U.S. patent application number 12/771546 was filed with the patent office on 2011-02-10 for methods and conduits for flowing blood from a heart chamber to a blood vessel.
This patent application is currently assigned to JenaValve Technology, Inc.. Invention is credited to David Phelps, Peter Wilk, Scott Wolf.
Application Number | 20110034853 12/771546 |
Document ID | / |
Family ID | 26796421 |
Filed Date | 2011-02-10 |
United States Patent
Application |
20110034853 |
Kind Code |
A2 |
Wilk; Peter ; et
al. |
February 10, 2011 |
METHODS AND CONDUITS FOR FLOWING BLOOD FROM A HEART CHAMBER TO A
BLOOD VESSEL
Abstract
Disclosed is a conduit that provides a bypass around an
occlusion or stenosis in a coronary artery. The conduit is a tube
adapted to be positioned in the heart wall to provide a passage for
blood to flow between a heart chamber and a coronary artery, at a
site distal to the occlusion or stenosis. The conduit has a section
of blood vessel attached to its interior lumen which preferably
includes at least one naturally occurring one-way valve positioned
therein. The valve prevents the backflow of blood from the coronary
artery into the heart chamber.
Inventors: |
Wilk; Peter; (New York,
NY) ; Phelps; David; (Louisville, KY) ; Wolf;
Scott; (Minneapolis, MN) |
Correspondence
Address: |
FINNEGAN, HENDERSON, FARABOW, GARRETT & DUNNER;LLP
901 NEW YORK AVENUE, NW
WASHINGTON
DC
20001-4413
UNITED STATES
202-408-4000
|
Assignee: |
JenaValve Technology, Inc.
1000 N. West Street, Suite 1200
Wilmington
DE
19801
|
Prior
Publication: |
|
Document Identifier |
Publication Date |
|
US 20100210991 A1 |
August 19, 2010 |
|
|
Family ID: |
26796421 |
Appl. No.: |
12/771546 |
Filed: |
April 30, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
12/149,901 |
Jun 15, 2010 |
7736327 |
|
|
12771546 |
Apr 30, 2010 |
|
|
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10/928,190 |
Apr 27, 2010 |
7704222 |
|
|
12/149,901 |
May 9, 2008 |
|
|
|
09/828,794 |
Apr 19, 2005 |
6881199 |
|
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10/928,190 |
Aug 30, 2004 |
|
|
|
09/369,061 |
Jul 3, 2001 |
6254564 |
|
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09/828,794 |
Apr 10, 2001 |
|
|
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60/099,719 |
Sep 10, 1998 |
|
|
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Current U.S.
Class: |
604/9 |
Current CPC
Class: |
A61F 2/90 20130101; A61F
2/91 20130101; A61F 2/2493 20130101; A61F 2/94 20130101; A61F 2/82
20130101; A61F 2/958 20130101; A61F 2/962 20130101; A61F 2/848
20130101; A61M 2210/125 20130101; A61M 27/002 20130101 |
Class at
Publication: |
604/009 |
International
Class: |
A61M 1/00 20060101
A61M001/00 |
Claims
1-35. (canceled)
36. A method of treatment, comprising: placing a conduit adjacent a
left ventricle and an arterial blood-containing vessel such that
upon implantation of the conduit a first end of the conduit is
continuously open towards the left ventricle, a second end of the
conduit is continuously open towards and positioned in the arterial
blood-containing vessel, and at least a portion of the first open
end faces at least a portion of the second open end; wherein the
conduit includes a substantially lattice structure adjacent each of
the first and second ends and extending therebetween and wherein a
valve is attached to the conduit within an interior of the conduit
between the first and second ends to control a backflow of blood
from the arterial blood-containing vessel to the left ventricle
during diastole.
37. The method of claim 36, further including enlarging an opening
between the left ventricle and the arterial blood-containing vessel
and thereafter placing the conduit within the opening.
38. The method of claim 36, further including placing the conduit
onto a catheter so that the conduit is in a compressed state, and
introducing the catheter into an aorta.
39. The method of claim 38, further including introducing the
catheter into a femoral artery before introducing the catheter into
an aorta.
40. The method of claim 36, further including placing the conduit
onto a catheter so that the conduit is in a compressed state, and
introducing the catheter into a vein.
41. The method of claim 36, wherein the valve is an aortic
valve.
42. The method of claim 36, wherein the valve is formed from tissue
engineering techniques.
43. The method of claim 36, wherein the first end is a distalmost
end of the conduit and the second end is a proximalmost end of the
conduit, and each of the distalmost and the proximalmost ends is
expandable.
44. The method of claim 36, wherein upon implantation of the
conduit the first end of the conduit is positioned in the left
ventricle.
45. The method of claim 36, wherein the conduit is a metal
conduit.
46. The method of claim 36, wherein the conduit is a plastic
conduit.
47. The method of claim 36, wherein a section of tissue is further
attached within the interior of the conduit adjacent the first
end.
48. A method of treatment, comprising: placing a conduit adjacent a
left ventricle and an arterial blood-containing vessel such that
upon implantation a first end of the conduit is continuously open
towards the left ventricle, a second end of the conduit is
continuously open towards and positioned in the arterial
blood-containing vessel, and a substantially straight line
intersects at least a portion of the first end and at least a
portion of the second end; wherein the conduit includes a
substantially lattice structure adjacent each of the first and
second ends and extending therebetween and wherein a valve is
attached to the conduit within an interior of the conduit between
the first and second ends to control a backflow of blood from the
arterial blood-containing vessel toward the left ventricle during
diastole.
49. The method of claim 48, further including placing the conduit
onto a catheter so that the conduit is in a compressed state, and
introducing the catheter into an aorta.
50. The method of claim 49, further including introducing the
catheter into a femoral artery before introducing the catheter into
an aorta.
51. The method of claim 48, further including placing the conduit
onto a catheter so that the conduit is in a compressed state, and
introducing the catheter into a vein.
52. The method of claim 48 further including enlarging an opening
between the left ventricle and the arterial blood-containing vessel
and thereafter placing the conduit within the opening.
53. The method of claim 48, wherein the first end is a distalmost
end of the conduit and the second end is a proximalmost end of the
conduit, and each of the distalmost and the proximalmost ends is
expandable.
54. The method of claim 53, wherein upon implantation of the
conduit the first end of the conduit is positioned in the left
ventricle.
55. The method of claim 53, wherein the valve is an aortic
valve.
56. The method of claim 53, wherein the valve is formed from tissue
engineering techniques.
57. The method of claim 53, wherein the conduit is a metal
conduit.
58. The method of claim 53, wherein the conduit is a plastic
conduit.
59. The method of claim 53, wherein a section of tissue is further
attached within the interior of the conduit adjacent the first
end.
60. The method of claim 48, wherein the conduit includes a
longitudinal axis that is substantially straight between the first
and second ends.
61. A method of treatment, comprising: introducing a catheter into
an aorta, wherein a conduit having a tissue valve attached to the
conduit is coupled to the catheter so that the conduit and valve
are each in a compressed state; implanting the conduit adjacent a
left ventricle and an arterial blood-containing vessel such that
upon implantation a distalmost end of the conduit is continuously
open towards the left ventricle, a proximalmost end of the conduit
is continuously open towards and positioned in the arterial
blood-containing vessel, and at least a portion of the distalmost
open end faces at least a portion of the proximalmost open end;
wherein the conduit includes a substantially lattice structure
adjacent each of the distalmost and proximalmost ends and extending
therebetween and the valve is attached to the conduit within an
interior of the conduit between the distalmost and proximalmost
ends to control a backflow of blood from the arterial
blood-containing vessel toward the left ventricle during
diastole.
62. The method of claim 61, further including expanding the
distalmost end and the proximalmost end.
63. The method of claim 61, further including enlarging an opening
between the left ventricle and the arterial blood-containing vessel
and thereafter placing the conduit within the opening.
64. The method of claim 61, further including introducing the
catheter into a femoral artery before introducing the catheter into
an aorta.
65. The method of claim 61, wherein upon implantation of the
conduit the distalmost end of the conduit is positioned in the left
ventricle.
66. The method of claim 61, wherein the conduit includes a
substantially straight longitudinal axis and the distalmost and
proximalmost ends intersect the longitudinal axis.
67. The method of claim 61, wherein the valve is an aortic
valve.
68. The method of claim 61, wherein the conduit is a metal
conduit.
69. The method of claim 61, wherein the conduit is a plastic
conduit.
70. The method of claim 61, wherein a section of tissue is further
attached within the interior of the conduit adjacent the first end.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This is a continuation application of U.S. application Ser.
No. 12/149,901, filed May 9, 2008, which is a divisional of U.S.
application Ser. No. 10/928,190, filed Aug. 30, 2004, now U.S. Pat.
No. 7,704,222, which is a continuation of U.S. application Ser. No.
09/828,794, filed Apr. 10, 2001, now U.S. Pat. No. 6,881,199, which
is a continuation of U.S. application Ser. No. 09/369,061, filed
Aug. 4, 1999, now U.S. Pat. No. 6,254,564, which claims the benefit
of U.S. Provisional Application Ser. No. 60/099,719, filed Sep. 10,
1998, the entire disclosures of each being incorporated by
reference herein.
FIELD OF THE INVENTION
[0002] This invention relates to apparatus and method for
implanting a conduit to allow communication of fluids from one
portion of a patient's body to another; and, more particularly, to
a blood flow conduit to allow communication from a heart chamber to
a vessel or vice versa, and/or vessel to vessel. Even more
particularly, the invention relates to a left ventricular conduit
and related conduit configurations having a blood vessel graft
incorporated therein for controlling the flow of blood through the
conduit to achieve bypass of an occluded or stenosed coronary
artery.
BACKGROUND OF THE INVENTION
[0003] Coronary artery disease is a major problem in the U.S. and
throughout the world. Coronary arteries as well as other blood
vessels frequently become clogged with plaque which, at the very
least, can reduce blood and oxygen flow to the heart muscle
(myocardium), and may impair the efficiency of the heart's pumping
action, and can lead to heart attack (myocardial infarction) and
death. In some cases, these coronary arteries can be unblocked
through noninvasive techniques such as balloon angioplasty. In more
difficult cases, a surgical bypass of the blocked vessel is
necessary.
[0004] In a coronary bypass operation, one or more venous segments
are inserted between the aorta and the coronary artery, or,
alternatively, the distal end of an internal mammary artery is
anastomosed to the coronary artery at a site distal to the stenosis
or occlusion. The inserted venous segments or transplants act as a
bypass of the blocked portion of the coronary artery and thus
provide for a free or unobstructed flow of blood to the heart. More
than 500,000 bypass procedures are performed in the U.S. every
year.
[0005] Such coronary artery bypass graft (CABG) surgery, however,
is a very intrusive procedure which is expensive, time-consuming,
and traumatic to the patient. The operation requires an incision
through the patient's sternum (sternotomy), and that the patient be
placed on a heart lung bypass pump so that the heart can be
operated on while not beating. A saphenous vein graft is harvested
from the patient's leg, another highly invasive procedure, and a
delicate surgical procedure is required to piece the bypass graft
to the coronary artery (anastomosis). Hospital stays subsequent to
the surgery and convalescence are prolonged. Furthermore, many
patients are poor surgical candidates due to other concomitant
illnesses.
[0006] As mentioned above, another conventional treatment is
percutaneous transluminal coronary angioplasty (PTCA) or other
types of angioplasty. However, such vascular treatments are not
always indicated due to the type or location of the blockage or
stenosis, or due to the risk of emboli.
[0007] Thus, there is a need for an improved coronary bypass system
which is less traumatic to the patient.
SUMMARY OF THE INVENTION
[0008] The present invention addresses the need in the previous
technology by providing a coronary bypass system which avoids a
sternotomy, and other intrusive aspects associated with coronary
bypass surgery. It also frees the surgeon from having to perform
multiple anastomoses, as is necessary in the current process.
[0009] The present device provides a conduit for diverting blood
directly from a heart chamber, such as the left ventricle of the
heart, to the coronary artery distal to the blockage or stenosis,
thereby bypassing the blocked portion of the vessel. The conduit
comprises a tube adapted to be positioned in the heart wall and
having a section of blood vessel attached to the interior of the
conduit, to provide a passage for blood flow which is similar to
the body's own blood vessels.
[0010] The conduit device is delivered through the coronary artery
to a position distal the blockage or stenosis. At that position,
the coronary artery and the wall of the left ventricle, including
the myocardium, are pierced to provide an opening or channel
completely through from the coronary artery to the left ventricle
of the heart. The conduit is then positioned in the opening to
provide a permanent passage for blood to flow between the left
ventricle of the heart and the coronary artery, distal to the
blockage or stenosis.
[0011] The conduit is sized so that one open end is positioned
within the coronary artery, while the other open end is positioned
in the left ventricle. Prior to implantation of the conduit, a
section of vein or other blood vessel is obtained from the patient,
from another human donor, or from a nonhuman animal. The vein or
other blood vessel is sized so as to fit within the interior of the
conduit. The hollow lumen of the conduit with the blood vessel
graft inserted therein provides a passage for the flow of
blood.
[0012] If desired, the section of blood vessel inserted into the
conduit may include one or more naturally occurring one-way valves.
The valve prevents the backflow of blood from the myocardium into
the left ventricle. For example, a section of vein having a valve
therein can be used. Alternatively, the pulmonic valve or aortic
valve obtained from a nonhuman animal, such as a fetal pig or
piglet, can be used to provide a one-way passage for the flow of
blood through the conduit.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1A is a schematic, cross-sectional view of a human
heart, showing a conduit in the myocardium of the heart for forming
a bypass between the left ventricle and a coronary artery;
[0014] FIG. 1B is an enlarged view of the bypass conduit of FIG.
1A;
[0015] FIG. 2 is an exploded view of a vein graft incorporated into
a heart conduit in accordance with the preferred arrangement;
[0016] FIG. 3 is a close-up, cross-sectional view of a blockage or
stenosis in the coronary artery, illustrating the conduit of the
preferred arrangement positioned so as to bypass the blockage or
stenosis.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0017] As is well known, the coronary artery branches off the aorta
and is positioned along the external surface of the heart wall.
Oxygenated blood that has returned from the lungs to the heart then
flows from the heart to the aorta. Some blood in the aorta flows
into the coronary arteries, and the remainder of blood in the aorta
flows on to the rest of the body. The coronary arteries are the
primary blood supply to the heart muscle and are thus critical to
life. In some individuals, atherosclerotic plaque, aggregated
platelets, and/or thrombi build up within the coronary artery,
blocking the free flow of blood and causing complications ranging
from mild angina to heart attack and death. The presence of
coronary vasospasm, also known as "variant angina" or "Prinzmetal's
angina," compounds this problem in many patients.
[0018] As used herein, the term "heart chamber" primarily refers to
the interior, or lumenal, aspect of the left or right ventricle or
the left or right atrium. The term "conduit," "stent," and "tube"
herein refer to physical structures, preferably primarily
artificial, that can be positioned between two or more chambers or
vessels, to allow blood flow from one chamber or vessel to another.
A "shunt" is any natural or artificial passage between natural
channels, such as heart chambers or blood vessels. The conduit in
the preferred arrangement can be made of a variety of materials,
including various metals, such as nitinol, or plastics.
[0019] As used herein, the term "heart wall" comprises any one or
more of the following portions or layers of the mammalian heart:
the epicardium, myocardium, endocardium, pericardium, interatrial
septum, and interventricular septum.
[0020] The principles of the present invention are not limited to
left ventricular conduits; and include conduits for communicating
bodily fluids from any space within a patient to another space
within a patient, including any mammal. Furthermore, such fluid
communication through the conduits is not limited to any particular
direction of flow and can be antegrade or retrograde with respect
to the normal flow of fluid. Moreover, the conduits may communicate
between a bodily space and a vessel or from one vessel to another
vessel (such as an artery to a vein or vice versa). Moreover, the
conduits can reside in a single bodily space so as to communicate
fluids from one portion of the space to another. For example, the
conduits can be used to achieve a bypass within a single vessel,
such as communicating blood from a proximal portion of an occluded
coronary artery to a more distal portion of that same coronary
artery.
[0021] In addition, the conduits and related methods can preferably
traverse various intermediate destinations and are not limited to
any particular flow sequence. For example, in one preferred
embodiment of the present invention, the conduit communicates from
the left ventricle, through the myocardium, into the pericardial
space, and then into the coronary artery. However, other preferred
embodiments are disclosed, including direct transmyocardial
communication from a left ventricle, through the myocardium and
into the coronary artery. Thus, as emphasized above, the term
"transmyocardial" should not be narrowly construed in connection
with the preferred fluid communication conduits, and other
nonmyocardial and even noncardiac fluid communication are preferred
as well. With respect to the walls of the heart (and more
specifically the term "heart wall"), the preferred conduits and
related methods are capable of fluid communication through all such
walls including, without limitation, the pericardium, epicardium,
myocardium, endocardium, septum, etc.
[0022] The bypass which is achieved with certain preferred
embodiments and related methods is not limited to a complete bypass
of bodily fluid flow, but can also include a partial bypass which
advantageously supplements the normal bodily blood flow. Moreover,
the obstructions that are bypassed may be of a partial or complete
nature, and therefore the terminology "bypass" or "occlusion"
should not be construed to be limited to a complete bypass or a
complete occlusion but can include partial bypass and partial
occlusion as described.
[0023] The preferred conduits and related methods disclosed herein
can also provide complete passages or partial passages through
bodily tissues. In this regard, the conduits can comprise stents,
shunts, or the like, and therefore provide a passageway or opening
for bodily fluid such as blood. Moreover, the conduits are not
necessarily stented or lined with a device but can comprise mere
tunnels or openings formed in the tissues of the patient.
[0024] The conduits of the present invention preferably comprise
both integral or onepiece conduits as well as plural sections
joined together to form a continuous conduit. The present conduits
can be deployed in a variety of methods consistent with sound
medical practice including vascular or surgical deliveries,
including minimally invasive techniques. For example, various
preferred embodiments of delivery rods and associated methods are
disclosed. In one embodiment, the delivery rod is solid and
trocar-like. It may be rigid or semi-rigid and capable of
penetrating the tissues of the patient and thereby form the
conduit, in whole or in part, for purposes of fluid communication.
In other preferred embodiments, the delivery rods may be hollow so
as to form the conduits themselves (e.g., the conduits are
preferably self implanting or self inserting) or have a conduit
mounted thereon (e.g., the delivery rod is preferably withdrawn
leaving the conduit installed). Thus, the preferred conduit device
and method for installation is preferably determined by appropriate
patient indications in accordance with sound medical practices.
[0025] In order to restore the flow of oxygenated blood through the
coronary artery, the preferred arrangement provides for the
shunting of blood directly from the heart to a site in the coronary
artery which is distal the blockage or stenosis.
[0026] Although the specification herein will describe the conduit
primarily with reference to the left ventricle, the preferred
arrangement can be used with any of the four heart chambers, and
with any coronary artery, including the left main coronary artery,
the right coronary artery, the left anterior descending artery, the
left circumflex artery, the posterior descending artery, the obtuse
marginal branch or a diagonal branch.
[0027] A tunnel or opening is formed through the wall of the
coronary artery and the myocardium and into the left ventricle of
the heart which lies beneath, or deep to, the coronary artery. A
conduit is positioned in the opening to keep it open.
[0028] The conduit may be introduced into the myocardium in a
variety of ways, including by a catheter threaded through the
femoral artery into the aorta and thence into the left ventricle
and, if necessary, the left atrium; or by a catheter threaded
through the femoral vein into the inferior vena cava and thence
into the right atrium and right ventricle. Alternatively, the
conduit may be introduced through a surgical incision in chest wall
(thoracotomy) or sternum (sternotomy).
[0029] Further details regarding conduits and conduit delivery
systems are described in patent applications entitled, DESIGNS FOR
LEFT VENTRICULAR CONDUIT, U.S. application Ser. No. 09/369,048,
filed Aug. 4, 1999, VALVE DESIGNS FOR LEFT VENTRICULAR CONDUIT,
U.S. application Ser. No. 09/368,393, filed Aug. 4, 1999, LEFT
VENTRICULAR CONDUITS TO CORONARY ARTERIES AND METHODS FOR CORONARY
BYPASS, U.S. application Ser. No. 09/534,038, filed Mar. 24, 2000,
and BLOOD FLOW CONDUIT DELIVERY SYSTEM AND METHOD OF USE, U.S.
application Ser. No. 09/368,644, filed Aug. 4, 1999, and U.S. Pat.
Nos. 6,261,304, 5,429,144 and 5,662,124, the disclosures of which
are all hereby incorporated by reference in their entirety.
[0030] The opening through the heart wall (including endocardium,
myocardium, and epicardium) and coronary artery can be formed in a
variety of ways, including by knife or scalpel, electrocautery,
cryoablation, radiofrequency ablation, ultrasonic ablation, and the
like. Other methods will be apparent to those of ordinary skill in
the art.
[0031] The conduit is provided with a section of vein or other
blood vessel positioned within its interior lumen. The section of
vein or other blood vessel is obtained from the patient, from a
donor, or from an animal. Prior to implantation of the conduit. a
segment of blood vessel sized to fit with the lumen of the conduit
is inserted into the conduit. The conduit with the graft therein
provides a passage for the flow of blood which is similar to the
natural human blood vessels. The segment of vein or other blood
vessel harvested to fit within the conduit may include one or more
of the valves which naturally occur in the human body. These valves
act to prevent the backflow of blood. In the conduit, these
naturally occurring venous valves prevent the blood from flowing
back into the left ventricle of the heart from the coronary artery.
The segment of vein is preferably inserted into the conduit prior
to the conduit's deployment into the human body by any of various
surgical or catheter-guided techniques known to those of skill in
the art.
[0032] Referring now to FIGS. 1A and 1B, a coronary artery bypass
is accomplished by disposing a conduit 12 (FIG. 1B) in a heart wall
or myocardium MYO of a patient's heart PH (FIG. 1A). The conduit 12
preferably extends from the left ventricle LV of heart PH to a
clogged coronary artery CA at a point downstream of a blockage BL
to create a passageway 8 therethrough. Conduit 12 is preferably
made of a biocompatible material such as stainless steel or
nitinol, although other materials such as Ti, Ti alloys, Ni alloys,
Co alloys and biocompatible polymers may also be used. In one
embodiment, conduit 12 has a one way valve 6 to allow blood to flow
from the left ventricle LV to the coronary artery CA. Although the
conduit 12 may elastically deform under the contractive pressure of
the heart muscle during systole, the stent remains open to allow
blood to pass from the patient's left ventricle LV into the
coronary artery CA. During diastole, the blood pumped into coronary
artery through passageway 8 is blocked by one-way valve 6 from
returning to left ventricle LV.
[0033] As shown in FIG. 2, a preferred embodiment involves the use
of a vein graft 10 taken from the patient. Prior to preparing the
conduit 12 for placement in the patient, a section of vein 10 is
obtained from the patient (e., an autologous graft or autograft).
Of course, a blood vessel taken from another human donor (i.e., an
allogeneic graft or allograft) or nonhuman animal species (i.e., a
heterologous graft or xenograft) could also be used. The vein 10 is
preferably taken from the saphenous vein in the leg of the patient.
Alternatively, a donor vein could be used, or a fetal pig or piglet
can be obtained and dissected to remove a section of the pulmonary
artery having a pulmonic valve therein, or a section of the aorta
having an aortic valve therein, or a similar vessel having a
naturally occurring valve system. In other embodiments, the
endothelial lining of a vein and/or a valve may be grown from one
or more tissue cultures, utilizing cloning of donor cell lines or
other genetic engineering techniques (or "tissue engineering")
known to those of skill in the art. Thus, as used herein, "a
section of blood vessel" may include one or more of the following:
a surgically resected segment of a blood vessel, with or without
one or more valves; the endothelial lining of a blood vessel, taken
from an in vitro or in vivo specimen; and one or more venous
valves, taken from in vitro or in vivo specimens.
[0034] As noted above, the section of vein 10 or other blood vessel
harvested preferably contains one or more valves 14, which occur
naturally in the veins. The section of vein 10 may also not have a
valve. The vein section 10 is sized so as to be the same length as
the conduit 12. The vein section 10 is placed within the interior
lumen of the conduit 12 and attached to the inside of the conduit
12 by suturing or other attachment methods. The natural vein graft
10 is biocompatible and therefore reduces problems associated with
rejection of the conduit 12 and clotting around or in the conduit
12. In addition, the vein 10 provides a natural valve system 14
that is already used throughout the human body to prevent the
backflow of blood. In the case of a xenograft, treatment of the
graft with chemicals, such as glutaraldehyde, may be undertaken to
remove living cells, including antigenic materials, from the
connective tissue framework of the graft so as to reduce
thrombogenicity and antigenicity.
[0035] Referring now to FIG. 3, a self-expanding conduit 12 having
a section of vein 10 therein is introduced into the wall of the
myocardium MYO as follows. A conduit delivery catheter (not shown),
having the compressed conduit 12 mounted on its distal end, is
advanced over a puncture mechanism and into the wall of the
myocardium MYO at a site distal to the blockage or stenosis BL in
the coronary artery CA. When the conduit 12 is properly seated in
the myocardial wall MYO, its retaining sheath is withdrawn,
allowing the conduit 12 to expand and open a passageway, or
maintain patency of the passageway, from the left ventricle of the
heart LV to the coronary artery CA. This allows oxygenated blood to
flow directly from the left ventricle of the heart LV through the
conduit 12 and to the coronary artery CA, bypassing the section of
coronary artery CA that is blocked BL, as shown by the arrows in
FIG. 3.
[0036] The conduit 12 may include attachment mechanisms not limited
to hooks, barbs, large collars, and/or other methods to ensure that
a seal is created between the coronary artery CA and the wall of
the heart wall MYO, to prevent hemorrhaging and to prevent the
threat of or actual conduit migration. When positioning and
securing of the conduit 12 is completed, the remaining catheter
assembly is removed, leaving the conduit 12 with the vein graft
therein, in place in the body.
[0037] The present vascular conduit having a blood vessel graft
incorporated therein provides significant improvements in the
present treatment of blockages or stenoses in the coronary artery.
Although the invention has been described in its preferred
embodiments in connection with the particular figures, it is not
intended that this description should be limited in any way by the
foregoing.
* * * * *