U.S. patent application number 11/756530 was filed with the patent office on 2007-12-06 for prosthetic insert for improving heart valve function.
Invention is credited to David Alon, David L. Hauser, Jan Otto Solem.
Application Number | 20070282429 11/756530 |
Document ID | / |
Family ID | 38779486 |
Filed Date | 2007-12-06 |
United States Patent
Application |
20070282429 |
Kind Code |
A1 |
Hauser; David L. ; et
al. |
December 6, 2007 |
PROSTHETIC INSERT FOR IMPROVING HEART VALVE FUNCTION
Abstract
A device and methods for improving the function of a heart
valve, such as an aortic valve, is disclosed. In one embodiment,
the device includes an insert member configured for insertion
between leaflets of an aortic valve. The insert member preferably
includes three radial arms extending outwardly from a central
portion. The device also includes an anchoring member which is
coupled to the insert member and configured for maintaining the
insert member within the heart valve. In operation, each of the
arms fills gaps between heart valve leaflets, thereby minimizing or
preventing regurgitation through the heart valve.
Inventors: |
Hauser; David L.; (Newport
Beach, CA) ; Solem; Jan Otto; (Stetten, CH) ;
Alon; David; (Gan-Ner, IL) |
Correspondence
Address: |
EDWARDS LIFESCIENCES CORPORATION
LEGAL DEPARTMENT, ONE EDWARDS WAY
IRVINE
CA
92614
US
|
Family ID: |
38779486 |
Appl. No.: |
11/756530 |
Filed: |
May 31, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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60810085 |
Jun 1, 2006 |
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Current U.S.
Class: |
623/1.16 ;
623/1.36; 623/2.18; 623/900 |
Current CPC
Class: |
A61F 2220/0016 20130101;
A61F 2/2412 20130101; A61F 2210/0014 20130101; A61F 2/2436
20130101; A61F 2220/0008 20130101; A61F 2/2466 20130101; A61F 2/246
20130101; A61F 2/2418 20130101; A61F 2/2445 20130101 |
Class at
Publication: |
623/1.16 ;
623/900; 623/2.18; 623/1.36 |
International
Class: |
A61F 2/24 20060101
A61F002/24; A61F 2/94 20060101 A61F002/94 |
Claims
1. A device for improving the function of a heart valve,
comprising: an insert member comprising a body configured for
insertion between leaflets of the heart valve, the body having at
least first and second solid leaflet-contacting surfaces; and an
anchoring member coupled to the insert member, the anchoring member
comprising a stent having an open-frame structure configured to be
radially compressible to a compressed state for delivery to a
deployment site adjacent the heart valve and radially expandable to
an expanded state at the deployment site, wherein each of the
leaflet-contacting surfaces is configured to contact a leaflet of
the heart valve when the heart valve closes to minimize
regurgitation through the heart valve.
2. The device of claim 1, wherein the anchoring member is sized to
engage an inner wall of an aorta when in the expanded state.
3. The device of claim 1, further comprising at least one spacer
for coupling the insert member to the anchoring member, the at
least one spacer being of sufficient length to permit the anchoring
member to be deployed within an aorta with the insert member
inserted in the an aortic valve such that the anchoring member and
insert member are on opposite sides of the coronary ostia.
4. The device of claim 3, wherein the length of the at least one
spacer is at least 6 mm.
5. The device of claim 1, wherein the at least first and second
solid leaflet-contacting surfaces comprise three solid
leaflet-contacting surfaces, each being configured to contact a
leaflet of an aortic heart valve when the aortic heart valve closes
to minimize regurgitation through the aortic heart valve.
6. The device of claim 5, wherein the body comprises three
angularly-spaced extension portions that extend radially outward
from a central portion of the insert member, the extension portions
defining the leaflet-contacting surfaces.
7. The device of claim 6, wherein each of the extension portions
are tapered in width.
8. The device of claim 1, wherein the body is configured to be
radially compressible to a compressed state for delivery to the
deployment site adjacent the heart valve and radially expandable to
an expanded state at the deployment site.
9. The device of claim 1, wherein the stent is self-expanding.
10. The device of claim 1, wherein the stent is
balloon-expandable.
11. The device of claim 1, wherein the stent supports a prosthetic
valve for occluding blood flow in one direction through the
stent.
12. The device of claim 1, wherein the anchoring member is formed
from a shape memory alloy.
13. The device of claim 1, wherein the body comprises an inner
support and an outer layer defining the leaflet-contacting
surfaces, the outer layer comprising a biological material to
inhibit abrasion of the heart valve leaflets when the heart valve
leaflets contact the leaflet-contact surfaces on the body of the
insert member.
14. The device of claim 13, wherein the biological material
comprises animal pericardial tissue.
15. The device of claim 13, wherein the inner support comprises a
shape memory material.
16. The device of claim 1, wherein the body of the insert member
extends partially into the stent.
17. A device for improving the function of an aortic valve,
comprising: an insert member comprising a body configured for
insertion between leaflets of the aortic valve, the body having a
central portion and three angularly-spaced arms extending radially
outward from the central portion; and an anchoring member
configured for securement to a muscular wall inside a heart
chamber, the anchoring member comprising at least one engagement
member configured to engage the muscular wall, wherein the
anchoring member comprises an elongated shaft having a first end
connected to the insert member and a second end connected to the at
least one engagement member.
18. The device of claim 17, wherein the heart chamber is a left
ventricle.
19. The device of claim 17, wherein the body has at least one
tapered end region.
20. The device of claim 17, wherein the at least one engagement
member comprises a plurality of expandable fingers configured to
penetrate and engage the muscular wall of the heart.
21. The device of claim 17, wherein the at least one engagement
member comprises a first plate and a second plate, the first and
second plates being located on opposites sides of the muscular wall
of the heart, wherein the first plate is disposed on the elongated
shaft inside the chamber of the heart and the second plate is
disposed on the elongated shaft outside of the chamber of the
heart.
22. A device for improving the function of an aortic valve,
comprising: an insert member comprising a body having three
angularly-spaced arms extending radially outwardly for insertion
between leaflets of the aortic valve, the three angularly-spaced
arms being shaped to prevent regurgitation through the aortic
valve; and an expandable anchoring member coupled to the insert
member, the anchoring member configured for deployment within an
aorta.
23. The device of claim 22, further comprising at least one spacer
extending between the insert member and the anchor member.
24. The device of claim 23, wherein the at least one spacer has
sufficient length to permit the anchoring member to be deployed in
an aorta while the insert member is deployed in the aortic valve
such that the anchoring member and the insert member are on
opposite sides of the coronary ostia.
25. The device of claim 23, wherein the at least one spacer is an
elongated rod.
26. The device of claim 22, wherein the anchoring member is an
expandable stent having an open-frame construction.
27. The device of claim 23, wherein the spacer comprises a
plurality of elongated rods extending between and connected to the
anchoring member and the insert member.
28. A method for improving the function of an aortic valve,
comprising: providing a prosthetic device having an anchoring
member and an insert member, the insert member being configured to
reduce regurgitation through the aortic valve; deploying the
anchoring member in an aorta; and deploying the insert member in
the aortic valve, wherein the anchoring member maintains the insert
member within the aortic valve.
29. The method of claim 28, wherein the anchoring member and the
insert member are delivered percutaneously through the subject's
vasculature in a compressed state.
30. The method of claim 29, wherein the insert member of the
prosthetic device is retained in a delivery sheath while delivered
through the subject's vasculature.
31. The method of claim 29, wherein the anchoring member comprises
an expandable stent that is mounted in a compressed state on a
balloon of a delivery catheter.
32. The method of claim 28, wherein deploying the anchoring member
of the prosthetic device comprises deploying the anchoring member
above the ostia of the coronary arteries.
33. The method of claim 28, wherein the insert member has three
arms extending radially outward from a central portion and
deploying the insert member in the aortic valve comprises
positioning the insert member such that the arms are located within
gaps between leaflets of the aortic valve.
34. The method of claim 29, wherein the anchoring member and the
insert member are mounted on a common delivery catheter for
simultaneous delivery through the subject's vasculature.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional
Patent Application No. 60/810,085, filed Jun. 1, 2006, which is
incorporated herein by reference in its entirety.
FIELD OF THE DISCLOSURE
[0002] The disclosure relates to the field of implantable cardiac
prosthetics and in particular, to a cardiac prosthetic insert for
reducing regurgitation through a heart valve, such as the aortic
valve, and to methods of implanting the cardiac prosthetic
insert.
BACKGROUND
[0003] Heart valve regurgitation, or leakage from the outflow to
the inflow side of a heart valve, is a condition that occurs when a
heart valve fails to close properly. Heart valve regurgitation
decreases the efficiency of the heart, reduces blood circulation
and adds stress to the heart. In early stages, heart valve
regurgitation leaves a person fatigued and short of breath. If left
unchecked, the problem can lead to congestive heart failure,
arrythmias or death.
[0004] Regurgitation through the aortic valve, sometimes referred
to as aortic insufficiency, is a serious problem that affects the
health of millions of adults. The aortic valve is positioned on the
left side of the heart between the left ventricle and the aorta. A
healthy aortic valve opens to allow blood to flow from the left
ventricle into the aorta during ventricular systole and then closes
to prevent blood from flowing backward from the aorta into the left
ventricle during ventricular diastole. However, over time, changes
in the geometric configurations of the aortic annulus, or other
causes such as calcification, infection and injury, may affect the
functionality of the aortic valve. As a result, the aortic valve
may not close completely during ventricular diastole, thereby
leading to regurgitation.
[0005] Aortic insufficiency is typically treated by replacing the
defective native valve with a prosthetic valve during open heart
surgery. However, open-heart surgery is highly invasive and is
therefore not an option for many high risk patients. Accordingly,
in recent years, less invasive methods, such as percutaneous valve
replacement, have been developed for replacing aortic valves. In an
example, a prosthesis including a stent and a valve is crimped into
a small profile and then delivered into the heart via a
percutaneous route. Once located at the treatment site, the
prosthesis is expanded to replace the function of the native aortic
valve. Although percutaneous valve replacement has shown great
promise, there are still challenges with respect to delivery
techniques, perivalvular leakage and durability of the valve.
Furthermore, when possible, it may be desirable to repair, rather
than replace, the native valve.
SUMMARY
[0006] Accordingly, disclosed herein is a device and method of use
for treating heart valve disease, involving in exemplary
embodiments, a minimally invasive procedure that does not require
extracorporeal circulation. Certain embodiments of such a device
and method desirably are capable of reducing or eliminating
regurgitation through a heart valve. It is also desirable that
embodiments of such a device and method be well-suited for delivery
in a percutaneous or minimally-invasive procedure. It is also
desirable that embodiments of such a device and method be
well-suited for repairing an aortic valve. It is also desirable
that such a device be safe, reliable and easy to deliver. It is
also desirable that embodiments of such a device and method be
applicable for improving heart valve function for a wide variety of
heart valve defects. It is also desirable that embodiments of such
a device and method be capable of improving valve function without
replacing the native valve.
[0007] Various embodiments of the present disclosure provide
improved devices and methods for improving the function of a
defective heart valve. Particular embodiments can be configured to
be implanted in a heart using a percutaneous or minimally invasive
procedure wherein extracorporeal circulation is not required.
[0008] In one representative embodiment of the present disclosure,
a prosthetic device includes an anchoring member and an insert
member configured for deployment between the leaflets of a native
valve, such as the aortic valve. The insert member is desirably
shaped to fill the gap(s) between the leaflets for creating a tight
seal during ventricular diastole and thereby minimizing or
preventing regurgitation through the aortic valve. The insert
member is desirably sized such that the native leaflets engage the
surfaces of the insert member. When configured for use with a
typical aortic valve, the insert member desirably includes three
arms extending radially outward from a central region. Each of the
arms is shaped for placement between adjacent leaflets of the
aortic valve. The anchoring member is provided for securing the
insert member in its deployed position. In exemplary embodiments,
the anchoring member takes the form of a stent configured for
deployment in the ascending aorta. In one variation, the insert
member can be configured (e.g. with two arms) for use with an
aortic valve having only two leaflets. In another variation, the
insert member can be configured for use in a pulmonary valve for
treating pulmonary insufficiency.
[0009] In another representative embodiment of the present
disclosure, a prosthetic device includes an anchoring member formed
of a stent and an insert member configured for deployment between
the leaflets of a native aortic valve. The anchoring member
desirably includes a valve member for providing unidirectional
flow. The anchoring member is desirably configured for delivery
into an ascending aorta. The stent is expanded, either by
self-expansion or by balloon expansion, such that the stent is
anchored in the aorta. After deployment, the valve member in the
stent prevents or minimizes blood from flowing backward through the
aorta. The insert member is delivered into the native aortic valve
to improve the native valve function. Accordingly, two separate
valves (e.g., stented valve and native valve) work in tandem for
preventing regurgitation through the aortic annulus. By deploying
the insert member in the native valve, the native valve is allowed
to function as it should and blood enters the coronary arteries in
a substantially natural manner. The stented valve supplements the
function of the native valve. If desired, the stented valve could
be constructed to close before or after (desirably after) the
native valve to further influence and improve the native valve
function and also to improve hemodynamics.
[0010] In a representative embodiment, a system and method are
provided for treating a defective heart valve. The system includes
a prosthetic device including an anchoring member and an insert
member. The system further includes a delivery catheter for
delivering the prosthetic device into the heart via a percutaneous
approach. The delivery catheter desirably includes an elongate
sheath having a lumen sized to receive the prosthetic device. In
exemplary embodiments, the prosthetic device is held within the
sheath in a collapsed configuration during advancement through the
subject's vasculature. In one variation, the sheath is configured
for retrograde advancement and may be configured with a deflectable
end portion for facilitating navigation around the aortic arch.
After reaching the treatment site, the sheath is moved proximally
relative to the prosthetic device to eject the device from the
sheath. The device is then allowed to expand such that the insert
conforms to the gaps in the aortic valve and the anchoring member
engages the inner wall of the aorta.
[0011] In another representative embodiment of the present
disclosure, a prosthetic device includes an anchoring member and an
insert member having three expandable arms configured for
deployment between the gaps in an insufficient aortic valve. Each
arm desirably includes an expandable region that opens in a manner
somewhat similar to a parachute for preventing regurgitation.
During ventricular systole, each expandable region collapses such
that the flow of blood through the aortic valve is not impeded.
[0012] In a certain representative embodiment of the present
disclosure, a prosthetic device includes an insert member
configured for deployment within an aortic valve and an anchoring
member configured for securement within the left ventricle. An
elongate body portion is provided for coupling the insert member to
the anchoring member. If one variation, the prosthetic device can
be delivered in multiple stages. In a first stage, the anchoring
member is delivered and is then allowed to grow into the heart
wall. After sufficient in-growth has occurred, in a second stage,
the insert member is attached to the anchoring member.
[0013] In another representative embodiment of the present
disclosure, a prosthetic device includes an anchoring member and an
insert member configured for deployment between anterior and
posterior leaflets of a mitral valve. The insert member is
desirably shaped to fill the gap between native leaflets for
preventing regurgitation through the mitral valve. The insert
member is sized such that the mitral valve leaflets engage the
surfaces of the insert member to create a tight seal during
ventricular systole. In a variation of this embodiment, one or more
passageways are provided through the insert member for allowing
blood to flow through the device in one direction to further
improve valve function.
[0014] The foregoing and other features will become more apparent
from the following detailed description of several embodiments,
which proceeds with reference to the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 illustrates a cross-sectional view of a heart.
[0016] FIG. 2 is a perspective view of a prosthetic device
including an anchoring member and an insert member configured for
deployment between leaflets of a native aortic valve.
[0017] FIG. 3 is a cross-sectional view of an insert member with an
outer coating of biocompatible material.
[0018] FIG. 4 is a cross-sectional view of the insert member of
FIG. 2 positioned in an aortic valve.
[0019] FIG. 5 is a partial cut-away view of the aorta illustrating
the prosthetic device of FIG. 2 deployed within a subject to treat
aortic insufficiency.
[0020] FIG. 6 is a perspective view illustrating an embodiment of a
prosthetic device wherein the insert member is directly attached to
the anchoring member.
[0021] FIG. 7 is a cross-sectional view of the insert member of
FIG. 6 contained within a sheath in a contracted condition for
delivery to a treatment site.
[0022] FIG. 8 illustrates the insert member of FIG. 6 after being
ejected from the sheath and expanding into an expanded
condition.
[0023] FIG. 9A is a perspective view of a prosthetic device
including an insert member for deployment in the aortic valve and
an anchoring member with engagement members for securement to the
left ventricle.
[0024] FIG. 9B is an exploded view of an exemplary embodiment of a
plurality of engagement members shown in an expanded state.
[0025] FIG. 9C is a perspective view of the plurality of engagement
members of FIG. 9B shown in a compressed state for delivery to the
heart.
[0026] FIG. 10 is a variation of the embodiment shown in FIG. 9A
wherein an alternative anchoring member is provided.
[0027] FIG. 11 is a perspective view of a prosthetic device similar
to the embodiment illustrated in FIG. 2 wherein the anchoring
member includes a stent and a valve member for deployment in the
ascending aorta.
[0028] FIG. 12 is a perspective view of a prosthetic device similar
to the embodiment illustrated in FIG. 2 in which the insert member
is formed with two arms.
[0029] FIG. 13 is a perspective view of a prosthetic device
including an anchoring member and an insert member deployed in a
heart for treating an insufficient mitral valve.
[0030] FIG. 14 is a cross-sectional view of the insert member of
FIG. 13.
[0031] FIG. 15 is a cross-sectional view illustrating an insert
member formed with a passageway and valve member for allowing blood
to flow through the insert member in one direction.
DETAILED DESCRIPTION OF SEVERAL EMBODIMENTS
[0032] I. Explanation of Terms
[0033] Unless otherwise noted, all technical and scientific terms
used herein have the same meaning as commonly understood by one of
ordinary skill in the art to which this disclosure belongs. In
order to facilitate review of the various embodiments of the
disclosure, the following explanation of terms is provided:
[0034] The singular terms "a", "an", and "the" include plural
referents unless context clearly indicates otherwise. The term "or"
refers to a single element of stated alternative elements or a
combination of two or more elements, unless context clearly
indicates otherwise.
[0035] The term "includes" means "comprises." For example, a device
that includes or comprises A and B contains A and B, but may
optionally contain C or other components other than A and B.
Moreover, a device that includes or comprises A or B may contain A
or B or A and B, and optionally one or more other components, such
as C.
[0036] The term "proximal" refers to a portion of an instrument
closer to an operator, while "distal" refers to a portion of the
instrument farther away from the operator.
[0037] The term "subject" refers to both human and other animal
subjects. In certain embodiments, the subject is a human or other
mammal, such as a primate, cat, dog, cow, horse, rodent, sheep,
goat, or pig. In a particular example, the subject is a human
patient.
[0038] Although methods and materials similar or equivalent to
those described herein can be used in the practice or testing of
the present disclosure, suitable methods and materials are
described below. In case of conflict, the present specification,
including terms, will control. In addition, the materials, methods,
and examples are illustrative only and not intended to be
limiting.
[0039] II. An Anatomical Overview of the Human Heart
[0040] With reference to FIG. 1, a cross-sectional view of a heart
1 is provided. Blood flows through the superior vena cava 2 and the
inferior vena cava 4 into the right atrium 6 of the heart 1. The
tricuspid valve 8 controls blood flow between the right atrium 6
and the right ventricle 15. The tricuspid valve 8 is closed when
blood is pumped out from the right ventricle 15 to the lungs.
Thereafter, the tricuspid valve 8 is opened to refill the right
ventricle 15 with blood from the right atrium 6. Free edges of
leaflets of the tricuspid valve 8 are connected via the chordae
tendinae 10 to the papillary muscles 12 in the right ventricle 15
for controlling the movements of the tricuspid valve 8. Blood from
the right ventricle 15 is pumped through the pulmonary valve 20 to
the pulmonary artery 22, which branches into arteries leading to
the lungs.
[0041] After exiting the lungs, the oxygenated blood flows through
the pulmonary veins 28 and enters the left atrium 26 of the heart
1. The mitral valve 30 controls blood flow between the left atrium
26 and the left ventricle 17. The mitral valve 30 is closed during
ventricular systole when blood is ejected from the left ventricle
17 into the aorta 34. Thereafter, the mitral valve 30 is opened to
refill the left ventricle 17 with blood from the left atrium 26.
Free edges of leaflets of the mitral valve 30 are connected via the
chordae tendinae 11 to the papillary muscles 13 in the left
ventricle for controlling the movements of the mitral valve 30.
Blood from the left ventricle 17 is pumped through the aortic valve
32 into the aorta 34 which branches into arteries leading to all
parts of the body. The aortic valve 32 includes three leaflets
(also known as flaps or cusps) collectively denoted by reference
numeral 36. Leaflets 36 open and close to control the flow of blood
into the aorta 34 from the left ventricle 17 of the heart as it
beats.
[0042] III. Prosthetic Device for Reducing Regurgitation through a
Heart Valve
[0043] She efficiency of the heart may be seriously impaired if any
of the heart valves is not functioning properly. For example, heart
valves may lose their ability to close properly due to dilation of
an annulus around the valve or a flaccid, prolapsed leaflet. The
leaflets may also have shrunk due to disease, such as rheumatic
disease, thereby leaving a gap in the valve between the leaflets.
The inability of the heart valve to close will cause blood to leak
backwards (opposite to the normal flow of blood), commonly referred
to as regurgitation, through the aortic valve into the left
ventricle. Regurgitation may seriously impair the function of the
heart since more blood will have to be pumped through the
regurgitating valve to maintain adequate circulation.
[0044] Embodiments of the present disclosure provide devices and
methods for improving the function of a defective heart valve, such
as an aortic valve. The devices and methods disclosed herein are
desirably delivered into a subject's heart using percutaneous or
minimally invasive surgical methods. Accordingly, desirable
delivery methods described herein do not require extracorporeal
circulation (e.g., blood from a subject's circulation being routed
outside the body to have a process applied to and then, returned of
the subject's circulation). For example, in one embodiment, a
delivery catheter (or similar delivery device) is inserted through
an incision in the chest wall and then through the cardiac tissue
(e.g., through the apex of the heart) into a chamber of the
patient's beating heart. The delivery catheter can allow a
prosthetic device to be delivered into the heart in a collapsed
configuration and then expanded within the heart for treating a
defective heart valve. Because the desired delivery methods do not
require extracorporeal circulation, complications are greatly
reduced as compared with traditional open-heart surgery.
[0045] FIG. 2 illustrates an example of a prosthetic device 100
which can be employed to reduce or eliminate regurgitation through
a heart valve, such as the aortic valve. The prosthetic device 100
includes an insert member 102 and an anchoring member 110. The
insert member 102 desirably includes a solid outer surface for
contacting native valve leaflets, such as the native aortic valve
leaflets. As used herein, a "solid" surface refers to a
non-perforated surface that does not include any openings through
which blood can pass. As illustrated in FIG. 2, the insert member
102 includes a first extension portion, or arm, 104, a second
extension portion, or arm, 106 and a third extension portion, or
arm, 108. The extension portions 104, 106, 108 desirably are
equally angularly-spaced about a central portion 112 of the insert
member 102 and extend radially outwardly therefrom. The prosthetic
device 100 can include a plurality of spacers or connecting members
120 for mounting the insert member 102 at a position spaced from
the anchoring member 110. As shown in FIG. 2, three such spacers or
connecting members 120 are provided in the illustrated embodiment
for coupling the insert member 102 to the anchoring member 110.
[0046] In the illustrated embodiment, the anchoring member 110
takes the form of a self-expanding or balloon-expandable stent
having an open-frame construction as depicted in FIG. 2. The
anchoring member can be made of various suitable expandable and/or
elastic materials, such as stainless steel, titanium, shape memory
alloys, or other biocompatible metals. In one example, the
anchoring member 110 is self-expanding and formed of shape memory
alloys, such as nickel titanium (NiTi) shape memory alloys, as
marketed, for example, under the trade name Nitinol. In another
example, the anchoring member 110 is balloon-expandable and formed
of stainless steel or other suitable materials.
[0047] In particular embodiments, the anchoring member 110
comprises a stent having a plurality of angularly-spaced axial
struts, or support members, that extend axially (longitudinally) of
the member. The anchoring member 110 can also include a plurality
of axially-spaced, circumferential bands, or struts, attached to
the axial struts. The circumferential struts are formed with
multiple bends that allow the anchoring member 110 to be compressed
to a smaller diameter for delivery to an implantation site and
expanded to its functional size for anchoring the insert member 102
to the heart. The circumferential struts can include a plurality of
linear strut members arranged in a zig-zag or saw-tooth
configuration defining bends between adjacent strut members. In
other examples, one or more of the circumferential bands can have a
curved or serpentine shape rather than a zig-zag shape. In
variations, the anchoring member 110 may further include fixation
or attachment members, such as barbs, staples, flanges, hooks, and
the like along the exterior of the anchoring member 110 for
enhancing the ability of the anchoring member 110 to anchor insert
member within the aorta. Further details of exemplary stents that
can be employed in the embodiments disclosed herein are disclosed
in U.S. Pat. No. 6,730,118, U.S. Pat. No. 6,767,362, and U.S. Pat.
No. 6,908,481, each of which is incorporated herein by reference in
its entirety.
[0048] Although the anchoring member is primarily described in the
form of a stent, it will be appreciated that a wide variety of
anchoring mechanisms may be used while remaining within the scope
of the present disclosure. For example, the anchoring member can be
formed by one or more retainers. In a particular example, the
anchoring member can be a plurality of spaced-apart retainers that
extend outwardly to contact tissue near or within the heart valve
annulus. The retainers are sized and configured to secure the body
to the heart valve annulus. For instance, the one or more retainers
can be circular bands formed of polyethylene, polypropylene,
polycarbonate, nylon, polytetrafluoroethylene, polyurethane,
stainless steel, Nitinol, titanium, polyimide, polyester,
shape-memory material, or a mixture thereof. The one or more
retainers can include protrusions, barbs, needles, hooks, and like
engagement members for assisting with anchoring the prosthetic
device within the heart valve.
[0049] The insert member 102 is configured for insertion between
the leaflets of an insufficient aortic valve so as to fill the gap
between the leaflets. In one specific example, the insert member
102 exhibits sufficient rigidity to substantially maintain its
deployed shape and is resilient and/or flexible enough to be
compressed to a reduced diameter for delivery in a delivery sheath.
The insert member can be formed from plastic, metal (e.g., shape
memory metal) or other biocompatible material suitable for
implantation into a subject. In particular examples, as illustrated
in FIG. 3, the insert member 102 can include an inner support layer
127 and an outer layer or sheath 128. The outer layer 128 can be
formed of a biocompatible material, such as a cloth-like or fabric
material (natural or synthetic) or a biological material, such as
collagen or biological tissue material in order to protect the
native leaflets from damage (e.g., to inhibit abrasion that could
occur in response to engagement and disengagement of the leaflets).
For instance, smooth animal pericardium such as equine, bovine
porcine or other animal pericardial tissue which is compatible with
the native leaflets may be included within the outer layer 128.
Such tissue may be tanned or fixed by a suitable tanning
environment or the pericardium can be cross-linked with
glutaraldehyde and heparin bonded by a detoxification process. In a
certain example, the biological tissue material can be one of the
NO-REACT.RTM. natural tissue products exhibit improved
biocompatibility and mitigate calcification and thrombus formation.
The outer layer 128 can cover the entire outer surface of the inner
layer 127 or selected portions of the outer surface, such as those
portions that come into contact with the native leaflets.
[0050] In certain examples, the diameter of the insert member 102
is similar to the diameter of the native aortic valve such that
each of the extension portions extends into a cusp between leaflets
in the aortic valve. As a result, the insert member 102 of the
device 100 remains centered within the aortic valve after
deployment. In certain examples, the diameter of the insert member
is about 18 mm to about 26 mm, with about 22 mm being a specific
example. The diameter of the insert member 102 can be slightly
smaller as compared to the diameter of the anchoring member 110.
This configuration allows the insert member to collapse or
fold-down to a reduced diameter for delivery in a delivery sheath.
Additionally, the length of the insert member can vary. For
example, in one embodiment, the length of the insert member is
approximately the same size as the length of the anchoring member.
In other examples, the length of the insert member is greater or
smaller than that of the anchoring member. In certain examples, the
length of the insert member is about 20 mm to about 30 mm, with
about 25 mm being a specific example.
[0051] As illustrated in FIG. 4, the cross-sectional profile of the
insert member 102 can be shaped such that the native leaflets 36a,
36b, 36c are capable of contacting the sides of the insert member
102 to create a tight seal during ventricular diastole. For
example, the three spaced apart extensions or arms 104, 106 and 108
extend radially outward from a central region 112 of the insert
member 102. In certain examples, the arms taper in width from the
central portion to the outer ends of the extension portions. For
example, each arm includes a first end 114 and a second end 116.
The first end 114 is of a greater width than the second end 116.
The arms each include a first side 122 and a second side 124, each
of which side is configured for contact with a native leaflet. The
ends 114, 116 and the sides 122, 124 can be configured with smooth
edges to minimize or eliminate hemolytic effects. Further, each of
the arms is configured to fill a gap between adjacent leaflets of
an aortic valve, thereby preventing regurgitation through the
aortic valve. The contact surfaces of the arms can exhibit
sufficient compliancy and/or flexibility to allow the native
leaflets to engage the insert member 102 and create a tight seal
without damaging the leaflets. For example, as described above,
each arm can include biocompatible material, such as collagen or
pericardial tissue to inhibit abrasion that could occur in response
to engagement or coaptation of the arms with the native
leaflets.
[0052] When used to treat an aortic valve, the cross-sectional
profile of the insert member can be minimized to limit resistance
to blood flow from the left ventricle into the aorta when the
aortic valve is fully open. Furthermore, one or both ends of the
insert member may be tapered or rounded such that there are no flat
surfaces facing perpendicular to the flow of blood. With respect to
the illustrated embodiment, it will be appreciated that the
prosthetic device is capable of minimizing or preventing
regurgitation without utilizing any moving parts. The device can
therefore achieve greater durability as compared with alternative
heart valve repair and replacement techniques that utilize moving
parts.
[0053] The insert member 102 can be configured with expandable
structures, such as moveable flaps, to further impede regurgitation
through the aortic valve. Each expandable structure can be
configured to fill a gap between adjacent native valve leaflets. In
one example, the movable flaps can be configured to open in a
manner similar to that of a parachute to block regurgitation of
blood between the leaflets of the native aortic valve. During
ventricular systole, the moveable flaps collapse to allow blood to
flow from the left ventricle, through the native aortic valve and
into the aorta in a substantially unimpeded manner. Additional
details regarding an expandable insert member (e.g., valve portion)
can be found in Applicant's co-pending U.S. application Ser. No.
11/407,582 (U.S. Patent Publication No. 2006/0241745), filed on
Apr. 19, 2006, which is hereby incorporated by reference in its
entirety. Principles and features of the expandable prosthetic
devices described in the '582 application, which are configured for
use with a mitral valve, are also applicable to the devices
described herein for use in the aortic valve.
[0054] As mentioned above and as illustrated in FIG. 2, the
prosthetic device 100 includes a plurality of spacers or connecting
members 120. Each connecting member can be generally cylindrical in
shape, although any other suitable shape may be employed. In
certain examples, the length of each connecting member is about 6
mm to about 14 mm, with about 10 mm being a specific example. Each
connecting member preferably couples an arm of the insert member
102 to the anchoring member 110. The connecting members 120 can
assist in stabilizing the insert member 102. Each connecting member
desirably exhibits sufficient rigidity to substantially maintain
the insert member in a fixed position relative to the anchoring
member. The connecting members can be formed of plastic, metal or
other biocompatible material suitable for implantation into a
subject. The connecting members 120 also minimize interference of
the prosthetic device with blood flow to the coronary arteries by
allowing the anchoring member 110 to be positioned above the
coronary ostia and the insert member 102 positioned in the native
aortic valve.
[0055] As best illustrated in FIG. 4, the native leaflets 36a, 36b,
36c of the aortic valve 32 contact the insert member 102 during
ventricular diastole to create a tight seal. By allowing the aortic
valve 32 to create a tight seal, regurgitation from the aorta into
the left ventricle is minimized or prevented. During ventricular
systole, the native leaflets open as they do naturally to allow
blood to be pumped from the left ventricle into the aorta. As can
be seen in FIG. 4, the cross-sectional area of the insert member
102 is relatively small as compared with the flow area through the
aortic annulus. Accordingly, in the illustrated embodiment, the
insert member 102 will not substantially impede the flow of blood
through the aortic valve during ventricular systole.
[0056] With reference to FIG. 5, the prosthetic device 100 is
illustrated after deployment within a subject. As illustrated in
FIG. 5, the anchoring member 110 is deployed in the aorta above the
aortic valve, such as above the ostia of the coronary arteries 38
such as to not interfere with the flow of blood through the
coronary arteries. The insert member 102 is deployed within the
native aortic valve to improve the function of the aortic valve.
For example, the insert member 102 is positioned within the native
aortic valve with each arm 104, 106 and 108 extending between
adjacent edges of two leaflets such that the leaflets of the aortic
valve 32 coapt with the arms 104, 106 and 108. The connecting
members 120 extend from the anchoring member 110 to the insert
member 102 for maintaining the insert member 102 in a substantially
fixed position. During ventricular diastole, the leaflets of the
aortic valve 32 close and press against the walls of the insert
member to create a tight seal. Although the native leaflets in an
insufficient or defective aortic valve may not be able to close
completely, the arms of the insert member 102 fill the gaps such
that little or no blood is allowed to pass from the aorta back into
the left ventricle.
[0057] As shown, the native aortic valve is not excised and
continues to function in a substantially normal manner. As a
result, over time, it may be possible to remove the prosthetic
device if the native valve is able to heal itself or if an
alternative treatment is found.
[0058] With reference to FIG. 6, a prosthetic device 200 according
to another embodiment is shown. Prosthetic device 200 includes an
insert member 102 and an anchoring member 110. The insert member
102 in the illustrated embodiment is directly coupled to the
anchoring member 110 rather than via the connecting members 120.
For example, the insert member can be coupled to the anchoring
member 110 via the proximal end 118 of the insert member 102, for
example with the proximal end of the insert member 102 received
partially within and surrounded by an end portion of the anchoring
member 110. The diameter of the insert member 102 in the
illustrated embodiment is less than the diameter of the anchoring
member 110. This configuration allows the insert member 102 to be
collapsed or folded during implantation, and then deployed within
the valve.
[0059] The disclosed prosthetic devices can be configured to be
delivered in a percutaneous or minimally invasive procedure in
which only a small access incision is required. In one example, the
prosthetic device can be configured so that it can be crimped or
otherwise collapsed into a smaller profile and then placed in a
delivery sheath for advancement to the treatment site. FIG. 7, for
example, illustrates a prosthetic device 200 in a collapsed
condition within a sheath 142. As shown, the insert member 102 can
be configured to be sufficiently flexible such that the arms can be
folded or caused to assume a curved profile to temporarily reduce
the profile of the insert during delivery. After being ejected from
the sheath 142, the anchoring member 110 and insert member 102
expand to a fully expanded condition as shown in FIG. 8. When
delivered to the aortic valve in a percutaneous procedure, it may
be desirable to utilize a deflectable sheath to facilitate
navigation through the patient's vasculature and around the aortic
arch. Details regarding various embodiments of a deflectable sheath
configured to deliver a therapy device to an aortic valve can be
found in Applicant's co-pending U.S. application Ser. No.
11/152,288, filed Jun. 13, 2005, entitled "Heart Valve Delivery
System," which is hereby incorporated by reference in its
entirety.
[0060] FIG. 9A illustrates a prosthetic device 300 that can be used
to reduce or eliminate heart valve regurgitation, such as aortic
valve regurgitation. In this embodiment, the prosthetic device
includes an insert member 102 configured for insertion into the
aortic valve and an anchoring member 302 configured for securement
to the muscular wall in the left ventricle. The anchoring member
302 can include a plurality of engagement members 304, such as
hooks or fingers, that penetrate tissue along the muscular wall for
securing the insert member 102 to the heart. The engagement members
304 can be formed of any biocompatible material, such as
biocompatible metals or plastics, which is capable of penetrating
the left ventricle muscular wall to secure the insert member 102 to
the heart without substantially impairing the wall. The anchoring
member 302 can include an elongate body portion, or shaft, 306
which couples the engagement members 304 to the insert member 102.
In one example, the elongate body portion 306 and the engagement
members 304 can be formed from a single piece of material. In
another example, the elongate body portion 306 and the engagement
members 304 can be separately formed and subsequently coupled to
one another by any suitable means, such as welding. The elongate
body portion 306 and the engagement members 304 can be formed of
the same or different materials depending on the material
properties (elasticity, rigidity, resilience and the like) desired
for each part of the device 300.
[0061] The prosthetic device 300 can be positioned within the heart
to minimize aortic valve regurgitation by positioning the plurality
of engagement members 304 in the left ventricle near the left
ventricular apex. In the illustrated embodiment, a plurality of
fingers or hooks penetrates tissue along the left ventricle
muscular wall near the left ventricular apex. The insert member 102
is positioned in the aortic valve annulus such that an upper
portion and lower portion extend above and below the native aortic
valve and the arms of the insert member 102 are aligned with
coaptions of the three cusps of aortic valve so each leaflet moves
up and down between the insert arms.
[0062] FIGS. 9B and 9C illustrate the lower end portion of an
anchor member 302 with a plurality of engagement members 304 in the
form of elongated prongs. The elongated prongs 304 are desirably
configured to self-expand from the compressed configuration of FIG.
9C to a "flowered" or expanded configuration of FIG. 9B when
advanced out of a delivery sheath. This flowering is desirably
achieved with a self curving area 304a that deflects the prongs 304
radially outward from the center of the body 502 and rearward
toward the second end of the body. The prongs 304 are desirably
pointed or barbed to facilitate penetration and engagement with the
muscular wall of the heart.
[0063] The anchor member 302 can be formed from a single tube of
shape memory material, such as, for example, Nitinol. During
manufacture, the shape memory material may be cut using a
mechanical or laser cutting tool. After cutting the tube, the
expanded or flowered shape can be imparted to the memory of the
shape memory material with techniques known in the art (e.g. heat
setting the shape). Methods for manufacturing the anchor member are
described in detail in Applicant's co-pending U.S. application Ser.
No. 11/750,272 (hereinafter "the '272 application"), which is
incorporated herein by reference. In one preferred embodiment, the
anchor member is formed to have an expanded configuration that
conforms to the contours of the particular surface area of the
heart where the anchor member is to be deployed, as described in
the '272 application.
[0064] The surface of the anchor member 302, including the prongs
304, is desirably configured to promote tissue growth onto and even
into its surface. In one example this growth is achieved by
providing the anchor member with a relatively rough and/or porous
surface. Additionally, biological coatings of the types known in
the art can be included on the surface of the anchor member 302 to
promote healing and tissue growth.
[0065] FIG. 10 illustrates another variation of an anchoring member
402 wherein one or more anchors, such as the illustrated plates
404, are located on opposite sides of the muscular wall of the
heart for anchoring the prosthetic device 400 to the heart. The
plates 404 can be formed of any biocompatible material, such as
biocompatible metals or plastics. The anchoring member 402 includes
a shaft 406 having an upper end portion connected to the insert
member 102 and a lower-end portion that extends through the wall of
the heart. One plate 404 is disposed on the shaft inside the left
ventricle and another plate 404 is disposed on the shaft outside
the left ventricle to secure the shaft in place.
[0066] If desired, the prosthetic device may be deployed in
multiple stages wherein, in a first stage, the anchoring member is
attached to the aorta (or ventricular wall) before the insert
member is delivered. In a second stage, the insert member of the
device is connected to the anchoring member at a later time (e.g.,
hours, days or weeks later). The time between the first and second
stages advantageously allows tissue to heal and even grow over the
anchoring member, thereby further embedding the anchoring member in
the heart. Without the added stress that the insert member of the
device may impart on the tissue, the healing and over-growth may
proceed more rapidly with less adverse affects (e.g., unwanted
scarring). Additional details regarding exemplary anchoring
members, expandable insert members and two-stage deployment can be
found in the '272 application.
[0067] FIG. 11 shows another alternative embodiment of a prosthetic
device, indicated at 500. The anchoring member 110 can be a stent
and can include a valve member 130 mounted inside the stent. In the
illustrated embodiment, the valve member 130 is a three-leaflet
bioprosthetic valve. In particular examples, the anchoring member
and valve member may take the form of the Cribier-Edwards valve
manufactured by Edwards Lifesciences of Irvine, Calif. Additional
details regarding exemplary embodiments of a stented valve can be
found in U.S. Pat. No. 6,893,460, which is hereby incorporated by
reference in its entirety.
[0068] The valve member 130 in the stent ensures unidirectional
flow through the stent. The stent is desirably configured for
delivery into an ascending aorta. The stent is expanded, either by
self-expansion or by balloon expansion, such that the stent is
anchored in the aorta. After deployment, the valve member in the
stent prevents blood from flowing backward through the aorta. The
insert member is delivered into the native aortic valve to improve
the native valve function. Accordingly, two separate valves (i.e.,
the stented valve and the native valve) work in tandem for
inhibiting regurgitation through the aortic annulus. By deploying
the insert member in the native valve, the native valve is allowed
to function as it should and blood is allowed to flow into the
coronary arteries in a substantially natural manner. The stented
valve supplements the function of the native valve. If desired, the
stented valve could be constructed to close before or after the
native valve to further influence and improve the native valve
function and also to improve hemodynamics and/or perfusion into the
coronary arteries.
[0069] With reference to FIG. 12, a prosthetic device 600 according
to yet another embodiment is provided. The prosthetic device 600 is
configured for use in an abnormal aortic valve having only two
leaflets. To treat this portion of the population, an insert member
602 is provided with two arms 604, 606 for filling the gaps between
the leaflets. In addition, in certain aortic valves having three
leaflets, it may not be necessary to fill gaps between each of the
three leaflets. Accordingly, it may be desirable to use an insert
member of the type shown in FIG. 12 for preventing or reducing
regurgitation in a three leaflet valve.
[0070] For purposes of illustration, desirable embodiments of a
prosthetic device have been described above for use in a valve
normally having three leaflets, such as an aortic valve. However,
it will be recognized by those of ordinary skill in the art that
variations of the devices may also be used to treat another valve
with three leaflets, such as a pulmonary valve, in an analogous
manner. When used to treat the pulmonary valve, the anchoring
member (e.g., stent) can be configured for deployment in the
pulmonary trunk or a pulmonary artery. Alternatively, the anchoring
member may be secured within the right ventricle.
[0071] With reference now to FIGS. 13 through 15, a prosthetic
device 700 is configured for treating a bicuspid valve, such as a
defective mitral valve. As illustrated in FIG. 13, the prosthetic
device 700 includes an insert member 702 and an anchoring member
704. The insert member 702 comprises a body sized and shaped to
fill the gap between the anterior and posterior leaflets of an
insufficient mitral valve.
[0072] In one specific example, the insert member 102 exhibits
sufficient rigidity to substantially maintain its deployed shape
and is resilient and/or flexible enough to be compressed to a
reduced diameter for delivery in a delivery sheath. The insert
member can be formed from plastic, metal or other biocompatible
material suitable for implantation into a subject. In particular
examples, as described previously, the insert member can include an
outer layer or sheath substantially formed of a biocompatible
material, such as a cloth-like or fabric material (natural or
synthetic) or a biological material, such as collagen or biological
tissue material in order to protect the native leaflets from damage
(e.g., to inhibit abrasion that could occur in response to
engagement and disengagement of the leaflets). For instance, smooth
animal pericardium such as equine, bovine, porcine or other animal
pericardial tissue which is compatible with the native leaflets may
be included within the outer layer. Such tissue may be tanned or
fixed by a suitable tanning environment or the pericardium can be
cross-linked with glutaraldehyde and heparin bonded by a
detoxification process. In a certain example, the biological tissue
material can be one of the NO-REACT.RTM. natural tissue products
exhibit improved biocompatibility and mitigate calcification and
thrombus formation. The outer layer can cover the entire outer
surface of the insert member 102 or selected portions of the outer
surface, such as those portions that come into contact with the
native leaflets. The insert member 702 can be shaped with tapered
and/or smooth edges to minimize or eliminate hemolytic effects.
[0073] The cross-sectional profile of the insert member 702 is
shaped such that the native leaflets are capable of contacting the
sides 703a and 703b of the insert member 702 to create a tight
seal. As illustrated in FIGS. 13-15, the insert member 702
preferably has a crescent-shape cross-sectional profile to better
conform to the curvature of the native leaflets. The surface of the
insert member 702 can be of a compliancy that allows the native
leaflets to engage the insert member 702 to create a tight seal
without damaging the leaflets. For example, as described above, the
surface can comprise a biocompatible material, such as collagen or
pericardial tissue to inhibit abrasion that could occur in response
to engagement or coaptation of the insert member surface with the
native leaflets. In operation, the native leaflets of the mitral
valve press against the walls of the insert member during
ventricular systole to create a tight seal and prevent
regurgitation of blood from the left ventricle into the left
atrium.
[0074] In the illustrated embodiment, the anchoring member 704 of
the prosthetic device 700 includes a shaft or elongated body
portion 706, the lower end portion of which forms a penetration
member 708. Plates 709 can be disposed on the penetration member
708 on opposite sides of the heart wall to secure the shaft in
place. The body portion 706 and penetration member 708 of the
anchoring member 704 may be of any suitable shape and material that
imparts the material properties (elasticity, rigidity, resilience
and the like) desired for each part of the device 700. For example,
the penetration member 708 can be formed of any biocompatible
material, such as biocompatible metals or plastics, which is
capable of penetrating the left ventricle muscular wall to secure
the insert member 702 to the heart without substantially impairing
the wall.
[0075] In one example, the anchoring member 704 may be configured
for deployment in the left ventricle. FIG. 14 is a cross-sectional
view of the insert member 702 shown in FIG. 13. In this embodiment,
the insert member 702 can have a substantially solid cross-section.
In a variation, as shown in FIG. 15, the insert member 702 may
include a passageway extending along a longitudinal axis. The
passageway can be adapted to allow blood to flow through the insert
member in one direction. A valve member can be included within the
insert to ensure that blood flows in only one direction. In a
particular example, the valve member can comprise one or more flap
members 712 defining a slit or opening 710. The valve member mimics
the function of the target valve by allowing blood flow in only one
direction. Thus, blood flow passing into the passage from one
direction opens the flaps and thereby passes through the insert
member while blood moving into the passage from the opposite
direction is stopped by the valve.
[0076] IV. System and Methods for Reducing Regurgitation through a
Heart Valve
[0077] Disclosed herein are a system and methods for treating a
defective heart valve. In one embodiment, the system includes a
prosthetic device including an anchoring member, such as a
self-expandable anchoring member, and an insert member. The system
can further include a delivery catheter for delivering the
prosthetic device into the heart via a percutaneous approach. For
example, the catheter can be introduced percutaneously into the
patient's vasculature (e.g., into a peripheral artery such as the
femoral artery) and advanced to the implantation site. In certain
embodiments, for example, the catheter is sized for insertion
through a small incision in the groin and has a length of at least
about 80 cm, usually about 90-100 cm, to allow transluminal
positioning of the shaft from the femoral and iliac arteries to the
ascending aorta in a retrograde approach. Alternatively, the
catheter may have a shorter length, e.g. about 20-60 cm, for
introduction through other insertion points, such as, for example,
the iliac artery, the brachial artery, the carotid or the
subclavian arteries. In the femoral approach, the catheter
desirably is long enough and flexible enough to traverse the path
through the femoral artery, iliac artery, descending aorta and
aortic arch. At the same time, the catheter desirably has
sufficient pushability to be advanced to the ascending aorta by
pushing on the proximal end, and has sufficient axial, bending, and
torsional stiffness to allow the physician to control the position
of the distal end, even when the catheter is in a tortuous vascular
structure. Alternatively, the catheter may be passed through a port
between ribs. In one technique, the catheter is advanced through
the patient's thorax above the heart and through an incision in the
aortic arch, in a so-called minimally-invasive procedure. In
another technique, the catheter is advanced through an incision in
the heart wall, preferably along the apex of the heart. The
prosthetic device is advanced to the heart valve that is to be
treated, and it is positioned to extend across the valve with the
arms of the device interposed between the leaflets such that the
leaflets of the valve close and press against the walls of the
insert member to create a tight seal.
[0078] In certain embodiments, the delivery catheter includes an
elongated sheath having a lumen sized to receive the prosthetic
device. The prosthetic device is held within the sheath in a
collapsed configuration during advancement through the subject's
vasculature. For example, during advancement to the left ventricle,
the device is initially contained within the delivery sheath with
the anchoring member retained in a radially compressed state. In
one variation, the distal portion of the delivery sheath is
configured for retrograde advancement and may be configured with a
deflectable end portion for facilitating navigation around the
aortic arch. After reaching the treatment site, the sheath is moved
proximally relative to the prosthetic device to eject the device
from the sheath. The device is then allowed to expand such that the
insert conforms to the gaps in the aortic valve and the anchoring
member engages the inner wall of the aorta.
[0079] Although embodiments of the present invention are preferably
configured for percutaneous or minimally-invasive delivery
procedures, in certain situations, the insert member may be
deployed via an open-heart surgical procedure. In these
embodiments, a delivery catheter may not be necessary since the
defective native valve can be directly accessed.
[0080] Although the disclosure has been described in terms of
particular embodiments and applications, one of ordinary skill in
the art, in light of this teaching, can generate additional
embodiments and modifications without departing from the spirit of
or exceeding the scope of the claimed invention. Accordingly, it is
to be understood that the drawings and descriptions herein are
proffered by way of example to facilitate comprehension of the
disclosure and should not be construed to limit the scope
thereof.
* * * * *