U.S. patent application number 13/716377 was filed with the patent office on 2013-05-16 for catheter-based annuloplasty system and method.
This patent application is currently assigned to MEDTRONIC, INC.. The applicant listed for this patent is Medtronic, Inc.. Invention is credited to Stephen Kuehn.
Application Number | 20130123913 13/716377 |
Document ID | / |
Family ID | 44276333 |
Filed Date | 2013-05-16 |
United States Patent
Application |
20130123913 |
Kind Code |
A1 |
Kuehn; Stephen |
May 16, 2013 |
Catheter-Based Annuloplasty System and Method
Abstract
A catheter-based annuloplasty system for use in repairing a
heart valve having leaflets and a valve annulus, includes a
delivery catheter having a proximal end and a distal end, and an
expandable stent disposed on the distal end of the catheter. An
adjustable annuloplasty ring is disposed on the expandable stent
and is configured to expand and contract in response to expansion
and contraction of the stent.
Inventors: |
Kuehn; Stephen; (Woodbury,
MN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Medtronic, Inc.; |
Minneapolis |
MN |
US |
|
|
Assignee: |
MEDTRONIC, INC.
Minneapolis
MN
|
Family ID: |
44276333 |
Appl. No.: |
13/716377 |
Filed: |
December 17, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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12761007 |
Apr 15, 2010 |
8357195 |
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13716377 |
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Current U.S.
Class: |
623/2.11 |
Current CPC
Class: |
A61F 2250/0004 20130101;
A61F 2/2466 20130101; A61B 2017/00783 20130101; A61F 2/2445
20130101; A61F 2/2442 20130101 |
Class at
Publication: |
623/2.11 |
International
Class: |
A61F 2/24 20060101
A61F002/24 |
Claims
1. A catheter-based annuloplasty system for use in repairing a
heart valve having leaflets and a valve annulus, comprising: a
delivery catheter having a proximal end and a distal end; an
expandable stent disposed on the distal end of the catheter; and an
adjustable annuloplasty ring disposed on the expandable stent
configured to expand and contract in response to expansion and
contraction of the stent, wherein the adjustable ring includes at
least one tissue attachment member configured to be attached to the
valve annulus via movement of the expandable stent.
2. The annuloplasty system of claim 1, wherein the adjustable ring
includes a plurality of tissue attachment members shaped for
penetration into the valve annulus and configured to be triggered
from a spring-loaded tensioned state to a relaxed state.
3. The annuloplasty system of claim 2, wherein each tissue
attachment member comprises: a first prong portion extending from a
first circular spring portion; a second prong portion extending
from a second circular spring portion; and a cross-member
connecting the first and second circular spring portions.
4. The annuloplasty system of claim 3, wherein the adjustable ring
extends through the first and second circular spring portions of
each of the tissue attachment members.
5. The annuloplasty system of claim 3, wherein the cross-member
includes a feature configured to be connected to hold the
adjustable ring adjacent to the expandable stent.
6. The annuloplasty system of claim 2, and further comprising: a
plurality of tissue attachment retaining members disposed on the
expandable stent and configured to hold the tissue attachment
members in the tensioned state.
7. The annuloplasty system of claim 6, wherein the tissue
attachment retaining members are configured to release the tissue
attachment members from the tensioned state when the adjustable
ring is adjacent to the valve annulus, thereby causing the tissue
attachment members to transition to the relaxed state and anchor
the adjustable ring to the valve annulus.
8. The annuloplasty system of claim 7, wherein the adjustable ring
is configured to be adjusted in size after the adjustable ring has
been anchored to the valve annulus.
9. The annuloplasty system of claim 6, wherein the tissue
attachment retaining members are formed of a shape memory
material.
10. The annuloplasty system of claim 1, wherein the adjustable ring
comprises a plurality of interconnected cylindrically-shaped ring
segments.
11. The annuloplasty system of claim 10, wherein each of the ring
segments includes a plurality of tabs that extend away from a body
of the segment parallel to a surface of the adjustable ring.
12. The annuloplasty system of claim 11, wherein adjacent ones of
the tabs in each ring segment are separated by a gap, and wherein
each tab of each segment is positioned within one of the gaps of an
adjacent segment.
13. The annuloplasty system of claim 10, wherein axial twisting of
the adjustable ring causes a separation between adjacent segments
and an increase in an internal diameter of the adjustable ring.
14. The annuloplasty system of claim 10, wherein a first end of the
ring is co-axially aligned with and inserted into a second end of
the ring.
15. The annuloplasty system of claim 14, wherein contraction of the
stent causes the first end of the ring to extend farther into the
second end of the ring, thereby reducing an overall diameter of the
adjustable ring.
16. The annuloplasty system of claim 15, and further comprising a
locking mechanism configured to lock the adjustable ring and
thereby prevent further size adjustments to the ring.
17. The annuloplasty system of claim 16, wherein the locking
mechanism is configured to lock a surface of the adjustable ring
between asymmetrical lumens within the locking mechanism.
18. The annuloplasty system of claim 1, wherein the stent is a
self-expanding stent formed of a shape memory material.
19. The annuloplasty system of claim 1, wherein the stent is a
self-expanding NITINOL.TM. framework.
20. The annuloplasty system of claim 1, wherein the system is
configured to be used off-pump to repair the heart valve of a
beating heart.
21. A catheter-based annuloplasty system for use in repairing a
heart valve having a valve annulus, comprising: a delivery catheter
having a proximal end and a distal end; a stent disposed on the
distal end of the catheter; a ring positioned on the stent; and a
plurality of tissue attachment members attached to the ring, the
tissue attachment members shaped for penetration into the valve
annulus and configured to be triggered from a spring-loaded
tensioned state to a relaxed state via movement of the stent.
22. The annuloplasty system of claim 21, wherein each tissue
attachment member comprises: a first prong portion extending from a
first circular spring portion; a second prong portion extending
from a second circular spring portion; a cross-member connecting
the first and second circular spring portions; and wherein the ring
extends through the first and second circular spring portions of
each of the tissue attachment members.
23. A method of repairing a heart valve comprising leaflets and a
valve annulus, the method comprising: delivering a ring having
tissue attachment members to a location adjacent to the heart valve
via a catheter; extending a stent outside of the catheter, thereby
causing the ring to be positioned adjacent to the valve annulus;
and triggering the tissue attachment members via the stent, thereby
causing the ring to be anchored to the valve annulus
24. The method of claim 23, wherein the ring is an adjustable ring
and the stent is a self-expanding stent, and wherein the method
further comprises: contracting the self expanding stent after the
adjustable ring is anchored to the valve annulus, thereby causing a
reduction in size of the adjustable ring and the valve annulus; and
triggering a locking mechanism on the adjustable ring after causing
the reduction in size of the adjustable ring to maintain the
reduced size of the ring.
25. The method of claim 23, wherein the method is performed
off-pump to repair the heart valve of a beating heart.
Description
BACKGROUND
[0001] The present invention relates generally to annuloplasty
prostheses and methods for repair of heart valves. More
particularly, it relates to annuloplasty rings, and related
instruments and procedures, for reconstructing and remodeling a
valve annulus of a patient's heart, for example a mitral valve
annulus.
[0002] Heart valves, such as the mitral, tricuspid, aortic, and
pulmonary valves, are sometimes damaged by disease or by aging,
resulting in problems with the proper functioning of the valve.
Heart valve problems generally take one of two forms: stenosis, in
which a valve does not open completely or the opening is too small,
resulting in restricted blood flow; or insufficiency or
regurgitation, in which blood leaks backward across a valve that
should be closed.
[0003] Annuloplasty prostheses, generally categorized as either
annuloplasty rings or annuloplasty bands, are employed in
conjunction with valvular reconstructive surgery to assist in the
correction of heart valve defects such as stenosis and valvular
insufficiency. There are two atrio-ventricular valves in the heart.
The mitral valve is located on the left side of the heart, and the
tricuspid valve is located on the right side. Anatomically
speaking, each valve type forms or defines a valve annulus and
valve leaflets.
[0004] Both valves can be subjected to or incur damage that
requires the valve in question be repaired or replaced. The effects
of valvular dysfunction vary. For example, mitral regurgitation, a
complication of end-stage cardiomyopathy, has more severe
physiological consequences to the patient as compared to lone
tricuspid valve regurgitation. Regardless, many of the defects are
associated with dilation of the valve annulus. This dilation not
only prevents competence of the valve, but also results in
distortion of the normal shape of the valve orifice. Remodeling of
the annulus is therefore central to most reconstructive procedures
on the mitral and tricuspid valves. In this regard, clinical
experience has shown that repair of the valve, when technically
possible, produces better long-term results as compared to valve
replacement.
[0005] Many procedures have been described to correct the pathology
of the valve leaflets and their associated chordae tendinae and
papillary muscles. For example, with respect to the mitral valve,
two leaflets are present, the anterior leaflet and the posterior
leaflet, such that the mitral valve annulus is commonly described
as having an anterior aspect and a posterior aspect. With this in
mind, in mitral repairs, it is considered important to preserve the
normal distance between the two fibrous trigones. The trigones
essentially straddle the anterior aspect of the annulus. A
significant surgical diminution of the inter-trigonal distance may
cause left ventricular outflow obstruction. Thus, it is desirable
to maintain the natural inter-trigonal distance during and
following mitral valve repair surgery.
[0006] Consequently, when a mitral valve is repaired, the result is
generally a reduction of the size of the posterior aspect of the
mitral valve annulus. As part of the mitral valve repair, the
involved segment of the annulus is diminished (i.e., constricted)
so that the leaflets may coapt correctly on closing, or the annulus
is stabilized to prevent post-operative dilation from occurring,
either as frequently achieved by implantation of a prosthetic ring
or band at the level of the valve annulus in the atrium. The
purpose of the ring or band is to restrict and/or support the
annulus to correct and/or prevent the valvular insufficiency.
However, it is important not to overly restrict the annulus as an
unacceptable valvular stenosis or Systolic Anterior Motion (SAM) of
the anterior leaflet may result. In tricuspid valve repair,
constriction of the annulus usually takes place in a posterior
leaflet segment and in a small portion of the adjacent anterior
leaflet. The septal leaflet segment is not usually required to be
shortened.
[0007] Previously, valve repair or replacement required open-heart
surgery with its attendant risks, expense, and extended recovery
time. Open-heart surgery also requires cardiopulmonary bypass with
risk of thrombosis, stroke, and infarction. More recently, flexible
valve prostheses and various delivery devices have been developed
so that replacement valves can be implanted transvenously using
minimally invasive techniques.
SUMMARY
[0008] One embodiment is directed to a catheter-based annuloplasty
system for use in repairing a heart valve having leaflets and a
valve annulus in a beating heart. The system includes a delivery
catheter having a proximal end and a distal end, and an expandable
stent disposed on the distal end of the catheter. An adjustable
annuloplasty ring is disposed on the expandable stent and is
configured to expand and contract in response to expansion and
contraction of the stent. In one embodiment, the delivery catheter
is configured to deliver the annuloplasty ring to the endocardial
surface of the valve annulus.
[0009] Another embodiment is directed to an annuloplasty prosthesis
for repairing a heart valve having a valve annulus. The
annuloplasty prosthesis includes an adjustable ring comprising a
plurality of interconnected cylindrically-shaped ring segments, and
has a first end co-axially aligned with and inserted into a second
end of the adjustable ring. A plurality of tissue attachment
members is attached to the adjustable ring. The tissue attachment
members are shaped for penetration into the valve annulus and are
configured to be triggered from a tension state to a relaxed
state.
[0010] Yet another embodiment is directed to a method of repairing
a heart valve comprising leaflets and a valve annulus. The method
includes delivering an adjustable ring having tissue attachment
members to a location adjacent to the heart valve via a catheter,
and extending a self-expanding stent outside of the catheter,
thereby causing an expansion of the adjustable ring. The tissue
attachment members are triggered, thereby causing the adjustable
ring to be anchored to the valve annulus. The self-expanding stent
is contracted, thereby causing a reduction in size of the
adjustable ring and the valve annulus. The adjustable ring is
locked into position and the delivery catheter is removed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a cross-sectional schematic view of a heart
showing the location of the heart valves.
[0012] FIG. 2 is a diagram illustrating an annuloplasty system for
use in repairing a heart valve according to one embodiment.
[0013] FIG. 3 is a diagram illustrating one embodiment of the
adjustable ring of the annuloplasty system shown in FIG. 2.
[0014] FIG. 4 is a diagram illustrating the adjustable ring shown
in FIG. 3 in a closed configuration according to one
embodiment.
[0015] FIGS. 5A-5C are diagrams illustrating a locking mechanism of
the adjustable ring shown in FIGS. 3 and 4 according to one
embodiment.
[0016] FIG. 6 is a diagram illustrating a close-up view of a
portion of the adjustable ring shown in FIGS. 3 and 4 in an
expanded state according to one embodiment.
[0017] FIG. 7 is a diagram illustrating a close-up view of a
portion of the adjustable ring shown in FIGS. 3 and 4 in a
compressed state according to one embodiment.
[0018] FIG. 8 is a diagram illustrating a close-up view of a
portion of the adjustable ring shown in FIGS. 3 and 4 while the
ring is in a circular configuration according to one
embodiment.
[0019] FIG. 9 is a diagram illustrating a tissue attachment member
in a relaxed state according to one embodiment.
[0020] FIG. 10 is a diagram illustrating the tissue attachment
member shown in FIG. 9 in a tension state according to one
embodiment.
[0021] FIG. 11 is a diagram illustrating the adjustable ring shown
in FIGS. 3 and 4 including tissue attachment members in a tension
state according to one embodiment.
[0022] FIG. 12 is a diagram illustrating the adjustable ring shown
in FIG. 11 with the tissue attachment members in a relaxed state
according to one embodiment.
[0023] FIG. 13 is a diagram illustrating a tissue attachment
retaining member according to one embodiment.
[0024] FIG. 14 is a flow diagram illustrating a method of repairing
a heart valve according to one embodiment.
DETAILED DESCRIPTION
[0025] The terms "distal" and "proximal" are used herein with
reference to the treating clinician during the use of the catheter
system; "Distal" indicates an apparatus portion distant from, or a
direction away from the clinician and "proximal" indicates an
apparatus portion near to, or a direction towards the clinician.
Additionally, the term "annuloplasty" is used herein to mean
modification/reconstruction of a defective heart valve.
[0026] Embodiments disclosed herein include devices and methods for
treating regurgitation in cardiac valves. While these devices and
methods are described below in terms of being used to treat mitral
regurgitation, it will be apparent to those skilled in the art that
the devices could also be used on other cardiac valves. Embodiments
disclosed herein include minimally-invasive, off-pump,
catheter-based systems and methods for attaching a prosthetic ring
to the annulus of the mitral valve of a beating heart, and
adjusting the ring, thereby reshaping the mitral valve annulus so
that the anterior and posterior leaflets of the mitral valve co-apt
during ventricular contraction.
[0027] FIG. 1 shows a schematic cross-sectional view of a heart 1
having tricuspid valve 2, tricuspid valve annulus 3, mitral valve
4, and mitral valve annulus 5. Mitral valve 4 is a bicuspid valve
having anterior cusp 7 and posterior cusp 6. Anterior cusp 7 and
posterior cusp 6 are often referred to, respectively, as the
anterior and posterior leaflets. FIG. 1 also shows the aorta 15,
which is located adjacent to the wall of the left atrium on the
anterior side of the mitral valve. Also shown in the figure are the
posterior commisure 17 and the anterior commisure 18.
[0028] FIG. 2 is a diagram illustrating a catheter-based
annuloplasty system 200 for use in repairing a heart valve having
leaflets and a valve annulus according to one embodiment. In one
embodiment, annuloplasty system 200 is configured to be used
off-pump to repair the heart valve of a beating heart. Annuloplasty
system 200 includes expandable stent 202, delivery catheter 204,
adjustable annuloplasty ring 206, and a plurality of tissue
attachment retaining members 208. The annuloplasty ring 206
according to one embodiment is particularly adapted to repair one
of the atrio-ventricular valves, such as the mitral valve 4 or the
tricuspid valve 2. The annuloplasty ring 206 illustrated in FIG. 2
is configured for repair of the annulus 5 of the mitral valve 4. It
will be understood that other shapes may be incorporated for other
valve annulus anatomies (e.g., the tricuspid valve annulus 3).
Thus, the present invention is not limited to mitral valve
annuloplasty.
[0029] Stent 202 and catheter 204 comprise a catheter-based
delivery system 210 for delivering ring 206 adjacent to a valve
annulus for attachment thereto. The catheter 204 includes a
proximal end and a distal end. The stent 202 is disposed on the
distal end of the catheter 204. The stent 202 and the ring 206 are
initially collapsed and thereby reduced in diameter, mounted in the
catheter 204, and advanced through the circulatory system of a
patient. The ring 206 is disposed on a distal end of the stent 202,
and is releasably carried within the delivery catheter 204 to a
position near the valve annulus. Stent 202 is then gradually
extended beyond the distal tip of the catheter 204. In the
illustrated embodiment, stent 202 is a self-expanding stent, and
automatically increases in size as it is extended outside of the
catheter 204. Stent 202 and tissue attachment retaining members 208
according to one embodiment are formed of a shape memory material.
In one embodiment, stent 202 comprises a NITINOL.TM. framework.
[0030] In one embodiment, the ring 206 has an adjustable size
(e.g., circumference and diameter), and is configured to be
adjusted via stent 202 during and after installation around the
valve annulus. The ring 206 is configured to expand and contract in
response to expansion and contraction, respectively, of the stent
202. As stent 202 is extended outside of the catheter 204, the
expansion of the distal end of the stent 202 causes a corresponding
expansion in the ring 206. As stent 202 is returned inside of the
catheter 204, the contraction of the distal end of the stent 202
causes a corresponding contraction in the ring 206. Stent 202 is
used to adjust the size of ring 206 until the ring 206 reaches an
appropriate size for attachment to the valve annulus. When the ring
206 reaches the appropriate size, tissue attachment members 900
(FIGS. 9-12) are triggered to attach the ring 206 to the valve
annulus. In one embodiment, the annuloplasty procedure described
herein is performed using three-dimensional echocardiographic
guidance.
[0031] FIG. 3 is a diagram illustrating one embodiment of the
adjustable ring 206 of the annuloplasty system 200 shown in FIG. 2.
The ring 206 is formed from a tube 302 having a channel 310
therethrough. The ring 206 is formed of any medically acceptable
implantable biocompatible material. A first end 304 of the ring
co-axially aligns with and inserts into a second end 306 of the
ring 206 to form the ring shape. In one embodiment, the internal
diameter or tube diameter, d, of selected portions of the ring 206
may be increased in size by axially twisting those portions, as
indicated by arrows 308. The second end 306 is increased in size in
this manner, to allow the first end 304 to fit inside the second
end 306 in a co-axial manner. FIG. 4 is a diagram illustrating the
adjustable ring 206 in a closed configuration according to one
embodiment, after the first end 304 has been inserted inside of the
second end 306. The overall diameter, D, and circumference of the
ring 206 can be decreased by pushing the first end 304 farther into
the second end 306, and can be increased by pulling the first end
304 in an outward direction from the second end 306. In one
embodiment, contracting or collapsing the stent 202 (FIG. 2) causes
the first end 304 to extend farther into the second end 306,
thereby reducing the overall diameter, D, and expanding the stent
202 causes the first end 304 to be pulled back toward the second
end 306, thereby increasing the overall diameter, D.
[0032] FIG. 5A is a diagram illustrating a locking mechanism 502 of
the adjustable ring 206 shown in FIGS. 3 and 4 according to one
embodiment. In the illustrated embodiment, locking mechanism 502 is
a locking sleeve that is positioned at the second end 306 of the
ring 206. Locking mechanism 502 includes an attachment member 504
for attaching a suture or wire (not shown) thereto. Pulling on the
suture attached to the attachment member 504 causes the locking
sleeve 502 to rotate as indicated by arrow 506, which locks the
ring 206 at the current size and prevents further size adjustments
to the ring. The locking mechanism is configured to lock a surface
of the adjustable ring between asymmetrical lumens within the
locking mechanism. FIG. 5B is a diagram illustrating the adjustable
ring 206 in an unlocked state according to one embodiment. As shown
in FIG. 5B, the first end 304 of the ring 206 is positioned inside
of the second end 306 of the ring 206, and the ends 304 and 306 are
axially aligned within the lumen. FIG. 5C is a diagram illustrating
the adjustable ring 206 in a locked state according to one
embodiment. As shown in FIG. 5C, the ends 304 and 306 are no longer
axially aligned within the lumen. The locking mechanism 502
according to one embodiment causes the first end 304 to interfere
with the second end 306 as shown in FIG. 5C, which results in the
ring 206 being held in place at its current size.
[0033] FIG. 6 is a diagram illustrating a close-up view of a
portion of the adjustable ring 206 shown in FIGS. 3 and 4 in an
expanded state according to one embodiment. In the illustrated
embodiment, adjustable ring 206 is formed from a plurality of
interconnected cylindrically-shaped ring segments 602. Each segment
602 includes a plurality of tabs 604 that extend away from the body
of the segment parallel to the surface of the ring 206. Adjacent
tabs 604 in each segment 602 are separated by a gap 606. Each tab
604 of each segment 602 is positioned within one of the gaps 606 of
an adjacent segment 602. The tab design restricts movement axially
to the width of the gap while allowing the ring to bend in any
direction. By performing an axial twisting on the ring 206 in the
direction shown by arrows 308 in FIG. 3 causes a separation between
adjacent segments 602 (as shown in FIG. 6), which causes the
internal diameter, d (FIG. 3), of the ring 206 to increase.
[0034] FIG. 7 is a diagram illustrating a close-up view of a
portion of the adjustable ring 206 shown in FIGS. 3 and 4 in a
compressed state according to one embodiment. When ring 206 is in
an expanded state as shown in FIG. 6, providing a rotational force
to the ring 206 in the opposite direction to that shown by arrows
308 in FIG. 3 causes the separation between adjacent segments 602
to be reduced or eliminated (as shown in FIG. 7), which causes the
internal diameter, d (FIG. 3), of the ring 206 to decrease.
[0035] FIG. 8 is a diagram illustrating a close-up view of a
portion of the adjustable ring 206 shown in FIGS. 3 and 4 while the
ring 206 is in a circular configuration according to one
embodiment. As shown in FIG. 8, when ring 206 is curved into a
circular configuration, such as that shown in FIG. 4, there is a
larger separation between adjacent segments 602 near the outer
radius of the ring 206 (i.e., near the top of FIG. 8), and a
smaller separation between adjacent segments 602 near the inner
radius of the ring 206 (i.e., near the bottom of FIG. 8).
[0036] FIG. 9 is a diagram illustrating a tissue attachment member
900 in a relaxed state according to one embodiment. Tissue
attachment member 900 is shaped for penetration into the valve
annulus and is configured to be triggered from a tension state
(maintained during delivery) to a relaxed state (to attach the ring
206 to the valve annulus). Tissue attachment member 900 includes
first and second prong portions 902A and 902B, first and second
circular spring portions 904A and 904B, and a cross member 906,
which are all formed from NITINOL.TM. wire in one embodiment. The
cross member 906 connects the first and second circular spring
portions 904A and 904B, and includes a feature such as a bump 908
that is configured to be connected to a suture to hold the ring 206
adjacent to the stent 202. The prong portions 902A and 902B extend
from the circular spring portions 904A and 904B, respectively. The
first and second circular spring portions 904A and 904B and
separated by a distance L, which is about two millimeters in one
embodiment. In the illustrated embodiment, tissue attachment member
900 is in a relaxed state.
[0037] FIG. 10 is a diagram illustrating the tissue attachment
member 900 shown in FIG. 9 in a spring-loaded or tension state
according to one embodiment. Tissue attachment member 900 is
changed from the relaxed state (as shown in FIG. 9) to the tension
state (as shown in FIG. 10) by applying a force to move the prong
portions 902A and 902B in the direction indicated by arrows 1002A
and 1002B, respectively, which causes the tissue attachment member
900 to be spring-loaded. If the force is removed from the prong
portions 902A and 902B, the prong portions 902A and 902B spring
back to the relaxed state shown in FIG. 9.
[0038] FIG. 11 is a diagram illustrating the adjustable ring 206
shown in FIGS. 3 and 4 including tissue attachment members 900 in a
spring-loaded or tension state according to one embodiment. As
shown in FIG. 11, ring 206 extends through the circular spring
portions 904A and 904B of each tissue attachment member 900. Thus,
each tissue attachment member 900 is attached to the ring 206 via
the circular spring portions 904A and 904B. A suture 1102 is
attached to the bump 908 of each tissue attachment member 900. The
sutures 1102 are used to hold the ring 206 adjacent to the distal
end of the stent 202 (FIG. 2). In one embodiment, a tissue
attachment retaining member 208 (FIG. 2) is configured to be
positioned over the prong portions 902A and 902B of each tissue
attachment member 900 to hold the tissue attachment member 900 in
the tension state.
[0039] The tissue attachment members 900 are used to attach the
ring 206 to the valve annulus. When ring 206 is in position
adjacent to the annulus, stent 202 is pulled away from ring 206,
which causes tissue attachment retaining members 208 to be lifted
away from prong portions 902A and 902B of the tissue attachment
members 900. When tissue attachment retaining members 208 are
removed from prong portions 902A and 902B, the prong portions 902A
and 902B spring toward the relaxed state (FIG. 12) and penetrate
the annulus tissue.
[0040] FIG. 12 is a diagram illustrating the adjustable ring 206
shown in FIG. 11 with the tissue attachment members 900 in the
relaxed state according to one embodiment. As shown in FIG. 12, the
sutures 1102 have been cut or released, and the tissue attachment
retaining members 208 have been lifted away from the prong portions
902A and 902B, thereby causing the prong portions 902A and 902B to
spring toward the relaxed state, penetrate the annulus tissue, and
anchor the ring 206 to the annulus.
[0041] FIG. 13 is a diagram illustrating a tissue attachment
retaining member 208 according to one embodiment. Retaining member
208 is configured to release the tissue attachment members 900 from
the tension state when the ring 206 is adjacent to the valve
annulus, thereby causing the tissue attachment members 900 to
transition to the relaxed state and anchor the ring 206 to the
valve annulus. As shown in FIG. 13, retaining member 208 slides
over prong portions 902A and 902B of tissue attachment member 900,
and thereby holds the tissue attachment member 900 in the tension
state. Suture 1102 extends through a hole 1302 at the top of the
retaining member 208. Pulling retaining member 208 upward and away
from the prong portions 902A and 902B triggers the tissue
attachment member 900 to transition from the tension state to the
relaxed state. In one embodiment, the ring 206 is configured to be
adjusted in size after the ring 206 has been anchored to the valve
annulus.
[0042] FIG. 14 is a flow diagram illustrating a method 1400 of
repairing a heart valve comprising leaflets and a valve annulus
according to one embodiment. In one embodiment, method 1400 is
performed off-pump to repair the heart valve of a beating heart. At
1402, an adjustable ring 206 having tissue attachment members 900
is delivered to a location adjacent to the heart valve via a
catheter 204. In one embodiment, a distal tip of the catheter 204
containing the adjustable ring 206 and a self-expanding stent 202
is advanced through the vascular system of a patient, passes into
the left atrium, and is positioned adjacent to the mitral valve
annulus. At 1404, the self-expanding stent 202 is extended outside
of the catheter 204, thereby causing an expansion of the adjustable
ring 206, and causing the adjustable ring 206 to be positioned
against the mitral valve annulus. At 1406, tissue attachment
members 900 attached to the adjustable ring 206 are triggered,
thereby causing the adjustable ring 206 to be anchored to the
mitral valve annulus. At 1408, the self-expanding stent 202 is
partially contracted, which causes a reduction in size of the
adjustable ring 206 and the valve annulus. In one embodiment, the
stent 202 is contracted by pushing the catheter forward, causing a
portion of the stent 202 to return inside of the catheter 204.
Because the ring 206 is securely fastened to the annulus of the
mitral valve via the tissue attachment members 900, the diameter
and circumference of the annulus is reduced as the size of the ring
206 is reduced at 1408. In one embodiment, the size of the annulus
is reduced at 1408 sufficiently so that anterior and posterior
leaflets close during ventricular contraction, and regurgitation of
blood is reduced. At 1410, a locking mechanism 502 on the ring 206
is triggered after causing the reduction in size of the ring 206 to
maintain the reduced size of the ring 206. At 1412, sutures 1102
connecting the ring 206 to the stent 202 are released. At 1414, the
delivery catheter 204 including the stent 202 is withdrawn from the
body of the patient.
[0043] The minimally-invasive, off-pump, catheter-based
annuloplasty system and method described herein provides the
ability to intervene with patients in both early disease states or
in advanced heart failure, and provides advantages over traditional
surgical repair devices because traditional open heart surgery is
no longer needed.
[0044] Although the present disclosure has been described with
reference to preferred embodiments, workers skilled in the art will
recognize that changes can be made in form and detail without
departing from the spirit and scope of the present disclosure.
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