U.S. patent application number 09/783720 was filed with the patent office on 2002-02-14 for bifurcated vascular graft and method and apparatus for deploying same.
Invention is credited to Douglas, Myles S..
Application Number | 20020019664 09/783720 |
Document ID | / |
Family ID | 25183805 |
Filed Date | 2002-02-14 |
United States Patent
Application |
20020019664 |
Kind Code |
A1 |
Douglas, Myles S. |
February 14, 2002 |
Bifurcated vascular graft and method and apparatus for deploying
same
Abstract
A structurally supported bifurcated vascular graft is described
having a hollow cylindrical body graft with a top end and bottom
end and two hollow cylindrical limb grafts which are attached to
the hollow cylindrical body graft near the top end of the body
graft. One or more structural supports or stents are attached to
either the interior or exterior of the body graft and limb grafts.
Further, an apparatus and method for delivering a one-piece
bifurcated vascular graft is also described which includes first
and second hollow limb tubes for containing the limbs of a
bifurcated graft, a third hollow body tube for containing the body
of a graft, and a hollow delivery tube capable of encompassing the
limb tubes and graft body tube.
Inventors: |
Douglas, Myles S.; (Phoenix,
AZ) |
Correspondence
Address: |
KNOBBE MARTENS OLSON & BEAR LLP
620 NEWPORT CENTER DRIVE
SIXTEENTH FLOOR
NEWPORT BEACH
CA
92660
US
|
Family ID: |
25183805 |
Appl. No.: |
09/783720 |
Filed: |
February 14, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09783720 |
Feb 14, 2001 |
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09505038 |
Feb 16, 2000 |
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6210422 |
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09505038 |
Feb 16, 2000 |
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08802478 |
Feb 20, 1997 |
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6090128 |
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Current U.S.
Class: |
623/1.35 |
Current CPC
Class: |
A61F 2/95 20130101; A61F
2002/065 20130101; A61F 2/954 20130101; A61F 2002/075 20130101;
A61F 2002/072 20130101; A61F 2/89 20130101; A61F 2/07 20130101;
A61F 2230/0067 20130101 |
Class at
Publication: |
623/1.35 |
International
Class: |
A61F 002/06 |
Claims
I claim:
1. A bifurcated vascular graft comprising: a hollow tubular body
member having first and second open ends; a first hollow tubular
limb member having first and second open ends; and a second hollow
tubular limb member having first and second open ends wherein the
first open end of each of said first and second hollow tubular limb
members are connected to the hollow tubular body member near the
first open end of said hollow tubular body member such that a
length of said limb members are circumferentially contained within
said hollow tubular body member.
2. The bifurcated vascular graft of claim 1 wherein said first and
second hollow tubular limb members have approximately equal
diameters, said diameters being smaller than a diameter of said
hollow tubular body member.
3. The bifurcated vascular graft of claim 1 wherein said first and
second hollow tubular members extend beyond the second end of the
hollow tubular body member.
4. The bifurcated vascular graft of claim 1 further comprising at
least one of a first stent and first structural support located
adjacent to the first end of said hollow tubular body member.
5. The bifurcated vascular graft of claim 4 wherein said at least
one of a first stent and first structural support is positioned
about an interior portion of said hollow tubular body member.
6. The bifurcated vascular graft of claim 4 further comprising at
least one of a second stent and second structural support located
adjacent to the second end of said first hollow tubular limb
member.
7. The bifurcated vascular graft of claim 6 wherein said at least
one of a second stent and second structural support is positioned
about an exterior of said first hollow tubular limb member.
8. The bifurcated vascular graft of claim 6 further comprising at
least one of a third stent and a third structural support located
adjacent to the second end of said second hollow tubular limb
member.
9. The bifurcated vascular graft of claim 8 wherein said at least
one of a third stent and third structural support is positioned
about an exterior of said first hollow tubular limb member.
10. The bifurcated vascular graft of claim 9 wherein a portion of
the second ends of said first and second hollow tubular limb
members are folded back over said at least one of a second stent
and second structural support and at least one of a third stent and
third structural support, respectively, such that the second ends
of said first and second hollow tubular limb members form
cuffs.
11. The bifurcated vascular graft of claim 1 wherein said first and
second hollow tubular limb members are attached to one another
along a portion of a circumference of their first open ends.
12. The bifurcated vascular graft of claim 11 wherein at least a
portion of the circumference of the first ends of each of said
first and second hollow tubular limb members is attached to a
portion of a circumference of the first end of said hollow tubular
body member.
13. The bifurcated vascular graft of claim 11 wherein the
attachment between the first open ends of the first and second
hollow tubular limb members is seamless.
14. The bifurcated vascular graft of claim 11 further comprising a
reinforcement suture positioned under the attachment area of the
first ends of said first and second hollow tubular limb
members.
15. The bifurcated vascular graft of claim 11 further comprising:
at least one of a first stent and a first structural support
located adjacent the first open end of said first hollow tubular
body member; at least one of a second stent and a second structural
support located adjacent the second open end of said first hollow
tubular limb member; and at least one of a third stent and a third
structural support located adjacent the second open end of said
second hollow tubular limb member.
16. The bifurcated vascular graft of claim 15 wherein said at least
one of a first stent and first structural support is positioned
about an interior of said hollow tubular body member, said at least
one of a second stent and second structural support is positioned
about an exterior of said first hollow tubular limb member, and
said at least one of a third stent and third structural support is
positioned about an exterior of said second hollow tubular limb
member.
17. The bifurcated vascular graft of claim 16 wherein a portion of
the second ends of said first and second hollow tubular limb
members are folded back over said at least one of a second stent
and second structural support and at least one of a third stent and
third structural support, respectively, such that the second ends
of said first and second hollow tubular limb members form
cuffs.
18. A method for making a bifurcated vascular graft comprising the
steps of: a) cutting about a middle circumference of a thin hollow
tube until approximately 3/4 of the circumference is cut; b)
folding said thin hollow tube away from an uncut portion at the cut
of the thin hollow tube to form two hollow tubular limb members
having equal diameters which are attached to one another along the
fold; c) positioning said hollow tubular limb members within a
hollow tubular body member having a diameter at least twice the
diameter of said hollow tubular limb members; and d) attaching the
cut ends of the hollow tubular limb members to an end of said
hollow tubular body member such that a length of said limb members
are circumferentially contained within said hollow tubular body
member.
19. The method of claim 18 further comprising the step of sewing a
support suture underneath the uncut fold between the two hollow
tubular limb members.
20. The method of claim 18 further comprising the steps of: a)
positioning a first structural support adjacent the end of the
hollow tubular member containing the attachment of the cut ends of
the two hollow tubular members wherein the first structural support
is located about an interior of the hollow tubular member; and b)
positioning second and third structural supports about an exterior
of the two hollow tubular limb members, respectively, at ends of
the two hollow tubular limb members that are opposite the fold.
21. The method of claim 19 further comprising the step of folding
the opposite ends of the hollow tubular limb members back over the
first and second structural supports, respectively, to form
cuffs.
22. A deployment apparatus for deploying a bifurcated graft having
a main graft body which bifurcates into first and second limbs
comprising: a first limb tube for loading the first limb; a second
limb tube for loading the second limb wherein the first, and second
loaded limb tubes are positioned parallel to one another; a graft
body tube for loading the main graft body wherein the graft body
tube is positioned adjacent to parallel ends of the first and
second limb tubes; and an outermost tube for loading the first and
second limb tubes and the graft body tube such that all of said
tubes are contained within the outermost tube.
23. The deployment apparatus of claim 22 further comprising a metal
tube for containing a guide wire wherein the metal tube is
insertable throughout an entire length of the apparatus.
24. The deployment apparatus of claim 22 further comprising a first
homeostatic valve connected to said first limb tube.
25. The apparatus of claim 24 further comprising a second
homeostatic valve connected to said outermost tube.
26. The apparatus of claim 22 further comprising a tapered tip
capable of fitting onto an open end of said graft body tube.
27. The apparatus of claim 22 wherein said second limb tube
comprises a first open end, a second closed tapered end and a guide
wire attached to said tapered end.
28. The apparatus of claim 27 wherein said second limb tube is
shorter in length than said first limb tube.
29. The apparatus of claim 22 wherein said first and second limb
tubes have approximately equal diameters.
30. A deployment apparatus for deploying a bifurcated graft having
a main graft body which bifurcates into first and second limbs
comprising: a first limb tube for loading the first limb; a second
limb tube for loading the second limb wherein the first and second
loaded limb tubes are positioned parallel to one another; a graft
body tube for loading the main graft body wherein the first and
second limb tubes are contained within at least a portion of said
graft body tube; and an outermost tube for loading the first and
second limb tubes and the graft body tube such that all of said
tubes are contained within the outermost tube.
31. The deployment apparatus of claim 30 further comprising a metal
tube for containing a guide wire wherein the metal tube is
insertable throughout an entire length of the apparatus.
32. The deployment apparatus of claim 30 further comprising a first
homeo static valve connected to said first limb tube.
33. The apparatus of claim 32 further comprising a second
homeostatic valve connected to said outermost tube.
34. The apparatus of claim 30 further comprising a tapered tip
capable of fitting onto an open end of said graft body tube.
35. The apparatus of claim 30 wherein said second limb tube
comprises a first open end, a second closed tapered end and a guide
wire attached to said tapered end.
36. The apparatus of claim 35 wherein said second limb tube is
shorter in length than said first limb tube.
37. The apparatus of claim 30 wherein said first and second limb
tubes have approximately equal diameters.
38. A method for intraluminal delivery of a bifurcated vascular
graft, having a main graft body which bifurcates into first and
second limbs, within a patient comprising the steps of a) loading
the first limb of the graft into a first tube, the second limb of
the graft into a second tube, the main graft body into a third
tube; b) inserting the first, second and third tubes endolurninally
within the patient; b) positioning the first, second and third
tubes within the patient; c) deploying the first limb by removing
the first tube; d) deploying the second limb by removing the second
tube; and e) deploying the third limb by removing the third
tube.
39. The method of claim 38 further comprising the steps of: a)
inserting the first, second and third tubes into a main tube; and
b) removing the main tube to uncover the first, second and third
tubes.
Description
FIELD OF THE INVENTION
[0001] The present invention generally relates to a bifurcated
graft and an apparatus and method for delivering the same within
the body of a patient using a minimally invasive procedure. More
particularly, the present invention includes a bifurcated vascular
graft having two hollow cylindrical limb grafts of an equal first
diameter attached to one another along a portion of their
circumferences at their first ends and a third hollow cylindrical
body graft of a larger diameter circumferentially positioned over
the first two hollow cylindrical limb grafts such that the
remaining unconnected end circumferences of the first two hollow
cylindrical limb grafts are connected about an end circumference of
the third hollow cylindrical body graft thereby bisecting the
diameter of the third hollow cylindrical body graft in half.
[0002] The present invention also includes an apparatus and method
for delivering the bifurcated vascular graft of the present
invention which includes first and second hollow limb tubes of
approximately equal diameter and varying lengths for containing the
two hollow cylindrical limb grafts, a third hollow body tube having
a larger diameter than the first and second hollow limb tubes for
containing the hollow cylindrical body graft, a metal tube for
containing a guide wire, and a hollow delivery tube which is
capable of encompassing the first and second hollow limb tubes, the
hollow body tube, and the metal tube.
BACKGROUND OF THE INVENTION
[0003] Endoluminal repair or exclusion of aortic aneurysms has been
performed for the past several years. The goal of endoluminal
aortic aneurysm exclusion has been to correct this life threatening
disease in a minimally invasive manner in order to effectuate a
patient's quick and complete recovery. Various vascular grafts
exist in the prior art which have been used to exclude aortic
aneurysms. These prior art grafts have been met with varying
degrees of success.
[0004] Initially, straight tube grafts were used in the abdominal
aorta to exclude the aneurysmal sac from the blood stream thereby
resulting in the weakened aortic wall being protected by the graft
material. These straight tube grafts were at first unsupported
meaning that they employed stents at their proximal and distal ends
to anchor the proximal and distal ends of the graft to the healthy
portions of the aorta thereby leaving a midsection of the graft or
prosthesis that did not have any internal or stented support.
Although this type of graft at first appeared to correct the aortic
aneurysm, it met with many failures. The unsupported nature of its
midsection allowed the graft to migrate distally as well as exhibit
significant proximal leakage due to the enlargement of the aorta
without adaptation of the graft, such as enlargement of the graft,
to accommodate the change in diameter of the aorta.
[0005] Later, technical improvements in stent design led to
"self-expanding" stents. In addition, latter improvements produced
"Nitinol" stents which had a "memory" that was capable of expanding
to a pre-determined size. Coincidentally, graft designers began to
develop bifurcated grafts having limbs which extended into the
iliac arteries. The development of bifurcated grafts allowed for
the treatment of more complex aneurysms.
[0006] With the advent of bifurcated grafts, the need for at least
a one centimeter neck from the distal aspect of the aneurysmal sac
to the iliac bifurcation in order to treat the aneurysm with an
endoluminal graft was no longer needed. However, proximal necks of
at least 0.5 to 1 centimeter distance from the renal arteries to
the most proximal aspect of the aneurysm are still required.
[0007] Many bifurcated grafts are of a two piece design. These two
piece designs require the insertion of a contralateral limb through
a separate access site. These types of grafts are complex to deploy
and have the potential for leakage at the connection site of the
two limbs of the graft. One piece bifurcated grafts have also been
designed. However, there deployment is still somewhat complicated
and has torsion tendencies.
[0008] One piece bifurcated gafts are well known in the art. For
example, U.S. Pat. No. 2,845,959 discloses a one piece seamless
woven textile bifurcated tube for use as an artificial artery.
Yarns of varying materials can be used to weave the bifurcated
graft including nylon and plastic yarns. U.S. Pat. Nos. 3,096,560
and 3,029,819 issued to Liebig and Starks, respectively, disclose
woven one piece bifurcated grafts which are constructed by
performing specific types of winding and weaving about a smooth
bifurcated mandrel.
[0009] U.S. Pat. No. 4,497,074 describes a one piece bifurcated
graft which is made from a preformed support in the shape of the
bifurcated graft (i.e. mould). In a first stage, a gel enabling a
surface state close to that of the liquid-air interface to be
obtained at the gel-air interface is deposited by dipping or
coating the preform with a sol which is allowed to cool. A
hardenable flexible material such as a silicone elastomer by
dipping or spraying the material on the mould in a second stage.
Finally, after hardening of the material, the prosthesis is removed
from the mould. In U.S. Pat. No. 4,816,028 issued to Kapadia et
al., there is shown a one piece woven bifurcated vascular graft
having a plurality of warp threads running in the axial direction
and a plurality of weft threads running in the transverse
direction. Further, U.S. Pat. No. 5,108,424 issued to Hoffinan, Jr.
et al. discloses a one piece bifurcated collagen-impregnated dacron
graft. The bifurcated graft includes a porous synthetic vascular
graft substrate formed by knitting or weaving with at least three
applications of dispersed collagen fibrils.
[0010] The Herweck et al. patent, U.S. Pat. No. 5,197,976,
discloses a continuous one piece bifurcated graft having plural
longitudinally parallel tube structures which are attached to one
another over at least a portion of their longitudinal exteriors.
The tube structures can be manually separated to form a branched
tubular structure. The prosthesis is manufactures by paste forming
and stretching and/or expanding highly crystalline unsintered
polytetrafluoroethylene (PTFE). Paste forming includes mixing the
PTFE resin with a lubricant, such as mineral spirits, and then
forming the resin by extrusion into shaped articles.
[0011] Although all of the above described one piece bifurcated
grafts have eliminated the problems of leakage and graft failure at
the suture or juncture site associated with two piece bifurcated
grafts which join together two separate grafts to form the
bifurcated graft, problems still exist with these one piece
bifurcated grafts. For example, the previously described one piece
bifurcated grafts do not include an integral support structure to
prevent the deformation, twisting or collapse of the graft limbs.
Further, the same problems with graft migration that existed with
straight tube grafts still exist with the one piece bifurcated
grafts. Accordingly, there is a need for a stable and durable
bifurcated vascular graft which is structured to prevent the
migration of the graft and the deformation and obstruction of the
blood flow through the limbs of the bifurcated graft.
[0012] Endoluminal implantation is a common technique for
implanting vascular grafts. Typically, this procedure involves
percutaneously inserting a vascular graft or prosthesis by using a
delivery catheter. This process eliminates the need for major
surgical intervention thereby decreasing the risks associated with
vascular and arterial surgery. Various catheter delivery systems
for prosthetic devices are described in the prior art.
[0013] For example, bifurcated vascular grafts have been created by
combining grafts with stents on delivery systems in order to secure
the graft ends to the blood vessel thereby stabilizing the
bifurcated graft. In U.S. Pat. No. 5,360,443 issued to Barone et
al. A method for repairing an abdominal aortic aneurysm is
described. The method comprises the steps of 1) connecting an
expandable and deformable tubular member, such as a stent, to each
of the tubular passageways of a bifurcated graft, 2) disposing the
bifurcated graft and deformable tubular members within the aortic
and iliac arteries, and 3) expanding and deforming each deformable
tubular member with a catheter to secure each tubular passageway of
the bifurcated graft within the appropriate artery. This reference
only discloses a catheter delivery method for deploying the aortic
portion of the bifurcated graft. The same catheter is supposedly
used to also expand and secure the associated stents within the
iliac arteries. The Palmaz et al. patent, U.S. Pat. No. 5,316,023,
describes a method and apparatus for repairing an abdominal aortic
aneurysm in an aorta having two iliac arteries. This method
includes the steps of connecting a first tubular graft to a first
deformable and expandable tubular member, connecting a second
tubular graft to a second deformable and expandable tubular member,
disposing the first tubular graft and first tubular member upon a
first catheter having an inflatable portion, disposing the second
tubular graft and second tubular member upon a second catheter
having an inflatable portion, intraliminal delivering the first and
second tubular grafts, tubular members and catheters to the aorta
and disposing at least a portion of each tubular graft within the
abdominal aortic aneurysm, and expanding the tubular members with
the inflatable catheters to secure them and at least a portion of
their associated tubular grafts within the aorta. This patent
reference employs two separate unconnected straight grafts which
are employed within an aorta to form a bifurcated graft.
[0014] Further, U.S. Pat. No. 4,617,932 issued to Komberg discloses
a device for inserting a graft into an artery comprising a
plurality of nested tubes each having an upper and lower end. A
first outer tube has a means for guiding and positioning an arm
means at its upper end. The arm means is movably attached to the
upper end of another tube located inside of the first tube and
extending above the first outer tube. The lower ends of the tubes
are adaptable for fastening means and the inside tube extends below
the end of the first outer tube. Delivery and placement of a
bifurcated graft is illustrated. U.S. Pat. No. 5,522,883 issued to
Slater et al. describes an endoprosthesis stent/graft deployment
system which includes a tubular delivery catheter, a radially
expandable prosthesis positioned over the catheter, a removable
endoprosthesis support assembly located adjacent the catheter
opening and having an arm extending through the catheter which
keeps the endoprosthesis in a compressed state, and a release
mechanism insertable through the catheter for removing the support
assembly.
[0015] U.S. Pat. No. 5,104,399 issued to Lazarus also describes an
artificial graft and delivery method. The delivery system includes
a capsule for transporting the graft through the blood vessel, a
tube connected to the vessel which extends exterior to the vessel
for manipulation by a user, and a balloon catheter positioned
within the tube. Finally, U.S. Pat. No. 5,489,295 issued to Piplani
et al. discloses a bifurcated graft and a method and apparatus for
deploying the bifurcated graft. The Piplani et al. graft includes a
main tubular body, first and second tubular legs joined to the main
tubular body in a bifurcation, a first expandable attachment means
for anchoring the main body located adjacent the opening for the
first body, and a second expandable attachment means located
adjacent the opening of the first tubular leg for anchoring the
first tubular leg. The graft is intraluminally implanted using a
catheter that is inserted into the aortic bifurcation through a
first iliac artery so that the first attachment means adjacent the
opening of the main body can be anchored in the aorta and the
second attachment means adjacent the opening of the first tubular
leg can be anchored in the first iliac artery. The second tubular
leg is deployed into the second iliac artery by using a pull line
attached to the second tubular leg. The Piplani et al. patent also
discloses a deployment device consisting of a capsule catheter, a
balloon catheter, and a separate expandable spring attachment
means.
[0016] The previously described deployment methods, systems and
devices do not allow for a bifurcated graft which is fully
supported with self expandable stents to be delivered and implanted
within an arterial bifurcation. A use of any of the previously
described deployment devices or systems to implant the structural
supported bifurcated graft of the present invention would result in
failure due to the inability of those devices and systems to
deliver and anchor the second supported limb within the second
iliac artery. The previously described methods and systems simply
do not allow for the delivery and implantation of a bifurcated
vascular graft whose three open ends are supported by stents.
Accordingly, not only is there a need for a structurally supported
stable and durable bifurcated graft which is not susceptible to
migration and leaking, but there is also a need for a delivery
apparatus and method for deploying and implanting such a bifurcated
graft.
SUMMARY OF THE INVENTION
[0017] It is a principal object of the present invention to provide
a bifurcated vascular graft and a method and apparatus for
deploying the bifurcated vascular graft.
[0018] It is another object of the present invention to provide a
bifurcated vascular graft having partial structurally supported
limbs which will not deform, twist, or collapse thereby preventing
the obstruction of blood flow through the limbs of the bifurcated
vascular graft.
[0019] It is yet another object of the present invention to provide
a bifurcated vascular graft having a structurally supported main
graft body which lends support to an unsupported portion of the
limbs of the bifurcated vascular graft in order to prevent
migration of the bifurcated vascular graft.
[0020] It is still another object of the present invention to
provide a structurally supported, physically stable bifurcated
vascular graft which will occlude small blood vessels from bleeding
into the bifurcated vascular graft area.
[0021] It is still another object of the present invention to
provide a bifurcated vascular graft having separate limb channels
thereby allowing for partial deployment of the bifurcated graft.
The advantage of this design can be seen when one limb of the graft
fails to deploy due to anatomic or structural problems. In that
event, the successfully deployed graft limb will be capable of
routing blood to the occluded limb by way of a femoral-femoral
bypass. Most of the present bifurcated graft designs are not
recoverable in this way and their failure to deploy usually forces
a conversion to classic surgery.
[0022] It is yet another object of the present invention to provide
a method and apparatus for deploying any one-piece bifurcated
graft, including the bifurcated vascular graft of the present
invention, within the body of a patient.
[0023] Still another object of the present invention is to provide
a method and apparatus for intraluminally deploying a
one-piece.bifurcated graft, including the bifurcated vascular graft
of the present invention, within a patient's body which is simple
and efficient.
[0024] Yet another object of the present invention is to provide a
method and apparatus for repairing an abdominal aortic aneurysm
which is noninvasive and which does not require suturing of the
graft to the aortic wall or iliac arteries.
[0025] In brief, the bifurcated vascular graft of the present
invention includes:
[0026] a hollow tubular body member having first and second open
ends;
[0027] a first hollow tubular limb member having first and second
open ends; and
[0028] a second hollow tubular limb member having first and second
open ends wherein the first open end of each of the first and
second hollow tubular limb members is connected to the hollow
tubular body member near the first open end of the hollow tubular
body member such that a length of the limb members are
circumferentially contained within the hollow tubular body
member.
[0029] The bifurcated vascular graft may include stents or similar
support structures that are placed adjacent to the three openings
contained in the bifurcated vascular graft. One stent may be
positioned such that it encompasses the entire interior surface of
the hollow tubular body member while two additional stents may be
positioned about the exterior surface near the second ends of the
first and second hollow tubular limb members, respectively. Cuffs
may also be formed at the ends of these limb members by folding the
second ends of the grafts back over the stents.
[0030] A method for making the bifurcated vascular graft of the
present invention includes the steps of:
[0031] a) cutting about a middle circumference of a thin hollow
tube until approximately 3/4 of the circumference is cut;
[0032] b) folding the thin hollow tube at the cut away from the
uncut portion to form two hollow tubular limb members having equal
diameters which are attached to one another along the fold;
[0033] c) positioning the hollow tubular limb members within a
hollow tubular body member having a diameter at least twice the
diameter of the hollow tubular limb members; and
[0034] d) attaching the cut ends of the hollow tubular limb members
to an end of the hollow tubular body member such that a length of
the limb members are circumferentially contained within the hollow
tubular body member.
[0035] The method may also include the steps of positioning a first
structural support adjacent the end of the hollow tubular member
containing the attachment of the cut ends of the two hollow tubular
members wherein the first structural support is located about an
interior of the hollow tubular member, and positioning second and
third structural supports about an exterior of the two hollow
tubular limb members, respectively, at ends of the two hollow
tubular limb members that are opposite the fold.
[0036] In another aspect of the present invention, the preferred
apparatus for deploying a bifurcated vascular graft within the body
of a patient includes:
[0037] a first limb tube for loading the first limb;
[0038] a second limb tube for loading the second limb wherein the
first and second loaded limb tubes are positioned parallel to one
another;
[0039] a graft body tube for loading the main graft body wherein
the graft body tube is positioned adjacent to parallel ends of the
first and second limb tubes; and
[0040] an outermost tube for loading the first and second limb
tubes and the graft body tube such that all of said tubes are
contained within the outermost tube.
[0041] Another embodiment of the deployment apparatus includes
first and second limb tube members which can both be inserted into
the graft body tube at the same time. The deployment apparatus may
also include a metal tube and guide wire which are insertable
throughout an entire length of the apparatus The first and second
limb tubes have approximately equal diameters and the second limb
tube is preferably shorter than the first limb tube.
[0042] Finally, the method of the present invention for
intraluminally delivering a bifurcated vascular graft having a main
graft body which bifurcates into first and second limbs within a
patient's body includes the steps of a) loading the first and
second limbs and the main graft body into separate tubes, b)
inserting the tubes endoluminally within the patient, c)
positioning the tubes within the patient, and d) deploying the
limbs and the main body graft one at a time by removing their
respective tubes. One example in which this simple and noninvasive
method may be used is in the repair of an abdominal aortic
aneurysm.
[0043] Additional objects, features and advantages of the varying
aspects of the present invention will become more apparent from the
following description in which the preferred embodiments of the
present invention are set out in detail in conjunction with the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0044] In the drawings, which illustrate the best mode presently
contemplated for carrying out the invention,
[0045] FIG. 1 is an exploded perspective view of the deployment
apparatus of the present invention.
[0046] FIG. 2 is a perspective view of the structurally supported
bifurcated vascular graft of the present invention with structural
stent supports located on the interior of the graft shown in
phantom. Portions of the hollow tubular limb members of the
bifurcated vascular graft are also shown in phantom.
[0047] FIG. 3 is a right end view of the structurally supported
bifurcated vascular graft of the present invention which is taken
from the proximal end of the bifurcated vascular graft which
includes the main tubular body of the graft.
[0048] FIG. 4 is a cross-sectional view taken along line 4-4 of
FIG. 3.
[0049] FIG. 5 is a partial cross-sectional view of the deployment
apparatus of the present invention with the structurally supported
bifurcated vascular graft of the present invention shown loaded
within the deployment apparatus of the present invention prior to
deployment of the structurally supported bifurcated vascular
graft.
[0050] FIG. 6A is a perspective view of a second hollow limb tube
of the deployment apparatus of the present invention which holds
the second hollow tubular limb member of the bifurcated vascular
graft of the present invention during positioning, and prior to
deployment, of the bifurcated vascular graft of the present
invention.
[0051] FIG. 6B is a partial perspective view of a bifurcated blood
vessel with the blood vessel shown cut away to illustrate the
placement and positioning of the deployment apparatus of the
present invention which contains the structurally supported
bifurcated vascular graft of the present invention. Portions of the
outermost tube of the deployment apparatus are also shown cut away
to illustrate the position of the first and second limb tubes and
graft body tube which comprise the deployment apparatus. A portion
of the second limb tube is shown in phantom.
[0052] FIGS. 7A-7F are diagrams showing the method and apparatus of
the present invention used for deploying the structurally supported
bifurcated vascular graft of the present invention.
[0053] FIG. 7G is a partial perspective view of a bifurcated blood
vessel shown cut away to illustrate the structurally supported
bifurcated vascular graft of the present invention deployed and
anchored in place within the bifurcated blood vessel.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0054] An exploded perspective view of the deployment apparatus 20
of the present invention is shown in FIG. 1. The deployment
apparatus 20 includes a graft body tube 21 of variable length and
diameter having a tapered tip 22, a first limb tube 23 of variable
length and diameter which connects to a hemostatic valve 24, a
second limb tube 25 of variable length and diameter having a
tapered tip 26 and a guide wire 27 coming from the tapered tip, an
outermost tube 28 of variable length and diameter which is large
enough to contain the graft body tube 21 and the first and second
limb tubes 23 and 25 at the same time and a homeostatic valve 31
connected to the outermost tube 28, and a small metal guide tube 29
of variable length and diameter which is large enough to allow a
guide wire to pass therethrough. The metal guide tube 29 is
attached to the graft body tube 21 within the graft body tube 21
near its tapered end 22 when the device is fully loaded and ready
to deploy. A luer lock 12 is shown connected to the metal guide
wire 29 and a three-way stopcock for adding and removing fluid is
shown connected to the hemostatic valve 24 for the first limb tube
23. It should be noted that the deployment apparatus 20 of the
present invention may be used to deploy any one-piece bifurcated
graft, not just the bifurcated vascular graft 30 of the present
invention.
[0055] FIG. 2 shows a perspective view of the bifurcated vascular
graft 30 of the present invention. The bifircated vascular graft 30
comprises a hollow tubular body member 32, a first hollow tubular
limb member 34, and a second hollow tubular limb member 36. The
hollow tubular body member 32 has a first open end 38 and a second
open end 40. A first stent 42 is positioned about the interior of
the hollow tubular body member 32 to support the hollow tubular
graft body member 32. The first stent 42, or any other suitable
biocompatible structural support, preferably encompasses the entire
interior surface area of the hollow tubular body member 32 in order
to provide the necessary structural support. Further, the hollow
tubular body member 32 may be completely supported by attaching
several stents along the entire length of the hollow tubular body
member 32.
[0056] The first and second hollow tubular limb members 34 and 36
have approximately equal diameters, each of which is less than the
diameter of the hollow tubular body member 32. The first hollow
tubular limb member 34 comprises a first open end (not shown) and a
second open end 44. Similarly, the second hollow tubular limb
member 36 comprises a first open end (not shown) and a second open
end 46. Second and third stents 48 and 50, respectively, are
positioned adjacent the second ends 44 and 46 of the first and
second hollow limb members 34 and 36 such that they each cover an
exterior portion of their respective limb members 34 and 36. The
second and third stents 48 and 50 only encompass that portion of
their respective limb members 34 and 36 which extend from the
second end 40 of the hollow tubular body member 32. Alternatively,
the second and third stents 48 and 50 may encompass the entire
first and second hollow tubular limb members 34 and 36 by extending
along their entire lengths. Further, as previously explained with
reference to the first stent 42, the second and third stents 48 and
50 may each comprise a plurality of stents or structural supports.
Also, these stents may support the first and second hollow tubular
limb members 34 and 36 either externally or internally.
[0057] The first and second hollow tubular limb members 34 and 36
are circumferentially contained within the hollow tubular body
member 32 such that a portion of the hollow tubular limb members 34
and 36 transverse the length of the hollow tubular body member 32.
As, previously explained, the support structures used to provide
external structural support to those portions of the hollow tubular
limbs 34 and 36 which extend beyond the second end 40 of the hollow
tubular body member 32 may comprise one or more self expanding
stents of varying lengths or any other suitable biocompatible
structural support that will self expand to a surrounding vessel
diameter. The second and third stents 48 and 50 are joined and
anchored to the first stent 42 to form joints 49 and 51. This
configuration prevents twisting and/or misalignment of the limbs 34
and 36 of the graft 30.
[0058] When loading the bifurcated vascular graft 30 onto the
deployment apparatus 20 of the present invention, the first hollow
tubular limb member 34 is loaded into the first limb tube 23, the
second hollow tubular limb member 36 is loaded into the second limb
tube 25, and the hollow tubular body member 32 is loaded into the
graft body tube 21. In a preferred embodiment, the loaded first and
second limb tubes 23 and 25 may be dimensioned such that they will
lie end to end with the loaded graft body tube 21. Alternatively,
the loaded first and second limb tubes 23 and 25 may be of a small
enough diameter such that they can be inserted into the interior of
the graft body tube 21 so that they can contain the entire length
of the respective first and second hollow tubular limb members 34
and 36 within the graft body tube 21. The loaded graft body tube 21
and the loaded first and second limb tubes 23 and 25 are then all
loaded into the outermost tube 28 which is connected to a
homeostatic valve 31. The metal tube 29 containing a guide wire
(not shown), separate and distinct from the guide wire 26 connected
to the second limb tube 25, can be inserted through the entire
loaded apparatus.
[0059] Turning now to FIG. 3., a right end view of the structurally
supported bifurcated vascular graft 30 of the present invention is
shown with the right end view taken from the proximal end of the
bifurcated vascular graft. As can be seen from FIG. 3, the first
and second hollow tubular limb members 34 and 36 are connected to
one another along a diameter of the hollow tubular body member 32
which divides the lumen of the hollow tubular body member 32 in
half. The first and second hollow tubular limb members 34 and 36
include first and second lumens 52 and 54, respectively, which are
approximately equal to one another area and which fit inside of the
lumen of the hollow tubular body member 32. The first open ends 56
and 58 of the hollow tubular limb members 34 and 36, respectively,
can be seen from this right end view of the bifurcated vascular
graft 30. Those portions of the circumference of the first open
ends 56 and 58 of the first and second hollow tubular limbs 34 and
36 which are not attached to one another are connected to the
circumference of the first open end 38 of the of the hollow tubular
body member 32. The first stent 42 is located about the interior
surface area of the hollow tubular body member 32 and is thereby
contained between the interior of the hollow tubular body member 32
and the exteriors of the first and second hollow tubular limbs 34
and 36.
[0060] That portion of the circumference of the first ends 56 and
58 of the first and second hollow tubular limbs 34 and 36 which are
attached to one another may be supported by a cross support stitch
or support suture 60 which is positioned underneath the attached
area and within the interior of the hollow tubular body member 32.
Another stitch or suture 57 is placed across the diameter of the
second end 40 of the hollow tubular body member 32 such that the
ends 59 and 61 of the suture are left to trail from the second end
40 of the body member 32 in order to aid in the deployment of the
bifurcated vascular graft 30.
[0061] A cross-sectional view of the bifurcated vascular graft 30
of the present invention taken along line 44 of FIG. 2 is shown in
FIG. 3. The first ends 56 and 58 of the first and second hollow
tubular limbs 34 and 36 are attached to the first end 38 of the
hollow tubular body member 32 such that the first and second hollow
tubular limbs 34 and 36 are partially contained within the lumen of
the hollow tubular body member 32. The first stent 42 (or
structural support) is positioned about the interior surface of the
lumen of the hollow tubular body member 32 and is thereby contained
between the interior surface of the hollow tubular body member 32
and the exterior surfaces 62 and 64 of the first and second hollow
tubular limb members 34 and 36, respectively. The second and third
stents 48 and 50 (or structural supports) are positioned adjacent
the second ends 44 and 46 of the first and second hollow tubular
limb members 34 and 36, respectively, such that they encompass a
portion of the exterior surfaces 62 and 64 of the first and second
hollow tubular limb members 34 and 36, respectively. Also, as
previously described, the first and second hollow tubular limb
members 34 and 36 may be structurally supported with stents along
their entire length.
[0062] FIG. 5 shows a partial cross-section of the deployment
apparatus 20 of the present invention with the bifurcated vascular
graft 30 of the present invention loaded within the deployment
apparatus 20 prior to deployment of the graft 30. The first hollow
tubular limb member 34 of the bifurcated vascular graft 30 is shown
loaded into the first limb tube 23 and the second hollow tubular
limb member 36 of the bifurcated vascular graft 30 is shown loaded
into the second limb tube 25. The hollow tubular body member 32 of
the bifurcated vascular graft 30 is shown loaded into the graft
body tube 21 which is tapered at its second end 70 in order to
allow for easier movement through the blood vessels and easier
re-entry of the graft body tube 21 into the outermost tube 28.
[0063] The loaded first and second limb tubes 23 and 25 and the
loaded graft body tube 21 are all loaded within the outermost tube
28. The first ends 72 and 74 of the loaded first and second limb
tubes 23 and 25 may lie adjacent the second end 70 of the loaded
graft body tube 21 if the second end 70 of the graft body tube 21
is not tapered. However, if the second end 70 of the graft body
tube 21 is tapered as shown in FIG. 5, the first ends 72 and 74 of
the loaded first and second limb tubes 23 and 25 will not lie in
adjacent vertical alignment with the second end 70 of the graft
body tube 21. Nevertheless, this configuration of the tubes
contained in the deployment apparatus 20 will not affect the
successful deployment of a one-piece bifurcated graft from the
deployment apparatus 20. The first and second limb tubes 23 and 25
may also be dimensioned such that they can both be inserted within
the interior of the graft body tube 21 at the same time.
[0064] A perspective view of the second hollow limb tube 25 of the
deployment apparatus of the present invention is shown in FIG. 6A.
The second hollow tube 25 includes a tapered tip 26, which may be
removable, and a guide wire 27 that is attached to the tapered tip
26. The second hollow tubular limb member 34 of the bifurcated
vascular graft 30 is loaded into the first end 74 of the second
hollow limb tube 25 prior to inserting the deployment apparatus
into a patient's body and implanting the graft 30.
[0065] FIG. 6B shows a partial view of a bifurcated blood vessel 80
shown cut away to illustrate the placement and positioning of the
deployment apparatus 20 of the present invention. Portions of the
outermost tube 28 of the deployment apparatus 20 are also shown cut
away to illustrate the positions of the various other tubes which
comprise the deployment apparatus 20. The first limb tube 23
contains the first hollow tubular limb member 34 of the bifurcated
vascular graft 30, or any other one-piece bifurcated graft, and the
second limb tube 25 contains the second hollow tubular limb member
36 of the bifurcated vascular graft 30, or any other one-piece
bifurcated graft. The first and second limb tubes 23 and 25 lie
parallel to one another and adjacent to the graft body tube 21
which contains the graft body member 32 of the bifurcated vascular
graft 30, or any other one-piece bifurcated graft The first and
second limb tubes 23 and 25 and the graft body tube 21 are all
contained within the outermost tube 28 of the deployment apparatus
20. In FIG. 6B, the outermost tube 28 has been pulled away from the
bifurcation of the blood vessel thereby exposing almost the entire
graft body tube 21. The guide wire 27 which is attached to the
second limb tube 25 is passed to the left side 82 of the bifurcated
blood vessel 80.
[0066] FIG. 7A shows the deployment apparatus 20 of the present
invention in the same position within the blood vessel 80 as that
shown in FIG. 6B with the exception that a longer portion of the
blood vessel 80 is shown to illustrate the position of the entire
graft body tube 21 within the non-bifurcated portion of a
bifurcated blood vessel such as the aorta. Techniques commonly
known in the prior art are used to place the deployment apparatus
20 and the guide wire 27 at the position shown in FIG. 7A. First,
access of both iliac (or femoral) arteries is obtained and sheaths
with homeostatic valves are inserted into the left and right common
femoral (or left and right common iliac) arteries. A separate guide
wire is then passed proximally into the aorta from the right
sheath. Using a "cross-over" technique, an additional guide wire is
brought from the left iliac (or femoral) sheath to the right iliac
(or femoral) sheath. Following this, an angiographic catheter is
passed from left to right over the guide wire. The wire is then
removed, leaving the angiographic sheath protruding from the right
sheath. The right sheath is then removed leaving the angiographic
catheter and the aortic guide wire protruding from the artery
through the patient's skin. Digital pressure is applied for
homeostasis.
[0067] The guide wire 27 contained in the delivery apparatus 20 is
inserted into the angiographic catheter and passed to the sheath in
the left side and withdrawn until at least 2/3 to 3/4 of the wire
27 is on the left side. The deployment apparatus 20 is then loaded
onto the second aortic guide wire on the right side. In a
simultaneous fashion, the deployment apparatus 20 is passed
cephalad on the aortic wire (not shown) within the aorta while the
second wire 27 on the left is withdrawn further to remove the slack
which will occur as the deployment apparatus 20 moves in a cephalad
or proximal manner as shown. Reverse positioning of the guide
wires, catheters and sheaths are carried out when opposite side
deployment is carried out, i.e. when the deployment apparatus 30 is
inserted into the opposite bifurcated blood vessel.
[0068] Under fluoroscopic visualization, when the second limb tube
25 of the deployment apparatus 20 containing the guide wire 27
reaches the aortic bifurcation, all of the slack in the guide wire
27 will be gone and the guide wire 27 will appear as if it is
coming almost straight from the side of the deployment apparatus
20. At that time, the outermost tube 28 is retracted thereby
exposing the first and second limb tubes 23 and 25, which contain
the first and second hollow tubular limb members 34 and 36, as
shown in FIG. 7B. Further traction of the guide wire 27 will then
remove more of the guide wire 27 which is folded upon it self
within the graft body tube 21 as shown in FIG. 6B. Positioning of
the deployment apparatus 20 by further movement of the apparatus 20
in a proximal and distal fashion with further gentle traction of
the guide wire 27 will move the second limb tube 25 through the
bifurcation and into the left iliac artery 82 as shown in FIGS. 7B
through 7C.
[0069] Satisfactory positioning of the deployment apparatus 20 is
obtained using fluoroscopic visualization such that the graft body
tube 21 is located near the bifurcation and below the renal
arteries with the first and second limb tubes 23 and 25 extending
into the right and left iliac arteries 84 and 82. The first and
second hollow tubular limb members 34 and 36 of the bifurcated
vascular graft 30 are deployed by pulling the first and second limb
tubes 23 and 25 distally (or caudad) as shown in FIGS. 7D and 7C.
This process will uncover the first and second hollow tubular limb
members 34 and 36 which have been loaded into the first and second
limb tubes 23 and 25 by compressing the second and third stents 48
and 50 which surround the first and second hollow tubular limb
members 34 and 36, respectively. The self expanding second and
third stents 48 and 50 will then expand to the surrounding vessel
diameter of the right and left iliac arteries 84 and 82. Next, the
first limb tube 23, which is longer than the second limb tube 25,
is retracted back over the metal tube 29 while the second limb tube
25 is pulled through the sheath which still remains on the left
side as previously described above with reference to the "cross
over" technique.
[0070] Next, the ends 59 and 61 of the suture 57 which is sewn to
the second end 40 of the hollow tubular body member 32 of the
bifurcated vascular graft 30 are held firmly for counter traction
while the metal tube 29 attached to the tapered tip 21 of the graft
body tube 21 is pushed in a cephalad direction to expose and deploy
the hollow tubular body member 32 of the bifurcated vascular graft
30. The compressed first stent 42 is thereby released and self
expands to the diameter of the aorta.
[0071] The bifurcated vascular graft 30 of the present invention is
now fully deployed. The first limb tube 23 is then pushed cephalad
into the graft body tube 21 for a variable distance until a tapered
bulb having the same diameter of the graft body tube 21 enters the
caudad end of the graft body tube 21 to form a smooth tapered end
to the graft body tube 21 so that it will retract easily through
the limb members 34 and 36 of the bifurcated vascular graft 30.
[0072] The bifurcated vascular graft of the present invention may
be comprised of any fabric or plastic materials while the stents or
support structures contained in the graft may be comprised of any
suitable biocompatible material capable of strengthening the graft.
The deployment apparatus may be comprised of any suitable
biocompatible material including plastics.
[0073] While the foregoing embodiments of the present invention
have been set forth in detail for the purposes of making a complete
disclosure of the invention, the above-described embodiments of the
invention are intended to be illustrative only. Numerous
alternative embodiments may be devised by those skilled in the art
without departing from the spirit and scope of the following
claims.
* * * * *