotate along with the rotation of the adjustment
portion 604. The securing mechanism and other elements of the
adjustment device 600 can be formed from a variety of materials,
including various plastics or metals, such as stainless steel.
[0198] There need only be one grooved section 624 that can engage
with securing mechanism 610. Alternatively, the elongated shaft 608
can be formed with multiple grooved sections. The additional
grooved sections can be positioned so that it is possible to adjust
the relative location of the balloon member to the guide catheter
at other times in the procedure, including during delivery of the
valve to the treatment site or during retraction of the balloon
member from the vasculature of the patient. Desirably, grooved
sections 624 are positioned at locations on the elongated shaft 608
so that when the grooved section 624 engages with securing
mechanism 610, the balloon member is relatively close to the
desired position within the crimped valve. In this manner, the
amount of distance of travel that is available between the
adjustment portion 604 and the flex indicating portion 602 will be
sufficient to mount the valve on the balloon member.
[0199] It should be noted that the location of the threaded
portions of the adjustment device 600 can be reversed. That is,
adjustment portion 604 can have an externally threaded portion and
flex indicating device portion 602 can have an internally threaded
portion. In addition, for embodiments where the balloon member is
initially positioned proximal to the valve member, the adjustment
device 600 can be configured so that the balloon member can be
manipulated to move distally to be positioned within the frame of
the valve member.
[0200] In view of the many possible embodiments to which the
principles of the disclosed invention may be applied, it should be
recognized that the illustrated embodiments are only preferred
examples of the invention and should not be taken as limiting the
scope of the invention. Rather, the scope of the invention is
defined by the following claims. We therefore claim as our
invention all that comes within the scope and spirit of these
claims.
* * * * *