U.S. patent application number 12/769593 was filed with the patent office on 2010-12-09 for apparatus and method for replacing a diseased cardiac valve.
This patent application is currently assigned to The Cleveland Clinic Foundation. Invention is credited to Ji-Feng Chen, Jose Luis Navia, Qun Zhou.
Application Number | 20100312333 12/769593 |
Document ID | / |
Family ID | 42299145 |
Filed Date | 2010-12-09 |
United States Patent
Application |
20100312333 |
Kind Code |
A1 |
Navia; Jose Luis ; et
al. |
December 9, 2010 |
APPARATUS AND METHOD FOR REPLACING A DISEASED CARDIAC VALVE
Abstract
An apparatus is provided for replacing a native cardiac valve.
The native cardiac valve has at least one leaflet and is surrounded
by a native cardiac valve annulus having superior and inferior
aspects. The apparatus comprises a barbell-shaped, expandable
anchoring member including first, second, and main body portions
extending between the end portions. The main body portion includes
a channel defined by inner and outer surfaces. Each of the first
and second end portions has a diameter greater than the diameter of
the main body portion. The first and second end portions are sized
to respectively contact the superior and inferior aspects of the
native cardiac valve annulus when the expandable anchoring member
is in an expanded configuration. The apparatus also includes an
expandable support member operably disposed within the main body
portion of the expandable anchoring member, and a prosthetic
cardiac valve secured within the expandable support member.
Inventors: |
Navia; Jose Luis; (Shaker
Heights, OH) ; Chen; Ji-Feng; (Lakewood, OH) ;
Zhou; Qun; (Lakewood, OH) |
Correspondence
Address: |
TAROLLI, SUNDHEIM, COVELL & TUMMINO L.L.P.
1300 EAST NINTH STREET, SUITE 1700
CLEVELAND
OH
44114
US
|
Assignee: |
The Cleveland Clinic
Foundation
|
Family ID: |
42299145 |
Appl. No.: |
12/769593 |
Filed: |
April 28, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61173782 |
Apr 29, 2009 |
|
|
|
Current U.S.
Class: |
623/2.36 |
Current CPC
Class: |
A61F 2/2436 20130101;
A61F 2220/0008 20130101; A61F 2/2418 20130101; A61F 2250/006
20130101; A61F 2220/0066 20130101; A61F 2230/0078 20130101; A61F
2220/005 20130101; A61F 2230/0054 20130101 |
Class at
Publication: |
623/2.36 |
International
Class: |
A61F 2/24 20060101
A61F002/24 |
Claims
1. An apparatus for replacing a native cardiac valve, the native
cardiac valve having at least one leaflet and being surrounded by a
native cardiac valve annulus, the native cardiac valve annulus
having a superior aspect and an inferior aspect, said apparatus
comprising: a barbell-shaped expandable anchoring member including
a first end portion, a second end portion, and a main body portion
extending between said end portions, said main body portion
including a channel defined by an inner surface and an outer
surface, each of said first and second end portions having a
diameter greater than the diameter of said main body portion, said
first and second end portions being sized to respectively contact
the superior and inferior aspects of the native cardiac valve
annulus when said expandable anchoring member is in an expanded
configuration; an expandable support member operably disposed
within said main body portion of said expandable anchoring member;
and a prosthetic cardiac valve secured within said expandable
support member.
2. The apparatus of claim 1, wherein said expandable anchoring
member is comprised of a single strand of a flexibly resilient
material.
3. The apparatus of claim 1, wherein each of said first and second
end portions has a hemi-spherical shape with respect to an axial
plane of the said main body portion of said expandable anchoring
member.
4. The apparatus of claim 1, wherein each of said first and second
end portions has a bulbous shape with respect to an axial plane of
the said main body portion of said expandable anchoring member.
5. A method for replacing a native cardiac valve, the native
cardiac valve having at least one leaflet and being surrounded by a
native cardiac valve annulus, the native cardiac valve annulus
having a superior aspect and an inferior aspect, said method
comprising the steps of: providing an apparatus comprising a
barbell-shaped expandable anchoring member, an expandable support
member, and a prosthetic cardiac valve secured within the
expandable support member, the expandable support member being
secured within the expandable anchoring member, each of the first
and second end portions having a diameter greater than the diameter
of the main body portion; placing the apparatus into a delivery
catheter; inserting the delivery catheter into an atrial chamber;
advancing the delivery catheter until the delivery catheter is
positioned within the native cardiac valve annulus; and removing
the apparatus from the delivery catheter so that the expandable
anchoring member obtains an expanded configuration and the first
and second end portions of the expandable anchoring member
respectively contact the superior and inferior aspects of the
native cardiac valve annulus and thereby secure the expandable
anchoring member in the native cardiac annulus.
6. An apparatus for replacing a native cardiac valve, the native
cardiac valve having at least one leaflet and being surrounded by a
native cardiac valve annulus, the native cardiac valve annulus
having a superior aspect and an inferior aspect, said apparatus
comprising: an expandable support member; a prosthetic cardiac
valve operably secured within said expandable support member; and a
securing member operably connected to said expandable support
member, said securing member comprising an elongated body member
having a first end, a second end, and a main body portion extending
between said first and second ends, said second end including a
first attachment member operably connected thereto for contacting
the inferior aspect of the native cardiac valve annulus when said
expandable support member is in an expanded configuration.
7. The apparatus of claim 6, wherein said first attachment member
includes at least one rod-shaped puncturing member for embedding
into the tissue of the native cardiac valve annulus when said
expandable support member is in an expanded configuration.
8. The apparatus of claim 6, wherein said first end of said
securing member includes a second attachment member operably
connected thereto for contacting the superior aspect of the native
cardiac valve annulus when said expandable support member is in an
expanded configuration.
9. The apparatus of claim 8, wherein each of said first and second
attachment members has a loop-shaped configuration that extends
substantially axial to said elongated body member of said securing
member when said expandable support member is in an expanded
configuration.
10. The apparatus of claim 8, wherein each of said first and second
attachment members comprises a flexible, rod-shaped member that
extends substantially axial to said elongated body member of said
securing member when said expandable support member is in an
expanded configuration.
11. The apparatus of claim 8, wherein each of said first and second
attachment members comprises a windable coil that extends
substantially axial to said elongated body member of said securing
member when said expandable support member is in an expanded
configuration.
12. The apparatus of claim 8, wherein said first attachment member
comprises an anchoring ring and said second attachment member
comprises a windable coil, said anchoring ring and said windable
coil extending substantially axial to said elongated body member of
said securing member when said expandable support member is in an
expanded configuration.
13. The apparatus of claim 8, wherein said first attachment member
comprises a flexible, rod-shaped member and said second attachment
member comprises a windable coil, said rod-shaped member and said
windable coil extending substantially axial to said elongated body
member of said securing member when said expandable support member
is in an expanded configuration.
14. The apparatus of claim 6, wherein a layer of biocompatible
material is connected to a portion of said elongated body member of
said securing member to prevent or mitigate leakage of blood flow
between said expandable support member and the native cardiac valve
annulus.
15. A method for replacing a native cardiac valve, the native
cardiac valve having at least one leaflet and being surrounded by a
native cardiac valve annulus, the native cardiac valve annulus
having a superior aspect and an inferior aspect, said method
comprising the steps of: providing an apparatus comprising an
expandable support member having a prosthetic cardiac valve secured
therein and a securing member operably connected to the expandable
support member, the securing member comprising an elongated body
member having a first end, a second end, and a main body portion
extending between the first and second ends, the second end
including a first attachment member operably connected thereto;
placing the expandable anchoring member into a delivery catheter;
inserting the apparatus into an atrial chamber; advancing the
delivery catheter until the delivery catheter is positioned within
the native cardiac valve annulus; and removing the apparatus from
the delivery catheter so that the expandable support member obtains
an expanded configuration and the first attachment member of the
securing member contacts the inferior aspect of the native cardiac
valve annulus and thereby secures the expandable support member in
the native cardiac valve annulus.
16. An apparatus for replacing a native cardiac valve, the native
cardiac valve having at least one leaflet and being surrounded by a
native cardiac valve annulus, the native cardiac valve annulus
having a superior aspect and an inferior aspect, said apparatus
comprising: a securing member comprising an elongated body member
having a first end, a second end, and a main body portion extending
between said first and second ends, said second end including a
first attachment member operably connected thereto for contacting
the inferior aspect of the native cardiac valve annulus when said
expandable support member is in an expanded configuration; and a
prosthetic valve operably secured to said securing member.
17. The apparatus of claim 16, wherein said first attachment member
includes at least one rod-shaped puncturing member for embedding
into the tissue of the native cardiac valve annulus when said
expandable support member is in an expanded configuration.
18. The apparatus of claim 16, wherein said first end of said
securing member includes a second attachment member operably
connected thereto for contacting the superior aspect of the native
cardiac valve annulus when said expandable support member is in an
expanded configuration.
19. The apparatus of claim 18, wherein each of said first and
second attachment members has a loop-shaped configuration that
extends substantially axial to said elongated body member of said
securing member when said expandable support member is in an
expanded configuration.
20. The apparatus of claim 18, wherein each of said first and
second attachment members comprises a flexible, rod-shaped member
that extends substantially axial to said elongated body member of
said securing member when said expandable support member is in an
expanded configuration.
21. The apparatus of claim 18, wherein each of said first and
second attachment members comprises a windable coil that extends
substantially axial to said elongated body member of said securing
member when said expandable support member is in an expanded
configuration.
22. The apparatus of claim 18, wherein said first attachment member
comprises an anchoring ring and said second attachment member
comprises a windable coil, said anchoring ring and said windable
coil extending substantially axial to said elongated body member of
said securing member when said expandable support member is in an
expanded configuration.
23. The apparatus of claim 18, wherein said first attachment member
comprises a flexible, rod-shaped member and said second attachment
member comprises a windable coil, said rod-shaped member and said
windable coil extending substantially axial to said elongated body
member of said securing member when said expandable support member
is in an expanded configuration.
24. The apparatus of claim 16, wherein a layer of biocompatible
material is connected to a portion of said elongated body member of
said securing member to prevent or mitigate leakage of blood flow
between said expandable support member and the native cardiac valve
annulus.
25. A method for replacing a native cardiac valve, the native
cardiac valve having at least one leaflet and being surrounded by a
native cardiac valve annulus, the native cardiac valve annulus
having a superior aspect and an inferior aspect, said method
comprising the steps of: providing an apparatus comprising a
securing member and a prosthetic cardiac valve operably connected
to the securing member, the securing member comprising an elongated
body member having a first end, a second end, and a main body
portion extending between the first and second ends, the second end
including a first attachment member operably connected thereto for
contacting the inferior aspect of the native cardiac valve annulus
when the expandable support member is in an expanded configuration;
placing the apparatus into a delivery catheter; inserting the
delivery catheter into an atrial chamber; advancing the delivery
catheter until the delivery catheter is positioned within the
native cardiac valve annulus; and removing the apparatus from the
delivery catheter so that the prosthetic cardiac valve expands in
place of the native cardiac valve and the first attachment member
of the securing member contacts the inferior aspect of the native
cardiac valve annulus and thereby secures the prosthetic cardiac
valve in the native cardiac valve annulus.
Description
RELATED APPLICATION
[0001] This application claims priority from U.S. Provisional
Application No. 61/173,782, filed Apr. 29, 2009, the subject matter
of which is incorporated herein by reference.
TECHNICAL FIELD
[0002] The present invention relates generally to apparatus and
methods for treating heart disease, and more particularly to
self-expandable apparatus and methods for treating diseased cardiac
valves.
BACKGROUND OF THE INVENTION
[0003] There are two atrioventricular (AV) valves in the heart; one
on the left side of the heart and one on the right side of the
heart. The left side AV valve is the mitral valve and the right
side AV valve is the tricuspid valve. Both of these valves are
subject damage and dysfunction that requires that the valve be
repaired or replaced.
[0004] The mitral and tricuspid valves differ significantly in
anatomy. While the annulus of the mitral valve is generally
D-shaped, the annulus of the tricuspid valve is more circular. The
effects of valvular dysfunction vary between the mitral valve and
the tricuspid valve. Mitral valve regurgitation has more severe
physiological consequences to the patient than does tricuspid valve
regurgitation, a small amount of which is tolerable.
[0005] In mitral valve insufficiency, the valve leaflets do not
fully close and a certain amount of blood leaks back into the left
atrium when the left ventricle contracts. As a result, the heart
has to work harder by pumping not only the regular volume of blood,
but also the extra volume of blood that regurgitated back into the
left atrium. The added workload creates an undue strain on the left
ventricle. This strain can eventually wear out the heart and result
in morbidity. Consequently, proper function of the mitral valve is
critical to the pumping efficiency of the heart.
[0006] Mitral and tricuspid valve disease is traditionally treated
by either surgical repair with an annuloplasty ring or surgical
replacement with a valve prosthesis. Surgical valve replacement or
repair, however, is often an exacting operation. The operation
requires the use of a heart-lung machine for external circulation
of the blood as the heart is stopped and then opened during the
surgical intervention. Once the heart is opened, the artificial
cardiac valves and/or annuloplasty rings are sewed in under direct
vision.
[0007] Surgical repair of the AV valves exposes patients (i.e.,
elderly patients) to many risks. A minimally invasive procedure
that could be performed under local anesthesia in the cardiac
catheterization lab, rather than in cardiac surgery, could
therefore offer tremendous benefits to these patients.
Consequently, an apparatus for replacing a diseased AV valve using
a minimally invasive approach would be very helpful in providing
additional opportunities to treat patients with valvular
insufficiency and/or end stage heart failure.
SUMMARY OF THE INVENTION
[0008] According to one aspect of the present invention, an
apparatus is provided for replacing a native cardiac valve. The
native cardiac valve has at least one leaflet and is surrounded by
a native cardiac valve annulus. The native cardiac valve annulus
has a superior aspect and an inferior aspect. The apparatus
comprises a barbell-shaped, expandable anchoring member including a
first end portion, a second end portion, and a main body portion
extending between the end portions. The main body portion includes
a channel defined by an inner surface and an outer surface. Each of
the first and second end portions has a diameter greater than the
diameter of the main body portion. The first and second end
portions are sized to respectively contact the superior and
inferior aspects of the native cardiac valve annulus when the
expandable anchoring member is in an expanded configuration. The
apparatus also includes an expandable support member operably
disposed within the main body portion of the expandable anchoring
member, and a prosthetic cardiac valve secured within the
expandable support member.
[0009] According to another aspect of the present invention, a
method is provided for replacing a native cardiac valve. The native
cardiac valve has at least one leaflet and is surrounded by a
native cardiac valve annulus. The native cardiac valve annulus has
a superior aspect and an inferior aspect. One step of the method
comprises providing an apparatus including a barbell-shaped
expandable anchoring member, an expandable support member, and a
prosthetic cardiac valve secured within the expandable support
member. The expandable support member is secured within the
expandable anchoring member. Each of the first and second end
portions has a diameter greater than the diameter of the main body
portion. The apparatus is placed into a delivery catheter, and the
delivery catheter inserted into an atrial chamber. The delivery
catheter is advanced until the delivery catheter is positioned
within the native cardiac valve annulus. Next, the apparatus is
removed from the delivery catheter so that the expandable anchoring
member obtains an expanded configuration and the first and second
end portions of the expandable anchoring member respectively
contact the superior and inferior aspects of the native cardiac
valve annulus and thereby secure the expandable anchoring member in
the native cardiac annulus.
[0010] According to another aspect of the present invention, an
apparatus is provided for replacing a native cardiac valve. The
native cardiac valve has at least one leaflet and is surrounded by
a native cardiac valve annulus. The native cardiac valve annulus
has a superior aspect and an inferior aspect. The apparatus
comprises an expandable support member, a prosthetic cardiac valve
operably secured within the expandable support member, and a
securing member operably connected to the expandable support
member. The securing member comprises an elongated body member
having a first end, a second end, and a main body portion extending
between the first and second ends. The second end includes a first
attachment member operably connected thereto for contacting the
inferior aspect of the native cardiac valve annulus when the
expandable support member is in an expanded configuration.
[0011] According to another aspect of the present invention, a
method is provided for replacing a native cardiac valve. The native
cardiac valve has at least one leaflet and is surrounded by a
native cardiac valve annulus. The native cardiac valve annulus has
a superior aspect and an inferior aspect. One step of the method
comprises providing an apparatus including an expandable support
member having a prosthetic cardiac valve secured therein and a
securing member operably connected to the expandable support
member. The securing member comprises an elongated body member
having a first end, a second end, and a main body portion extending
between the first and second ends. The second end includes a first
attachment member operably connected thereto. The expandable
anchoring member is placed into a delivery catheter, and the
delivery catheter is then inserted into an atrial chamber. The
delivery catheter is advanced until the delivery catheter is
positioned within the native cardiac valve annulus. Next, the
apparatus is removed from the delivery catheter so that the
expandable support member obtains an expanded configuration and the
first attachment member of the securing member contacts the
inferior aspect of the native cardiac valve annulus and thereby
secures the expandable support member in the native cardiac valve
annulus.
[0012] According to another aspect of the present invention, an
apparatus is provided for replacing a native cardiac valve. The
native cardiac valve has at least one leaflet and is surrounded by
a native cardiac valve annulus. The native cardiac valve annulus
has a superior aspect and an inferior aspect. The apparatus
comprises a securing member including an elongated body member
having a first end, a second end, and a main body portion extending
between the first and second ends. The second end includes a first
attachment member operably connected thereto for contacting the
inferior aspect of the native cardiac valve annulus when the
expandable support member is in an expanded configuration. The
apparatus also comprises a prosthetic valve operably secured to the
securing member.
[0013] According to another aspect of the present invention, a
method is provided for replacing a native cardiac valve. The native
cardiac valve has at least one leaflet and is surrounded by a
native cardiac valve annulus. The native cardiac valve annulus has
a superior aspect and an inferior aspect. One step of the method
includes providing an apparatus comprising a securing member and a
prosthetic cardiac valve operably connected to the securing member.
The securing member comprises an elongated body member having a
first end, a second end, and a main body portion extending between
the first and second ends. The second end includes a first
attachment member operably connected thereto for contacting the
inferior aspect of the native cardiac valve annulus when the
expandable support member is in an expanded configuration. The
apparatus is placed into a delivery catheter, and the delivery
catheter is then inserted into an atrial chamber. The delivery
catheter is advanced until the delivery catheter is positioned
within the native cardiac valve annulus. Next, the apparatus is
removed from the delivery catheter so that the prosthetic cardiac
valve expands in place of the native cardiac valve and the first
attachment member of the securing member contacts the inferior
aspect of the native cardiac valve annulus and thereby secures the
prosthetic cardiac valve in the native cardiac valve annulus.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The foregoing and other features of the present invention
will become apparent to those skilled in the art to which the
present invention relates upon reading the following description
with reference to the accompanying drawings, in which:
[0015] FIG. 1A is a perspective view of an expandable anchoring
member constructed in accordance with the present invention;
[0016] FIG. 1B is a perspective view of a prosthetic valve operably
secured to an expandable support member;
[0017] FIG. 10 is a perspective view of an apparatus for replacing
a native cardiac valve constructed in accordance with the present
invention;
[0018] FIG. 1D is a cross-sectional view of the apparatus shown in
FIG. 10;
[0019] FIG. 1E is a top plan view of the apparatus shown in FIG.
10;
[0020] FIG. 2 is a cross-sectional view of a human heart;
[0021] FIG. 3A is a perspective view showing an alternative
embodiment of the expandable anchoring member in FIG. 1A;
[0022] FIG. 3B is a perspective view showing an alternative
embodiment of the apparatus in FIG. 10;
[0023] FIG. 4 is a perspective view showing the apparatus of FIG.
10 being delivered to a native mitral valve;
[0024] FIG. 5 is a cross-sectional view showing the apparatus of
FIG. 10 implanted in a native mitral valve;
[0025] FIG. 6A is a cross-sectional view showing another
alternative embodiment of the apparatus in FIG. 10;
[0026] FIG. 6B is a cross-sectional view showing an alternative
embodiment of the apparatus in FIG. 6A;
[0027] FIG. 6C is a cross-sectional view showing another
alternative embodiment of the apparatus in FIG. 6A;
[0028] FIG. 6D is a cross-sectional view showing another
alternative embodiment of the apparatus in FIG. 6A;
[0029] FIG. 6E is a cross-sectional view showing another
alternative embodiment of the apparatus in FIG. 6A;
[0030] FIG. 7 is a perspective view showing the apparatus of FIG.
6A being delivered to a native mitral valve;
[0031] FIG. 8 is a cross-sectional view showing the apparatus of
FIG. 6A implanted in a native mitral valve;
[0032] FIG. 9 is a cross-sectional view showing another alternative
embodiment of the apparatus in FIG. 6A;
[0033] FIG. 10 is a cross-sectional view showing the apparatus of
FIG. 9 implanted in a native mitral valve;
[0034] FIG. 11 is a cross-sectional view showing another
alternative embodiment of the apparatus in FIG. 6A; and
[0035] FIG. 12 is a cross-sectional view showing the apparatus of
FIG. 11 implanted in a native mitral valve.
DETAILED DESCRIPTION
[0036] The present invention relates generally to apparatus and
methods for treating heart disease, and more particularly to
self-expandable apparatus and methods for treating diseased cardiac
valves. As representative of the present invention, FIGS. 1A-E
illustrate one embodiment of an apparatus 10 for replacing a native
cardiac valve. Although the present invention is described herein
as being useful for treating a diseased mitral valve, it should be
appreciated that other cardiac valves, such as the tricuspid valve,
the pulmonary valve, and the aortic valve are also treatable
according to the present invention.
[0037] FIG. 2 shows a human heart 12. The human heart 12 contains
four chambers: the right and left atria 14 and 16 and the right and
left ventricles 18 and 20. The thin-walled right atrium 14 receives
deoxygenated blood from the superior vena cava 22, the inferior
vena cava (not shown), and from the coronary sinus (not shown). The
thin-walled left atrium 16 receives oxygenated blood from pulmonary
veins 24. The right and left ventricles 18 and 20 pump oxygenated
and deoxygenated blood, respectively, throughout the body, and the
pocket-like pulmonary (not shown) and aortic 26 semilunar valves
prevent reflux into the ventricles.
[0038] Atrial blood is pumped through the atrioventricular
orifices, guarded by the 3-cusp tricuspid valve 28 on the right and
the 2-cusp mitral valve 30 on the left. The mitral valve 30 is
formed by two leaflets; namely, the anterior leaflet 32 and the
posterior leaflet 34. The anterior leaflet 32 extends along a
generally planar base of a D-shaped mitral annulus 36 (FIG. 5),
while the posterior leaflet 34 (FIG. 2) extends arcuately around
the curved portion of the annulus. The mitral and tricuspid valves
28 and 30 are secured to the papillary muscles 38 in the right and
left ventricles 18 and 20 by tendinous chordae tendineae 40, and by
the mitral annulus 36 and the tricuspid annulus (not shown in
detail).
[0039] Referring again to FIGS. 1A-E, one embodiment of the present
invention includes an apparatus 10 for replacing a native cardiac
valve, such as a native mitral valve 30. As shown in FIG. 1A, the
apparatus 10 comprises a barbell-shaped expandable anchoring member
42. The expandable anchoring member 42 includes a first end portion
44, a second end portion 46, and a main body portion 48 extending
between the first and second end portions. The main body portion 48
includes a channel 50 defined by an inner surface 52 and an outer
surface 54. The main body portion 48 has a generally cylindrical
shape and is adapted to conform to the three-dimensional shape of a
native cardiac valve annulus. It will be appreciated that the size
and shape of the main body portion 48 may be varied as needed. For
example, the diameter, circumference, and/or length of the main
body portion 48 may be varied so that the expandable anchoring
member 42 more readily conforms to the shape of a native cardiac
valve annulus.
[0040] Each of the first and second end portions 44 and 46 of the
expandable anchoring member 42 has a diameter that is greater than
the diameter of the main body portion 48. As described in more
detail below, the first and second end portions 44 and 46 are sized
to respectively contact the superior and inferior aspects of a
native cardiac valve annulus when the expandable anchoring member
42 is in an expanded configuration. The first and second end
portions 44 and 46 can have identical or different configurations.
As shown in FIG. 1A, for example, the first and second end portions
44 and 46 have a hemi-spherical shape with respect to an axial
plane AP of the main body portion 48. Alternatively, the first and
second end portions 44 and 46 of the expandable anchoring member 42
can have bulbous shape (FIGS. 3A-B).
[0041] The expandable anchoring member 42 is comprised of a single
strand of a flexibly resilient material, such as Nitinol, stainless
steel, or other suitable medical grade metals or plastics having
shape memory characteristics. It will be appreciated, however, that
the expandable anchoring member 42 can alternatively be comprised
of multiple strands. Additionally, at least a portion of the
expandable anchoring member 42 may be made from a bioabsorbable
material including, for example, magnesium alloy, dendrimers,
biopolymers such as thermoplastic starch, polyalctides, cellulose,
and aliphatic aromatic copolyesters. The expandable anchoring
member 42 may also be made of a radio-opaque material or include
radio-opaque markers (not shown) to facilitate fluoroscopic
visualization. The flexible and expandable properties of the
expandable anchoring member 42 facilitate delivery of the apparatus
10 to a diseased native cardiac valve.
[0042] The apparatus 10 (FIG. 1C) additionally includes an
expandable support member 56 (FIG. 1B) operably disposed within the
main body portion 48 of the expandable anchoring member 42. The
expandable support member 56 can be secured within the main body
portion 48 using any one or combination of known fastening means
(not shown), such as sutures, clips, pins, staples, adhesives, or
the like. As shown in FIG. 1B, the expandable support member 56
includes oppositely disposed proximal and distal end portions 58
and 60, and a main body portion 62 extending between the end
portions. The expandable support member 56 is both flexible and
resilient and, as discussed in more detail below, can be made of a
shape memory material such as Nitinol, stainless steel, or other
suitable medical grade metals or plastics having shape memory
characteristics.
[0043] The expandable support member 56 may additionally or
optionally be made from a bioabsorbable material including, for
example, magnesium alloy, dendrimers, biopolymers such as
thermoplastic starch, polyalctides, cellulose, and aliphatic
aromatic copolyesters. The expandable support member 56 may also be
made of a radio-opaque material or include radio-opaque markers to
facilitate fluoroscopic visualization. The flexible and expandable
properties of the expandable support member 56 facilitate placement
and movement of the expandable support member within the main body
portion 48 of the expandable anchoring member 42.
[0044] The expandable support member 56 comprises a continuous
series of W-shaped segments which collectively form a mesh-like
configuration. It is contemplated, however, that other geometries
may be used. The lower tips 64, as viewed in FIG. 1B, of the
W-shaped segments form the distal end portion 60 of the expandable
support member 56, and the upper tips 66 of the W-shaped segments
form the proximal end portion 58 of the expandable support member.
Other examples of expandable support members 56 which may be used
as part of the present invention are disclosed in U.S. Patent Pub.
No. 2007/0255389 A1, the entirety of which is hereby incorporated
by reference.
[0045] As shown in FIGS. 1B-E, the expandable support member 56
also includes a prosthetic valve 68 operably secured therein. The
prosthetic valve 68 is secured to the expandable support member 56
using any one or combination of known fastening means (not shown),
such as sutures, pins, clips, staples, adhesives, or the like.
Examples of prosthetic valves 68 are known in the art and can
include, for instance, the prosthetic valves disclosed in U.S. Pat.
No. 5,156,621, which is hereby incorporated by reference in its
entirety.
[0046] The prosthetic valve 68 may be fixed and preserved using a
variety of known methods. The use of chemical processes for the
fixation and preservation of biological tissues have been described
and are readily available in the art. For example, glutaraldehyde
and other related aldehydes have seen widespread use in preparing
cross-linked biological tissues. Glutaraldehyde is a five carbon
aliphatic molecule with an aldehyde at each end of the chain,
rendering it bifunctional. These aldehyde groups react under
physiological conditions with primary amine groups on collagen
molecules resulting in the cross-linking of collagen containing
tissues. Methods for glutaraldehyde fixation of biological tissues
have been extensively described and are well known in the art. In
general, a biological tissue sample to be cross-linked is simply
contacted with a glutaraldeyde solution for a duration effective to
cause the desired degree of cross-linking within the biological
tissue being treated.
[0047] Many variations and conditions have been applied to optimize
glutaraldehyde fixation procedures. For example, lower
concentrations have been found to be better in bulk tissue
cross-linking compared to higher concentrations. It has been
proposed that higher concentrations of glutaraldehyde may promote
rapid surface cross-linking of the tissue, generating a barrier
that impedes or prevents the further diffusion of glutaraldehdye
into the tissue bulk. For most bioprosthesis applications, however,
the tissue is treated with a relatively low concentration
glutaraldehyde solution, e.g., typically between 0.1%-5%, for 24
hours or more to ensure optimum fixation. Various other
combinations of glutaraldehyde concentrations and treatment times
will also be suitable depending on the objectives for a given
application. Examples of such other combinations include, but are
not limited to, those disclosed in U.S. Pat. Nos. 6,547,827,
6,561,970, and 6,878,168, all of which are hereby incorporated by
reference in their entireties.
[0048] In addition to bifunctional aldehydes, many other chemical
fixation procedures have been described. For example, some methods
have employed polyethers, polyepoxy compounds, diisocyanates, and
azides. These and other approaches are available to the skilled
artisan for treating biological tissues, and are suitable for
cross-linking vascular graft tissue according to the present
invention.
[0049] The prosthetic valve 68 may also be treated and preserved
with a dry tissue valve procedure as described in U.S. Pat. No.
6,534,004, the entire contents of which are hereby incorporated by
reference. Furthermore, the prosthetic valve 68 may be treated with
anti-calcification solutions, such as XenoLogiX.RTM. treatment
(Edwards Lifesciences, Irvine, Calif.), the SynerGraf.RTM.
(CryoLife, Inc., Kennesaw, Ga.) treatment process, and/or
anti-calcification agents, such as a-amino oleic acid.
[0050] The apparatus 10 may further include a layer (not shown) of
biocompatible material covering at least a portion of the
expandable anchoring member. The layer of biocompatible material
may be synthetic, such as Dacron.RTM. (Invista, Wichita, Kans.),
woven velour, polyurethane, polytetrafluoroethylene (PTFE),
expanded PTFE, Gore-Tex.RTM. (W. L. Gore & Associates,
Flagstaff, Ariz.), or heparin-coated fabric. Alternatively, the
layer may be a biological material, such as bovine or equine
pericardium, peritoneal tissue, an allograft, a homograft, a
patient graft, or a cell-seeded tissue. The layer can cover either
the inner surface 52 of the expandable anchoring member 42, the
outer surface 54 of the expandable anchoring member, or a
combination thereof. The layer may be attached around the entire
circumference of the expandable anchoring member 42 or,
alternatively, may be attached in pieces or interrupted sections to
allow the expandable anchoring member to more easily expand and
contract. By covering a portion of the expandable anchoring member
42 with a layer of biocompatible material, the hemocompatibility of
the apparatus 10 may be improved.
[0051] At least a portion of the apparatus 10 may be treated with a
therapeutic agent for eluting into cardiac tissue and/or blood. The
therapeutic agent may be capable of treating a variety of
pathological conditions including, but not limited to, thrombosis,
stenosis and inflammation. Accordingly, the therapeutic agent may
include at least one of an anticoagulant, an antioxidant, a
fibrinolytic, a steroid, an anti-apoptotic agent, an
anti-inflammatory agent, a receptor agonist or antagonist, and/or a
hormone.
[0052] Optionally or additionally, the therapeutic agent may be
capable of treating or preventing other diseases or disease
processes, such as microbial infections. In these instances, the
therapeutic agent may include an anti-microbial agent and/or a
biological agent such as a cell, peptide or nucleic acid. The
therapeutic agent can be simply linked to a surface of the
apparatus 10, embedded and released from within polymer materials,
such as a polymer matrix, or surrounded by and released through a
carrier. The entire apparatus 10, or only a portion thereof, may be
treated with the therapeutic agent. Additionally, different
portions of the apparatus 10 may be treated with different
therapeutic agents.
[0053] The apparatus 10 shown in FIGS. 1A-E and FIGS. 3A-B can be
used to replace a diseased mitral valve 30, for example, using any
one or combination of known surgical methods. As shown in FIGS.
4-5, for example, an apical puncture method can be used to
respectively deliver the apparatus 10 shown in FIG. 10. It will be
appreciated, however, that other percutaneous, transvascular,
and/or open surgical procedures may be used to deliver the
apparatus 10 to a diseased cardiac valve. For example, the
apparatus 10 can be delivered to the tricuspid valve 28 via the
pulmonary artery (not shown) or to the mitral valve 30 via the
aortic valve 26. It will also be appreciated that the method of the
present invention will typically entail gaining access to a beating
heart 12; however, the present invention may also be used for
intravascular stopped-heart access as well as stopped-heart open
chest procedures.
[0054] FIG. 4 illustrates one step of an apical puncture method for
delivering the apparatus 10 shown in FIG. 1C to a native cardiac
valve, such as the mitral valve 30. One step of the method includes
placing the apparatus 10 into a delivery catheter 70. As shown in
FIG. 4, the delivery catheter 70 has proximal end portion 72 and a
distal end portion 74. The delivery catheter 70 is shaped to
facilitate insertion and removal of the apparatus 10 into and out
of a puncture tool 76 (not shown in detail). The delivery catheter
70 may be constructed from a rigid, semi-rigid, or flexible
material. For example, the delivery catheter 70 may be made of a
flexible elastic material, such as a shape memory alloy, a
super-elastic material (e.g., Nitinol, spring stainless steel,
etc.), or plastic. Alternatively, the delivery catheter 70 may be
made of a rigid material, such as hardened plastic, silicon,
polyurethane, or the like.
[0055] Prior to placing the apparatus 10 into the delivery catheter
70, the dimensions of the native mitral valve 30 and the native
mitral annulus 36 are determined. Various methods and devices for
determining the dimensions of cardiac valves and cardiac valve
annuluses are known in the art and include, for example,
echocardiogram, computed tomography, magnetic resonance imaging,
fluoroscopy, and angiography. After determining the dimensions of
the native mitral valve 30 and the native mitral annulus 36, an
appropriately-sized apparatus 10 is chosen for implantation. For
example, the main body portion 48 of the expandable anchoring
member 42 can be appropriately-sized so that the diameter of the
main body portion corresponds to the diameter of the native mitral
annulus 36. Additionally, the first and second end portions 44 and
46 of the expandable anchoring member 42 can also be
appropriately-sized so that the first and second end portions
respectively contact the superior and inferior aspects 78 and 80 of
the mitral annulus 36 when the expandable anchoring member is in an
expanded configuration.
[0056] After selecting an appropriately-sized apparatus 10, the
puncture tool 76 is used to puncture the chest wall and extend
through the apical portion of the left ventricle 20 into the left
ventricular chamber. The delivery catheter 70 is then urged through
the puncture tool 76 as shown in FIG. 4 so that the delivery
catheter is positioned at a distal end portion 82 of the puncture
tool. Both the puncture tool 76 and the delivery catheter 70 are
then progressively withdrawn so that the first end portion 44 of
the expandable anchoring member 42 expands to contact the superior
aspect 78 of the native mitral annulus 36. Once the delivery
catheter 70 and the puncture tool 76 have been completely withdrawn
from the left ventricle 20, the main body portion 48 and the second
end portion 46 of the expandable anchoring member 42 expand into
the native mitral annulus 36 (FIG. 5). With the apparatus 10
securely positioned in the native mitral annulus 36, normal blood
flow can resume through the prosthetic valve 68.
[0057] Another embodiment of the present invention is illustrated
in FIGS. 6A-E. The apparatus 10.sub.a is identically constructed as
the apparatus 10 shown in FIGS. 1A-E, except where as described
below. In FIGS. 6A-E, structures that are identical as structures
in FIGS. 1A-E use the same reference numbers, whereas structures
that are similar but not identical carry the suffix "a".
[0058] An apparatus 10.sub.a for replacing a native cardiac valve,
such as a native mitral valve 30 can comprise an expandable support
member 56 and a prosthetic cardiac 68 valve operably secured within
the expandable support member. As shown in FIGS. 6A-E, the
apparatus 10.sub.a can further include a securing member 84
operably connected to the expandable support member 56. The
securing member 84 can comprise an elongated body member 86 having
a first end 88, a second end 90, and a main body portion 92
extending between the first and second ends. The securing member 84
can be operably secured to the expandable support member 56 using
any one or combination of known fastening means (not shown), such
as sutures, clips, pins, staples, adhesives, or the like.
[0059] The second end 90 of the elongated body member 84 can
include a first attachment member 94 operably connected thereto for
contacting the inferior aspect of the native cardiac valve annulus
when the expandable support member 56 is in an expanded
configuration. As shown in FIGS. 6A-E, the first end 88 of the
elongated body member 86 can also include a second attachment
member 96 operably connected thereto for contacting the superior
aspect of the native cardiac valve annulus when the expandable
support member 56 is in an expanded configuration. The first and
second attachment members 94 and 96 can be made from any one or
combination of flexibly resilient, medical grade materials,
including, for example, Nitinol, stainless steel, or other suitable
metals or plastics having shape memory characteristics.
[0060] The first and second attachment members 94 and 96 can have a
variety of configurations. As shown in FIGS. 6A-C, for example, the
first and second attachment members 94 and 96 can include flexible,
rod-shaped members 98. The rod-shaped members 98 can be joined to
or integrally formed with the elongated body member 86 so that the
rod-shaped members can transition from a collapsed configuration
(indicated by the dashed lines) to an expanded configuration. In
the collapsed configuration, the rod-shaped members 98 can extend
substantially parallel to the elongated body member 86. In the
expanded configuration, the rod-shaped members 98 can extend
substantially axial to the elongated body member 86. As described
in more detail below, the rod-shaped members 98 located at the
first and second ends 88 and 90 of the elongated body member 86 can
respectively contact the superior and inferior aspects 78 and 80 of
the mitral annulus 36 when the apparatus 10.sub.a is in an expanded
configuration.
[0061] As shown in FIGS. 6B-D, the first and second attachment
members 94 and 96 can also comprise a windable coil 100. The
windable coil 100 can be made of a flexible wire or rod capable of
transitioning between an expanded configuration and a collapsed
configuration. In the expanded configuration (indicated by the
dashed lines), the windable coil 100 can obtain a substantially
linear configuration so that the windable coil extends
substantially parallel to the elongated body member 86. In the
collapsed configuration (FIGS. 6B-D), the windable coil 100 can
obtain a substantially circular configuration and extend
substantially axial to the elongated body member 86. As described
in more detail below, each of the windable coils 100 located at the
first and second ends 88 and 90 of the elongated body member 86 can
respectively contact the superior and inferior aspects 78 and 80 of
a native mitral annulus 36 when the apparatus 10.sub.a is in an
expanded configuration.
[0062] The first and second attachment members 94 and 96 can
additionally comprise an anchoring ring 102 (FIG. 6E). The
anchoring ring 102 can be similarly or identically constructed as
the first and second end portions 44 and 46 of the expandable
anchoring member 42 shown in FIGS. 3A-B. In an expanded
configuration, the anchoring ring 102 can have a bulbous shape and
extend substantially axial to the elongated body member 86. In a
collapsed configuration (indicated by dashed lines), the anchoring
ring 102 can extend substantially parallel to the elongated body
member 86. The anchoring ring 102 can be made of a flexible,
mesh-like material having shape memory characteristics.
[0063] It will be appreciated that the apparatus 10.sub.a shown in
FIGS. 6A-E can additionally include a layer 104 (FIG. 8) of
material that extends around all or a portion of the expandable
support member 56. The layer 104 of material can be made of any one
or combination of known biocompatible materials, some of which are
described above. For example, the layer 104 can be made of PTFE or
ePTFE. The layer 104 of material can function as a seal to prevent
leakage of blood between the left atrium 16 and the left ventricle
20, for example, when the apparatus 10.sub.a is implanted in a
heart 12.
[0064] The apparatus 10.sub.a shown in FIGS. 6A-E can be used to
replace a native mitral valve 30, for example, using any one or
combination of known surgical methods. As shown in FIG. 7, for
example, an apical puncture method can be used to deliver the
apparatus 10.sub.a shown in FIG. 6A to a native mitral valve 30. It
will be appreciated, however, that other percutaneous,
transvascular, and/or open surgical methods may be used to deliver
the apparatus 10.sub.a to a native mitral valve 30. It will also be
appreciated that the method of the present invention will typically
entail gaining access to a beating heart 12; however, the present
invention may also be used for intravascular stopped-heart access
as well as stopped-heart open chest procedures.
[0065] The apparatus 10.sub.a shown in FIG. 6A can be delivered to
a native mitral valve 30 using an apical puncture method similar or
identical to the apical puncture method described above. Briefly,
one step of the method can include placing the apparatus 10.sub.a
into a delivery catheter 70. Prior to placing the apparatus
10.sub.a into the delivery catheter 70, the dimensions of the
native mitral valve 30 and the native mitral annulus 36 can be
determined. After selecting an apparatus 10.sub.a whose dimensions
correspond to the dimensions of the native mitral valve 30 and the
native mitral annulus 36, a puncture tool 76 can be used to
puncture the chest wall. The puncture tool 76 can then be extended
through the apical portion of the left ventricle 20 into the left
ventricular chamber. Next, the delivery catheter 70 can be urged
through the puncture tool 76 as shown in FIG. 7 so that the
delivery catheter is positioned at a distal end portion 82 of the
puncture tool.
[0066] Both the puncture tool 76 and the delivery catheter 70 can
then be progressively withdrawn from the left ventricle 20 so that
the expandable support member 56 can expand into contact with the
native mitral annulus 36, and the rod-shaped members 98 can
transition from the collapsed configuration to the expanded
configuration. As the delivery catheter 70 and the puncture tool 76
are completely removed from the left ventricle 20, the rod-shaped
members 98 located at the first and second ends 88 and 90 of the
elongated body members 86 can respectively contact the superior and
inferior aspects 78 and 80 of the mitral annulus 36 and thereby
secure the apparatus 10.sub.a in the native mitral annulus (FIG.
8). With the apparatus 10.sub.a securely positioned in the native
mitral annulus 36, normal blood flow can resume through the
prosthetic valve 68. Another embodiment of the present invention is
illustrated in FIG. 9.
[0067] The apparatus 10.sub.b is identically constructed as the
apparatus 10.sub.a shown in FIGS. 6A-E, except where as described
below. In FIG. 9, structures that are identical as structures in
FIGS. 6A-E use the same reference numbers, whereas structures that
are similar but not identical carry the suffix "b".
[0068] An apparatus 10.sub.b for replacing a native cardiac valve,
such as a mitral valve 30 can comprise an expandable support member
56 and a prosthetic valve 68 operably secured within the expandable
support member. As shown in FIG. 9, the apparatus 10.sub.b can
further include a securing member 84 operably connected to the
expandable support member 56. The securing member 84 can comprise
an elongated body member 86 having a first end 88, a second end 90,
and a main body portion 92 extending between the first and second
ends. The securing member 84 can be operably secured to the
expandable support member 56 using any one or combination of known
fastening means (not shown), such as sutures, clips, pins, staples,
adhesives, or the like.
[0069] The second end 90 of the elongated body member 86 can also
include a first attachment member 94 operably connected thereto for
embedding into the annular tissue at the inferior aspect of a
native cardiac valve annulus. As shown in FIG. 9, the first
attachment member 94 can include at least one rod-shaped puncturing
member 106. The puncturing member 106 can have a fixed length or,
alternatively, the puncturing member can have a compressible,
spring-like configuration (not shown). The puncturing member 106
can have a needle- or barb-like shape to facilitate penetration of
the puncturing member into annular tissue.
[0070] The apparatus 10.sub.b is capable of transitioning between a
collapsed configuration and an expanded configuration. As shown in
FIG. 9, the puncturing member 106 can extend substantially axial to
the elongated body member 86 in the expanded configuration. In the
collapsed configuration (indicated by the dashed lines), the
puncturing member 106 can extend substantially parallel to the
elongated body member 86. As described in more detail below, the
puncturing member 106 can be used to secure the apparatus 10.sub.b
in a native cardiac valve annulus.
[0071] The apparatus 10.sub.b shown in FIG. 9 can be delivered to a
native cardiac valve, such as a mitral valve 30 using an apical
puncture method similar or identical to the apical puncture method
described above. Briefly, one step of the method can include
placing the apparatus 10.sub.b into a delivery catheter 70. Prior
to placing the apparatus 10.sub.b into the delivery catheter 70,
the dimensions of the native mitral valve 30 and the native mitral
annulus 36 can be determined. After selecting an apparatus 10.sub.b
whose dimensions correspond to the dimensions of the native mitral
valve 30 and the native mitral annulus 36, the puncture tool 76 can
be used to puncture the chest wall. The puncture tool 76 can then
be extended through the apical portion of the left ventricle 20
into the left ventricular chamber. Next, the delivery catheter 70
can be urged through the puncture tool 76 so that the delivery
catheter is positioned at a distal end portion 82 of the puncture
tool (not shown).
[0072] Both the puncture tool 76 and the delivery catheter 70 can
then be progressively withdrawn from the left ventricle 20 so that
the expandable support member 56 expands into contact with the
native mitral annulus 36. As the delivery catheter 70 and the
puncture tool 76 are completely removed from the left ventricle 20,
each of the puncture members 106 can transition from the collapsed
configuration to the expanded configuration. In the expanded
configuration, each of the puncture members 106 can penetrate into
the annular tissue at the inferior aspect 80 of the native mitral
annulus 36 and thereby secure the apparatus 10.sub.b in the native
mitral annulus (FIG. 10). With the apparatus 10.sub.b securely
positioned in the native mitral annulus 36, normal blood flow can
resume through the prosthetic valve 68.
[0073] Another embodiment of the present invention is illustrated
in FIG. 11. The apparatus 10.sub.c is identically constructed as
the apparatus 10.sub.a shown in FIGS. 6A-E, except where as
described below. In FIG. 11, structures that are identical as
structures in FIGS. 6A-E use the same reference numbers, whereas
structures that are similar but not identical carry the suffix
"c".
[0074] An apparatus 10.sub.c for replacing a native cardiac valve,
such as a mitral valve 30 can comprise a prosthetic valve 68
operably secured to a securing member 84. The securing member 84
can comprise an elongated body member 86 having a first end 88, a
second end 90, and a main body portion 92 extending between the
first and second ends. The securing member 84 can be operably
secured to the prosthetic valve 68 using any one or combination of
known fastening means (not shown), such as sutures, clips, pins,
staples, adhesives, or the like.
[0075] The second end 90 of the elongated body member 86 can
include a first attachment member 94 operably connected thereto for
contacting the inferior aspect of a native cardiac valve annulus
when the apparatus 10.sub.c is in an expanded configuration. As
shown in FIG. 11, the first end 88 of the elongated body member 86
can also include a second attachment member 96 operably connected
thereto for contacting the superior aspect of a native cardiac
valve annulus when the apparatus 10.sub.c is in an expanded
configuration. The first and second attachment members 94 and 96
can be made from any one or combination of flexibly resilient,
medical grade materials, including, for example, Nitinol, stainless
steel, or other suitable metals or plastics having shape memory
characteristics.
[0076] The first and second attachment members 94 and 96 can have a
variety of configurations. As shown in FIG. 11, for example, the
first and second attachment members 94 and 96 can include flexible,
rod-shaped members 98. It will be appreciated, however, that the
first and second attachment members 94 and 96 can also comprise any
one or combination of the structures illustrated in FIGS. 6A-E. The
rod-shaped members 98 can be joined to or integrally formed with
the elongated body member 86 so that the rod-shaped members can
transition from a collapsed configuration (indicated by dashed
lines) to an expanded configuration. In the collapsed
configuration, the rod-shaped members 98 can extend substantially
parallel to the elongated body member 86. In the expanded
configuration, the rod-shaped members 98 can extend substantially
axial to the elongated body member 86. As described in more detail
below, the rod-shaped members 98 located at the first and second
ends 88 and 90 of the elongated body member 86 can respectively
contact the superior and inferior aspects 78 and 80 of the mitral
annulus 36 when the apparatus 10.sub.c is in an expanded
configuration.
[0077] The apparatus 10.sub.c shown in FIG. 11 can be used to
replace a native cardiac valve, such as a native mitral valve 30
using an apical puncture method similar or identical to the apical
puncture method described above. Briefly, one step of the method
can include placing the apparatus 10.sub.c into a delivery catheter
70. Prior to placing the apparatus 10.sub.c into the delivery
catheter 70, the dimensions of the native mitral valve 30 and the
native mitral annulus 36 can be determined. After selecting an
apparatus 10.sub.c whose dimensions correspond to the dimensions of
the native mitral valve 30 and the native mitral annulus 36, a
puncture tool 76 can be used to puncture the chest wall. The
puncture tool 76 can then be extended through the apical portion of
the left ventricle 20 into the left ventricular chamber. Next, the
delivery catheter 70 can be urged through the puncture tool 76 so
that the delivery catheter is positioned at a distal end portion 82
of the puncture tool (not shown).
[0078] Both the puncture tool 76 and the delivery catheter 70 can
then be progressively withdrawn from the left ventricle 20 so that
prosthetic valve 68 expands into contact with the native mitral
annulus 36, and the rod-shaped members 98 located at the first end
88 of each of the elongated body members 86 transitions from the
collapsed configuration to the expanded configuration. As the
delivery catheter 70 and the puncture tool 76 are completely
removed from the left ventricle 20, the rod-shaped members 98
located at the first and second ends 88 and 90 of each of the
elongated body members 86 can respectively contact the superior and
inferior aspects 78 and 80 of the mitral annulus 36, thereby
securing the apparatus 10.sub.c in the native mitral annulus (FIG.
12). With the apparatus 10.sub.c securely positioned in the native
mitral annulus 36, normal blood flow can resume through the
prosthetic valve 68.
[0079] From the above description of the invention, those skilled
in the art will perceive improvements, changes and modifications.
For example, it will be appreciated that the methods of the present
invention can include implanting an expandable anchoring member 42
or an expandable support member 56, without a prosthetic valve 68
attached therein, in a native cardiac valve annulus. After the
expandable anchoring member 42 or the expandable support member 56
is securely positioned in the native cardiac valve annulus, a
prosthetic valve 68 can then be secured therein using any one or
combination of known fastening means. Such improvements, changes
and modifications are within the skill of the art and are intended
to be covered by the appended claims.
* * * * *