U.S. patent application number 10/066436 was filed with the patent office on 2002-07-11 for graft assembly having support structure.
Invention is credited to Baker, Steve G., Dake, Michael D., Dillow, David C., Escano, Arnold.
Application Number | 20020091439 10/066436 |
Document ID | / |
Family ID | 23408154 |
Filed Date | 2002-07-11 |
United States Patent
Application |
20020091439 |
Kind Code |
A1 |
Baker, Steve G. ; et
al. |
July 11, 2002 |
Graft assembly having support structure
Abstract
A delivery catheter having an inner catheter assembly, an
inferior capsule catheter, and a capsule jacket assembly for use in
deploying a graft having a compressible and expandable attachment
systems in the thoracic region of an aorta. The graft is comprised
of a tubular member having superior and inferior ends, each having
an attachment system with wall engaging members secured thereto and
is crimped along its midsection to resist kinking and elongation.
The delivery catheter includes an inferior capsule assembly for
releasably retaining the inferior attachment system of the graft
and a superior capsule assembly for releasably retaining the
superior attachment system of the graft as well as a releasing
system for maintaining the attachment systems in a compressed
configuration and for facilitating expansion of the attachment
systems. The delivery catheter also includes an anti-elongation
wire attached to the inner catheter assembly to prevent stretching
of the delivery catheter during deployment of the graft within the
aorta. Upon removing the attachment systems from the capsule, the
releasing system functions to allow the attachment systems to
assume their expanded configuration and engage the walls of the
aorta. The graft and attachment systems remain in the vessel after
the delivery catheter is withdrawn.
Inventors: |
Baker, Steve G.; (Sunnyvale,
CA) ; Dake, Michael D.; (Stanford, CA) ;
Dillow, David C.; (Cupertino, CA) ; Escano,
Arnold; (San Jose, CA) |
Correspondence
Address: |
FULWIDER PATTON LEE & UTECHT, LLP
HOWARD HUGHES CENTER
6060 CENTER DRIVE
TENTH FLOOR
LOS ANGELES
CA
90045
US
|
Family ID: |
23408154 |
Appl. No.: |
10/066436 |
Filed: |
January 30, 2002 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
10066436 |
Jan 30, 2002 |
|
|
|
08931323 |
Sep 16, 1997 |
|
|
|
6346118 |
|
|
|
|
08931323 |
Sep 16, 1997 |
|
|
|
08358067 |
Dec 15, 1994 |
|
|
|
5693083 |
|
|
|
|
Current U.S.
Class: |
623/1.36 |
Current CPC
Class: |
A61F 2002/3008 20130101;
A61F 2002/8486 20130101; A61F 2002/9511 20130101; A61F 2002/30451
20130101; A61F 2220/0075 20130101; A61F 2002/075 20130101; A61F
2220/0058 20130101; A61F 2/848 20130101; A61F 2/9517 20200501; A61F
2/04 20130101; A61F 2/89 20130101; A61F 2220/0016 20130101; A61F
2250/0098 20130101; A61M 2025/1068 20130101; A61F 2/82 20130101;
A61F 2/966 20130101; A61B 17/11 20130101; A61F 2/07 20130101; A61F
2/95 20130101; A61M 25/10 20130101; A61F 2/958 20130101 |
Class at
Publication: |
623/1.36 |
International
Class: |
A61F 002/06 |
Claims
What is claimed is:
1. A system for repairing a lumen, said system comprising: a graft
having a tubular body, a superior end and an inferior end; a
superior attachment system secured to said superior end of said
graft and an inferior attachment system secured to said inferior
end of said graft, said superior and inferior attachment systems
having a first configuration and a second configuration, said first
configuration compressed from said second configuration; and a
delivery catheter for placing said graft within the lumen, said
delivery catheter having a releasing system, said releasing system
including a superior tie to retain said superior attachment system
in said first configuration and an inferior tie to retain said
inferior attachment system in said first configuration.
2. The system of claim 1, wherein said releasing system further
includes at least one release wire cooperating with said superior
and inferior ties to retain said superior and inferior attachment
systems in said first configuration and to place said superior and
inferior attachment systems in said second configuration.
3. The system of claim 2, wherein said delivery catheter includes
an anti-elongation wire.
4. The system of claim 3, wherein said delivery catheter includes
an inner catheter, an inferior capsule catheter, an inferior
capsule assembly attached to said inferior capsule catheter, and a
superior capsule assembly, said inner catheter disposed within said
inferior capsule assembly, said superior capsule assembly and said
inferior capsule catheter; said inferior capsule catheter, said
superior capsule assembly and said inner catheter assembly each
adapted to move relative to each other; and said superior capsule
assembly adapted to contain said superior attachment system and
said inferior capsule assembly adapted to contain said inferior
attachment system.
5. The system of claim 4, wherein said delivery catheter further
includes a capsule jacket assembly, said capsule jacket assembly
adapted to overlay and move relative to said inferior capsule
catheter, said superior capsule assembly and said inner
catheter.
6. The system of claim 4, wherein said inner catheter includes a
control wire lumen adapted to slidably receive a control wire, said
control wire having a distal end secured to said superior capsule
assembly.
7. The system of claim 4, wherein said superior capsule assembly
includes a flexible and tapered nose cone.
8. The system of claim 4, wherein said inner catheter includes an
anti-elongation lumen adapted to receive said anti-elongation wire
and at least one notch in communication with said anti-elongation
lumen, said anti-elongation wire adapted to exit said
anti-elongation lumen through said notch and to be affixed to an
exterior of said inner catheter.
9. The system of claim 4, wherein said inner catheter includes a
release wire lumen adapted to receive said release wire and at
least one notch in communication with said release wire lumen, said
release wire exiting said release wire lumen through said at least
one notch to engage said tie and to reenter said release wire lumen
through said notch.
10. The system of claim 9, wherein said inner catheter includes a
conical-shaped knob cooperating with said superior capsule assembly
for retracting said superior capsule assembly through said
graft.
11. The system of claim 4, wherein said inner catheter includes a
release wire lumen, said release wire slidably disposed in said
release wire lumen, an inferior notch and a superior notch each in
communication with said release wire lumen, said release wire
exiting said inferior notch, engaging said inferior tie and
reentering said inferior notch, said release wire further exiting
said superior notch, engaging said superior tie and reentering said
superior notch.
12. The system of claim 11, wherein said superior and inferior ties
each include a single suture, each said suture secured at a
midpoint to said graft, formed into two loops through which said
release wire is threaded and affixed at their ends to said
graft.
13. The system of claim 12, wherein each said suture is secured to
said graft so that each said suture resides exterior said
graft.
14. The system of claim 13, wherein said release wire passes
through a wall of said graft near said inferior end of said graft
to engage said inferior tie and passes through said wall of said
graft near said superior end of said graft to engage said superior
tie.
15. The system of claim 13, wherein each said suture is passed
through a wall of said graft to engage said release wire.
16. A graft for intraluminal repair of a thoracic aortic aneurysm,
comprising: a hollow tubular body, a superior end and an inferior
end, said hollow tubular body having a predetermined diameter,
length and wall thickness adapted for intraluminal repair of a
thoracic aortic aneurysm.
17. The graft of claim 16, wherein said predetermined diameter
ranges from 30-40 mm.
18. The graft of claim 16, wherein said predetermined length ranges
from 7-15 cm.
19. The graft of claim 16, wherein said predetermined wall
thickness ranges from 0.127 to 0.229 mm.
20. A method for placing a graft within a lumen, which comprises
the steps of: providing a graft having an attachment system secured
thereto, said attachment system having a first configuration and a
second configuration, said first configuration compressed from said
second configuration; providing a delivery catheter for receiving
said graft and for placing said graft within the lumen, said
delivery catheter having a releasing system cooperating with said
attachment system, said releasing system including a tie and a
release wire; placing said release wire into engagement with said
tie; causing said tie to place said attachment system in said first
configuration; loading said graft within said delivery catheter;
placing said delivery catheter within the lumen; unloading said
graft from said delivery catheter; and removing said release wire
from engagement with said tie to permit said attachment system to
assume said second configuration and to engage the lumen.
21. A method for repairing a thoracic aortic aneurysm, which
comprises the steps of: providing a graft having an attachment
system secured thereto, said attachment system having a first
configuration and a second configuration, said first configuration
compressed from said second configuration; providing a delivery
catheter for receiving said graft and for placing said graft within
the thoracic aorta, said delivery catheter having a releasing
system; causing said releasing system to retain said attachment
system in said first configuration; loading said graft within said
delivery catheter; placing said delivery catheter within a
patient's vasculature; advancing said delivery catheter to the
thoracic aorta; unloading said graft from said delivery catheters;
and causing said releasing system to permit said attachment system
to assume said second configuration and to engage said thoracic
aorta.
Description
[0001] This application is a continuation-in-part of application
Ser. No. 102,576 filed Aug. 5, 1993, which is a
continuation-in-part of application Ser. No. 553,530 filed on Jul.
13, 1990, which is a continuation-in-part of application Ser. No.
166,093 filed on Mar. 9, 1988, now U.S. Pat. No. 5,104,399, which
is a continuation-in-part of application Ser. No. 940,907 filed on
Dec. 10, 1986, now U.S. Pat. No. 4,787,899 which is a continuation
of application Ser. No. 559,935 filed on Dec. 9, 1983, now
abandoned. The contents of each of these applications are hereby
incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] This invention relates to a system for implanting a
prosthesis, and more particularly, to a delivery catheter for
placing a graft having an attachment system within a corporeal
lumen.
[0003] It is well established that various fluid conducting body or
corporeal lumens, such as veins and arteries, may deteriorate or
suffer trauma so that repair is necessary. For example, various
types of aneurysms or other deteriorative diseases may affect the
ability of the lumen to conduct fluids and, in turn, may be
life-threatening. In some cases, the damaged lumen is repairable
only with the use of a prosthesis such as an artificial vessel or
graft. For repair of vital vessels such as the aorta, repair may be
significantly life-threatening. Techniques known in the art which
tend to minimize dangers to the patient include a procedure in
which a graft resembling the natural vessel is placed within the
diseased or obstructed section of the natural vessel.
[0004] More specifically, it is known within the art to provide a
prosthesis for intraluminal repair of a vessel. In intraluminal
vessel repair, the prosthesis is advanced intraluminally through
the vessel to the repair site using a delivery catheter and
deployed within the vessel so that the prosthesis traverses the
diseased portion to thereby repair the vessel.
[0005] Generally speaking, varied concerns arise when repairing the
different deteriorated disease that may affect a vessel. For
instance, thoracic aneurysms differ from other aortic aneurysms in
several respects. As may well be expected, due to their proximity
to the heart, there are concerns specific to thoracic aneurysms
that are not evident in the repair of other types of aortic
aneurysms. Moreover, the size and shape of the thoracic aneurysms
differ and are often more varied than other types of aortic
aneurysms
[0006] In particular, thoracic aneurysms are often close to what
are typically called the great arteries, such as the left
subclavian artery, or may be found to occur proximal to the celiac
trunk. These lumens, which branch away from the thoracic region of
the aorta, are critical to the body's circulatory system and carry
high volumes of blood to various parts of the body. Consequently,
these lumens generally cannot be occluded by a prosthesis used to
intraluminally repair a thoracic aneurysm unless additional
procedures are performed to bypass the occluded lumen.
[0007] In addition, thoracic aneurysms have diameters that are
typically larger and have shapes perhaps more variable than other
aortic aneurysms. The average neck diameter of thoracic aneurysms
is on the order of 34-36 mm and the average length approximately 10
cm with a range of 5-16 cm. To complicate matters, due to the
curvature of the aortic arch, the superior neck of thoracic
aneurysms are often at a different angle from that of the inferior
neck. Also, among the myriad of shapes they may take on, thoracic
aneurysms may be fusiform in shape, or comprise giant penetrating
ulcers.
[0008] Further, access to thoracic aneurysms through connecting
arteries is limited and methods for implanting a prosthesis must
take into account the physiology of and effects to the heart.
Specifically, the femoral as well as the iliac arteries may be too
narrow to pass a catheter for delivering a thoracic prosthesis or
graft. Often, surgical repair of a thoracic aortic aneurysm
requires thoracotomy. Also, it is not desirable for catheters
delivering a thoracic graft to comprise a balloon since the use of
the balloon to implant the graft would temporarily stop blood flow,
thereby placing potentially dangerous loads upon the heart.
Finally, due to high pressures existing in the area of a thoracic
aneurysm, the attachment system of a graft for repairing a thoracic
aneurysm must be sufficient to prohibit migration of the graft. It
is also to be noted that there is typically a lack of calcification
in the area of thoracic aneurysms. Consequently, the attachment
systems of grafts for repairing thoracic aneurysms generally need
not be placed within the lumen with forces overcoming such
hardening of tissue.
[0009] Thus, what has been needed and heretofore unavailable is a
graft and a delivery catheter system therefor, wherein the graft is
designed specifically to repair thoracic aortic aneurysms and the
delivery system functions to precisely position a graft within an
aorta to thereby completely repair the thoracic aneurysm. The graft
is to be configured to conform to the various possibilities of
shapes of the thoracic aneurysm and to have an attachment system
which effectively affixes the graft within the aorta. In addition,
the delivery catheter is to effectively operate within the unique
anatomical constraints of the thoracic portion of the aorta. The
present invention accomplishes these goals.
SUMMARY OF THE INVENTION
[0010] Briefly, and in general terms, the present invention
provides a new and improved graft and delivery catheter and a novel
method for their use in repairing a lumen. The graft is configured
for repairing a diseased condition of the lumen. The delivery
catheter is configured to introduce the graft within or between
vessels or corporeal lumens of an animal, such as a human, and to
facilitate the deployment of the graft at the repair sites.
[0011] The present graft has a diameter that is larger than that of
conventional grafts so that relatively larger lumens may be
repaired and its walls are thinner to facilitate packing it within
the delivery catheter. The attachment system of the present graft
is expandable and is stiffer and has hooks with greater angles from
radial than conventional attachment systems. Also, in addition to
being secured to the ends of the graft, the attachment system is
secured by its apices to the graft to prevent relative motion of
the attachment system and graft. Further, the novel attachment
system of the present graft enables it to self expand quickly and
forcefully without the aid of a balloon catheter as well as enables
it to securely hold the graft within lumens carrying high volume of
blood.
[0012] The present delivery catheter includes structure for quickly
deploying the graft within the lumen to be repaired. Further, by
not employing a balloon catheter, the delivery catheter may be
utilized to repair lumens located near the heart without placing
undue stress on the heart and is configured for packing a larger
diameter graft within the delivery catheter. Additionally, the
delivery catheter is configured to hold the attachment systems
affixed to the ends of the graft within capsules and by not placing
the entire graft within a single capsule, larger diameter grafts
may be packed within the delivery catheter. Moreover, the delivery
catheter is longer which enables it to reach an aortic arch and
employs a novel releasing system cooperating with the capsules
which, in conjunction, operate to facilitate loading as well as
deployment of the graft. The releasing system includes a release
wire cooperating with releasable ties attached to the exterior of
the graft to maintain the attachment systems of the graft in a
collapsed configuration and to facilitate the expansion of the
attachment systems so that they properly and quickly engage the
walls of the lumen.
[0013] The present invention provides a prosthesis or graft for
intraluminal placement in a fluid conducting corporeal lumen. The
graft is hollow and has a pre-selected cross-section, length and
wall thickness. The graft is deformable to conform substantially to
the interior surface of the corporeal lumen or other body part to
be repaired. The midsection of the graft may be crimped to resist
kinking and facilitate placement accuracy and may comprise
radiopaque markers attached along its length to help orient the
graft using fluoroscopy or X-ray techniques. Tufts of yarn are sewn
into the graft at its ends to facilitate healing and placement of
the graft within the corporeal lumen. Preferably, the graft
comprises woven polyester or another material suitable for
permanent placement in the body such as PTFE. The superior and
inferior ends of the graft are positioned within the corporeal
lumen and the graft is configured such that it traverses the
diseased or damaged portion of the vessel. To anchor the graft to
the wall of the corporeal lumen, attachment systems are secured to
the superior and inferior ends of the graft.
[0014] The preferred attachment system includes wall engaging
members. The wall engaging members of the superior attachment
systems are angled toward the inferior end of the graft. Similarly,
the wall engaging members of the inferior attachment systems are
angled toward the superior end of the graft. Specifically, the
angles of both the superior and inferior wall engaging members are
in the range of 60-80.degree. from radial. The wall engaging
members of both attachment systems have sharp tips for engaging the
corporeal lumen wall. The preferred attachment systems are formed
into a staggered V-shape lattice or framework, the apices of which
comprise helical torsion springs. The frame of the attachment
systems allows for elastic radial deformation resulting in a
spring-like effect when a compressed attachment system is allowed
to expand as the graft is released from the capsules, and by having
a high stiffness, they function to quickly and forcefully seat the
graft within the lumen.
[0015] Preferably, the delivery catheter of the present inventor is
flexible and includes an elongate cylindrical jacket overlaying a
superior capsule assembly and an inferior capsule assembly, each of
which are adapted to releasably retain an end of the graft. The
superior capsule assembly further includes an elongated flexible
conical-shaped or tapered nose cone adapted to facilitate the
advancement of the delivery catheter through a patient's
vasculature. Attached at the most proximal end of the inferior
capsule assembly is an elongate outer shaft, comprising an inferior
capsule catheter, which is adapted to receive a multi-lumen inner
shaft. The lumens of the inner shaft are conduits for a guidewire,
one or two release wires, an anti-elongation wire and a control
wire that cooperates with the superior capsule assembly. Attached
to the inner shaft and distal to the outer shaft/inferior capsule
assembly junction is a conical-shaped knob that cooperates with the
superior capsule assembly. Also attached to the inner shaft is an
anti-elongation wire that functions to minimize elongation of the
inner shaft during deployment of the graft. The jacket is capable
of moving relative to the rest of the catheter and thus can be
withdrawn, thereby exposing the capsules and graft. Similarly, the
capsules can be caused to move relative to the inner shaft and the
structure attached thereto, which, in conjunction with the
operation of the releasing system, thereby causes the deployment of
the graft within a lumen. The length of the delivery catheter is
sufficient for use in reaching the thoracic portion of the aorta
and has a diameter suited for encasing a graft for use in repairing
a thoracic aneurysm.
[0016] Deployment of the graft comprises a series of steps which
begins with introducing the delivery catheter into the corporeal
lumen using well known surgical techniques. The delivery catheter
is manipulated so that the graft retained by the superior and
inferior capsule assemblies is positioned at a desired location
within the corporeal lumen. Once the graft is in the desired
location, the jacket is retracted and the superior and inferior
capsule assemblies are removed from the graft to expose the
superior and inferior attachment systems of the graft. After this
is accomplished, the releasing system is employed to thereby allow
the attachment systems self-expand and seat the graft within the
lumen.
[0017] Two methods are contemplated for placing the graft within a
lumen. As a first step in each method, the jacket is moved
proximally to expose the graft retained by the superior and
inferior capsules. In the first method, the superior capsule
assembly is moved distally to expose the superior end of the graft
and the inferior capsule assembly is moved proximally to expose the
inferior end of the graft. The releasing system is then employed to
release the superior attachment system, thereby allowing the
superior attachment system to affix the superior end of the graft
within the lumen. Thereafter, the releasing system is employed to
release the inferior attachment system to thereby allow the
inferior attachment system to affix the inferior end of the graft
within the lumen. In the second method, these steps are reordered
so that the inferior end of the graft is first seated within the
lumen and thereafter, the superior end is seated.
[0018] Other features and advantages of the present invention will
become apparent from the following detailed description, taken in
conjunction with the accompanied drawings, which illustrate, by way
of example, the features of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is a top plan view of the delivery catheter and graft
incorporating the present invention.
[0020] FIG. 2 is a top plan view of a an anti-elongation wire of
the present invention.
[0021] FIG. 3 is a top plan view of a release wire of the present
invention.
[0022] FIG. 4 is a top plan view of a guidewire to be used with the
delivery catheter of the present invention.
[0023] FIG. 5 is a top plan view of an inner catheter assembly of
the present invention.
[0024] FIG. 6 is a top plan view of a superior capsule assembly,
control wire, hypotube and control wire handle assembly of the
present invention.
[0025] FIG. 7 is a top plan view of an inferior capsule and capsule
catheter of the present invention.
[0026] FIG. 8 is a top plan view of a capsule jacket assembly of
the present invention.
[0027] FIG. 9 is a top plan view of a graft for use with the
delivery catheter of the present invention.
[0028] FIG. 10 is a cross-sectional view taken along the line 10-10
of FIG. 1.
[0029] FIG. 11 is an alternate embodiment of the view depicted in
FIG. 10.
[0030] FIG. 12 is a partial cross-sectional view of the inferior
capsule, superior capsule and capsule jacket assemblies and the
anti-elongation wire, release wire and graft.
[0031] FIG. 13 is an enlarged perspective view showing a presently
preferred embodiment of the distal end of the control wire,
superior cap insert, superior cap and nose cone.
[0032] FIG. 14 is an enlarged cross-sectional view of the superior
capsule assembly.
[0033] FIG. 15 is a cross-sectional view taken along the line 15-15
of FIG. 14.
[0034] FIG. 16 is a partial cross-sectional view of the control
wire and control handle mechanism of FIG. 1.
[0035] FIG. 17 is a cross-sectional view taken along the line 17-17
of FIG. 16.
[0036] FIG. 18 is a cross-sectional view taken along the line 18-18
of FIG. 16.
[0037] FIG. 19 is a cross-sectional view taken along the line 19-19
of FIG. 16.
[0038] FIG. 20 is a cross-sectional view taken along the line 20-20
of FIG. 16.
[0039] FIG. 21 is a partial cross-sectional view of the graft and
attachment system of the present invention.
[0040] FIG. 22 is a cross-sectional view taken along the line 22-22
of FIG. 21.
[0041] FIG. 23 is an enlarged perspective view showing a superior
attachment system.
[0042] FIG. 24 is an enlarged perspective view showing an inferior
attachment system.
[0043] FIG. 25 is a perspective view showing an alternate
embodiment of the graft.
[0044] FIG. 26 is an enlarged perspective view showing an alternate
embodiment of the wall engaging members of the attachment
system.
[0045] FIG. 27 is an enlarged perspective view showing an alternate
embodiment of the wall engaging member of the present
invention.
[0046] FIG. 28 is an enlarged perspective view showing another view
of the alternate embodiment of FIG. 27.
[0047] FIG. 29 is a perspective view showing another embodiment of
the graft.
[0048] FIG. 30 is a cross-sectional view of the graft depicted in
FIG. 29.
[0049] FIG. 31 is a perspective view showing yet another embodiment
of the graft.
[0050] FIG. 32 is a cross-sectional view of the graft depicted in
FIG. 31.
[0051] FIG. 33 is a partial cross-sectional view of the delivery
catheter and graft, illustrating a releasing system of the delivery
catheter.
[0052] FIG. 34 is a cross-sectional view taken along the line of
34-34 of FIG. 33.
[0053] FIG. 35 is a partial cross-sectioned view of the delivery
catheter and graft, illustrating another embodiment of the
releasing system of the delivery catheter.
[0054] FIG. 36 is a partial cross-sectional view of the delivery
catheter and graft positioned within the corporeal lumen.
[0055] FIG. 37 is a partial cross-sectional view of the delivery
catheter and graft shown in FIG. 33, wherein the capsule jacket has
been retracted proximally relative to the delivery catheter.
[0056] FIG. 38 is a partial cross-sectional view of the delivery
catheter and graft shown in FIG. 34, wherein the superior capsule
assembly has been removed from the superior end of the graft.
[0057] FIG. 39 is a partial cross-sectional view of the delivery
catheter and graft shown in FIG. 35, wherein the inferior capsule
has been removed from the inferior end of the graft.
[0058] FIG. 40 is partial cross-sectional view of the delivery
catheter and graft shown in FIG. 36, wherein the release system has
been used to facilitate emplacement of the superior attachment
system within the corporeal lumen.
[0059] FIG. 41 is a partial cross-sectional view of the delivery
catheter and graft shown in FIG. 37, wherein the release system has
been utilized to facilitate emplacement of the inferior attachment
system within the corporeal lumen.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0060] As is shown in the drawings and for purposes of
illustration, the invention is embodied in a thoracic graft and a
delivery catheter therefor. One of the novel features of the
present invention is the attachment system of the graft which
operates to securely affix the graft within a lumen without the aid
of a balloon catheter. Another novel feature of the present
invention is the releasing system which functions to release the
attachment systems of the graft once the graft has been advanced
within the vasculature of the patient to the repair site.
[0061] Generally, in the present invention, the graft is comprised
of a monoluminal tubular member having superior and inferior
extremities. Expandable attachment systems are secured to the
superior and inferior ends of the tubular member. The attachment
systems are provided with wall engaging members which are covered
by the inferior and superior capsule assemblies. The delivery
catheter includes a plurality of elongate components which are
configured coaxially so that relative movement between them
provides for deployment of the graft.
[0062] In more detail, the delivery catheter 50 is shown in FIGS.
1-8. As shown in FIG. 1, the delivery catheter 50 includes an inner
catheter assembly 51, which is coaxially disposed within an
inferior capsule catheter 52, which is coaxially disposed within
the capsule jacket 53. Also disposed about the inner catheter is a
superior capsule assembly 90. Attached to the inferior capsule
catheter 52 is an inferior capsule assembly 130. The inferior
capsule assembly 130 and the superior capsule assembly 90 are used
to contain the attachment systems of the graft 55. A control wire
assembly 54 (see FIG. 6) is coaxially disposed within one of a
plurality of lumens of an inner shaft 61 included in the inner
catheter assembly 51 and is configured to move the superior capsule
assembly 90 in relation to the other components. In the preferred
embodiment, the system is used as an over-the-wire device, such
that the delivery catheter 50 is further configured with a lumen
for a guidewire 56 (see FIG. 4). It is contemplated, however, that
the system can also be used with a well known fixed wire delivery
configuration.
[0063] Moreover, the delivery catheter 50 includes a release wire
57 (see FIG. 3). The release wire 57 comprises a portion of a
releasing system of the delivery catheter 50. The release wire 57
is adapted to be disposed within one of the plurality of inner
shaft 61 lumens and cooperates with structure attached to the graft
55 to maintain the attachment systems of the graft 55 in a
collapsed configuration (see FIG. 12) as well as to facilitate the
timely expansion of the attachment systems so that the graft 55 may
be implanted in a lumen. Preferably, the release wire 57 has a
diameter of approximately 0.010 inches and a length on the order of
100 cm, so that its inferior end 77 may be manipulated by the
operator yet be long enough to extend beyond the repair site. In a
presently preferred embodiment, the inferior end 77 of the release
wire 57 is attached to a rotating knob (not shown) so that when the
knob is rotated, the release wire 57 wraps around the knob thereby
causing it to move proximally relative to the other components of
the deliver catheter 50. It is also contemplated that, in the
alternative, the inferior end 77 of the control wire 57 is adapted
to be gripped by the operator. The release wire 57 may be made from
FEP coated nitinol.
[0064] Additionally, the delivery catheter includes an
anti-elongation wire 59 (see FIG. 2). The anti-elongation wire 59
cooperates with the inner shaft 61 to prevent stretching of the
inner shaft 61 during deployment of the graft 55 within the lumen.
A superior end 79 of the anti-elongation wire 59 is attached to the
inner shaft 61. An inferior portion 78 is similarly attached to the
inner shaft 61. The anti-elongation wire 59 may be disposed within
a lumen of the inner shaft 61 or may be positioned along side the
inner shaft 61. Preferably, the diameter of the anti-elongation
wire 59 is approximately 0.008 inches. In one presently preferred
embodiment, the anti-elongation wire 59 is made from kevlar yarn
but it can also be made of stainless steel.
[0065] As shown in FIG. 10, the inner shaft 61 is preferably
configured with multiple lumens; however, the inner shaft 61 may be
configured with a single or a plurality of lumens. A guidewire
lumen 63 extends the length of the inner shaft 61. A release wire
lumen 64 also extends the length of the inner shaft 61. A control
wire lumen 65 is provided for a control wire 91 included in the
control wire assembly 54 and also extends the length of the inner
shaft 61. In an alternative embodiment, the inner shaft 61 also
includes an anti-elongation lumen 66 extending its length (see FIG.
11). Additionally, as will be hereinafter discussed in more detail,
the inner shaft 61 may include a plurality of reinforcing bands,
low profile projections or bumps and slits.
[0066] The flexible elongate element of the inner shaft 61 is
preferably formed of a material suitable for intraluminal use, such
as crosslinked polyethylene tubing. The multi-lumen shaft 61 is
preferably extruded to an outer diameter of 0.08 inches (2.03 mm).
The guidewire lumen 63 has an inner diameter of 0.040 inches (1.02
mm). The release wire lumen 64 and the control wire lumen 65 each
have a diameter of 0.022 inches (0.56 mm) but may range from 0.015
to 0.030 inches (0.381-0.762). The outside diameter may range from
0.035 to 0.1 inches (0.889-2.54 mm). In the embodiment of the inner
shaft 61 that includes the anti-elongation lumen 66, the
anti-elongation lumen 66 may have a diameter of at least 0.008
inches. The inner shaft 61 may vary in length to suit the
application, for example, from 50-150 cm.
[0067] As shown in FIGS. 5 and 12, a conical-shaped knob 100 is
affixed to inner shaft 61. As will be developed below, the
conical-shaped knob 100 cooperates with the graft 55 and superior
capsule assembly 90 to facilitate emplacement of the graft 55
within a lumen. The inner shaft 61 also includes two release wire
notches 102, 104 which provide a space for the release wire 57 to
exit and reenter the release wire lumen 64. By providing such a
space, the release wire 57 can exit the inner shaft 61 and be
placed into engagement with the structure attached to the graft 55
which function to control whether the attachment systems of the
graft are in their collapsed or expanded configuration. In one
presently preferred embodiment, each notch 102, 104 is flanked by
reinforcing bands (not shown) which add structural reinforcement to
the inner shaft 61 to prevent elongation of the notches 102, 104 as
well as low profile bumps (not shown) formed on the inner shaft 61
which aid in keeping the reinforcing bands in place. Preferably,
the material of the reinforcing bands is selected so that they
perform as radiopaque markers. Further, additional bumps (not
shown) may be formed on the inner shaft 61 to cooperate with the
superior capsule assembly 90 to limit its proximal and distal
movement.
[0068] The delivery catheter also includes the control wire
assembly 54, which is shown in FIGS. 1 and 6. The distal end of the
control wire assembly 54 consists of the superior capsule assembly
90. As shown in more detail in FIGS. 13-15, the superior capsule
assembly 90 may comprise a control wire 91 secured within a
superior cap insert 96 that is placed within a superior cap 92. The
superior cap 92 includes a threaded male portion that is received
in a nose cone 94 having a threaded female portion. The nose cone
94 is flexible and has an elongated conical or tapered shape
adapted to facilitate advancement of the delivery catheter 50
through a patient's vasculature. A hollow superior capsule 93 is
secured to the superior cap 92 and coaxially surrounds the control
wire.
[0069] As shown in FIG. 12, the conical-shaped knob 100 is secured
to the inner shaft 61 and may be positioned within superior capsule
93 at a location adjacent and proximal to the superior cap 92. As
the control wire is moved in a longitudinal manner, the superior
end of the control wire 95, the superior cap insert 96, the
superior cap 92, the nose cone 94 and the superior capsule 93 each
move as a single assembly (see also FIG. 14).
[0070] The nose cone 94 may be made from PEBAX and the superior cap
92 may be formed from polycarbonate or other suitable material for
insertion through the body lumen. The nose cone 94 is formed with a
bore 104 of approximately the same diameter as the outer diameter
of the inner shaft 61. Similarly, the superior cap insert 96 may be
formed of the same material as the superior cap 92, wherein the
superior cap insert 96 is provided with a bore 105 for receiving
the inner shaft 61. The superior cap 92 is further provided with a
recess 106 or other means for receiving the superior end of the
superior capsule 93. The superior capsule 93 is preferably formed
of stainless steel, but may be formed of other suitable
biocompatible material, such as a nickel titanium. The superior cap
recess 106 is angled to allow crimping of the superior capsule 93
to the superior cap 92.
[0071] The outside diameter of the superior capsule 93 may range
from 4-9 mm and is preferably 0.289 inches (7.3 mm) in outer
diameter and 0.276 inches (7.01 mm) inner diameter. The length of
the superior capsule 93 is approximately 0.87 inches (22 mm).
[0072] FIGS. 13-15 show a presently preferred embodiment of the
superior capsule assembly 90. In this embodiment, the control wire
91 is threaded through an opening 107 in the superior cap insert
96. A longitudinal slot 109 is cut out in the inner shaft 61 to
expose the control wire lumen 65. The control wire is formed in a
U-shaped bend over the opening in the superior cap insert and is
configured to slide within the slot and in the inner shaft lumen
65. The distal end of the control wire 95 resides in the superior
cap insert 96. This configuration allows the superior cap assembly
to move axially along the inner catheter shaft. The U-shaped bend
of the control wire through the superior cap insert, however,
prevents the superior cap assembly from rotating in relation to the
inner catheter shaft. As described above, the superior cap insert
is firmly secured within the superior cap.
[0073] It is to be understood that other embodiments of the
superior capsule assembly are contemplated. For instance, the
control wire may be configured to pass through the superior capsule
assembly, by way of the inner shaft lumen 65, and be attached at a
superior end of the superior cap. Irrespective of the embodiment,
however, it is contemplated that the control wire causes relative
movement of the superior capsule assembly and the inner shaft.
[0074] As shown in FIGS. 16-20, a handle assembly 110 is secured to
the proximal end of the control wire 91. The handle assembly
comprises a proximal body 111, a distal body 112, a control knob
113 with rotating shaft 114 and a hypotube 115. The two handle body
parts have a central bore 119 for receiving the inner shaft 61. A
retaining pin 129 may be used to secure the two pieces of the
handle body together. It is also contemplated that the handle
assembly 110 include one or more release wire knobs (not shown),
each having a rotating shaft adapted to be attached to a release
wire. Upon rotation of a release wire knob, it is contemplated that
the release wire wraps around the rotating shaft to thereby cause
the release wire to retract.
[0075] The hypotube 115 is coaxially disposed over the inner shaft
61 and extends distally from the central bore 119 in the distal
handle body 112. The proximal end of the hypotube is secured to the
inner shaft 61 approximately one centimeter proximal from the
distal end of the distal handle body by means of a polyethylene
sealing tube 116 which is heat shrunk over the proximal end of the
hypotube. An adhesive may be used to fix the distal handle body to
the hypotube.
[0076] Hypotube 115 consists of a rigid thin wall tube formed of a
suitable material such as stainless steel. The hypotube has a
length of about 55 centimeters and has an outside diameter of 0.095
inches (2.41 mm) and an inside diameter of 0.087 inches (2.21 mm).
When a crimped graft 55 is used, the hypotube may have marker bands
(not shown) at predetermined positions distal of the control handle
body 112. The marker bands facilitate the correct positioning of
the inferior end of the graft.
[0077] Referring to FIG. 16, the control wire 91 resides in an
inner shaft lumen 65 and extends from the superior capsule assembly
90 to an aperture 117 located in the lumen just proximal of the
proximal end of the hypotube 115. The control wire preferably
consists of an elongate solid flexible stainless steel wire having
a lubricating coating, such as fluorinated ethylene-propylene
(FEP). The coated control wire is about 0.02 inches (0.508 mm) in
diameter, providing sufficient strength to move the inferior
capsule assembly without buckling or kinking.
[0078] The proximal end of the control wire 91 is disposed within a
retaining rack 120, approximately six centimeters long and having a
central bore to secure the control wire. The proximal end of the
retaining rack 120 is slidably disposed within a longitudinal
guiding slot 121 in the proximal handle 111. Similarly, the distal
end of the retaining rack 120 is slidably disposed within an
longitudinal slot 122 in the distal handle body 112.
[0079] The retaining rack 120 is configured with teeth 123 along a
longitudinal edge which engage a pinion or gear 124. The pinion is
attached to a lower end of the rotating shaft 114. The upper end of
the rotating shaft is secured within the control knob 113 such that
rotation of the control knob rotates the gear and in turn moves the
retaining rack longitudinally within the guiding slots.
Longitudinal movement of the retaining rack causes longitudinal
movement of the proximal end of the control wire 91, causing like
longitudinal movement of the distal end 95 of the control wire and
of the superior capsule 93. As shown in FIGS. 17 and 19, a locking
screw 118 is configured to fix the retaining rack in place. The
locking screw ensures that the control wire and superior capsule
will not move even if torque is applied to the control knob.
[0080] At the base of the control knob 113 is a locking gear 125
which has curved teeth. The curved teeth engage a locking pin 126
biased by a locking spring 127 disposed within a recess 128 in the
upper surface of the proximal body 111 of the control handle 110.
The configuration of the curved teeth allows the control knob to
turn in only one direction while the locking pin engages the
locking gear. When the locking pin is moved to compress the locking
spring, then the control knob may be turned in either direction.
The locking gear is preferably molded as part of a plastic control
knob, but may be a separate mechanism secured to the base of the
control knob.
[0081] As shown in FIGS. 1 and 7, the inferior capsule catheter 52
consists of an inferior capsule assembly 130 secured to the distal
end of a flexible elongate outer shaft 131 formed of a suitable
plastic material such as polyether block amide available under the
trademark "PEBAX", available from Atochem Polymers, Glen Rock, N.J.
The outer shaft member 131 is of a suitable length as, for example,
40 to 100 centimeters and preferably approximately 85 centimeters
for the thoracic aortic artery. The outer shaft has a preferred
outside diameter of 0.187 inches (4.75 mm) and an inside diameter
of 0.125 inches (3.175 mm). The outer shaft can be produced in a
certain color such as blue. To render the outer shaft radiopaque
under x-rays, its material of construction may contain a radiopaque
material, such as twenty percent by weight of bismuth subcarbonate
or barium sulfate. The outer shaft may have markings or bands
distal of the wye adapter 145 at predetermined positions to
indicate capsule jacket retraction and locking points.
[0082] The inferior capsule assembly 130 has an inferior capsule
132 mounted on the distal extremity of the outer shaft member 131.
The inferior capsule has a preferred diameter ranging from 4 to 9
millimeters, which may be configured to accommodate different size
grafts. The length of the inferior capsule 132 is approximately
0.709 inches (18 mm). The inferior capsule is configured to match
the size of the superior capsule assembly 90. The inferior capsule
is preferably made of stainless steel or similar impermeable and
rigid, or semi-flexible material. The outer shaft member also
serves as a shaft for advancing the inferior capsule, as
hereinafter described. Thus, the outer shaft member should have a
diameter which is less than that of the inferior capsule.
[0083] Referring to FIG. 12, the inferior capsule 132 is secured to
the distal extremity of the outer shaft member 131 by means of a
capsule adapter assembly 133. The capsule adapter assembly
comprises a housing 134 and an inner sleeve 135, which may be
constructed from polycarbonate. The capsule adapter housing distal
extremity 136 is secured in the proximal extremity of the capsule,
for example, by crimping, by using a press fit swaging or an
adhesive such as a cyanoacrylate ester. The capsule adapter housing
distal extremity may be angled to facilitate securing the housing
to the inferior capsule.
[0084] The proximal extremity of the capsule adapter housing 134 is
secured to the distal extremity of the outer shaft member 131 by
means of an cyanoacrylate ester adhesive, or other suitable means.
To facilitate a mechanical lock, the outer shaft distal extremity
is molded to form a flange 137, wherein the capsule adapter housing
is configured so as to close around the flange. The capsule adapter
housing is further provided with a recess for receiving the capsule
adapter inner sleeve 135. The inner sleeve is provided with a bore
of a suitable diameter so as to allow the inner shaft 61 to reside
therein.
[0085] A wye adapter 145 (see FIG. 7) is secured to the proximal
extremity of the outer shaft member 131 of the inferior capsule
catheter 52. The central arm 146 of the wye adapter is connected to
a Touhy Borst adapter 147 which tightens around the guiding member
115 disposed in the central arm of the wye adapter. The side arm
148 of the wye adapter has a stop cock 149 mounted therein which is
movable between open and closed positions. The stop cock is
provided with a Luer fitting 150 which is configured to accept a
syringe for injecting a radiopaque contrast. Air may be purged from
the capsule jacket assembly 53 by injecting fluid through the Luer
fitting. The injection fluid will exit purge ports 151 and 152,
thereby filling the capsule jacket assembly with injection fluid.
The Luer fitting may be attached to a saline drip line during the
operative procedure.
[0086] Referring to FIGS. 1, 8 and 12, the capsule jacket assembly
53 is slidably disposed coaxially over the inferior capsule
catheter 52 and the inner catheter assembly 51. The capsule jacket
assembly is comprised of a main jacket 160, and a locking connector
162. The main jacket diameter changes at a point approximately 15
centimeters from the distal end 163, depending on the length of the
graft 55. The main jacket flares to an expanded diameter to cover
the graft 55, the inferior capsule 132 and the superior capsule 93.
The proximal ends of the jacket may be secured to the jacket
adapter 164 of the locking connector by mechanical means and by
adhesive.
[0087] When the capsule jacket assembly 53 is in its most distal
position, the distal end 163 of the capsule jacket extends to cover
at least a portion of the superior capsule assembly 90. Similarly,
the capsule jacket locking connector 162 is thereby positioned
proximal to the inferior capsule catheter purge port 151. Prior to
insertion into the lumen, locking ring 165 (not shown) is turned to
hold the capsule jacket assembly firmly in place, thereby
maintaining a smooth transition surface along the length of the
delivery catheter 50 which resides in the body vessels. When the
locking ring is released, the capsule jacket assembly may be moved
to a furthermost proximal position, wherein at least a portion of
the inferior capsule assembly 130 is exposed. Thus, the locking
connector is positioned just distal to the capsule catheter wye
adapter 145. The locking ring may be tightened at any intermediate
position to firmly secure the capsule jacket assembly at the
desired location. In addition, a radiopaque marker 166 is provided
at the distal end of the main jacket to facilitate proper linear
positioning of the capsule jacket.
[0088] As shown in FIGS. 1 and 9, the present invention includes an
expandable intraluminal vascular graft 55 for implanting in a body
vessel. Referring to FIG. 21, the graft consists of a deformable
tubular member 170 which is provided with superior end 171,
inferior end 172 and a cylindrical or continuous wall extending
between the superior and inferior ends 171, 172 of the graft 55. A
midsection of the tubular member of the graft 55 is crimped to
resist kinking. Although a standard size crimp may be used, it is
preferred to make the crimps radially deeper and less numerous than
produced from standard crimping techniques. Having a sparsely
crimped profile also reduces the elongation properties of the graft
55. Moreover, a sparsely crimped graft 55 is easier to pack into
the capsule jacket than a standard crimped graft. The low bulk and
low elongation of the crimped graft further allows that the graft
55 may be packed into a smaller diameter capsule jacket.
Additionally, the low crimp elongation factor allows for a higher
degree of placement accuracy.
[0089] The crimps of the thoracic graft 55 may have a configuration
approximating a square wave wherein the raised portion has an
approximate width of 1.5 millimeters and the valley has an
approximate width of 0.7 millimeters. The resulting crimp pitch is
then preferably 2.2 millimeters. Further, the crimped graft 55 of
the present invention is configured with crimps having raised
portions that are preferably approximately 1.2 millimeters deep. So
configured, the graft 55 will maintain its high flexibility even
under arterial pressures of over one hundred mm Hg within the
corporeal lumen and the crimps will function to resist kinking.
Also, by being so configured, radiopaque markers may be sewn within
the selected valleys.
[0090] The tubular member may have a length in the range of 7 to 15
centimeters. The tubular member may have a diameter of 30 to 40 mm.
The continuous wall can be woven of any surgical implantable
material such as polyethylene terephthalate (PET or polyester), but
can be made of other materials such as PTFE. It is contemplated
that the wall thickness be approximately 0.005 to 0.009 inches
(0.127 to 0.229 mm), thinner than most conventional woven grafts.
In order to prevent unraveling of the woven material at the ends,
the ends can be melted with heat to provide a small melted bead of
material on each end.
[0091] As shown in FIG. 21, a segment of polyester yarn 199 or
similar material is used to produce a thrombogenic surface to
improve blood clotting along the inferior and superior ends of the
main tubular member 170. The filaments of the yarn segment are
teased apart to increase the embolization area. The yarn segment is
sutured to the wall 173 of the graft between one or more of the
vees 177 of the superior and inferior attachment systems 175, 176.
Other modifications may be made as to the location of the fuzzy
yarns to produce a similar result. Likewise, the graft may be made
of velour or terry to similarly occlude blood flow around the
outside of the ends of the graft adjacent the attachment system and
to enhance adhesion of the graft to the aorta.
[0092] Referring to FIG. 21, an expandable attachment system 175 is
secured adjacent the superior end 171 of the tubular member 170.
Similarly, an expandable attachment system 176 is secured adjacent
the tubular member's inferior end 172. Each attachment system
serves to yieldably urge the tubular member from a first compressed
or collapsed position to a second expanded position and provides a
fluid tight seal between the graft 55 and the corporeal lumen wall.
Each attachment system is formed of a plurality of vees 177 with
the outer apices 178 and inner apices 179 of the vees being formed
with helical torsion springs 180 to yieldably urge the long legs
and short legs of each of the vees outwardly at a direction
approximately at right angles to the plane in which each of the
vees lie.
[0093] As shown in more detail in FIGS. 23 and 24, the superior and
inferior attachment systems 175, 176 are comprised of a single
piece of wire which is formed to provide the vees 177 and also to
define the helical torsion springs 180 between the legs 181 and
182. The two ends of the single piece of wire can be welded
together in one of the legs to provide a continuous spring-like
attachment system and is approximately 30 mm long. In the
construction shown in FIGS. 23 and 24, it can be seen that the
attachment systems have apices lying in four longitudinally
spaced-apart parallel planes which are spaced with respect to the
longitudinal axis of the tubular member 170. The apices lying in
each plane are staggered to provide for the minimum profile when
the attachment systems are placed in its collapsed condition.
[0094] The superior and inferior attachment systems 175 and 176 are
secured to the superior and inferior ends 171 and 172,
respectively, of the tubular member 170 by suitable means such as a
polyester suture material 190. In an alternate embodiment, however,
it is further contemplated that the center section of the graft be
supported by one or more self-expanding attachment systems stacked
end to end. (See FIG. 25). As shown in FIG. 21, the suture material
is used for sewing the attachment systems onto the wall 173 of the
tubular member. The suture material runs along each of the legs or
struts 181 and 182 and through apices 178 and 179 to firmly secure
each leg to the graft and to keep outer edge of the graft 55 from
sliding medially along the attachment system. The inferior
attachment system 176 may be attached to the inferior end 172 of
the graft 55 in a similar manner. The furthest extending apices
protrude approximately 9 mm beyond the ends of the graft and it is
contemplated that the portion of the attachment system affixed to
the graft extend approximately 25 mm from the ends of the graft
toward its center. In a presently preferred embodiment, the
attachment systems 175,176 may be attached to the graft 55 so that
the bottom of the inner apices 179 are positioned adjacent the ends
171,172 of the graft 55. By so positioning the attachment systems
175,176, the fluid tight seal between the graft 55 and vessel wall
may be enhanced.
[0095] As shown in FIGS. 22-24, wall engaging members 195 are
preferably secured to near the center of the legs 181, 182 by
suitable means such as welding. The wall engaging members are
secured near the center of the legs 181, 182 because the least
amount of stress exists at the center of the legs 181, 182.
Consequently, the fatigue life of the weld or other securing means
is optimized. The wall engaging members are configured to extend
beyond the apices 178,179 approximately 2 mm and have a diameter
ranging from 0.015 to 0.025 inches and a length from 2 to 5
millimeters. The wall engaging members are preferably sharpened to
provide conical tips, and should have a length which is sufficient
for the tip to penetrate into and perhaps through the corporeal
lumen wall. There may be eight wall engaging members 195 per
attachment system, one extending beyond each inner and outer apex
178, 179, or there may be four wall engaging members 195 per
attachment system, wherein a wall engaging member extends beyond
each outer apex 178. It is also contemplated that the hook portion
of the wall engaging members, instead of being straight, be curved
radially outward to facilitate insertion into the wall of the lumen
being repaired (See FIG. 26). Further, the wall engaging members
may be affixed to a strut so that the hook portion is substantially
perpendicular to the plane in which the apex resides (FIGS. 23
& 24) or the hook may be routed over the apex, having its end
curved radially outward so as to keep a low radial profile (FIGS.
27 & 28).
[0096] The superior and inferior attachment systems 175, 176 and
the wall engaging members 195 secured thereto are formed of a
corrosion resistant material which has good spring and fatigue
characteristics. One such material found to be particularly
satisfactory is "ELGILOY" which is a cobalt-chromium-nickel alloy
manufactured and sold by Elgiloy of Elgin, Ill. The wire can have a
diameter ranging from 0.016 to 0.020 inches. For example, 0.020
inch diameter wire for the frame and wall engaging members may be
used in the larger grafts of 36 to 40 millimeters diameter.
[0097] It has been found that the spring force created by the
helical torsion springs 180 at the apices 178 and 179 is largely
determined by the diameter of the wire. The greater the diameter of
the wire, the greater the spring force applied to the legs 181 and
182 of the vees. Also, the longer the distances are between the
apices, the smaller the spring force that is applied to the legs.
It therefore has been desirable to provide a spacing between the
outer extremities of the legs of approximately thirty millimeters,
although smaller or larger distances may be utilized.
[0098] To facilitate securing the graft 55 in the corporeal lumen,
the wall engaging members 195 of the superior attachment system 175
and inferior attachment system 176 may be angled with respect to
the longitudinal axis of the tubular member 170. The wall engaging
members face outwardly from the tubular member to facilitate
holding the graft in place (See FIGS. 21-24). Preferably, the wall
engaging members on the superior attachment means are inclined from
the longitudinal axis and toward the inferior end of the graft 172
by 60.degree. to 80.degree. from radial. Likewise, the wall
engaging members of the inferior attachment system may be inclined
towards the superior end of the graft 175 by 60.degree. to
80.degree. from radial. By angling the wall engaging members so
that they resist the force of the blood flow, the implanted wall
engaging members oppose migration of the graft.
[0099] The helical torsion springs 180 placed at the apices 178 and
179 serve to facilitate compression of the graft 55 to place the
superior and inferior attachment systems 175 and 176 within the
capsule assemblies 90 and 130, as hereinafter described. The
compression of the graft may be accomplished by deformation of the
helical torsion springs to just beyond their elastic limit, thereby
having a small component within the plastic range. Placing the
apices in different planes and staggering or offsetting the wall
engaging members 195 and 196 significantly reduces the minimum
compressed size of the attachment systems. Having the apices in
different planes also helps to prevent the wall engaging members
from becoming entangled with each other or with the apices. The
natural spring forces of the helical torsion springs serves to
expand the graft to its expanded position as soon as the attachment
system is released. Significantly, the spring forces of the
attachment system of the graft 55 are such that the graft is
securely attached within the lumen without the aid of a balloon
catheter.
[0100] The graft 55 includes releasable ties 205, 207 attached to
its exterior near the superior and inferior ends 171, 172 of the
graft 55 respectively. The releasable ties 205, 207 cooperate with
the release wire 57 of the delivery catheter 50 to load the
attachment systems 175, 176 of the graft 55 within the inferior and
superior capsules assemblies 90, 130 and to subsequently emplace
the graft 55 within a corporeal lumen. As shown in FIG. 22, each
releasable tie 205, 207 consists of a single thread that is
attached at its midsection to the graft 55 so that a majority of
the ties 205, 207 reside exterior to the graft 55 and configured
into two loops. The loops are wrapped around the graft 55 and are
placed into engagement with the release wire 57 by threading the
release wire through each of the loops respectively. In the
alternative, the ties 205, 207 can be looped around the release
wire 57. Thereafter, the ends of the ties 205, 207 are pulled tight
to collapse the attachment systems 175, 176 and are then stitched
to the graft 55 and knotted.
[0101] It is to be noted that the ties 205, 207 can be threaded
through the portions of the sutures which reside on the exterior of
the graft and which secure the attachment systems to the graft 55.
By doing so, when the release wire 57 is removed from engagement
with the ties 205, 207, they are conveniently restrained from
interfering with the expansion of the attachment systems. Further,
due to the relative small size of the loops formed in the ties 205,
207, upon expansion of the attachment systems, they are removed
from contacting the attachment systems. Moreover, by so configuring
the ties 205, 207, they are kept out of the way of blood flow and
are, therefore, made unavailable for occluding the vessel or
causing the formation of unwanted blood clots. The ties 205, 207
may be made from braided polyester or nylon suture or any other
material having similar properties.
[0102] In order to engage the releasable ties 205, 207, the release
wire 57 is configured to pass through the walls of the graft 55.
Since the graft 55 is contemplated to be woven, it comprises warp
and weft yarns which are separated to allow passage of the release
wire 57 through the walls of the graft 55. A superior passageway
209 is provided by separating warp and weft yarns located near the
superior end 171 of the graft 55. Similarly, an inferior passageway
211 is provided by separating warp and weft yarns located near the
inferior end 172 of the graft 55. In a presently preferred
embodiment, each of the passageways 209, 211 consist of two sets of
closely spaced-apart warp and weft yarns which are individually
separated to allow passage of the release wire 57 through the walls
of the graft 55, wherein one of the two sets of warp and weft yarns
serves as an exit and the other as an entrance. In an alternate
embodiment, each of the passageways 209, 211 consist of one set of
warp and weft yarns that is separated to thereby provide both an
exit and entrance for the release wire 57 through the graft
walls.
[0103] In other embodiments, the releasable ties 205, 207 maybe
passed through the graft 55 in order to be placed into engagement
with the release wire 57. Further, the releasable ties 205, 207 may
be configured so that eyes which are adapted to receive the release
wire are knotted into each end of the ties. Additionally, it is
also contemplated that, rather than passing the release wire 57
through each loop of each releasable tie 205, 207, the release wire
57 may be passed through only one loop of each releasable tie and
the other loop of each releasable tie is placed around the first
loop of the releasable tie receiving the release wire in order to
provide a cooperating system for compressing the attachment systems
175, 176.
[0104] The graft 55 preferably contains radiopaque markers means
for locating the graft 55 and for detecting any twisting of the
graft 55 during deployment. The radiopaque marker means takes the
form radiopaque markers 197 affixed along the crimped midsection of
the graft and within the valleys comprising the crimped portion.
The radiopaque markers are made of a suitable material such as a
platinum tungsten alloy wire of a suitable diameter such as 0.004
inches (0.102 mm) which is wound into a spring coil having a
diameter of 0.4 inches (1.0 mm). The radiopaque markers are secured
to the tubular member 170 by sutures 199, using the same material
to secure the attachment systems to the graft.
[0105] Referring also to FIG. 21, the radiopaque markers 197 have a
length of approximately 3 millimeters. By placing markers along the
tubular member, it is possible to ascertain the position of the
graft 55 and to determine whether the graft 55 has twisted between
its superior and inferior ends 171, 172. Under fluoroscopy, the
markers will be exhibited as a relatively straight lines for an
untwisted graft, wherein a twisted graft will be revealed by a
non-parallel pattern of markers. By placing the markers at equal
increments apart, it is possible to use fluoroscopy to ascertain
longitudinal compression or tension on the graft.
[0106] The sizing of the graft 55 may be performed on a
patient-by-patient basis, or a series of sizes may be manufactured
to adapt to most patient needs. For the repair of a thoracic
aneurysm, the length of the graft 55 is selected so to span
approximately one centimeter superior and one centimeter inferior
of the aneurysm, wherein the wall engaging members 195 and 196 of
the graft can seat within normal tissue of the vessel on both sides
of the aneurysm. Thus, the graft should be about two centimeters
longer than the aneurysm being repaired. During the pre-implant
fluoroscopy procedure, a conventional pigtail angiography catheter
is used to determine the locations of proximal arteries to ensure
they will not be covered by the implanted graft. Similarly, the
diameter of the tubular member 170 is selected by measuring the
corporeal lumen which will receive the graft by conventional
radiographic techniques and then selecting a tubular member having
a diameter one millimeter larger than that measured. For specific
applications, one or more pleats 198 may be sewn into the walls of
the grafts so as to provide a more suitable emplacement within a
lumen having a narrow portion (See FIGS. 29-32). The suture
material 190 used for affixing the attachment systems to the graft
may be used for providing the graft with pleats.
[0107] FIG. 12 depicts the distal end of the delivery catheter 50
assembled for deployment. The graft 55 is disposed within the
capsule jacket assembly 53. The superior attachment system 175 is
removably retained within the superior capsule 93. Likewise,
inferior attachment system 176 is removably retained within the
proximal capsule 132. The superior cap 92, nose cone 94 and
superior capsule 93 are in the retracted or proximal position
adjacent to the conical-shaped knob 100. Similarly, control wire 91
is locked (not shown) via control knob 113 in its retracted or
proximal position. During initial deployment, the outer shaft
member 131 is in its most distal position in relation to inner
catheter assembly 51 and is locked in place by the locking ring on
the Touhy Borst adapter 147 (not shown).
[0108] During initial deployment, the conical-shaped knob 100 is
positioned just proximal to the superior cap 92 and is disposed
within the superior capsule 93. Moreover, as depicted in FIG. 12,
the releasable ties 205, 207 are wrapped around the graft 55 and
are placed into engagement with the release wire 57 to thereby
place the inferior and superior attachment systems 176, 175 in a
collapsed configuration.
[0109] Further, the release wire 57 is configured so that it is
disposed within the release wire lumen 64 of the inner shaft 61.
The release wire 57 first exits the inner shaft 61 through the
inferior release wire notch 102 and then passes through the
inferior passageway 211 of the graft 55 and through the loops of
the inferior releasable tie 207 (see FIGS. 33 and 34). From there,
the release wire 57 passes back through the inferior passageway 211
and inferior release wire notch 102 of the inner shaft 61 and back
into the release wire lumen 64. The release wire 57 then passes
through the release wire lumen 64 until it reaches the second
release wire notch 104 formed in the inner shaft 61. The release
wire 57 passes through the second notch 104 and through the
superior passageway 209 of the graft 55 and through the loops
formed in the superior releasable tie 205. Finally, the release
wire 57 reenters the inner shaft 61 by again passing through the
superior passageway 209 and the second release wire notch 104 and
advances distally within the release wire lumen 64. By so
configuring the release wire 57, the attachment systems 175, 176
are locked to the inner shaft 61 both radially and axially.
[0110] In another embodiment of the delivery catheter 50, it is
contemplated to include a second release wire 217 (see FIG. 35). In
this embodiment, each release wire is configured to cooperate with
one of the releasable ties 205, 207. For instance, the first
release wire 57 may be configured to cooperate with the releasable
tie 207 attached to the inferior end 172 of the graft and the
second release wire 217 may be configured to cooperate with the
releasable tie 205 attached to the superior end 171 of the graft
55. Also, in the two release wire system, the first release wire 57
is configured to pass through the inferior notch 102 and the second
release wire 217 is configured to pass through the superior or
second notch 104. Further, the two release wires may share the
release wire lumen 64 or a second release wire lumen may be formed
in the inner shaft 69.
[0111] Referring again to FIG. 12, it shows the attachment of the
anti-elongation wire 59 to the inner shaft 61. In one presently
preferred embodiment, the anti-elongation wire 59 is advanced
through the anti-elongation wire lumen 66 until it reaches a
longitudinal position along the inner shaft 61 near where the graft
55 is loaded in a delivery catheter 50 assembled for deployment. At
this longitudinal position, the anti-elongation wire 59 exits the
inner shaft 61 through an anti-elongation wire notch 213 and is
affixed to the inner shaft 61 by way of an anti-elongation band
215. Formed into the exterior of the inner shaft 61 and positioned
on either side of the band 215 may be low profile bumps (not shown)
which facilitate retaining the band 215 in place on the inner shaft
61. The anti-elongation wire 59 is inserted through a gap or hole
formed in the band 215 and tied into a knot to thereby prevent
proximal movement of the anti-elongation wire relative to the inner
shaft 61. The anti-elongation wire 59 is similarly affixed to the
inner shaft 61 at its proximal end in that it exits the inner shaft
61, passes through another band flanked by low profile bumps (not
shown) and is tied in a knot to prevent distal movement of the
anti-elongation wire relative to the inner shaft 61. In another
presently preferred embodiment, the anti-elongation wire 59 lies
outside the inner shaft 61 but is similarly attached to the inner
shaft 61 to prevent elongation thereof.
[0112] Further, as shown in FIG. 12, the capsule jacket assembly 53
is positioned such that the distal end of the capsule jacket main
jacket 160 overlaps at least a portion of the distal capsule 93.
During deployment, capsule jacket locking connector 162 (not shown)
secures the main jacket in place. Thus, when any movement or force
is applied to the handle assembly 110, the entire apparatus 50
moves as a single unit.
[0113] By way of example, the following describes a method of
repair of an aortic aneurysm using the method comprising the
present invention for intraluminal placement of a graft in an
aorta. First, a patient is prepared in a conventional manner by use
of a guide wire 56, a dilator and sheath (not shown) to open the
iliac artery or abdominal aorta or vessel of the patient. The
distal end of the delivery catheter 50 is then inserted into the
sheath, which has previously been placed in the vessel. In the
preferred embodiment of the present invention, inner shaft lumen 63
is provided for receiving the guide wire 56. However, the following
procedure may also be used when the guiding member is constructed
as part of the inner catheter assembly 51.
[0114] As shown in FIG. 36, the guide wire 56 is introduced by the
physician into the femoral artery and advanced to the desired
location in the aorta 200 and adjacent to the diseased or damaged
portion of the vessel 201. The inner catheter assembly 51, the
inferior capsule catheter 52, the capsule jacket assembly 53, the
control wire assembly 54 and the releasing system are all
configured for deployment of the graft as shown in FIGS. 1 and 12.
Thus, the assemblies are advanced by the physician as a single unit
over the guide wire. The physician uses the handle assembly 110 and
the proximal end of the inner shaft member 70 to guide the distal
end of the assemblies over the guide wire.
[0115] Next, the locking connector 162 of the capsule jacket
assembly 53 is loosened to allow movement of the capsule jacket
main jacket 160 (See FIG. 1). It is to be noted that the capsule
jacket main jacket 160 may be withdrawn prior or subsequent to
advancing the graft 55 and delivery catheter 50 to the repair site.
While using one hand to firmly grasp the inferior capsule catheter
52 and hold it stationary, the physician grasps the jacket adapter
164 with the other hand and gently pulls the jacket adapter
proximally towards the capsule catheter wye adapter 145, as shown
in FIG. 37. The capsule jacket assembly 53 is moved to fully expose
graft 55 and the inferior and superior capsule assemblies 90, 130.
At this time, the releasing system retains the graft 55 within the
inferior and superior capsules assemblies 90, 130. The release wire
57 functions to limit relative movement of the ends of the graft 55
and the capsules by engaging the releasable ties 205, 207 wrapped
around the graft 55 (see FIG. 12). The locking connector 162 is
then tightened to hold the capsule jacket assembly 53 in place.
[0116] The control knob 113 is then rotated to cause relative
movement between the superior capsule assembly 90 and the inner
catheter assembly 51 to expose the superior attachment system 175
(see FIGS. 1, 12 & 38). Rotating the control knob 113 causes
the retaining rack 120 to move the control wire 91 in a distal
direction. Since the superior cap 92 and superior capsule 93 are
secured to the control wire 91, they move in corresponding
relationship with the rotation of the control knob 113. As the
superior capsule assembly 90 is moved from engagement with the
superior attachment system 175, the conical-shaped knob is exposed,
creating a smooth profile at the proximal end of the superior
capsule to thereby facilitate removal of the superior end of the
delivery catheter from within the implanted graft. At this point,
the anti-elongation wire 59 functions to prevent the inner shaft 61
from stretching. As the control knob 113 is turned, the control
wire 91 and superior capsule assembly 90 advance within the
vasculature of the patient. However, if the inner shaft 61 is
easily stretched and if the distal end of the catheter is bent
relative to the superior capsule assembly 90, the force advancing
the capsule assembly 90 may stretch the inner shaft 61 rather than
slide the capsule assembly 90 distally on the inner shaft 61. The
anti-elongation wire prevents this.
[0117] As shown in FIG. 39, with the handle assembly 110 held
firmly in place, the inferior capsule catheter 52 is next moved
proximally, which results in the inferior attachment system 176 to
be removed from the inferior capsule assembly 130 (see also FIGS. 1
& 12). Once the inferior attachment system 176 is free of the
inferior capsule assembly 130, the release wire 57 can be withdrawn
from engagement with the superior and inferior ties 205, 207 to
thereby allow the attachment systems 175, 176 to spring open and
engage the walls of the lumen (see FIGS. 40, 41). The ties 205, 207
remain attached to the exterior of the graft and out of blood flow.
The force with which the attachment systems 175, 176 spring open,
in conjunction with the forces applied by the blood present in the
aorta against the interior of the graft 55, operates to seat the
attachment systems of the graft 55 within the aorta.
[0118] Although the method of deployment described involved
removing each attachment system from the capsules prior to
withdrawing the release wire 57, it is to be understood that, for
example, the superior attachment system 175 can be removed from the
superior capsule assembly 90 and the release wire 57 withdrawn to
allow the superior attachment system 175 to engage the walls of the
lumen prior to doing the same with the inferior attachment system
176 so that the inferior attachment system 176 engages the lumen.
Further, it is important to avoid placing the graft 55 in excessive
longitudial tension, as such a condition may cause the graft 55 to
close should it be deployed in a curved position of a lumen. To
avoid placing the graft 55 in such a condition, the end of the
graft 55 which is yet to be deployed can be moved toward the end of
the graft 55 that has been deployed.
[0119] When the graft 55 is seated within the aorta, the wall
engaging members 195 of the superior attachment system 175 point
proximally and with the direction of blood flow, whereas the wall
engaging members 195 of the inferior attachment system 176 point
distally and against the direction of blood flow. By so orienting
the wall engaging members 195, the graft 55 is prevented from
migrating downstream or upstream within the aorta. The wall
engaging members 195 of the superior attachment system 175 prevent
the graft 55 from migrating downstream in response to forces
applied to the graft 55 by the direction of blood flow. Similarly,
the wall engaging members 195 of the inferior attachment system 176
prevent the graft from migrating upstream in response to forces
applied by the blood within the aorta.
[0120] A number of the steps of the previously described method for
placing the graft 55 within a vessel lumen may be reordered so that
the inferior end 172 of the graft 55 may be attached within the
lumen prior to attaching the superior end 171 of the graft 55
within the lumen. This alternate procedure may be preferred when
repairing a thoracic aortic aneurysm because of the high blood flow
and flow rate in the thoracic region of the aorta. By attaching the
inferior end of the graft first, the drag on the partially
implanted graft may be minimized, thereby avoiding the potential
problem of the graft 55 being forced from engagement with the
vessel lumen.
[0121] In order to attach the inferior end 172 of the graft 55
within the lumen prior to attaching the superior end 171 within the
lumen, the two release wire system (see FIG. 35) may be employed.
By withdrawing the first release wire 57 prior to withdrawing the
second release wire 217, the inferior attachment system 176 can be
permitted to engage the walls of the lumen before the superior
attachment system 175 does so, to thereby attach the inferior end
172 of the graft 55 within the lumen before the superior end 171 is
attached within the lumen. The second release wire 217 can then be
withdrawn to attach the superior end 171 of the graft 55 within the
lumen. This dual release wire system can also be used to attach the
superior end 172 of the graft 55 within the lumen first.
[0122] As a final step in any of the methods employed, the delivery
catheter is removed from the patient (not shown). The superior
capsule assembly 90 and distal end of the inner shaft 61 are moved
proximal relative to the graft 55 by first loosening the locking
ring 147 (See FIG. 1). Then, while holding the inferior capsule
catheter 52 in place by grasping the wye adapter 145 with one hand,
the inner catheter assembly 51 is moved proximally by gently
pulling the handle assembly 110 with the other hand. The proximal
end of the superior capsule 93 may be mated with the inferior
capsule for smooth transition.
[0123] Finally, the capsule jacket locking connector 162 is
loosened. While holding the capsule jacket adapter 164 in place,
the inner catheter assembly and inferior capsule catheter 51 and 52
are moved proximally and in unison by gently pulling the wye 145 of
the inferior capsule catheter. The catheters are moved until the
distal end of the main jacket 163 covers the superior capsule 93 or
until the inferior capsule adapter housing 134 mates with the
flared transition of the capsule jacket, thereby creating a smooth
transition along the entire length of the delivery catheter 50.
Thereafter, the inner catheter assembly 57, inferior capsule
catheter 52, capsule jacket assembly 53 and control wire assembly
54 are removed from the aorta through the incision. The graft 55
and attachment systems 175 and 176 remain secured to the vessel
wall 202, thereby sealing the aneurysm 201 from blood flow.
[0124] The entire procedure described herein can be observed under
fluoroscopy. The relative positioning of the graft 55 and the
delivery catheter 50 can be readily ascertained by the radiopaque
attachment systems 175 and 176, radiopaque markers 197 provided on
the graft, and the radiopaque marker 87 on the inner shaft 61 (See
FIG. 5). If any twisting of the graft has occurred between
placement of the superior attachment system and the inferior
attachment system, then the twisting can be readily ascertained by
observing the series of markers 197. Adjustments to eliminate any
twisting which may have occurred can be made before exposing the
graft's second extremity 172 by rotation of the catheter 52. Any
excessive graft tension or compression can be ascertained by
observing the radiopaque markers 197 under fluoroscopy. Adjustments
to graft tension can be made before exposing the second extremity
of the graft by applying tension on the capsule catheter assembly
52.
[0125] Post implant fluoroscopy procedures can be utilized to
confirm the proper implantation of the device by the use of a
conventional angiographic pigtail catheter or by injecting
radiopaque contrast into the guide wire lumen of the balloon
catheter shaft. Thereafter the jacket can be removed from the
patient and the incisions closed with conventional suturing
techniques. Tissues should begin to grow into the graft within two
to four weeks. This establishes a complete repair of the aneurysm
which had occurred.
[0126] While several particular forms of the invention have been
illustrated and described, it will be apparent that various
modifications can be made without departing from the spirit and
scope of the invention. For example, references to materials of
construction and specific dimensions are also not intended to be
limiting in any manner and other materials and dimensions could be
substituted and remain within the spirit and scope of the
invention. Accordingly, it is not intended that the invention be
limited, except as by the appended claims.
* * * * *