U.S. patent application number 11/112757 was filed with the patent office on 2006-02-02 for implantable prosthetic valve.
Invention is credited to Bjarne Bergheim, Jeff DuMontelle, Keith E. Meyers, Christine Nguyen.
Application Number | 20060025857 11/112757 |
Document ID | / |
Family ID | 35197451 |
Filed Date | 2006-02-02 |
United States Patent
Application |
20060025857 |
Kind Code |
A1 |
Bergheim; Bjarne ; et
al. |
February 2, 2006 |
Implantable prosthetic valve
Abstract
The present invention provides valve prostheses adapted to be
initially crimped in a narrow configuration suitable for
catheterization through body ducts to a target location and adapted
to be deployed by exerting substantially radial forces from within
by means of a deployment device to a deployed state in the target
location.
Inventors: |
Bergheim; Bjarne; (Laguna
Hills, CA) ; Meyers; Keith E.; (Lake Forest, CA)
; DuMontelle; Jeff; (Irvine, CA) ; Nguyen;
Christine; (Garden Grove, CA) |
Correspondence
Address: |
JONES DAY
555 SOUTH FLOWER STREET FIFTIETH FLOOR
LOS ANGELES
CA
90071
US
|
Family ID: |
35197451 |
Appl. No.: |
11/112757 |
Filed: |
April 22, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60565118 |
Apr 23, 2004 |
|
|
|
Current U.S.
Class: |
623/2.18 |
Current CPC
Class: |
A61L 27/3882 20130101;
A61F 2/04 20130101; A61F 2002/0086 20130101; A61F 2250/0098
20130101; A61F 2/2409 20130101; A61F 2250/0069 20130101; A61F
2210/0014 20130101; A61F 2230/0054 20130101; A61L 2430/20 20130101;
A61F 2220/0075 20130101; A61F 2220/0041 20130101; A61L 27/18
20130101; A61L 27/507 20130101; A61L 27/26 20130101; A61L 27/50
20130101; A61F 2/0077 20130101; A61L 27/3804 20130101; A61F
2220/005 20130101; A61F 2230/0013 20130101; A61L 27/047 20130101;
A61F 2230/0069 20130101; A61F 2/2418 20130101 |
Class at
Publication: |
623/002.18 |
International
Class: |
A61F 2/24 20060101
A61F002/24 |
Claims
1. A prosthetic valve assembly comprising: (a) a valve having an
inlet end and an outlet made of pliant material arranged so as to
present collapsible walls at the outlet; and (b) a support
structure adapted to be positioned at a target location within the
body duct and deploy the valve assembly by the use of deploying
means.
Description
[0001] This application claims the benefit of U.S. Provisional
Application No. 60/565,118, filed Apr. 23, 2004.
FIELD OF THE INVENTION
[0002] The present invention relates to implantable devices. More
specifically, the present invention relates to heart valve
prosthetic devices for cardiac implantation. The present invention
may also be utilized in other body cavities, vessels, or ducts.
BACKGROUND OF THE INVENTION
[0003] The transport of vital fluids in the human body is largely
regulated by valves. Physiological valves are designed to prevent
the backflow of bodily fluids, such as blood, lymph, urine, bile,
etc., thereby keeping the body's fluid dynamics unidirectional for
proper homeostasis. For example, venous valves maintain the upward
flow of blood, particularly from the lower extremities, back toward
the heart, while lymphatic valves prevent the backflow of lymph
within the lymph vessels, particularly those of the limbs.
[0004] Because of their common function, valves share certain
anatomical features despite variations in relative size. The
cardiac valves are among the largest valves in the body with
diameters that may exceed 30 mm, while valves of the smaller veins
may have diameters no larger than a fraction of a millimeter.
Regardless of their size, however, many physiological valves are
situated in specialized anatomical structures known as sinuses.
Valve sinuses can be described as dilations or bulges in the vessel
wall that houses the valve. The geometry of the sinus has a
function in the operation and fluid dynamics of the valve. One
function is to guide fluid flow so as to create eddy currents that
prevent the valve leaflets from adhering to the wall of the vessel
at the peak of flow velocity, such as during systole. Another
function of the sinus geometry is to generate currents that
facilitate the precise closing of the leaflets at the beginning of
backflow pressure. The sinus geometry is also important in reducing
the stress exerted by differential fluid flow pressure on the valve
leaflets or cusps as they open and close.
[0005] Thus, for example, the eddy currents occurring within the
sinuses of Valsalva in the natural aortic root have been shown to
be important in creating smooth, gradual and gentle closure of the
aortic valve at the end of systole. Blood is permitted to travel
along the curved contour of the sinus and onto the valve leaflets
to effect their closure, thereby reducing the pressure that would
otherwise be exerted by direct fluid flow onto the valve leaflets.
The sinuses of Valsalva also contain the coronary ostia, which are
outflow openings of the arteries that feed the heart muscle. When
valve sinuses contain such outflow openings, they serve the
additional purpose of providing blood flow to such vessels
throughout the cardiac cycle.
[0006] When valves exhibit abnormal anatomy and function as a
result of valve disease or injury, the unidirectional flow of the
physiological fluid they are designed to regulate is disrupted,
resulting in increased hydrostatic pressure. For example, venous
valvular dysfunction leads to blood flowing back and pooling in the
lower legs, resulting in pain, swelling and edema, changes in skin
color, and skin ulcerations that can be extremely difficult to
treat. Lymphatic valve insufficiency can result in lymphedema with
tissue fibrosis and gross distention of the affected body part.
Cardiac valvular disease may lead to pulmonary hypertension and
edema, atrial fibrillation, and right heart failure in the case of
mitral and tricuspid valve stenosis; or pulmonary congestion, left
ventricular contractile impairment and congestive heart failure in
the case of mitral regurgitation and aortic stenosis. Regardless of
their etiology, all valvular diseases result in either stenosis, in
which the valve does not open properly, impeding fluid flow across
it and causing a rise in fluid pressure, or
insufficiency/regurgitation, in which the valve does not close
properly and the fluid leaks back across the valve, creating
backflow. Some valves are afflicted with both stenosis and
insufficiency, in which case the valve neither opens fully nor
closes completely.
[0007] Because of the potential severity of the clinical
consequences of valve disease, valve replacement surgery is
becoming a widely used medical procedure, described and illustrated
in numerous books and articles. When replacement of a valve is
necessary, the diseased or abnormal valve is typically cut out and
replaced with either a mechanical or tissue valve. A conventional
heart valve replacement surgery involves accessing the heart in a
patient's thoracic cavity through a longitudinal incision in the
chest. For example, a median sternotomy requires cutting through
the sternum and forcing the two opposite halves of the rib cage to
be spread apart, allowing access to the thoracic cavity and the
heart within. The patient is then placed on cardiopulmonary bypass,
which involves stopping the heart to permit access to the internal
chambers. Such open heart surgery is particularly invasive and
involves a lengthy and difficult recovery period. Reducing or
eliminating the time a patient spends in surgery is thus a goal of
foremost clinical priority.
[0008] One strategy for reducing the time spent in surgery is to
eliminate or reduce the need for suturing a replacement valve into
position. Toward this end, valve assemblies that allow implantation
with minimal or no sutures would be greatly advantageous. Attaching
a valve such as a tissue valve to a support structure such as a
stent may enable a valve assembly that allows implantation with
minimal or no sutures. It is important that such valve constructs
are configured such that the tissue leaflets or the support valve
don't come into contact with the support structure, either during
the collapsed or expanded state, or both in order to prevent
abrasion. Such contact is capable of contributing undesired stress
on the valve leaflet. Moreover, it is advantageous that such
support structures are configured to properly support a tissue
valve having a scalloped inflow annulus such as that disclosed in
the U.S. patent application Ser. No. 09/772,526 which is
incorporated by reference herein in its entirety.
[0009] Accordingly, there is a need for a valve replacement system
comprising a collapsible and expandable valve assembly that is
capable of being secured into position with minimal or no suturing;
facilitating an anatomically optimal position of the valve;
maintaining an open pathway for other vessel openings of vessels
that may be located in the valvular sinuses; and minimizing or
reducing stress to the tissue valve leaflets. The valves of the
present invention may comprise a plurality of joined leaflets with
a corresponding number of commissural tabs. Generally, however, the
desired valve will contain two to four leaflets and commissural
tabs. Examples of other suitable valves are disclosed in U.S.
patent application Ser. Nos. 09/772,526, 09/853,463, 09/924,970,
10/121,208, 10/122,035, 10/153,286, 10/153,290, the disclosures of
all of which are incorporated by reference in their entirety
herein. Likewise, the systems and methods disclosed in U.S. patent
application Ser. No. 10/831,770, filed Apr. 23, 2004, are fully
incorporated by reference herein.
[0010] As mentioned above, an open-heart valve replacement is a
long tedious procedure. For implantation of a bioprosthetic valve
in the aortic position, a surgeon typically opens the aorta and
excises the native valve. The surgeon then inserts the prosthetic
valve through the opening in the aortic wall and secures the
prosthesis at the junction of the aorta and the left ventricle. The
inflow annulus of the valve faces the left ventricle and, relative
to the surgeon's perspective, may be termed the distal annulus,
while the outflow annulus of the valve faces the aorta and may be
termed the proximal annulus.
[0011] An alternative procedure for approaching the left atrium and
the aortic or mitral valve is by intravascular catherization from a
femoral vein through the cardiac septum, which separates the right
atrium and the left atrium. Yet another alternative for approaching
the left atrium and the aortic or mitral valve is by intravascular
catherization from a femoral artery up through aortic valve.
[0012] Andersen et al. in U.S. Pat. No. 6,582,462, entire contents
of which are incorporated herein by reference, discloses a valve
prosthesis for implantation in a body channel having an inner wall,
the prosthesis comprising a radially collapsible and expandable
cylindrical stent, the stent including a cylindrical support means
having a cylinder surface; and a collapsible and expandable valve
having commissural points, the valve mounted to the stent at the
commissural points, wherein the stent and valve are configured to
be implanted in the body by way of catheterization. It is one
aspect of the present invention to utilize a balloon expandable
stent coupled with a tissue valve. An alternative embodiment in the
present invention to utilizing a balloon expandable stent is to
utilize a self-expandable stent. Yet another alternative embodiment
of the present invention to utilizing a balloon expandable stent is
to utilize a stent that may be expanded with mechanical means.
[0013] Sterman et al. in U.S. Pat. No. 6,283,127, entire contents
of which are incorporated herein by reference, discloses a device
system and methods facilitating intervention within the heart or
great vessels without the need for a median sternotomy or other
form of gross thoracotomy, substantially reducing trauma, risk of
complication, recovery time, and pain for the patient. Using the
device systems and methods of the invention, surgical procedures
may be performed through percutaneous penetrations within
intercostal spaces of the patient's rib cage, without cutting,
removing, or significantly displacing any of the patient's ribs or
sternum. The device systems and methods are particularly well
adapted for heart valve repair and replacement, facilitating
visualization within the patient's thoracic cavity, repair or
removal of the patient's natural valve, and, if necessary,
attachment of a replacement valve in the natural valve
position.
[0014] Haluck in U.S. Pat. No. 6,685,724, entire contents of which
are incorporated herein by reference, discloses a surgical
instrument for use in performing endoscopic procedures having a
handle and an elongate tubular member having a proximal end coupled
with the handle for being disposed externally of the anatomical
cavity and a distal end for being disposed within the anatomical
cavity. The distal end further includes a pair of opposed,
relatively movable jaws that form a grasping portion operable by
manipulation of the handle to releasably grasp a releasable trocar.
The releasable trocar has a complementarily shaped shank, a
relatively sharp tip and may include a pair of blunt-edge tissue
separators that project outwardly from the outer surface of the
trocar.
[0015] Endoscopic and minimally invasive medical procedures, such
as laparoscopy, have become widely accepted for surgery and illness
diagnosis. This is due to reduced trauma to the patient and reduced
hospitalization time. Other techniques exist for creating a working
space within the body cavity. At the beginning of most laparoscopic
cases, a small incision is made, followed by a small (about 1 cm)
port in the remaining layers of the tissue wall so as to gain
access to the cavity.
[0016] Hunsberger in U.S. Pat. No. 6,613,063, entire contents of
which are incorporated herein by reference, discloses a trocar
assembly which includes a shank having a distal end and a proximal
end, and a planar piercing blade having two substantially flat
faces and a cutting contour, where the piercing blade is integrally
attached to the distal end of the shank. The shank tapers inwardly
towards the opposed flat faces of the piercing blade.
[0017] Further, McFarlane in U.S. Pat. No. 6,478,806, entire
contents of which are incorporated herein by reference, discloses a
tissue penetrating instrument of the type used in the medical field
and which may or may not be embodied in the form of an obturator
associated with a trocar assembly, wherein the instrument includes
an elongated shaft having a penetrating tip mounted on one end
thereof. The penetrating tip includes a base secured to the one end
of the shaft and a distal extremity spaced longitudinally outward
from the base and formed into an apex which may be defined by a
point or other configuration specifically structured to facilitate
penetration or puncturing of bodily tissue.
[0018] Spenser et al. disclose in U.S. patent application Ser. Nos.
09/975,750, 10/270,252, and 10/637,882, entire contents of which
are incorporated herein by reference, disclose and implantable
prosthetic valve that comprises a support sent to be initially
crimped in a narrow configuration suitable for catherization
through the body duct to a target location.
[0019] Key features of any valve where sutures to hold the
replacement valve into position are to be eliminated or reduced
are: durability, low-pressure gradient across the valve, sufficient
seal around the valve to prevent perivalvular leak, and prevent
migration. Therefore, it would be desirable to provide an
implantable valve that with features that aim to increase
durability, reduce pressure gradient across the valve, and provide
an adequate seal around the valve and prevent migration.
SUMMARY OF THE INVENTION
[0020] The present invention provides a valve prosthesis that in
one embodiment comprises a support stent, comprised of a deployable
construction adapted to be initially crimped in a narrow
configuration suitable for catherization through the body ducts to
a target location and adapted to be deployed by exerting
substantially radial forces from within by means of a deployment
device to a deployed state in the target location, the support
stent provided with a plurality of longitudinally rigid support
beams of fixed length; and a valve assembly comprising a flexible
conduit having an inlet end and an outlet, made of pliant material
attached to the support beams providing collapsible slack portions
of the conduit at the outlet, whereby when flow is allowed to pass
through the valve prosthesis device from the inlet to the outlet
the valve assembly is kept in an open position whereas a reverse
flow is prevented as the collapsible slack portions of the valve
assembly collapse inwardly providing blockage to the reverse
flow.
[0021] In another embodiment of the present invention, the support
stent comprises an annular frame.
[0022] In yet another embodiment of the present invention, the
support stent is made out of stainless steel.
[0023] In yet another embodiment of the present invention, said
valve assembly has a tricuspid configuration.
[0024] In yet another embodiment of the present invention, said
valve assemblyis made from biocompatible material.
[0025] In yet another embodiment of the present invention, the
valve assembly is made from pericardial tissue, or other biological
tissue.
[0026] In yet another embodiment of the present invention, said
valve assembly is made from biocompatible polymers.
[0027] In yet another embodiment of the present invention, the
valve assembly is made from materials selected from the group
consisting of polyurethane and polyethylene terphthalane.
[0028] In yet another embodiment of the present invention, the
valve assembly comprises a main body made from polyethylene
terphthalane and leaflets made from polyurethane.
[0029] In yet another embodiment of the present invention, said
support stent is made from nickel titanium alloys.
[0030] In yet another embodiment of the present invention, the
support beams are substantially equidistant and substantially
parallel so as to provide anchorage for the valve assembly.
[0031] In yet another embodiment of the present invention, the
support beams are provided with bores so as to allow stitching or
tying of the valve assembly to the beams.
[0032] In yet another embodiment of the present invention, the
support beams are not provided with bores so as to allow extra
rigidity to the valve support structures.
[0033] In yet another embodiment of the present invention, the
support beams are chemically adhered to the support stent.
[0034] In yet another embodiment of the present invention, said
valve assembly is riveted to the support beams.
[0035] In yet another embodiment of the present invention, said
beams are manufactured by injection using a mold, or by
machining.
[0036] In yet another embodiment of the present invention, said
valve assembly is rolled over the support stent at the inlet.
[0037] In yet another embodiment of the present invention, said
valve device is manufactured using forging or dipping
techniques.
[0038] In yet another embodiment of the present invention, said
valve assembly leaflets are longer than needed to exactly close the
outlet, thus when they are in the collapsed state substantial
portions of the leaflets fall on each other creating better
sealing.
[0039] In yet another embodiment of the present invention, said
valve assembly is made from coils of a polymer, coated by a coating
layer of same polymer.
[0040] In yet another embodiment of the present invention, said
polymer is polyurethane.
[0041] In yet another embodiment of the present invention, the
support stent is provided with heavy metal markers so as to enable
tracking and determining the valve device position and
orientation.
[0042] In yet another embodiment of the present invention, the
heavy metal markers are selected from gold, platinum, iridium,
tantalum, cobalt, chrome, and titanium alloys.
[0043] In yet another embodiment of the present invention, the
valve assembly leaflets are provided with radio-opaque materials at
the outlet so as to help tracking the valve device operation in
vivo.
[0044] In yet another embodiment of the present invention, said
radio0opque material comprises gold thread.
[0045] In yet another embodiment of the present invention, the
diameter of said support stent when fully deployed is in the range
of from about 15 to about 33 mm.
[0046] In yet another embodiment of the present invention, the
diameter of said support stent may be expanded from about 4 to
about 25 mm.
[0047] In yet another embodiment of the present invention, the
diameter of said support stent may be expanded from about 10 mm to
about 25 mm.
[0048] In yet another embodiment of the present invention, the
support beams are provided with bores and wherein the valve
assembly is attached to the support beams by means of U-shaped
rigid members that are fastened to the valve assembly and that are
provided with extruding portions that fit into matching bores on
the support beams.
[0049] In yet another embodiment of the present invention, the
support beams comprise rigid support beams in the form of frame
construction, and the valve assembly pliant material is inserted
through a gap in the frame and a fastening rod is inserted through
a pocket formed between the pliant material and the frame and holds
the valve in position.
[0050] In yet another embodiment of the present invention, the main
body of the valve assembly is made from coiled wire coated with
coating material.
[0051] In yet another embodiment of the present invention, the
coiled wire and the coating material is made from polyurethane.
[0052] In yet another embodiment of the present invention, a
strengthening wire is interlaced in the valve assembly at the
outlet of the conduit so as to define a fault line about which the
collapsible slack portion of the valve assembly may flap.
[0053] In yet another embodiment of the present invention, the
strengthening wire is made from nickel titanium alloy.
[0054] In yet another embodiment of the present invention, there is
provided a valve prosthesis device suitable for implantation in
body ducts, the device comprising a main conduit body having an
inlet and an outlet and pliant leaflets attached at the outlet so
that when a flow passes through the conduit from the inlet to the
outlet the leaflets are in an open position allowing the flow to
exit the outlet, and when the flow is reversed the leaflets
collapse so as to block the outlet, wherein the main body is made
from polyethylene terphtalate and collapsible leaflets are made
from polyurethane.
[0055] In yet another embodiment of the present invention, support
beams made from polyurethane are provided on the main body and
wherein the leaflets are attached to the main body at the support
beams.
[0056] In yet another embodiment of the present invention, said
support beams are chemically adhered to the main body.
[0057] In yet another embodiment of the present invention, there is
provided a valve prosthesis device suitable for implantation in
body ducts, the device comprising:
[0058] A support stent, comprised of a deployable construction
adapted to be initially crimped in a narrow configuration suitable
for catherization through the body duct to a target location and
adapted to be deployed by exerting substantially radial force from
within by means of a deployment device to a deployed state in the
target location, the support stent provided with a plurality of
longitudinally rigid support beams of fixed length; [0059] A valve
assembly comprising a flexible conduit having an inlet and an
outlet, made of pliant material attached to the support beams
providing collapsible slack portions of the conduit at the outlet;
and [0060] Substantially equidistant rigid support beams interlaced
or attached to the slack portion of the valve assembly material,
arranged longitudinally
[0061] In yet another embodiment of the present invention, the
multiple plates are adapted to move simultaneously by means of a
lever and transmission.
[0062] In yet another embodiment of the present invention, there is
provided a method for deploying an implantable prosthesis valve
device at the natural aortic valve position at the entrance to the
left ventricle of a myocardium of a patient, the method comprising
the steps of: [0063] (a) providing a balloon catheter having a
proximal end and a distal end, having a first and second
independently inflatable portions, the first inflatable portion
located at the distal end of the catheter and the second inflatable
portion adjacently behind the first inflatable portion; [0064] (b)
providing a guiding tool for guiding the balloon catheter in the
vasculature of the patient; [0065] (c) providing a deployable
implantable valve prosthesis device adapted to be mounted on the
second inflatable portion of the balloon catheter; [0066] (d)
guiding the balloon catheter through the patient's aorta using the
guiding tool, the valve device mounted over the second inflatable
portion of the balloon catheter until the first inflatable portion
of the balloon catheter is inserted into the left ventricle,
whereas the second inflatable portion of the balloon catheter is
positioned at the natural aortic valve position; [0067] (e)
inflating the first inflatable portion of the balloon catheter so
as to substantially block blood flow through the natural aortic
valve and anchor the distal end of the balloon catheter in
position; [0068] (f) inflating the second inflatable portion of the
balloon catheter so as to deploy the implantable prosthesis valve
device in position at the natural aortic valve positions; [0069]
(g) deflating the first and second inflatable portions of the
balloon catheter; and [0070] (h) retracting the balloon catheter
and removing it from the patient's body.
[0071] In yet another embodiment of the present invention, the
guiding tool compromises a guide wire.
[0072] In some further embodiments, the present invention provides
a method for deploying an implantable prosthesis valve device at
the natural aortic valve position at the entrance to the left
ventricle of the myocardium of a patient, the method comprising the
steps of: [0073] (a) providing a balloon catheter having a proximal
end a distal end, having a first and second independently
inflatable portions, the first inflatable portion located at the
distal end of the catheter and the second inflatable portion
adjacently behind the first inflatable portion; [0074] (b)
providing a guiding tool for guiding the balloon catheter in the
vasculature of the patient; [0075] providing a deployable
implantable valve prosthesis device adapted to be mounted on the
first inflatable portion of the balloon catheter, and a deployable
annular stent device adapted to be mounted over the second
inflatable portion of the balloon catheter, the deployable
implantable valve prosthesis device and the deployable annular
stent kept at a predetermined distance apart; [0076] (d) guiding
the balloon catheter through the patient's aorta using the guiding
tool, the valve device mounted over the first inflatable portion of
the balloon catheter and the deployable annular stent mounted over
the second inflatable portion of the balloon catheter, until the
first inflatable portion of the balloon catheter is positioned at
the natural aortic valve position; [0077] (e) inflating the second
inflatable portion of the balloon catheter so that the deployable
stent device is deployed within the aorta thus anchoring the
deployable annular stent and the coupled valve device in position;
[0078] (f) inflating the first inflatable portion of the balloon
catheter so as to deploy the implantable prosthesis valve device in
position at the natural aortic valve position; [0079] (g) deflating
the first and second inflatable portions of the balloon catheter;
and [0080] (h) retracting the balloon catheter and removing it from
the patient's body.
[0081] It is one object of the valve device described in the
present invention to presents a novel means of attaching a tissue
valve to a support structure. The means of attaching the valve to
the support structure may increase the durability of the valve,
reduce the pressure gradient across the valve, provide a seal
around the valve to prevent perivalvular leak, and prevent
migration. The valves of the present invention may comprise a
plurality of joined leaflets with a corresponding number of
commissural tabs. Generally, however, the desired valve will
contain two to four leaflets and commissural tabs.
[0082] In an embodiment of the present invention, the valves are
similar to the valves disclosed in U.S. patent application Ser.
Nos. 09/772,526, 09/853,463, 09/924,970, 10/121,208, 10/122,035,
10/153,286, 10/153,290, the disclosures of all of which are
incorporated by reference in their entirety herein. The diameter of
the valves described in these applications may be equal or less
than the orifice diameter of the support structure of the
valve.
[0083] In yet another embodiment of the present invention, the
valves described in U.S. patent application Ser. Nos. 09/772,526,
09/853,463, 09/924,970, 10/121,208, 10/122,035, 10/153,286,
10/153,290, the valves are sized such that the effective valve
diameter is 1-5 mm less than the diameter of the orifice of the
support structures of the valve. This size will help prevent the
valve leaflets from hitting the support structure.
[0084] In yet another embodiment of the present invention, the
valves are made of equine pericardium.
[0085] In yet another embodiment of the present invention, a cuff
(e.g. cloth) portion of the valve assembly is wrapped around the
support stent at the inlet. This may enhance stability of the
stent, but further, the cuff portion described in the current
invention may be used for attaching sutures. Most importantly, the
cuff portion of the present invention is intended to reduce
perivalvular leak around the valve. Using such a cuff to create a
seal between the valve structure and the aorta prevents
perivalvular leak and is especially important in patients whose
annulus (or landing zone for the valve) is calcified or irregular.
The cuff may also prevent migration of the valve as the friction
between the valve device and the surrounding is increased.
Utilizing a cloth cuff may also induce tissue ingrowth. The cloth
may initially clot when it is exposed to blood. The cloth may
further induce endothelial and fibroblast, and hence tissue
ingrowth into the cloth cuff.
[0086] In yet another embodiment of the present invention the cloth
cuff creates a step between a thin cloth covering around the inlet
portion of the valve assembly that moves up to a much thicker cloth
cuff slightly further downstream in the assembly. Such a "lip" or
"step" may help position and secure the valve prosthesis at the
correct position.
[0087] In yet other embodiments of the present invention, the
scalloped inflow edge described in U.S. application Ser. Nos.
09/772,526, 09/853,463, 09/924,970, 10/121,208, 10/122,035,
10/153,286, 10/153,290, is sutured onto the cuff portion of the
valve assembly described above. Another use of the cuff is thus to
allow a valve with a scalloped inflow edge to be attached to a
non-scalloped stent.
[0088] In yet other embodiments of the present invention, the
support beams of the stent are extended at the inflow portion to
accommodate the length of longer valves such as the ones described
in U.S. application Ser. Nos. 09/772,526, 09/853,463, 09/924,970,
10/121,208, 10/122,035, 10/153,286, 10/153,290.
[0089] In yet another embodiment of the present invention, the
support beams form eyelets at the outflow edge that the tabs of the
valves described in U.S. application Ser. Nos. 09/772,526,
09/853,463, 09/924,970, 10/121,208, 10/122,035, 10/153,286,
10/153,290 may be attached to. The valve tabs may be sutured to the
eyelets around the perimeter of the eyelet. Such a configuration
helps distribute the stress around the tabs and reduce the wear and
tear on the commissural posts of the valve.
[0090] In yet another embodiment of the present invention, the
support beam eyelets described above are covered with cloth.
Covering the eyelets and tabs with cloth may help induce tissue
ingrowth.
[0091] In yet another embodiment of the present invention, the
valve device is made such that it cannot be crimped down beyond the
diameter of a typical femoral artery or a femoral vein (where the
catheter can typically be no more than 8 mm). In other words, the
valve device is made such that it cannot be implanted through the
femoral artery or femoral vein.
[0092] In yet another embodiment of the present invention, the
valve device is crimped just after it has been manufactured, and
shipped from the manufacturer in the crimped state to the hospital
or where it is to be implanted.
[0093] In yet another embodiment of the present invention, the
stent is made out of a memory shaped metal or a memory shaped
polymer.
[0094] In yet another embodiment of the present invention, the
stent of the valve device is made to be balloon expandable.
[0095] In yet another embodiment of the present invention, the
stent of the valve device is made to be self-expandable.
[0096] The present invention provides systems and devices for the
replacement of physiological valves. In one embodiment of the
present invention, the replacement valve assemblies are adapted to
fit substantially within the valve sinuses. Because the devices and
procedures provided by the present invention eliminate or reduce
the need for suturing, time spent in surgery is significantly
decreased, and the risks associated with surgery are minimized.
Further, the devices of the present invention are suitable for
delivery by cannula or catheter.
[0097] In yet another embodiment of the present invention, the
stent of the valve device is made such as to expand into the sinus
regions during balloon expansion.
[0098] In yet another embodiment of the present invention, the
stent of the valve devices is made such as to expand into the sinus
region during self-expansion.
[0099] In one embodiment of the present invention a valve anchoring
structure is provided that is dimensioned to be placed
substantially within the valve sinus. In this embodiment, the valve
anchoring structure extends substantially across the length of the
valve sinus region.
[0100] In another embodiment of the present invention a valve
assembly is provided, comprising a valve and anchoring structure,
in which the valve comprises a body having a proximal end and a
distal end, an inlet at the proximal end, and an outlet at the
distal end. The inlet comprises an inflow annulus, with either a
scalloped or straight edge. The outlet comprises a plurality of
tabs that are supported by the anchoring means at the distal end.
In an embodiment of the invention, the plurality of tabs is spaced
evenly around the circumference of the valve.
[0101] In yet another embodiment of the present invention, a valve
assembly is provided in which there is minimal or no contact
between the valve and anchoring structure.
[0102] In still another embodiment of the present invention, a
valve assembly is provided in which the valve is capable of
achieving full opening and full closure without contacting the
anchoring structure.
[0103] In yet another embodiment of the present invention, a valve
assembly is provided in which the vertical components of the
anchoring structure are limited to the commissural posts between
sinus cavities, thereby minimizing contact between mechanical
components and fluid, as well as providing flow to vessels located
in the valve sinus.
[0104] In still another embodiment of the present invention, a
valve is provided that firmly attaches to the valve sinus,
obviating the need for suturing to secure the valve placement.
[0105] In a further embodiment of the present invention, a valve
assembly is provided in which the anchoring structure may be
collapsed to at least fifty percent of its maximum diameter.
[0106] In still a further embodiment of the present invention, an
expansion and contraction device is provided to facilitate
implantation of the valve and anchoring structure.
[0107] In another embodiment, the present invention provides
adhesive means for securing the valve assembly in a valve
sinus.
[0108] In yet another embodiment of the present invention, a valve
sizing apparatus is provided for the noninvasive determination of
native valve size.
BRIEF DESCRIPTION OF THE DRAWINGS
[0109] To better understand the present invention and appreciate
its practical applications, the following Figures are provided and
referenced hereafter. It should be noted that the Figures are given
as examples only and in no way limit the scope of the
invention.
[0110] FIG. 1 shows the valve structure, stent, or frame seen from
the side.
[0111] FIG. 2 shows the valve structure, stent, or frame seen from
the side.
[0112] FIG. 3 shows the valve structure, stent, or frame seen from
an isometric view.
[0113] FIG. 4 shows the valve structure, stent, or frame seen from
the top (i.e. at the outflow side).
[0114] FIG. 5 shows the frame with a cloth cover around the inflow
edge.
[0115] FIG. 6 shows the frame with a cloth cover around the inflow
edge.
[0116] FIG. 7 shows the frame with cloth cover around the inflow
edge.
[0117] FIG. 8 shows the frame with cloth cover around the inflow
edge.
[0118] FIG. 9 shows the frame with cloth cover around the inflow
edge. The valve is also attached in this figure. The tabs of the
valve are aligned with the eyelets of the frame.
[0119] FIG. 10 shows the frame with cloth cover around the inflow
edge. The valve is also attached in this figure. The tabs of the
valve are aligned with the eyelets of the frame.
[0120] FIG. 11 shows the frame with cloth cover around the inflow
edge. The valve is also attached in this figure. The tabs of the
valve are aligned with the eyelets of the frame.
[0121] FIG. 12 shows the frame with cloth cover around the inflow
edge. The valve is also attached in this figure. The tabs of the
valve are aligned with the eyelets of the frame.
[0122] FIG. 13 shows the frame with cloth cover around the inflow
edge. The valve is also attached in this figure. The tabs of the
valve are aligned with the eyelets of the frame. Cloth has been
added and keeps the valve tabs attached to the frame eyelets.
[0123] FIG. 14 shows the frame with cloth cover around the inflow
edge. The valve is also attached in this figure. The tabs of the
valve are aligned with the eyelets of the frame. Cloth has been
added and keeps the valve tabs attached to the frame eyelets.
[0124] FIG. 15 shows the frame with cloth cover around the inflow
edge. The valve is also attached in this figure. The tabs of the
valve are aligned with the eyelets of the frame. Cloth has been
added and keeps the valve tabs attached to the frame eyelets.
[0125] FIG. 16 shows the frame with cloth cover around the inflow
edge. The valve is also attached in this figure. The tabs of the
valve are aligned with the eyelets of the frame. Cloth has been
added and keeps the valve tabs attached to the frame eyelets.
[0126] FIG. 17 shows one of the leaflets described in U.S.
application Ser. Nos. 09/772,526, 09/853,463, 09/924,970,
10/121,208, 10/122,035, 10/153,286, 10/153,290 and shows how this
is aligned with the frame and frame eyelets. The cloth cuff around
the inflow edge has been removed for clarity.
[0127] FIG. 18 shows the outflow side of a prototype valve
prosthesis.
[0128] FIG. 19 shows the inflow side of a prototype valve
prosthesis.
[0129] FIG. 20 shows a side view of a prototype valve
prosthesis.
[0130] FIG. 21 shows the stent of the valve assembly crimped down
to 7.5 mm
[0131] FIG. 22 shows the assembly of the valve tab to frame
eyelet
[0132] FIG. 23 shows final cloth covering of tab/eyelet
assembly.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0133] A main aspect of the present invention is the introduction
of several novel designs for an implantable prosthesis valve.
Another aspect of the present invention is the disclosure of
several manufacture methods for the manufacturing of implantable
prosthesis valves in accordance with the present invention. A
further aspect of the present invention is the provision of novel
deployment and positioning techniques suitable for the valve of the
present invention.
[0134] Basically the implantable prosthetic valve of the present
invention comprises a leafed-valve assembly, preferably tricuspid
but not limited to tricuspid valves only, consisting of a conduit
having an inlet end and an outlet, made of pliant material arranged
so as to present collapsible walls at the outlet. The valve
assembly is mounted on a support structure such as a stent adapted
to be positioned at a target location within the body duct and
deploy the valve assembly by the use of deploying means, such as a
balloon catheter or similar devices. In embodiments suitable for
safe and convenient percutaneous positioning and deployment the
annular frame is able to be posed in two positions, a crimped
position where the conduit passage cross-section presented is small
so as to permit advancing the device towards its target location,
and a deployed position where the frame is radial extended by
forces exerted from within (by deploying means) so as to provide
support against the body duct wall, secure the valve in position
and open itself so as to allow flow through the conduit.
[0135] The valve assembly can be made from biological matter, such
as a natural tissue, pericardial tissue or other biological tissue.
Alternatively, the valve assembly may be made form biocompatible
polymers or similar materials. Homograph biological valves need
occasional replacement (usually within 5 to 14 years) and this is a
consideration the surgeon must take into account, when selecting
the proper valve implant according to the patient type. Metal
mechanical valves, which have better durability qualities, carry
the associated risk of long-term anticoagulation treatment.
[0136] The frame can be made from shape memory alloys such as
nickel titanium (nickel titanium shape memory alloys, or NiTi, as
marketed, for example, under the brand name Nitinol), or other
biocompatible metals. The percutaneously implantable embodiment of
the implantable valve of the present invention has to be suitable
for crimping into a narrow configuration for positioning and
expandable to a wider, deployed configuration so as to anchor in
position in the desired target location.
[0137] The support stent is preferably annular, but may be provided
in other shapes too, depending on the cross-section shape of the
desired target location passage.
[0138] Manufacturing of the implantable prosthetic valve of the
present invention can be done in various methods, for example, by
dipping, injection, electrospinning, rotation, ironing, or
pressing.
[0139] The attachment of the valve assembly to the support stent
can be accomplished in several ways, such as by sewing it to
several anchoring points on the support stent, or riveting it,
pinning it, or adhering it, to provide a valve assembly that is
cast or molded over the support stent, or use any other suitable
way of attachment.
[0140] To prevent leakage from the inlet it is optionally possible
to roll up some slack wall of the inlet over the edge of the frame
so as to present rolled-up sleeve-like portion at the inlet.
[0141] Furthermore, floating supports may be added to enhance the
stability of the device and prevent it from turning inside out.
[0142] An important aspect of certain embodiments of the present
invention is the provision of rigid support beams incorporated with
the support stent that retains its longitudinal dimension while the
entire support stent may be longitudinally or laterally
extended.
[0143] The aforementioned embodiments as well as other embodiments,
manufacturing methods, different designs and different types of
devices are discussed and explained below with reference to the
accompanying drawings. Note that the drawings are only given for
the purpose of understanding the present invention and presenting
some preferred embodiments of the present invention, but this does
in no way limit the scope of the present invention as defined in
the appended claims.
[0144] Reference is now made to FIG. 1, which illustrates a valve
support structure or frame shown in a deployed position. The frame
has an inlet 9 and an outlet side 10. The frame is arranged in a
net-like frame designed to be crimped evenly so as to present a
narrow configuration and be radially deployable so as to extend to
occupy the passage at the target location for implantation in a
body duct. Support beams 3 are provided on annular support stent 2
to provide rigidity and anchorage to the valve. Support beams 3 may
be provided with bores to provide attachment for a valve. In the
current Figure, the support beams are solid as to provide extra
rigidity to the stent. The support beams 3 transition into oval
eyelets 1 at the outflow edge.
[0145] FIGS. 2-4 show the same frame seen in FIG. 1 from different
perspectives.
[0146] Note that the entire valve structure is adapted to be
radially crimped and radially expanded, and this lends to provide
ease of navigation through narrow passages in the vasculature
during positioning of the device and adequate deployment on the
final location. This is made possible by the provision of a
collapsible support stent structure. However, the support beams
always maintain the same length. Because the support beams maintain
the same length, the distance between the inflow edge and the tab
attachments of the valve are maintained during crimping and
expansion. This allows the valve to function properly. In prior art
implantable valve devices the entire support structure changes its
dimensions from its initial first crimped position and final
deployed position, and this means that in the attachment of the
valve assembly to the support structure one must take into
consideration these dimension changes and leave slack material so
that upon deployment of the device the valve assembly does not tear
or deform. In the valve device of the present invention there is no
relative movement between the valve assembly and the support beams
(along the longitudinal central axis of the device). As a result,
the valve device of the present invention acquires greater
durability and is capable of withstanding the harsh conditions
prevailing within the heart. The novel design of the valve device
of the present invention leads to longitudinal strength and
rigidity whereas its collapsible support structure results in
radial flexibility.
[0147] FIG. 5 shows the cloth cuff (4 and 5) at the inflow edge of
the stent. The cloth cuff may consist of a thin cloth cuff 5 and a
thicker cloth cuff 4 and thus create a lip 11 at the intersection
between these two cuffs. This "lip" or "step" may help position and
secure the valve prosthesis at the correct position. It may, for
example, help hold the valve prosthesis at the inflow annulus when
placed in the aortic position.
[0148] FIGS. 6-8 show the same frame and tissue cuffs seen in FIG.
5 from different perspectives.
[0149] FIG. 9 shows one of the valves 6 disclosed in U.S. patent
application Ser. Nos. 09/772,526, 09/853,463, 09/924,970,
10/121,208, 10/122,035, 10/153,286, 10/153,290. The tabs 7 of the
valve are aligned with the eyelets 1 of the support beams. The
overall size of the eyelets 1 match the size of the tabs 7. The
valve 6 is attached at the inflow side of the frame 9 and is
sutured to the cloth cuff 5 and 4.
[0150] FIGS. 10-12 show the same valve assembly seen in FIG. 9 from
different perspectives.
[0151] FIG. 13 shows the complete valve assembly. In this Figure,
the tabs 7 and the eyelets 1 have been covered with cloth 8.
Covering the tabs 7 with a cloth cuff may induce tissue ingrowth.
The cloth may initially clot when it is exposed to blood. The cloth
may further induce endothelial and fibroblast, and hence tissue
ingrowth. Inducing tissue ingrowth will reduce the loads imposed on
the stent. Covering the tabs 7 and the eyelets 1 with cloth 8 in
this manner will also help distribute the load seen by the
commissural posts across the entire tab, hence reducing wear and
tear on the commissural posts of the valve.
[0152] FIGS. 14-16 show the same valve assembly seen in FIG. 13
from different perspectives.
[0153] FIG. 17 shows one of the leaflets 12 described in U.S.
application Ser. Nos. 09/772,526, 09/853,463, 09/924,970,
10/121,208, 10/122,035, 10/153,286, 10/153,290 and shows how this
is aligned with the frame 15 and frame eyelets 13. The cloth cuff
around the inflow edge has been removed for clarity. Another
embodiment that is evident in FIG. 17 is how the scalloped edge of
the leaflet 14 is positioned relative to the inlet of the stent
15.
[0154] FIGS. 18-20 show pictures of a prototype valve that has been
assembled.
[0155] FIG. 21 shows a picture of a stent crimped to 7.5 mm.
[0156] FIG. 22 shows the assembly of the valve tab to frame
eyelet.
[0157] FIG. 23 shows the final cloth covering of tab/eyelet
assembly.
[0158] A typical size of an aortic prosthesis valve is from about
19 to about 31 mm in diameter. A maximal size of a catheter
inserted into the femoral artery should be no more than 8 mm in
diameter. The present invention introduces a device, which has the
ability to change its diameter from about 4 mm to about 33 mm.
Artificial valves are not new; however, artificial valves in
accordance with the present invention posses the ability to change
shape and size for the purpose of delivery and as such are novel.
These newly designed valves require new manufacturing methods and
technical inventions and improvements, some of which were described
herein.
[0159] As described before, one embodiment of the present invention
is to make it impossible for the stent to be crimped down below the
size of the femoral artery or vein. In other words, one may create
mechanical stops or add tissue or cloth in a manner as to prevent
the stent from being capable of being crimped further down than
beyond the size of the femoral artery or vein. In this manner, the
stent is made such that it intentionally cannot be used through a
femoral vein or femoral artery access. Creating such size
constraints on the valve assembly may make it possible to create a
sturdier device for prolonging the longevity of the valve assembly.
Such a device could be implanted through the apex of the heart, as
described in details in a U.S. patent application submitted Apr.
23, 2004 entitled "Method and System for Cardiac Valve Delivery".
An early version of this document is submitted at the same time as
the current provisional. No application number exists at this
point. The application is appended to this provisional patent
application, and is hereby included in this application in its
entirety.
[0160] As mentioned earlier, the material of which the valve is
made from can be either biological or artificial. In any case new
technologies are needed to create such a valve.
[0161] To attach the valve to the body, the blood vessels determine
the size during delivery, and the requirements for it to work
efficiently, there is a need to mount it on a collapsible
construction which can be crimped to a small size, be expanded to a
larger size, and be strong enough to act as a support for the valve
function. This construction, which is in somewhat similar to a
large "stent", can be made of different materials such as Nitinol,
biocompatible stainless steel, polymeric material or a combination
of all. Special requirement for the stent are a subject of some of
the embodiments discussed herein.
[0162] The mounting of the valve onto a collapsible stent is a new
field of problems. New solutions to this problem are described
herein.
[0163] Another major aspect of the design of the valve of the
present invention is the attachment to the body.
[0164] Yet another major aspect of the valve apparatus is the
attachment of the valve to the frame.
[0165] In the traditional procedure the valve is sutured in place
by a complicated suturing procedure. In the case of the
percutaneous procedure there is no direct access to the
implantation site therefore different attachment techniques are
needed.
[0166] Another new problem that is dealt herein is the delivery
procedure, which is new and unique. Positioning of the device in
the body in an accurate location and orientation requires special
marking and measuring methods of the device and surgical site as
was disclosed herein.
[0167] Artificial polymer valves require special treatment and
special conditions when kept on a shelf, as well as a special
sterilization procedure. One of the consequences of the shelf
treatment is the need to crimp the valve during the implantation
procedure. A series of devices and inventions to allow the crimping
procedure are disclosed herein.
[0168] It should be clear that the description of the embodiments
and attached Figures set forth in this specification serves only
for a better understanding of the invention, without limiting its
scope as covered by the following claims.
* * * * *