U.S. patent application number 10/307226 was filed with the patent office on 2006-03-30 for intraluminal prosthesis attachment systems and methods.
This patent application is currently assigned to APTUS ENDOSYSTEMS, INC.. Invention is credited to Lee Bolduc, Alan L. Kaganov.
Application Number | 20060069422 10/307226 |
Document ID | / |
Family ID | 36128600 |
Filed Date | 2006-03-30 |
United States Patent
Application |
20060069422 |
Kind Code |
A9 |
Bolduc; Lee ; et
al. |
March 30, 2006 |
Intraluminal prosthesis attachment systems and methods
Abstract
Systems and method implant prostheses in the body. The systems
and methods provide permanent attachment of the prosthesis in the
body. The prosthesis can comprise, e.g., an endovascular graft,
which can be deployed without damaging the native blood vessel in
either an arterial or a venous system. The endovascular graft can
comprise, e.g., a radially expanding vascular stent and/or a
stent-graft. The graft can be placed in the vasculature, e.g., to
exclude or bridge an aneurysm, for example, an abdominal aortic
aneurysms. The graft desirably adapts to changes in aneurysm
morphology and repairs the endovascular aneurysm. The fastening
systems and methods can be deployed through the vasculature and
manipulated from outside the body, to deliver a fastener to attach
the graft to the vessel wall.
Inventors: |
Bolduc; Lee; (Sunnyvale,
CA) ; Kaganov; Alan L.; (Portla Valley, CA) |
Correspondence
Address: |
RYAN KROMHOLZ & MANION, S.C.
Post Office Box 26618
MILWAUKEE
WI
53226
US
|
Assignee: |
APTUS ENDOSYSTEMS, INC.
|
Prior
Publication: |
|
Document Identifier |
Publication Date |
|
US 20040093057 A1 |
May 13, 2004 |
|
|
Family ID: |
36128600 |
Appl. No.: |
10/307226 |
Filed: |
November 29, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10271334 |
Oct 15, 2002 |
6960217 |
|
|
10307226 |
Nov 29, 2002 |
|
|
|
60333937 |
Nov 28, 2001 |
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Current U.S.
Class: |
623/1.11 |
Current CPC
Class: |
A61F 2/95 20130101; A61F
2/07 20130101; A61F 2/89 20130101; A61F 2002/075 20130101; A61B
2017/0649 20130101; A61F 2002/065 20130101; A61B 17/068 20130101;
A61F 2/064 20130101; A61B 17/064 20130101; A61B 2017/0647
20130101 |
Class at
Publication: |
623/001.11 |
International
Class: |
A61F 2/06 20060101
A61F002/06 |
Claims
1. A fastener applier for a prosthesis comprising: a drive
mechanism sized and configured to be releasably coupled to the
fastener to deploy the fastener into the prosthesis, and an
actuator for the drive mechanism including a sensing mechanism that
enables operation of the drive mechanism in response to a force
sensed at or near the fastener.
2. A fastener applier according to claim 1 wherein the sensing
mechanism disables operation of the drive mechanism when force
sensed is less than a predetermined magnitude.
3. A fastener applier according to claim 1 wherein the sensing
mechanism includes a switch assembly that is actuated in response
to force sensed at or near the fastener.
4. A fastener applier for a prosthesis comprising: a drive
mechanism sized and configured to be releasably coupled to the
fastener to deploy the fastener into the prosthesis, and an
actuator for the drive mechanism including a sensing mechanism that
enables operation of the drive mechanism in response to contact
sensed with a surface at or near the fastener.
5. A fastener applier according to claim 4 wherein the sensing
mechanism disables operation of the drive mechanism in the absence
of contact sensed.
6. A fastener applier according to claim 4 wherein the sensing
mechanism includes a switch assembly that is actuated in response
to contact sensed at or near the fastener.
7. A fastener applier according to claim 1 or 4 wherein the drive
mechanism includes a carrier for the fastener.
8. A fastener applier according to claim 7 wherein the carrier
receives a single fastener at a time.
9. A fastener applier according to claim 1 or 4 wherein the drive
mechanism is magnetically coupled to the fastener.
10. A fastener applier according to claim 9 wherein the drive
mechanism is magnetically coupled to a single fastener at a
time.
11. A fastener applier according to claim 1 or 4 wherein the drive
mechanism is mechanically coupled to the fastener.
12. A fastener applier according to claim 11 wherein the drive
mechanism is mechanically coupled to a single fastener at a
time.
13. A fastener applier according to claim 1 or 4 wherein the drive
mechanism rotates the fastener for deployment.
14. A fastener applier according to claim 1 or 4 further including
a catheter body sized and configured for deployment in a targeted
body region, and wherein at least a portion of the drive mechanism
is carried by the catheter body.
15. A fastener applier according to claim 14 wherein the catheter
body includes a distal end, and wherein the sensing mechanism
includes a component extending distally beyond the distal end of
the catheter body.
16. A fastener applier according to claim 15 wherein the component
includes a carrier for the fastener.
17. A fastener applier according to claim 15 wherein the component
includes a force sensing probe.
18. A fastener applier according to claim 1 or 4 further including
a catheter body sized and configured for intraluminal passage, and
wherein at least a portion of the drive mechanism is carried by the
catheter body for deployment in a targeted endovascular region.
19. A fastener applier according to claim 18 wherein the catheter
body includes a distal end, and wherein the sensing mechanism
includes a component extending distally beyond the distal end of
the catheter body.
20. A fastener applier according to claim 19 wherein the component
includes a carrier for the fastener.
21. A fastener applier according to claim 19 wherein the component
includes a sensing probe.
22. A fastener sized and configured for singular deployment in
tissue comprising a fastener body having a distal end for
penetrating tissue in response to a force and a proximal end for
releasably coupling the fastener body to a force applier, and a
stop structure associated with the proximal end to prevent
over-penetration of the fastener body into tissue.
23. A fastener according to claim 22 wherein the fastener body
comprises a helical coil having an interior diameter, and wherein
the stop structure comprises a leg of the coil that extends
substantially across the entire interior diameter.
24. A fastener according to claim 23 wherein the leg mechanically
couples the fastener body to the force applier.
25. A fastener according to claim 22 wherein the fastener body
comprises a helical coil having an interior diameter, and wherein
the stop structure comprises a cap that extends substantially
across the entire interior diameter.
26. A fastener according to claim 25 wherein the cap includes a
fitting to engage the force applier.
27. A fastener according to claim 25 wherein the cap includes a
material that is magnetized.
28. A fastener according to claim 25 wherein the cap includes a
material that is attracted to a magnetized material.
29. A fastener according to claim 22 wherein the stop structure
couples the fastener body to the force applier.
30. A fastener according to claim 29 wherein the stop structure
includes a material that is magnetized.
31. A fastener according to claim 29 wherein the stop structure
includes a material that is attracted to a magnetized material.
32. A fastener according to claim 29 wherein the stop structure
mechanically couples the fastener body to the force applier.
33. A fastener according to claim 22 wherein the fastener body
comprises a helical coil.
34. A system for applying a fastener to a prosthesis within a body
comprising a fastener comprising a body having a distal end for
penetrating tissue in response to a force and proximal end, a drive
mechanism sized and configured to be releasably coupled to the
proximal end of the fastener body to apply force, and an actuator
for the drive mechanism including a sensing mechanism that enables
operation of the drive mechanism in response to at least one of
force sensed at or near the distal end of the fastener body, or
(ii) contact sensed with a surface at or near the distal end of the
fastener body.
35. A system according to claim 34 wherein the fastener includes a
stop structure associated with the proximal end to prevent
over-penetration of the fastener body into tissue.
36. A system according to claim 34 wherein the drive mechanism is
sized and configured to be releasably coupled to a single fastener
at a time.
37. A system according to claim 34 further including a catheter
body sized and configured for deployment in a targeted body region,
and wherein at least a portion of the drive mechanism is carried by
the catheter body.
38. A system according to claim 34 further including a catheter
body sized and configured for intraluminal passage, and wherein at
least a portion of the drive mechanism is carried by the catheter
body for deployment in a targeted endovascular region.
39. A system for applying a fastener to a prosthesis within a body
comprising a fastener comprising a body having a distal end for
penetrating tissue in response to a force and proximal end that
includes a stop structure to prevent over-penetration of the
fastener body into tissue, and a drive mechanism sized and
configured to be releasably coupled to the stop structure to apply
force.
40. A system according to claim 39 wherein the drive mechanism is
sized and configured to be releasably coupled to a single fastener
at a time.
41. A system according to claim 39 further including a catheter
body sized and configured for deployment in a targeted body region,
and wherein at least a portion of the drive mechanism is carried by
the catheter body.
42. A system according to claim 39 further including a catheter
body sized and configured for intraluminal passage, and wherein at
least a portion of the drive mechanism is carried by the catheter
body for deployment in a targeted endovascular region.
43. A prosthesis comprising a prosthesis body, a fastener assembly
integrally carried by the prosthesis body, the assembly including
at least one fastener deployable into tissue in response to force
applied by a force applier, and a tracking wire coupled to the
fastener to guide the force applier into operative contact with the
fastener.
44. A prosthesis comprising a prosthesis body, and a fastener
assembly integrally carried by the prosthesis body, the assembly
including at least one fastener deployable into tissue in response
to non-rotational force applied by a force applier.
45. A prosthesis according to claim 44 further including a tracking
wire coupled to the fastener to guide the force applier into
operative contact with the fastener.
46. A fastener sized and configured for singular deployment in
tissue comprising a fastener body having a distal end for
penetrating tissue in response to a force and proximal end for
releasably coupling the fastener body to a force applier, and a
tracking wire coupled to the proximal end to guide the force
applier into operative contact with the fastener.
Description
RELATED APPLICATION
[0001] This application claims the benefit of co-pending U.S.
patent application Ser. No. 10/271,334, filed Oct. 15, 2002. This
application also claims the benefit of co-pending U.S. Provisional
Application Serial No. 60/333,937 filed 28 Nov. 2001.
BACKGROUND OF THE INVENTION
[0002] The invention relates generally to the attachment of a
vascular prosthesis to a native vessel, and in particular, to a
method and system of devices for the repair of diseased and/or
damaged sections of a vessel.
[0003] The weakening of a vessel wall from damage or disease can
lead to vessel dilatation and the formation of an aneurysm. Left
untreated, an aneurysm can grow in size and may eventually
rupture.
[0004] For example, aneurysms of the aorta primarily occur in
abdominal region, usually in the infrarenal area between the renal
arteries and the aortic bifurcation. Aneurysms can also occur in
the thoracic region between the aortic arch and renal arteries. The
rupture of an aortic aneurysm results in massive hemorrhaging and
has a high rate of mortality.
[0005] Open surgical replacement of a diseased or damaged section
of vessel can eliminate the risk of vessel rupture. In this
procedure, the diseased or damaged section of vessel is removed and
a prosthetic graft, made either in a straight of bifurcated
configuration, is installed and then permanently attached and
sealed to the ends of the native vessel by suture. The prosthetic
grafts for these procedures are usually unsupported woven tubes and
are typically made from polyester, ePTFE or other suitable
materials. The grafts are longitudinally unsupported so they can
accommodate changes in the morphology of the aneurysm and native
vessel. However, these procedures require a large surgical incision
and have a high rate of morbidity and mortality. In addition, many
patients are unsuitable for this type of major surgery due to other
co-morbidities.
[0006] Endovascular aneurysm repair has been introduced to overcome
the problems associated with open surgical repair. The aneurysm is
bridged with a vascular prosthesis, which is placed intraluminally.
Typically these prosthetic grafts for aortic aneurysms are
delivered collapsed on a catheter through the femoral artery. These
grafts are usually designed with a fabric material attached to a
metallic scaffolding (stent) structure, which expands or is
expanded to contact the internal diameter of the vessel. Unlike
open surgical aneurysm repair, intraluminally deployed grafts are
not sutured to the native vessel, but rely on either barbs
extending from the stent, which penetrate into the native vessel
during deployment, or the radial expansion force of the stent
itself is utilized to hold the graft in position. These graft
attachment means do not provide the same level of attachment when
compared to suture and can damage the native vessel upon
deployment.
SUMMARY OF THE INVENTION
[0007] The invention provides systems and methods for implanting
prostheses in the body. The systems and methods provide permanent
attachment of the prosthesis in the body. The prosthesis can
comprise, e.g., an endovascular graft, which can be deployed
without damaging the native blood vessel in either an arterial or a
venous system. The endovascular graft can comprise, e.g., a
radially expanding vascular stent and/or a stent-graft. The graft
can be placed in the vasculature, e.g., to exclude or bridge an
aneurysm, for example, an abdominal aortic aneurysm. The graft
desirably adapts to changes in aneurysm morphology and repairs the
endovascular aneurysm. The fastening system and methods are
deployed through the vasculature and manipulated from outside the
body, to deliver a fastener to attach the graft to the vessel
wall.
[0008] One aspect of the invention provides a fastener applier for
a prosthesis. The applier comprises a drive mechanism sized and
configured to be releasably coupled to the fastener to deploy the
fastener into the prosthesis. The applier also includes an actuator
for the drive mechanism including a sensing mechanism that enables
operation of the drive mechanism in response to at least one of (i)
a force sensed at or near the fastener, and (ii) contact sensed
with a surface at or near the distal end of the fastener body.
[0009] Another aspect of the invention provides a fastener sized
and configured for deployment in tissue. The fastener includes a
fastener body having a distal end for penetrating tissue in
response to a force. The fastener body also has a proximal end for
releasably coupling the fastener body to a force applier. The
fastener includes a stop structure associated with the proximal end
to prevent over-penetration of the fastener body into tissue. In
one embodiment, the stop structure couples the fastener body to the
force applier, e.g., by a magnetic or mechanical coupling. On one
embodiment, the fastener body can comprise, e.g., a helical
coil.
[0010] Another aspect of the invention provides a fastener sized
and configured for deployment in tissue. The fastener comprises a
fastener body having a distal end for penetrating tissue in
response to a force. The fastener body also has a proximal end for
releasably coupling the fastener body to a force applier. A
tracking wire is coupled to the proximal end to guide the force
applier into operative contact with the fastener.
[0011] Another aspect of the invention provides a prosthesis
comprising a prosthesis body and a fastener assembly integrally
carried by the prosthesis body. The fastener assembly includes at
least one fastener deployable into tissue in response to force
applied by a force applier. A tracking wire is coupled to the
fastener to guide the force applier into operative contact with the
fastener.
[0012] Another aspect of the invention provides a prosthesis
comprising a prosthesis body and a fastener assembly integrally
carried by the prosthesis body. The assembly includes at least one
fastener deployable into tissue in response to non-rotational force
applied by a force applier.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The invention will be understood from the following detailed
description of preferred embodiments, taken in conjunction with the
accompanying drawings, wherein:
[0014] FIG. 1 is a perspective view of one embodiment of an
endovascular graft delivery device shown positioned within an
abdominal aortic aneurysm;
[0015] FIG. 2 is a perspective view of one embodiment the
deployment of an endovascular graft within the aneurysm of FIG.
1;
[0016] FIG. 3 is a perspective view of a fully deployed straight
endovascular graft of FIG. 2;
[0017] FIG. 4 is a perspective view of a fully deployed bifurcated
endovascular graft broken away to show an anchoring scaffold at one
end;
[0018] FIG. 5 is a perspective view similar to FIG. 5 showing an
alternative scaffold structure;
[0019] FIG. 6 is a perspective view showing one embodiment of a
device for directing the fastener applier;
[0020] FIG. 7 is a perspective view showing the device of FIG. 6
upon insertion within the deployed endovascular graft of FIG. 3
with both the graft and scaffolding broken away;
[0021] FIG. 8 is a perspective view of the device of FIG. 6 showing
activation of one embodiment of a stabilizing device attached to
the directing device;
[0022] FIG. 9 is a perspective view of the control assembly in FIG.
8 articulating the directing device of FIG. 6;
[0023] FIG. 10 is a perspective view of an alternative embodiment
of the stabilization device of FIG. 8;
[0024] FIG. 11 is a perspective view showing the activation of the
alternative stabilization device of FIG. 10;
[0025] FIG. 12 is a perspective view showing another embodiment of
the stabilization device of FIG. 8;
[0026] FIG. 13 is a perspective view showing activation of the
stabilization device of FIG. 12;
[0027] FIG. 14 is one embodiment of the fastener applier;
[0028] FIG. 14A is an enlarged view of the distal end of the
fastener applier shown in FIG. 14, showing the details of the
fastener drive mechanism;
[0029] FIG. 14B is a section view of the interior of the handle of
the fastener applier shown in FIG. 14;
[0030] FIG. 15 is a perspective view of the fastener applier of
FIG. 14 being positioned within directing device of FIG. 6;
[0031] FIG. 16 is an enlarged cross-sectional view of one
embodiment of the fastener applier of FIG. 14;
[0032] FIG. 17 is an enlarged cross-sectional view of the
attachment applier showing one embodiment of the proximal end of
the helical fastener and the drive mechanism;
[0033] FIG. 18 is a enlarged perspective view of one embodiment of
the helical fastener of FIG. 16;
[0034] FIG. 19 is an enlarged view of the attachment applier
showing one embodiment of the control assembly that activates the
fastener applier;
[0035] FIG. 20 is an enlarged view of the attachment applied
activated with a fastener implanted into the graft and vessel
wall;
[0036] FIG. 21 is an enlarged view of the completed attachment of
the proximal graft of FIG. 3 to the vessel wall with fasteners;
[0037] FIG. 22 is a perspective view of the graft of FIG. 4
completely attached to the vessel;
[0038] FIG. 23 is an enlarged section view of the drive mechanism
of the fastener applier shown in FIG. 14, showing a contact/force
sensing assembly that disables the applier in the absence of
desired contact between the fastener and a targeted tissue
region;
[0039] FIG. 24 is an enlarged section view of the drive mechanism
of the fastener applier shown in FIG. 14, showing the contact/force
sensing assembly enabling use of the applier in response to desired
contact between the fastener and the targeted tissue region;
[0040] FIGS. 25A and 25B are enlarged views of the distal end of a
fastener applier showing the details of an alternative embodiment
of the fastener drive mechanism;
[0041] FIG. 26A is an enlarged section view of the drive mechanism
of the fastener applier shown in FIGS. 25A and 25B showing a
contact/force sensing assembly that disables the applier in the
absence of desired contact between the fastener and a targeted
tissue region;
[0042] FIGS. 26B and 26C are enlarged section views of the drive
mechanism of the fastener applier shown in FIGS. 25A and 25B,
showing the contact/force sensing assembly enabling use of the
applier in response to desired contact between the fastener and the
targeted tissue region;
[0043] FIG. 27 is a perspective view of a helical fastener that can
be used in association with the fastener applier shown in FIGS. 14,
23, and 24;
[0044] FIG. 28A is a perspective view of a helical fastener that
can be used in association with the fastener applier shown in FIGS.
25A and 25B;
[0045] FIG. 28B is perspective view of a helical fastener that can
be used in association with the fastener applier shown in FIGS. 26A
to 26C;
[0046] FIG. 29 is an enlarged side view, partially in section, of a
fastener applier having an angled applicator end that can be used
to deploy the helical fastener shown in FIG. 27 without use of a
separate directing device;
[0047] FIG. 30 is an enlarged side view, partially in section, of
an alternative embodiment of an angled fastener applier that can be
used to deploy the helical fastener shown in FIG. 27 without use of
a separate directing device;
[0048] FIG. 31 is an enlarged side view, partially in section, of
an alternative embodiment of an angled fastener applier that can be
used to deploy the helical fastener shown in FIG. 27 without use of
a separate directing device, the fastener applier having an
articulating applicator end;
[0049] FIG. 32 is a perspective view of an endovascular prosthesis
shown positioned within an abdominal aortic aneurysm, the
prosthesis including an integrated fastener assembly;
[0050] FIG. 33 is a perspective view of the endovascular prosthesis
shown in FIG. 32, with an intraluminal tool deployed to operatively
interact with the integrated fastener assembly, to temporarily or
permanently anchor the prosthesis to the wall of the vessel;
[0051] FIG. 34 is a side view of a fastener that forms a part of
the integrated fastener assembly shown in FIG. 33, the fastener
having a stem, which is shown in a normally spread-apart condition
before its association with the integrated fastener assembly;
[0052] FIG. 35 is a side view of the fastener shown in FIG. 34, the
fastener stem now being shown in a closed condition and housed
within a grommet that forms a part of the integrated fastener
assembly;
[0053] FIGS. 36 and 37 are side views showing the use of the
intraluminal tool shown in FIG. 33 to apply force to drive the
fastener from its position shown in FIG. 35 and through the vessel
wall;
[0054] FIG. 38 is the integrated fastener assembly after deployment
to anchor a prosthesis to a vessel wall;
[0055] FIG. 39 is a side view showing the use of a tracking wire to
guide a intraluminal tool into contact with a fastener, so that
force can be applied to drive the fastener through the vessel
wall;
[0056] FIG. 40 is an embodiment of a prosthesis delivery catheter
for a prostheses in which the stent structure covers only a portion
of the prosthesis, the catheter including an array of stabilization
struts to help hold the prosthesis in position against the flow of
blood;
[0057] FIG. 41 is another embodiment of a prosthesis delivery
catheter for a prostheses in which the stent structure covers only
a portion of the prosthesis, the catheter including an array of
inverted stabilization struts to help hold the prosthesis in
position against the flow of blood; and
[0058] FIG. 42 is another embodiment of a prosthesis delivery
catheter for a prostheses in which the stent structure covers only
a portion of the prosthesis, the catheter including a stabilization
basket to help hold the prosthesis in position against the flow of
blood.
DETAILED DESCRIPTION OF THE INVENTION
I. Delivering a Prosthesis
[0059] FIG. 1 depicts an endovascular graft delivery catheter 10 as
it is being positioned over a guidewire 12 in a body lumen. The
catheter 10 carries a prosthesis 14 (see FIG. 2), which is placed
at a targeted site, e.g., by radial expansion of the prosthesis 14
(see FIG. 3). After expansion of the prosthesis 14, one or more
fasteners 28 (see FIGS. 15 and 16) are introduced by a fastener
attachment assembly to anchor the prosthesis 14 in place.
[0060] For the purposes of illustration, FIG. 1 shows the targeted
site as being within an abdominal aortic aneurysm 11. The targeted
site can be elsewhere in the body. In the illustrated arrangement,
the prosthesis 14 takes the form of an endovascular graft.
[0061] FIG. 2 depicts the initial stage of graft deployment at the
targeted site. While the deployment method can vary, in the
illustrated embodiment, the delivery catheter 10 has a movable
cover 13, which overlays the graft 14. When the cover 13 is pulled
proximally, the graft 14 is free to radially expand, thereby
enlarging to contact the internal walls of the blood vessel. The
graft 14 is shown to be self-expanding. Alternatively, the graft 14
can utilize an expanding member, such as a balloon or mechanical
expander.
[0062] The process of graft deployment is continued, until the
graft 14 is fully deployed within the vessel. The graft 14 can be
sized and configured to be either straight or bifurcated form. FIG.
3 depicts a completely deployed straight graft 14. FIG. 4 depicts a
completely deployed bifurcated graft 15.
[0063] A. The Prosthesis
[0064] The graft 14 desirably incorporates a support frame or
scaffold 16. The scaffold 16 may be elastic, e.g., comprised of a
shape memory alloy elastic stainless steel, or the like. For
elastic scaffolds, expanding typically comprises releasing the
scaffolding from a constraint to permit the scaffold to self-expand
at the implantation site. In the illustrated arrangement, the cover
13 serves as a radial constraint. Alternatively, placement of a
tubular catheter, delivery sheath, or the like over the scaffold 16
can serve to maintain the scaffold in a radially reduced
configuration. In this arrangement, self-expansion of the scaffold
16 is achieved by pulling back on the radial constraining member,
to permit the scaffold 16 to assume its larger diameter
configuration.
[0065] Alternatively, the scaffold 16 may be constrained in an
axially elongated configuration, e.g., by attaching either end of
the scaffold to an internal tube, rod, catheter or the like. This
maintains the scaffold 16 in the elongated, reduced diameter
configuration. The scaffold 16 may then be released from such axial
constraint in order to permit self-expansion.
[0066] Alternatively, the scaffold 16 may be formed from a
malleable material, such as malleable stainless steel of other
metals. Expansion may then comprise applying a radially expansive
force within the scaffold to cause expansion, e.g., inflating a
scaffold delivery catheter within the scaffold in order to affect
the expansion. In this arrangement, the positioning and deployment
of the endograft can be accomplished by the use of an expansion
means either separate or incorporated into the deployment catheter.
This will allow the endograft to be positioned within the vessel
and partially deployed while checking relative position within the
vessel. The expansion can be accomplished either via a balloon or
mechanical expansion device. Additionally, this expansion
stabilizes the position of the endograft within the artery by
resisting the force of blood on the endograft until the endograft
can be fully deployed.
[0067] The graft 14 may have a wide variety of conventional
configurations. It can typically comprise a fabric or some other
blood semi-impermeable flexible barrier which is supported by the
scaffold 16, which can take the form of a stent structure. The
stent structure can have any conventional stent configuration, such
as zigzag, serpentine, expanding diamond, or combinations thereof.
The stent structure may extend the entire length of the graft, and
in some instances can be longer than the fabric components of the
graft. Alternatively, the stent structure can cover only a small
portion of the prosthesis, e.g., being present at the ends. The
stent structure may have three or more ends when it is configured
to treat bifurcated vascular regions, such as the treatment of
abdominal aortic aneurysms, when the stent graft extends into the
iliac arteries. In certain instances, the stent structures can be
spaced apart along the entire length, or at least a major portion
of the entire length, of the stent-graft, where individual stent
structures are not connected to each other directly, but rather
connected to the fabric or other flexible component of the
graft.
[0068] One illustrative embodiment of the graft scaffold 16 or
stent structure is illustrated in the area broke away in FIG. 4.
Here, the stent structure is in the form of a simple zigzag
pattern, however it is contemplated that the stent design could
involve more complex patterns 17 as depicted in FIG. 5. Although
only one stent structure within the graft is depicted, in FIGS. 4
and 5, it is contemplated that multiple independent stent
structures could be incorporated into the graft, as previously
described.
[0069] FIG. 40 shows an embodiment of a prosthesis delivery
catheter 600 for a prostheses 14 in which the stent structure 16
covers only a portion of the prosthesis, e.g., being present only
at the ends. As shown in FIG. 40, the prosthesis delivery catheter
600 (which is shown deployed over a guidewire 610) includes an
array of stabilization struts 612 that are releasably coupled to
the stent structure 16 at the end of the prosthesis 14, e.g., by
sutures that can be released by pulling on a drawstring (not shown)
that passes through a lumen in the catheter 600. The stabilization
struts 612 hold the self-expanding stent structure 16 in position
against the vessel wall 34, while the remainder of the prosthesis
14 is being deployed (by withdrawal of a delivery sheath 614). The
struts 612 support the stent structure 16 (and thus the overall
prosthesis 14) against the force of blood flow through the vessel
during prosthesis deployment. The catheter 600 can also include a
nose cone 618 at its distal end to diffuse blood flow toward the
vessel wall, to aid in supporting the prosthesis 14 during its
deployment. Upon, deployment of the prosthesis 14, the struts 612
can be detached from the stent structure 14 by pulling upon the
drawstring to release the sutures, and the catheter 600 is
withdrawn over the guidewire 610 through the delivery sheath 614
(the struts 612, freed from the stent structure 16, fold back upon
the catheter 600 during passage through the delivery sheath
614).
[0070] FIG. 41 shows an alternative embodiment of a prosthesis
delivery catheter 700 for a prostheses 14 in which the stent
structure 16 covers only a portion of the prosthesis, e.g., being
present at the ends. As shown in FIG. 40, the prosthesis delivery
catheter 700 (which is also shown deployed over a guidewire 710)
includes an array of inverted stabilization struts 712 that are
releasably coupled to the stent structure 16 at the end of the
prosthesis 14, e.g., by sutures that can be released by pulling on
a drawstring (not shown) that passes through a lumen in the
catheter 700. The inverted stabilization struts 712, like the
struts 612 shown in FIG. 40, hold the self-expanding stent
structure 16 in position against the vessel wall 34, while the
remainder of the prosthesis 14 is being deployed (by withdrawal of
a delivery sheath 714). Like the catheter 600 in FIG. 40, the
catheter 700 can also include a nose cone 718 at its distal end to
diffuse blood flow toward the vessel wall. Upon, deployment of the
prosthesis 14, the struts 712 are detached from the stent structure
14 by pulling upon the drawstring not shown), and the catheter 700
is withdrawn over the guidewire 710 through the delivery sheath 714
(the struts 612, freed from the stent structure 16, fold back upon
the catheter 600 during passage through the delivery sheath
614).
[0071] FIG. 42 shows another alternative embodiment of a prosthesis
delivery catheter 800 for a prostheses 14 in which the stent
structure 16 covers only a portion of the prosthesis, e.g., being
present at the ends. As shown in FIG. 42, the prosthesis delivery
catheter 800 (which is also shown deployed over a guidewire 810)
includes a self-expanding stabilization basket 812. The
stabilization basket 812 holds the self-expanding stent structure
16 in position against the vessel wall, while the remainder of the
prosthesis 14 is being deployed (by withdrawal of a delivery sheath
814). Like the catheters 600 and 700 in FIGS. 40 and 41, the
catheter 800 can also include a nose cone 818 at its distal end to
diffuse blood flow toward the vessel wall. Upon, deployment of the
prosthesis 14, the stabilization basket is placed into a collapsed
condition by withdrawal through the delivery sheath 814, as the
catheter 800 is withdrawn over the guidewire 810.
[0072] In all of the just-described embodiments, the guidewire 610,
710, 810 can be subsequently used to deploy a fastener attachment
assembly for the prosthesis 14, as will be described in greater
detail next.
II. Fastening the Prosthesis
[0073] In a desired embodiment, a fastener attachment assembly is
provided that makes possible intraluminal fastener attachment. The
attachment assembly can be variously constructed.
[0074] A. Two Component Fastener Guide and Attachment Assembly
[0075] In one arrangement, the fastener attachment assembly
comprises a fastener guide or directing component 18 and a fastener
applier component 27. The guide component 18 desirably has a
steerable or deflectable distal tip, which is initially deployed
over the guidewire 12. In use, the guidewire 12 that is used to
deliver and position the prosthesis 14 desirably remains within the
vessel for subsequent deployment of the fastener guide component
18.
[0076] Optionally, the guide component 18 includes a stabilizer for
holding, following removal of the guidewire 12, the deflected tip
against a location in the prosthesis 14, to which a fastener 28 for
the prosthesis 14 is to be applied.
[0077] In this arrangement, the applier component 27 is desirably
deployed through the guide component 18. The fastener applier 27
carries at least one fastener 28 and a fastener drive mechanism 100
for advancing the fastener 28, so that it penetrates the prosthesis
14 and underlying vessel wall, to thereby anchor the prosthesis 14
firmly in place.
1. Fastener Directing Component
[0078] FIG. 6 depicts one embodiment of the directing or guide
component 18 that forms a part of the fastener attachment assembly.
The component 18 takes the form of a directing device 18. The
device 18 has an obturator 19 positioned within a lumen of the
directing device 18, which extends past the distal of the tip of
the directing device. The obturator 19 has a lumen to allow for
delivery of the directing device 18 over the guidewire 12, as shown
in FIG. 7.
[0079] The directing device 18 desirably includes an integrated
stabilizing device 20, which aids in maintaining position of the
directing device 18 within the vessel upon removal of the guidewire
12. In one embodiment, the stabilizing device 20 is spring-loaded
and is positioned for deployment when the obturator 19 and
guidewire 12 are removed (see FIG. 8).
[0080] In the illustrated embodiment (see FIG. 8), the directing
device 18 includes a control assembly 21. In one embodiment the
control assembly 21 features a movable wheel or lever 22, which
operate interior steering wires in a conventional fashion to
deflect the distal tip 23 of the directing device 18 toward a
desired location, as seen in FIG. 9. It is contemplated that the
control assembly for the directing device 18 could be activated
mechanically, electrically, hydraulically or pneumatically. The
control assembly 21 has a through lumen to allow for the passage of
the obturator 19 and applier component 27.
[0081] FIG. 10 depicts an alternative embodiment, in which the
stabilizing device 20 takes the form of a movable strut assembly
24. The movable strut assembly 24 can be activated, e.g., through a
lever 25 on the control assembly (see FIG. 11). In both embodiments
(FIGS. 7 and 10) the stabilizing device 20 is distal to the end of
the directing device.
[0082] In another alternative embodiment (see FIG. 12), the
stabilizing device 20 takes the form of an expandable member 26
adjacent to the distal tip of the directing device. As shown in
FIG. 13, the expandable member 26 can be activated, e.g., through a
lever 25 on the control assembly 21. However it also contemplated
that this type of stabilizing device 20 could also be inflatable.
In all embodiments the stabilizing device could be use to stabilize
the directing device 18 either concentrically or eccentrically
within the vessel.
[0083] In another embodiment, a separate stabilization device could
be used in cooperation with the directing device 18 and to access
the vessel. This separate stabilization device could incorporate
the forms of the stabilizing devices described above, or some other
form of stabilization mechanism.
[0084] 2. Fastener Applier Component
[0085] FIG. 14 shows one embodiment of the applier component 27
that forms a part of the fastener attachment assembly. The
component 27 takes the form of a fastener applier 27. FIG. 15
depicts the fastener applier 27 being deployed through a lumen of
the directing device 18 to the site where a fastener 28 will be
installed.
[0086] Located at the distal end of the fastener applier 27 (see
FIG. 14) is a fastener drive mechanism 100. In the illustrated
embodiment (see FIG. 14A), the drive mechanism 100 includes a
driver 29 that is coupled to a carrier 102. The coupling between
the driver 29 and carrier 102 can take different forms--e.g.,
magnets, graspers, or other suitable mechanical connection. In the
embodiment illustrated in FIG. 14A, the driver 29 and carrier 102
are integrally connected as a single unit.
[0087] The carrier 102 is sized and configured to engage a selected
fastener 28. In FIG. 14A, the fastener takes the form of a helical
fastener of the type shown in FIGS. 18 and 27. As best shown in
FIG. 27, and as will be described in greater detail later, the
helical fastener 28 in FIG. 26 is an open coil 148 with a sharpened
leading tip 142. The proximal end 144 of the fastener 28 includes
an L-shaped leg 146. The L-shape leg 146 desirably bisects the
entire interior diameter of the coil 148; that is, the L-shaped leg
146 extends completely across the interior diameter of the coil
148, as FIG. 27 shows. The L-shaped leg 146 serves to engage the
carrier 102 of the fastener applier 27, which rotates the helical
fastener to achieve implantation. The L-shaped leg 146 also serves
as a stop to prevent the helical fastener from penetrating too far
into the tissue.
[0088] The carrier 102 in FIG. 14A includes a slot 180, which
receives the L-shaped leg 146 to couple the fastener 28 for
rotation with the carrier 102. The turns of the coil 148 rest in
complementary internal grooves 32 that surround the carrier 102.
The grooves 32 could be positioned along the entire length of the
fastener 28 or within a portion of its length.
[0089] The actuation of the drive mechanism 100 can, of course, be
accomplished in various ways, e.g., mechanical (i.e., manual or
hand-powered), electrical, hydraulic, or pneumatic. In the
illustrated embodiment (see FIG. 14B), a drive cable 30 couples the
fastener driver 29 to an electric motor 106 carried in the applier
handle 108. The drive cable 30 is desirably made of a suitable
material that allows for both bending and rotation. Driven by the
motor 106 (which is, in turn, under the control of motor control
unit 31, as will be described later), the drive cable 30 rotates
the driver 29 and, with it, the carrier 102. The carrier 102
imparts rotation and torque to the helical fastener 28 for
implantation in tissue.
[0090] FIG. 16 is an enlarged cross-sectional view of fastener
applier 27 and directing device 18. FIG. 17 is an enlarged
cross-sectional view of the fastener applier 27 with a
cross-section of the fastener driver 29 depicting the engagement
between the fastener driver 29 and helical fastener 28. FIG. 19
depicts the fastener applier 27 during activation of the fastener
drive mechanism 100. Activation of the drive mechanism 100 rotates,
as a unit, the drive shaft 30, the driver 29, the carrier 102, and
helical fastener 28. This rotation causes the helical fastener 28
to travel within the internal grooves 32 of the fastener applier
and into the prosthesis 14 and vessel wall 34 (see FIG. 20). FIG.
21 illustrates a completed helical fastener 28 attachment of the
graft 14 to the vessel wall 34.
[0091] In use, the applier 27 is advanced through the directing
device 18 and into contact with the prosthesis. The operator
actuates the control unit 31 by contacting a control switch 110
(see FIGS. 14 and 14B). This action causes the helical fastener 28
to be rotated off the carrier 102 and through the prosthesis 14 and
into the vessel wall 34. The motor control unit 31 desirably
rotates the drive cable 30 a specific number of revolutions with
each activation command. This can be accomplished by incorporating
a mechanical or electrical counter.
[0092] With the deployment of a fastener 28, the applier 27 is
retrieved through the directing device 18, and another fastener 28
is loaded into the carrier 102. The directing device 18 is
repositioned and stabilized, and the applier 27 is advanced again
through the directing device 18 and into contact with the
prosthesis 14. The operator again actuates the control unit 31 by
contacting the control switch 110 to deploy another fastener 28.
This process is repeated at both proximal and/or distal ends of the
prosthesis 14 until the prosthesis 14 is suitably attached and
sealed to the vessel wall 34. It is contemplated that from about
two to about twelve fasteners 28 may be applied at each end of the
prosthesis 14 to affect anchorage. The fasteners 28 can be applied
in a single circumferentially space-apart row, or may be applied in
more than one row with individual fasteners being axially aligned
or circumferentially staggered.
[0093] FIG. 22 illustrates a perspective view of a graft prosthesis
attached to the vessel wall both proximally and distally. It is
contemplated that the present invention can be used for graft
attachment of both straight and bifurcated grafts within the aorta
and other branch vessels.
[0094] An alternative embodiment of the drive mechanism 100 is
shown in FIGS. 25A and 25B. In this embodiment, the driver 29 is
coupled to a carrier 150, which forms a part of the helical
fastener 28 itself, as also shown in FIG. 28A. As shown in FIG.
28A, the helical fastener 28 is, like the fastener shown in FIG.
27, an open coil 148 with a sharpened leading tip 142. The proximal
end 144 of the fastener 28 includes the carrier 150.
[0095] The carrier 150 includes a slot 182. The slot 182 engages a
drive flange 184 on the driver 29 (see FIG. 25A) to impart rotation
of the driver 29 to rotation of the helical fastener 28 during the
implantation process. Like the L-shaped leg of the fastener shown
in FIG. 27, the carrier 150 also serves as a stop to prevent the
helical fastener from penetrating too far into the tissue.
[0096] The coupling engagement between the carrier 150 and the
driver 29 could be accomplished in various ways, e.g., by separate
graspers or grippers, a magnetic couple, or any other suitable
mechanical connecting means. In the illustrated embodiment, the
driver 29 is made of a magnetized material, and the carrier 150 is
made from a material that is magnetically attracted toward the
magnetized material. Of course, a reverse arrangement of magnetized
and magnetically attracted materials could be used.
[0097] In this arrangement, the motor coupling 132 between the
drive cable 30 and the motor 106 accommodates axial displacement of
the motor cable 30 (left and right in FIGS. 25A and 25B) without
interrupting the drive connection with the motor 106. With the
distal tip of the applier device 27 in contact with the prosthesis
14 (see FIG. 25A), the operator actuates the control unit 31 by
contacting a control switch 110. The control unit 31 commands the
motor 106 to rotate the drive cable 30 to impart rotation to the
driver 29 and the magnetically attached helical fastener 28. This
action causes the magnetically attached helical fastener 28 to be
rotated into prosthesis 14 and the vessel wall 34 (see FIG. 25B).
Due to the magnetic coupling, as the fastener 28 is deployed to the
left in FIG. 25B, the driver 29 moves in tandem with carrier 150
(also to the left in FIG. 25B). Due to the magnetic coupling
between the carrier 150 and the driver 29, the operator must exert
a deliberate separation force to decouple the carrier 150 (and,
with it, the fastener 28) from the driver 29. This arrangement
prevents inadvertent release of a fastener 28.
[0098] As before described, with the deployment of a fastener 28,
the applier 27 is retrieved through the directing device 18, and
another fastener 28 is magnetically coupled to the driver 29. The
directing device 18 is repositioned and stabilized, and the applier
27 is advanced again through the directing device 18 and into
contact with the prosthesis 14. The operator again actuates the
control unit 31 by contacting a control switch 110 to deploy
another fastener 28. This process is repeated at both proximal
and/or distal ends of the prosthesis 14 until the prosthesis 14 is
suitably attached and sealed to the vessel wall 34.
[0099] As indicated in the above description, the outer diameter of
the applier component 27 is desirably sized and configured to pass
through the lumen of the directing component 18, which can take the
form of a suitable steerable guide catheter, to direct the applier
component 27 to the desired location. As also above described, the
applier component 27 is desirably configured to implant one
fastener 28 at a time (a so-called "single fire" approach). This is
believed desirable, because it reduces the complexity of the design
and accommodates access of the applier 27 through tortuous anatomy.
Fastener appliers 27 which carry a single fastener can have a lower
profile and may be more effective and less traumatic than fastener
appliers which carry multiple fasteners. Still, in alternative
embodiments, the applier component 27 may, if desired, be
configured to carry multiple fasteners. Moreover, the fastener
applier 27 may simultaneously deploy multiple fasteners in the
preferred circumferentially spaced-apart space pattern described
above.
[0100] a. Prosthesis/Tissue Contact Sensing
[0101] The fastener applier 27 desirably incorporates a function
that prevents actuation of the motor 106 until the tip of the
applier 27 is in a desired degree of contact with the prosthesis or
tissue surface. This prevents inadvertent discharge of a fastener
28 and/or separation of the fastener 28. This function can be
implemented, e.g., using a contact or force sensor, which is either
mechanical or electrical in design.
[0102] When the fastener applier 27 is of the type shown in FIGS.
14A. 14B, and 14C (see FIGS. 23 and 24), the contact or force
sensing function can, e.g., utilize the distal tip 120 of the
carrier 102 to transmit a contact force. This force can be
transmitted to a force or contact sensing switch 122 located, e.g.,
within the fastener applier handle 108. In this arrangement, the
switch 122 can be part of the electrical circuit between the
actuator switch 110 and the control unit 31.
[0103] In the illustrated embodiment, the switch 122 includes a
stationary switch element 128 (coupled to the interior of the
handle 108) and a movable switch element 130 (carried by the drive
cable 31). In this arrangement, the motor coupling 132 between the
drive cable 30 and the motor 106 accommodates axial displacement of
the motor cable 30 (left and right in FIGS. 23 and 24) without
interrupting the drive connection with the motor 106. The drive
cable 30 is coupled by a bearing 134 to the movable switch element
130, so that the switch element 130 moves in response to movement
of the drive cable 30. The stationary switch element 128 is not
coupled to the movable drive cable 30, which slidably passes
through the switch element 130.
[0104] Due to this arrangement, axial displacement of the drive
cable 30 moves the switch element 130 relative to the switch
element 128. More particularly, displacement of the drive cable 30
to the left in FIG. 23 moves the switch element 130 to the left,
away from the switch element 128. Conversely, displacement of the
drive cable 30 to the right in FIG. 23 moves the switch element 130
to the right, toward the switch element 128.
[0105] A spring 126 normally biases the switch elements 128 and 130
apart, comprising an electrically opened condition. In this
condition, operation of the actuating switch 110 does not serve to
actuate the control unit 31, as the electrically open switch 122
interrupts conveyance of the actuation signal to the motor control
unit 31. When the switch elements 128 and 130 are in the
electrically opened condition, the drive cable 30 is displaced to
the left to position the carrier tip 120 beyond the distal tip 124
of the fastener applier 27. The carrier tip 120 therefore makes
contact with the prosthesis 14 or tissue in advance of the applier
tip 124.
[0106] When the carrier tip 120 contacts the surface of the
prosthesis or tissue with sufficient force to compress the spring
126, the drive cable 30 is displaced against the biasing force of
the spring to the right in FIG. 23. This moves the switch element
130 to the right. Ultimately, contact between the switch elements
128 and 130 will occur, as shown in FIG. 24. The contact
establishes an electrically closed condition. In this condition,
operation of the actuating switch 110 serves to actuate the control
unit 31. As shown in FIGS. 23 and 24, a contact screw 136 can be
provided to adjust the amount of displacement required to close the
switch elements 128 and 130.
[0107] Upon removal of contact force, or in the absence of
sufficient contact force, the spring 126 urges the switch elements
128 and 130 toward the electrically opened condition. The distal
tip of the carrier 102 is located distally beyond the distal tip of
the applier 27.
[0108] It should be appreciated that the translation of movement of
the carrier tip 120 to the switch 122 need not occur along the
entire length of the drive cable 30. For example, the switch 122
can be located in a translation space between the carrier 102 and
the driver 29. In this arrangement, the driver 29, coupled to the
drive cable 30 need not accommodate axial displacement. Instead,
relative movement of the carrier 102 toward the driver 29 in
response to contact with the prosthesis 14 will mechanically couple
the carrier 10 with the driver 29 (e.g., through a slot and flange
connection similar to that shown in FIGS. 25A and 25B), while also
closing the switch 122 to energize the circuit between the actuator
switch 110 and the motor control unit 31.
[0109] When the fastener applier 27 is of the type shown in FIGS.
25A and 25B (see FIGS. 26A, 26B, and 26C), the contact or force
sensing function can, e.g., utilize a force sensing rod 190 that
slidably passes through a central passage 192 in the carrier 150'
(the carrier 150' is shown in FIG. 28B), the driver 29 and the
drive cable 30. The rod 190 is coupled to the movable switch
element 130. In this embodiment, the switch element 130 translates
left and right over the drive cable 30, which rotates on a bearing
134 within the switch element 130.
[0110] As in the preceding embodiment, the spring 126 normally
biases the switch elements 128 and 130 apart, comprising an
electrically opened condition. When the switch elements 128 and 130
are in the electrically opened condition, the force sensing rod 190
is displaced to the left beyond the distal tip 124 of the fastener
applier 27. The force sensing rod 190 therefore makes contact with
the prosthesis 14 or scaffold structure 16 in advance of the
applier tip 124.
[0111] When the rod 190 contacts the surface of the prosthesis or
scaffold structure with sufficient force to compress the spring
126, the rod 190 is displaced against the biasing force of the
spring 126 to the right in FIG. 26A. This moves the switch element
130 to the right. Ultimately, contact between the switch elements
128 and 130 will occur, as shown in FIG. 26B. The contact
establishes an electrically closed condition. In this condition,
operation of the actuating switch 110 serves to actuate the control
unit 31. This action causes the helical fastener 28 to be rotated
into the scaffold structure 16 and into the vessel wall 34 (see
FIG. 26C). Due to the magnetic coupling between the driver 29 and
carrier 150', the driver 29 is moved in tandem with attached
carrier 150' to the left in FIG. 26B, as the fastener 28 is
deployed. Also, due to the magnetic coupling between the carrier
150 and the driver 29, the operator must exert a separation force
to decouple the carrier 150 (and, with it, the fastener 28) from
the driver 29. As before described, this arrangement prevents
inadvertent release of a fastener 28. A contact screw 136 can be
provided to adjust the amount of displacement required to close the
switch elements 128 and 130.
[0112] Upon removal of contact force, or in the absence of
sufficient contact force, the spring 126 urges the switch elements
128 and 130 toward the electrically opened condition, moving the
tip of the rod 190 out beyond the distal tip 124 of the applier
27.
[0113] The contact or force sensing arrangements just described can
also generate an audible and/or visual output to the operator, to
indicate that sufficient contact force between the applier device
27 and the prosthesis or tissue exists.
[0114] B. Angled Component Fastener Guide and Attachment
Assembly
[0115] In another arrangement (see FIG. 29), the fastener
attachment assembly comprises a unitary, angled fastener guide and
applier component 160. In this arrangement, the component 160
includes a fastener drive mechanism 162 that places the carrier 164
holding the fastener 28 in a perpendicular or near perpendicular
position with respect to the prosthesis or tissue. This
configuration eliminates the need for a separate steerable guide
component 18 for the fastener component 27, previously
described.
[0116] The drive mechanism 162 can vary. In the illustrated
embodiment (shown in FIG. 29), the mechanism 162 includes a beveled
drive gear 168 coupled to the drive cable 30. The drive gear 168
operatively meshes with a transfer or pinion gear 170, which is
coupled to the carrier 164. The axes of rotation of the drive gear
168 and pinion gear 170 are offset about ninety degrees, so that
rotation of the drive cable 30 along the axis of the vessel is
translated into rotation of the carrier 164 generally perpendicular
to the wall of the vessel. The fastener guide and applier component
160 can be positioned and stabilized within the vessel in various
ways, e.g., through the use external spring loaded strut or the
like (as shown in association with the directing component 18
discussed above), or by use of an expandable member 166 (as FIG. 29
shows). The expansion member 166 can comprise either a balloon or
mechanical expansion device. The expansion member 166 stabilizes
the position of both the prosthesis and the fastener guide and
applier component 160 within the vessel by resisting the force of
blood until the prosthesis can be anchored.
[0117] As FIG. 30 shows, the fastener guide and applier component
160 can, if desired, provide an angled deployment between the drive
cable 30 and carrier 164 that is somewhat less than ninety-degrees,
to aid in intraluminal manipulation of the carrier into
perpendicular contact position against the wall of the vessel. As
FIG. 31 shows, the fastener guide and applier component 160 can, if
desired, be articulated between the drive cable 30 and carrier 164.
In this arrangement, a remote control mechanism is desirable
provided to move the carrier 164 from a first, generally straight
position (shown in phantom lines in FIG. 31) for deployment to the
targeted site, to a second, articulated position (shown in solid
lines in FIG. 31) for alignment of the carrier 164 in contact
against the vessel wall.
III. The Fasteners
[0118] As illustrated and described thus far, introduction of the
fasteners 28 will typically be affected after the prosthesis 14 has
been initially placed. That is, initial placement of the prosthesis
14 will be achieved by self-expansion or balloon expansion, after
which the prosthesis 14 is secured or anchored in place by the
introduction of a plurality of individual fasteners. The fasteners
28 may be placed only through the fabric of the prosthesis 14,
i.e., avoiding the scaffold structure. Alternately, the fasteners
28 can be introduced into and through portions of the scaffold
structure itself. The prosthesis 14 may include preformed
receptacles, apertures, or grommets, which are specially configured
to receive the fasteners. The fasteners 28 may be introduced both
through the fabric and through the scaffold structure. The
fasteners can be introduced singly, i.e., one at a time, in a
circumferentially spaced-apart pattern over an interior wall of the
prosthesis 14.
[0119] In the exemplary embodiment, the fasteners 28 are helical
fasteners, so that they can be rotated and "screwed into" the
prosthesis 14 and vessel wall. A desired configuration for the
helical fastener 28 (see FIGS. 27, 28A, and 28B) is an open coil
148, much like a coil spring. This configuration allows the
fastener 28 to capture a large area of tissue, which results in
significantly greater holding force than conventional staples,
without applying tissue compression, which can lead to tissue
necrosis.
[0120] As FIGS. 27, 28A, and 28B show, the leading tip 142 of the
helical fastener 28 is desirable sharp to allow it to penetrate
thought the artery wall and/or calcified tissue. This distal tip
142 can be sharpened to cut a helical path through the tissue or it
can be sharpened to a point to penetrate the tissue without
cutting.
[0121] The proximal end 144 of the fastener serves two design
functions. The first function is to engage the carrier 102 of the
fastener applier 27, which rotates the helical fastener during the
implantation process. The second function is to act as a stop to
prevent the helical fastener from penetrating too far into the
tissue.
[0122] In one embodiment (see FIG. 27), the proximal end 144 of the
helical fastener 28 includes an L-shaped leg 146 of the coil 148
bisecting the fastener diameter. The leg 146 of the coil 148 comes
completely across the diameter to prevent the fastener from being
an open coil and to control the depth of penetration into the
tissue. In addition, the leg 146 of the coil 148 can be attached to
a previous coil to strengthen the entire structure and provide a
more stable drive attachment point for the fastener applier. This
attachment could be achieved via welding, adhesive or any other
suitable means.
[0123] Alternatively (as shown in FIGS. 28A and 28B), the proximal
end 144 of the fastener 28 could incorporate a separate cap or
carrier 150 or 150' that serves the same function as the leg 146 of
the coil 148 in FIG. 27. The carrier 150 or 150' could feature
several methods to attach to the fastener applier drive mechanism
100. These include separate graspers or grippers, a magnetic couple
(as previously described), or any other suitable mechanical
connecting means. In FIGS. 28A and 28B, the carrier 150 and 150'
includes a slot 180 and 182' to mate with a drive flange (as
previously described). As also previously described, a magnetic
coupling is implemented between the carrier 150 and 150' and the
corresponding drive member, to prevent inadvertent separation
during use.
[0124] In FIG. 28B, the carrier 150' also includes a passage 152
for holding the contact/force sensing rod 190 shown in FIGS. 26A,
26B, and 26C.
[0125] The fasteners 28 shown in FIGS. 27, 28A, and 28B can be made
from stainless steel or other types of implantable metal, however
it is also envisioned that the fasteners in the above descriptions
could be made from implantable polymers or from a biodegradable
polymer or combinations of all materials thereof. Desirably, a
fastener 28 will have between 2 and 10 turns and will be between 1
mm and 10 mm long. The space between the individual coils will be
between 0.25 mm and 3 mm. The diameter of the fastener 28 will be
between 1 mm and 6 mm.
IV. Prosthesis with Integrated Fastener Assembly
[0126] FIG. 32 shows a prosthesis 500 that includes at least one
integrated fastener assembly 502. FIG. 32 shows the prosthesis 500
deployed in a targeted intraluminal region, in particular, within
an abdominal aortic aneurysm 504. The prosthesis 500 can be
deployed elsewhere in the body.
[0127] The prosthesis 500 desirably includes a fabric material or
the like carried by a support frame or scaffold 504, as previously
described. The scaffold 504 can be made, e.g., from an elastic
material that self-expands radially during deployment from a
sheath, or from a malleable material that expands radially in
response to a radially expansive force applied within the scaffold
by a balloon or a mechanical expansion device.
[0128] Following deployment of the prosthesis 500 in the targeted
region, the integrated fastener assembly 502 on the prosthesis 500
is manipulated to anchor the prosthesis 500 to the vessel wall. In
the illustrated embodiment, the prosthesis 500 carries two
integrated fastener assemblies 502, one in each end region of the
prosthesis 500.
[0129] In the illustrated embodiment, each fastener assembly 502 is
imbedded in a reinforced flange area 506 in the respective end
region. Each fastener assembly 502 comprises an array of fasteners
508 circumferentially spaced about the flange 506. The number of
fasteners 508 in the array can vary, e.g., from about two to about
twelve fasteners on each flange area 506. The configuration of the
array can also vary, e.g., in the circumferential array, the
fasteners 508 can by axially spaced apart as well.
[0130] The fasteners 508 can be formed of a metal or plastic
material and can be variously constructed. In the illustrated
embodiment, each fastener 508 includes a disc-shaped head 512 and a
stem 514 that is bifurcated into two wings 516 and 518, which are
joined by a plastic or memory material hinge region 520. The
material of the hinge region 520 is formed with a resilient memory
that biases the wings 516 and 518 to a spread-apart condition (as
FIG. 34 shows).
[0131] Each fastener 508 is carried within a grommet 510 on the
flange area 506 (see FIG. 35). When the hinge region 520 is
confined within the grommet 510 (as FIG. 35 shows), the wings 516
and 518 are retained against the resilient memory in an adjacent,
closed condition. In response to the application of a pushing or
punching force on the head 512 (see FIG. 35), the wings 516 and 518
are advanced in the closed condition out of the grommet 510, and
into and through the adjacent vessel wall (see FIG. 36). Upon
continued advancement, the hinge region 520 is freed from the
confines of the grommet 510 (see FIG. 37). As a result, the wings
516 and 518 resiliently spring into their normal spread-apart
condition.
[0132] In this arrangement, an intraluminal tool 522 (see FIG. 33)
is deployed into the prosthesis 500 to exert a pushing or punching
force upon the head 512 of a given fastener 508. In the illustrated
embodiment, the tool 522 comprises a catheter 524 that carries a
punch member 526 at its distal end. In a desired arrangement, the
distal end of the catheter 524 is steerable, to aid in establishing
point contact between the punch member 526 and the head 512 of the
given fastener 508. The head 512 can include a recess 528 to
receive and stabilize the tip of the punch member 526 with respect
to the head 512 during use (see FIG. 34).
[0133] In use, the punch member 526 is manipulated to apply a
pushing or punching force upon the selected fastener head 512. As
FIGS. 35 and 36 show, the application of the pushing force by the
punch member 526 forces the wings 516 and 518 against the near side
of the vessel wall 34. The wings 516 and 518 are still in their
closed condition, because the hinge region 520 is still confined
within the grommet 510. The closed wings 516 and 518 form an
obturator that penetrates tissue as it advances to the far side of
the vessel wall. As the hinge region 510 is freed from the grommet
510 (FIG. 37), the wings 516 and 518 resiliently return to their
spread-apart condition against the far side of the vessel wall.
Upon removal of the punch member 526 (see FIG. 38), the head 512
and spread-apart wings 516 and 518 remain in their mutually opposed
condition in the vessel wall, to secure the prosthesis 500 against
the vessel wall. In use, the physician locates and manipulates the
punch member 526 in succession against each fastener 508, to
complete the anchorage of the prosthesis 500 to the vessel
wall.
[0134] In one embodiment (see FIG. 39), each fastener 508 can
include a tracking wire 530 that is releasably coupled to the head
512. The tracking wire 530 extends from the head 512 outside the
body for access outside the vessel. In this arrangement, the punch
member 526 includes a lumen to accommodate passage of the tracking
wire 530. The tracking wire 530 guides the punch member 526 in an
intraluminal path to the respective fastener 508. After the punch
member 526 is manipulated to drive the fastener 508 into the vessel
wall, the punch member 526 can be withdrawn over the tracking wire
530. The tracking wire 530 can be released from the now-secured
head 512, e.g., by applying a moderate pulling force upon the
tracking wire 530. The tracking wire 530 can then be withdrawn. The
punch member 526 is sequentially guided over another tracking wire
530 for interaction with another one of the fasteners 508, until a
desired degree of anchorage is achieved.
[0135] In an alternative embodiment, an integrated fastener
assembly 502 on the prosthesis 500 can be used to temporarily tack
the prosthesis 500 in place while a permanent anchoring technique
is carried out. For example, in this arrangement, after using the
integrated fastener assembly 502 to temporarily hold the prosthesis
500 in a desired location, the separate helical fasteners 28 are
deployed in the manner previously described, to permanently anchor
the prosthesis 500 against the vessel wall.
[0136] It will be appreciated that the components and/or features
of the preferred embodiments described herein may be used together
or separately, while the depicted methods and devices may be
combined or modified in whole or in part. It is contemplated that
the components of the directing device, fastener applier and
helical fastener may be alternately oriented relative to each
other, for example, offset, bi-axial, etc. Further, it will be
understood that the various embodiments may be used in additional
procedures not described herein, such as vascular trauma, arterial
dissections, artificial heart valve attachment and attachment of
other prosthetic device within the vascular system and generally
within the body.
[0137] The preferred embodiments of the invention are described
above in detail for the purpose of setting forth a complete
disclosure and for the sake of explanation and clarity. Those
skilled in the art will envision other modifications within the
scope and sprit of the present disclosure.
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