U.S. patent application number 12/857115 was filed with the patent office on 2011-05-19 for method and apparatus for effecting a minimally invasive distal anastomosis for an aortic valve bypass.
Invention is credited to Richard M. Beane, Ronald Boudreau, James Alan Crunkleton, Anthony G. Liepert, Joseph L. Smith, JR..
Application Number | 20110118764 12/857115 |
Document ID | / |
Family ID | 43586549 |
Filed Date | 2011-05-19 |
United States Patent
Application |
20110118764 |
Kind Code |
A1 |
Beane; Richard M. ; et
al. |
May 19, 2011 |
METHOD AND APPARATUS FOR EFFECTING A MINIMALLY INVASIVE DISTAL
ANASTOMOSIS FOR AN AORTIC VALVE BYPASS
Abstract
A connector for joining a first hollow structure to the side
wall of a second hollow structure, the connector comprising: a
first component comprising: an inner collar for disposition within
the interior of the second hollow structure, the inner collar
having a toroidal configuration characterized by an outer perimeter
and an inner perimeter, with the inner collar being flexible; a
hollow body connected to the inner collar and upstanding therefrom,
the hollow body of the inner collar being aligned with the inner
perimeter of the inner collar; and a graft element mounted to the
inner collar and forming a conduit extending through the hollow
body and the inner perimeter of the inner collar, the graft being
formed out of a fluid-retaining material; and a second component
for disposition outside the second hollow structure, the second
component comprising an outer collar and a hollow body connected to
the outer collar, the outer collar having a toroidal configuration
characterized by an outer perimeter and an inner perimeter, with
the hollow body of the outer collar being aligned with the inner
perimeter of the outer collar; the hollow body of the second
component being sized for coaxial disposition over the hollow body
of the first component so that the outer collar of the second
component can be adjustably positioned relative to the inner collar
of the first component and so that the conduit of the graft element
provides fluid communication between (i) the region beyond the
inner collar, and (ii) the region beyond the hollow body of the
first component.
Inventors: |
Beane; Richard M.; (Hingham,
MA) ; Boudreau; Ronald; (Boxborough, MA) ;
Crunkleton; James Alan; (Weston, MA) ; Liepert;
Anthony G.; (Lincoln, MA) ; Smith, JR.; Joseph
L.; (Concord, MA) |
Family ID: |
43586549 |
Appl. No.: |
12/857115 |
Filed: |
August 16, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61234075 |
Aug 14, 2009 |
|
|
|
Current U.S.
Class: |
606/153 |
Current CPC
Class: |
A61B 17/11 20130101;
A61B 2017/1107 20130101; A61B 2017/00243 20130101; A61B 2017/1132
20130101; A61B 2017/1121 20130101; A61B 2017/1135 20130101; A61B
2017/1139 20130101; A61B 17/1114 20130101 |
Class at
Publication: |
606/153 |
International
Class: |
A61B 17/11 20060101
A61B017/11 |
Claims
1. A connector for joining a first hollow structure to the side
wall of a second hollow structure, the connector comprising: a
first component comprising: an inner collar for disposition within
the interior of the second hollow structure, the inner collar
having a toroidal configuration characterized by an outer perimeter
and an inner perimeter, with the inner collar being flexible; a
hollow body connected to the inner collar and upstanding therefrom,
the hollow body of the inner collar being aligned with the inner
perimeter of the inner collar; and a graft element mounted to the
inner collar and forming a conduit extending through the hollow
body and the inner perimeter of the inner collar, the graft being
formed out of a fluid-retaining material; and a second component
for disposition outside the second hollow structure, the second
component comprising an outer collar and a hollow body connected to
the outer collar, the outer collar having a toroidal configuration
characterized by an outer perimeter and an inner perimeter, with
the hollow body of the outer collar being aligned with the inner
perimeter of the outer collar; the hollow body of the second
component being sized for coaxial disposition over the hollow body
of the first component so that the outer collar of the second
component can be adjustably positioned relative to the inner collar
of the first component and so that the conduit of the graft element
provides fluid communication between (i) the region beyond the
inner collar, and (ii) the region beyond the hollow body of the
first component.
2. A connector according to claim 1 wherein the hollow body of the
second component is connected to the hollow body of the first
component with a ratchet mechanism.
3. A connector according to claim 1 wherein the inner collar is
ovoid.
4. A connector according to claim 1 wherein the outer collar is
ovoid.
5. A connector according to claim 1 wherein the hollow body of the
first component is ovoid.
6. A connector according to claim 1 wherein the hollow body of the
second component is ovoid.
7. A connector according to claim 1 wherein the various elements of
the first component are formed separate from one another, and
further wherein the various elements of the first component are
assembled during manufacture so as to form a single integral
assembly.
8. A connector according to claim 1 wherein the inner collar
comprises a superelastic material.
9. A connector according to claim 1 wherein the inner collar
comprises a plurality of elements disposed substantially parallel
to one another.
10. A connector according to claim 1 wherein the hollow body of the
first component comprises a plurality of L-shaped support arms
extending therefrom, and further wherein the inner collar is
carried by the L-shaped support arms.
11. A connector according to claim 1 wherein the hollow body of the
first component is molded about the inner collar.
12. A connector according to claim 1 wherein the inner collar is
enveloped with graft material, and further wherein the graft
element is secured to the graft material.
13. A delivery instrument for delivering a connector for joining a
first hollow structure to the side wall of a second hollow
structure, the delivery instrument comprising: a hollow column; at
least one traction arm pivotally mounted to the hollow column so as
to selectively radially project a toe of the traction arm; a rod
movably mounted to the hollow column and having a clamp at the
distal end thereof, the rod being adapted to selectively engage the
at least one traction arm so as to cause the at least one traction
arm to radially project the toe of the at least one traction arm;
and at least one collar actuator slidably mounted to the hollow
column.
14. A delivery instrument according to claim 13 wherein the rod is
movably disposed within the hollow column.
15. A delivery instrument according to claim 13 wherein the at
least one collar actuator is movably mounted to the exterior of the
hollow column.
16. A delivery instrument according to claim 13 wherein
longitudinal movement of the rod causes the rod to selectively
engage the at least one traction arm.
17. A delivery instrument according to claim 13 further comprising
a spring for yieldably biasing the toe of the at least one traction
arm radially inwardly.
18. A delivery instrument according to claim 17 wherein there are
two traction arms, the two traction arms are diametrically opposed
to one another, and the spring comprises a garter spring for
inwardly biasing the toes of the two traction arms.
19. A delivery instrument according to claim 13 wherein the hollow
column is ovoid.
20. A delivery instrument according to claim 19 wherein the at
least one collar actuator is ovoid.
21. A delivery instrument according to claim 13 wherein a plurality
of collar actuators are provided.
22. A delivery instrument according to claim 21 wherein the
plurality of collar actuators can be separately actuated.
23. A system for joining a first hollow structure to the side wall
of a second hollow structure, the system comprising: a connector
comprising: a first component comprising: an inner collar for
disposition within the interior of the second hollow structure, the
inner collar having a toroidal configuration characterized by an
outer perimeter and an inner perimeter, with the inner collar being
flexible; a hollow body connected to the inner collar and
upstanding therefrom, the hollow body of the inner collar being
aligned with the inner perimeter of the inner collar; and a graft
element mounted to the inner collar and forming a conduit extending
through the hollow body and the inner perimeter of the inner
collar, the graft being formed out of a fluid-retaining material; a
second component for disposition outside the second hollow
structure, the second component comprising an outer collar and a
hollow body connected to the outer collar, the outer collar having
a toroidal configuration characterized by an outer perimeter and an
inner perimeter, with the hollow body of the outer collar being
aligned with the inner perimeter of the outer collar; the hollow
body of the second component being sized for coaxial disposition
over the hollow body of the first component so that the outer
collar of the second component can be adjustably positioned
relative to the inner collar of the first component and so that the
conduit of the graft element provides fluid communication between
(i) the region beyond the inner collar, and (ii) the region beyond
the hollow body of the first component; and a delivery instrument
for delivering the connector to the second hollow structure, the
delivery instrument comprising: a hollow column; at least one
traction arm pivotally mounted to the distal end of the hollow
column so as to selectively radially project a toe of the traction
arm; a rod movably mounted to the hollow column and having a clamp
at the distal end thereof, the rod being adapted to selectively
engage the at least one traction arm so as to cause the at least
one traction arm to radially project the toe of the at least one
traction arm; and at least one collar actuator slidably mounted to
the hollow column; the connector being mounted to the delivery tool
such that the hollow body of the first component is mounted
coaxially on the hollow column of the delivery instrument, and the
at least one collar actuator is aligned with the hollow body of the
second component.
24. A method for joining a first hollow structure to the side wall
of a second hollow structure, the method comprising: providing a
connector having (i) a first component comprising an inner collar
and a hollow graft element mounted to the inner collar and
extending therefrom, and (ii) a second component comprising an
outer collar; forming an opening in the side wall of the second
hollow structure; positioning the inner collar of the first
component within the interior of the second hollow structure, with
the graft element extending through the side wall of the second
hollow structure; and advancing the outer collar of the second
component toward the inner collar of the first component so as to
clamp the side wall of the second hollow structure
therebetween.
25. A method according to claim 24 further comprising connecting
the graft element to the first hollow structure.
26. A method according to claim 24 wherein the inner collar of the
first component is flexible, and further wherein positioning the
inner collar of the first component within the interior of the
second hollow structure comprises folding the inner collar along an
axis thereof prior to inserting the inner collar into the second
hollow structure, and thereafter restoring the inner collar to its
initial configuration after insertion of the inner collar into the
second hollow structure.
27. A method according to claim 26 wherein the first component
comprises a resilient structure, and further wherein folding the
inner collar along an axis thereof includes restraining the inner
collar in a folded configuration with a restraint, and wherein
restoring the inner collar to its initial configuration includes
releasing the restraint.
28. A method according to claim 26 wherein the inner collar
comprises an ovoid structure, and further wherein said axis
comprises the long axis of the ovoid structure.
29. A method according to claim 27 wherein the restraint comprises
a clothespin clamp.
30. A method according to claim 29 wherein the clothespin clamp is
disposed within the interior of the graft element.
31. A method according to claim 24 wherein the inner collar
comprises a neck upstanding from the remainder of the inner
collar.
32. A method according to claim 31 wherein the outer collar is
configured to be passed over the neck.
33. A method according to claim 24 wherein the inner collar and the
outer collar are adjustably connected to one another by a ratchet
mechanism.
34. A method according to claim 24 wherein the inner collar
comprises a shape memory alloy.
35. A method according to claim 24 wherein the inner collar
conforms to the curvature of the inside wall of the second hollow
body.
36. A method according to claim 24 wherein the outer collar
conforms to the curvature of the outer wall of the second hollow
body.
37. A method according to claim 24 wherein the inner collar is
enveloped with graft material.
38. A method according to claim 24 wherein fluid flow through the
second hollow structure is halted prior to forming an opening in
the side wall of the second hollow structure.
39. A method according to claim 38 wherein fluid flow is halted by:
delivering a first balloon within the lumen of the second hollow
structure proximal to where the opening is to be formed in the side
wall of the second hollow structure; inflating the first balloon
within the lumen of the second hollow structure; delivering a
second balloon within the lumen of the second hollow structure
distal to where the opening is to be formed in the side wall of the
second hollow structure; and inflating the second balloon within
the lumen of the second hollow structure.
Description
REFERENCE TO PENDING PRIOR PATENT APPLICATION
[0001] This patent application claims benefit of pending prior U.S.
Provisional Patent Application Ser. No. 61/234,075, filed Aug. 14,
2009 by Richard M. Beane et al. for MINIMALLY INVASIVE DISTAL
ANASTOMOSIS FOR AORTIC VALVE BYPASS (Attorney's Docket No.
CORREX-47 PROV), which patent application is hereby incorporated
herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates to surgical methods and apparatus in
general, and more particularly to surgical methods and apparatus
for effecting an aortic valve bypass.
BACKGROUND OF THE INVENTION
[0003] Aortic valve bypass is a proven procedure for relieving
critical aortic valve stenosis. This procedure comprises the
deployment of a bypass conduit, having a prosthetic valve disposed
therein, between the left ventricle and the descending aorta. This
approach allows blood to be pumped from the left ventricle into the
descending aorta without requiring removal of the dysfunctional
native aortic valve. See FIG. 1.
[0004] In an aortic valve bypass procedure, the connection of the
bypass conduit to the descending aorta is commonly referred to as
the "distal anastomosis", and is currently one of the more
difficult and time-consuming elements of an aortic valve bypass
procedure.
[0005] Currently, in order to effect the distal anastomosis, it is
necessary to perform an anterior lateral thoracotomy of
approximately six inch length in order to gain sufficient access to
the descending aorta. The descending aorta is side-clamped so as to
engage, but not occlude, the artery. Then a longitudinal slit is
made in the clamped portion of the artery wall, and a graft (e.g.,
the distal end of the bypass conduit, or an element which is to be
secured to the distal end of the bypass conduit), typically 14-20
mm in diameter, is sutured in place, substantially perpendicular to
the side wall of the descending aorta, so as to establish the
desired fluid connection. Once the perimeter of the graft has been
secured to the slit aortic wall, the side clamp can be released and
the distal anastomosis is complete.
[0006] With respect to the foregoing, it should be appreciated that
the thickness of the side wall of the descending aorta can vary
considerably from patient to patient. Factors influencing the
thickness of the side wall of the descending aorta can include, but
are not limited to, the presence of exterior fat and connective
tissue, interior calcium deposits, and interior ulcerations. In
practice, the thickness of the side wall of the descending aorta
can vary from about 1 mm to about 4 mm in thickness. This variation
in the thickness of the side wall of the descending aorta is a
factor which may need to be taken into account when forming the
distal anastomosis.
[0007] Aortic valve bypass is not currently a common procedure, at
least in part due to the relatively difficult and time-consuming
nature of the distal anastomosis. Furthermore, aortic valve bypass
cannot currently be considered to be a minimally invasive
procedure, due to the need to provide an anterior lateral
thoracotomy of approximately 6 inch length. However, reducing the
size of the thoracotomy with the current procedure is problematic
at best, since reduced access to the descending aorta makes
cross-clamping and suturing all the more difficult and
time-consuming. Also, when the ribs are spread to create access to
the thoracic cavity, the ribs can sometimes fracture, thereby
causing additional trauma to the patient.
[0008] Consequently, there is a need for an improved method and
apparatus for effecting the distal anastomosis in an aortic valve
bypass procedure.
SUMMARY OF THE INVENTION
[0009] These and other objects of the present invention are
addressed by the provision and use of a novel method and apparatus
for effecting the distal anastomosis in an aortic valve bypass
procedure.
[0010] In one form of the invention, there is provided a connector
for joining a first hollow structure to the side wall of a second
hollow structure, the connector comprising:
[0011] a first component comprising: [0012] an inner collar for
disposition within the interior of the second hollow structure, the
inner collar having a toroidal configuration characterized by an
outer perimeter and an inner perimeter, with the inner collar being
flexible; [0013] a hollow body connected to the inner collar and
upstanding therefrom, the hollow body of the inner collar being
aligned with the inner perimeter of the inner collar; and [0014] a
graft element mounted to the inner collar and forming a conduit
extending through the hollow body and the inner perimeter of the
inner collar, the graft being formed out of a fluid-retaining
material; and
[0015] a second component for disposition outside the second hollow
structure, the second component comprising an outer collar and a
hollow body connected to the outer collar, the outer collar having
a toroidal configuration characterized by an outer perimeter and an
inner perimeter, with the hollow body of the outer collar being
aligned with the inner perimeter of the outer collar;
[0016] the hollow body of the second component being sized for
coaxial disposition over the hollow body of the first component so
that the outer collar of the second component can be adjustably
positioned relative to the inner collar of the first component and
so that the conduit of the graft element provides fluid
communication between (i) the region beyond the inner collar, and
(ii) the region beyond the hollow body of the first component.
[0017] In another form of the invention, there is provided a
delivery instrument for delivering a connector for joining a first
hollow structure to the side wall of a second hollow structure, the
delivery instrument comprising:
[0018] a hollow column;
[0019] at least one traction arm pivotally mounted to the hollow
column so as to selectively radially project a toe of the traction
arm;
[0020] a rod movably mounted to the hollow column and having a
clamp at the distal end thereof, the rod being adapted to
selectively engage the at least one traction arm so as to cause the
at least one traction arm to radially project the toe of the at
least one traction arm; and
[0021] at least one collar actuator slidably mounted to the hollow
column.
[0022] In another form of the invention, there is provided a system
for joining a first hollow structure to the side wall of a second
hollow structure, the system comprising:
[0023] a connector comprising: [0024] a first component comprising:
[0025] an inner collar for disposition within the interior of the
second hollow structure, the inner collar having a toroidal
configuration characterized by an outer perimeter and an inner
perimeter, with the inner collar being flexible; [0026] a hollow
body connected to the inner collar and upstanding therefrom, the
hollow body of the inner collar being aligned with the inner
perimeter of the inner collar; and [0027] a graft element mounted
to the inner collar and forming a conduit extending through the
hollow body and the inner perimeter of the inner collar, the graft
being formed out of a fluid-retaining material; [0028] a second
component for disposition outside the second hollow structure, the
second component comprising an outer collar and a hollow body
connected to the outer collar, the outer collar having a toroidal
configuration characterized by an outer perimeter and an inner
perimeter, with the hollow body of the outer collar being aligned
with the inner perimeter of the outer collar; [0029] the hollow
body of the second component being sized for coaxial disposition
over the hollow body of the first component so that the outer
collar of the second component can be adjustably positioned
relative to the inner collar of the first component and so that the
conduit of the graft element provides fluid communication between
(i) the region beyond the inner collar, and (ii) the region beyond
the hollow body of the first component; and
[0030] a delivery instrument for delivering the connector to the
second hollow structure, the delivery instrument comprising: [0031]
a hollow column; [0032] at least one traction arm pivotally mounted
to the distal end of the hollow column so as to selectively
radially project a toe of the traction arm; [0033] a rod movably
mounted to the hollow column and having a clamp at the distal end
thereof, the rod being adapted to selectively engage the at least
one traction arm so as to cause the at least one traction arm to
radially project the toe of the at least one traction arm; and
[0034] at least one collar actuator slidably mounted to the hollow
column;
[0035] the connector being mounted to the delivery tool such that
the hollow body of the first component is mounted coaxially on the
hollow column of the delivery instrument, and the at least one
collar actuator is aligned with the hollow body of the second
component.
[0036] In another form of the invention, there is provided a method
for joining a first hollow structure to the side wall of a second
hollow structure, the method comprising:
[0037] providing a connector having (i) a first component
comprising an inner collar and a hollow graft element mounted to
the inner collar and extending therefrom, and (ii) a second
component comprising an outer collar;
[0038] forming an opening in the side wall of the second hollow
structure;
[0039] positioning the inner collar of the first component within
the interior of the second hollow structure, with the graft element
extending through the side wall of the second hollow structure;
and
[0040] advancing the outer collar of the second component toward
the inner collar of the first component so as to clamp the side
wall of the second hollow structure therebetween.
BRIEF DESCRIPTION OF THE DRAWINGS
[0041] These and other objects and features of the present
invention will be more fully disclosed or rendered obvious by the
following detailed description of the preferred embodiments of the
invention, which is to be considered together with the accompanying
drawings wherein like numbers refer to like parts, and further
wherein:
[0042] FIG. 1 is a schematic view showing an aortic valve
bypass;
[0043] FIG. 2 is a schematic view showing a novel locking collar
connector formed in accordance with the present invention and being
used to form a distal anastomosis;
[0044] FIGS. 3-7 are schematic views showing various components of
the locking collar connector of FIG. 2;
[0045] FIG. 8 is a schematic view showing the locking collar
connector of FIG. 2 mounted to a novel delivery instrument also
formed in accordance with the present invention;
[0046] FIGS. 9-12 are schematic views showing various aspects of
the delivery instrument and locking collar connector shown in FIG.
8, with FIG. 9 being a sectional view taken through line 9-9 of
FIG. 8; with FIG. 10 being an enlarged end view of the distal end
of the delivery instrument and locking collar connector of FIG. 8;
with FIG. 11 being an end view like that of FIG. 10, but with the
graft material removed for clarity of illustration; with FIG. 12
being an enlarged side view of the distal end of the delivery
instrument and locking collar connector, but with the graft
material removed for clarity of illustration;
[0047] FIGS. 13-15 are schematic views showing a distal anastomosis
being formed with the locking collar connector and delivery
instrument of FIG. 8; and
[0048] FIG. 16 is a schematic view showing an alternative form of
locking collar connector formed in accordance with the present
invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0049] The present invention comprises a novel method and apparatus
for effecting the distal anastomosis in an aortic valve bypass
procedure. More particularly, the present invention comprises the
provision and use of a novel locking collar connector to effect the
distal anastomosis in an aortic valve bypass procedure. This novel
locking collar connector allows the distal anastomosis to be
effected quickly and safely, while requiring significantly less
access to the anastomosis site and without requiring suturing to
the descending aorta. Significantly, hemostasis is effectively
maintained at substantially all times, so that the distal
anastomosis can be carried out while the heart is beating.
Locking Collar Connector
[0050] Looking now at FIGS. 2-7, there is shown a novel locking
collar connector 5 which comprises one preferred form of the
present invention. Locking collar connector 5 generally comprises a
ratchet bracket 10 (FIGS. 2, 3, 5 and 6), an inner collar 15 (FIGS.
2, 4, 5 and 6), a graft conduit 20 (FIGS. 2 and 6), and an outer
collar 25 (FIGS. 2 and 7). In one preferred form of the present
invention, and as will hereinafter be discussed in further detail,
ratchet bracket 10, inner collar 15, and graft conduit 20 are
assembled into a single integral assembly 27 (FIG. 6) during
manufacture, and outer collar 25 (FIG. 7) is joined to this single
integral assembly 27 during use (FIG. 2).
[0051] Ratchet bracket 10 is shown in greater detail in FIG. 3.
More particularly, ratchet bracket 10 generally comprises a hollow
ovoid body 30 having a distal end 35, a proximal end 40, and a
lumen 45 extending therebetween. A pair of L-shaped support arms 50
extend distally, and radially outwardly, from distal end 35 of
hollow ovoid body 30. Ratchet teeth 55 are provided on the exterior
surface of hollow ovoid body 30. Preferably two sets of ratchet
teeth 55 are provided on the exterior surface of hollow ovoid body
30, with the two sets of ratchet teeth being disposed in
diametrically-opposed disposition, in the manner shown in FIG. 3.
As will hereinafter be discussed, graft conduit 20 extends through
lumen 45 of hollow ovoid body 30 (FIG. 6), L-shaped support arms 50
are configured to support inner collar 15 adjacent to the distal
end of hollow ovoid body 30 (FIGS. 5 and 6), and the two sets of
ratchet teeth 55 are configured to be engaged by corresponding
elements of outer collar 25 (FIG. 2).
[0052] Inner collar 15 (FIGS. 2 and 4-6) comprises a generally
ovoid body 60 having an ovoid outer perimeter 65 and an ovoid
central hole 70. Inner collar 15 is preferably constructed from a
flat sheet of 0.009'' thick Nitinol, which is heat-treated while
constrained onto the outer diameter of a suitable heat-treat
mandrel (about 1.5 inches in diameter) so as to form a resilient
saddle-like structure. Alternatively, inner collar 15 can be formed
out of other suitable materials. As noted above, and as will
hereinafter be discussed, inner collar 15 is intended to be mounted
to L-shaped support arms 50 of hollow ovoid body 30 (FIGS. 5 and
6). Furthermore, and as will hereinafter be discussed, inner collar
15 is provided with a spring configuration (e.g., because of its
Nitinol construction) which, when inner collar 15 is deployed
within the interior of the descending aorta, can exert a
substantial sealing force against the inner wall of the descending
aorta.
[0053] Graft conduit 20 (FIGS. 2 and 6) comprises a generally
tubular structure which is preferably constructed out of woven
polyester graft (e.g., Vascutek GelWeave.TM.). Other graft
materials, including Gore-Tex.RTM. fabric or Vascutek Triplex.TM.
material, can also be utilized to form graft conduit 20. As noted
above, and as will hereinafter be discussed, graft conduit 20 is
configured to extend through lumen 45 of hollow ovoid body 30 (FIG.
6).
[0054] As noted above, ratchet bracket 10, inner collar 15 and
graft conduit 20 are intended to be assembled into a single
integral assembly 27 (FIG. 6) during manufacture, and outer collar
25 is intended to be joined to this integral assembly during use
(FIG. 2). More particularly, inner collar 15 is preferably attached
to L-shaped support arms 50 of ratchet bracket 10 by molding the
ratchet bracket about inner collar 15 so that the inner collar
resides on the L-shaped support arms of the ratchet bracket (FIG.
5). Woven graft (e.g., Vascutek GelWeave.TM.) 75 (FIG. 6) is then
sewn onto inner collar 15 so as to envelop both sides of the inner
collar 15 (i.e., so as to envelop both of the oval faces 76, 77),
preferably by stitching the woven graft on both the inner and outer
diameters of inner collar 15. Finally, the distal end of graft
conduit 20 is sewn (e.g., at a fluid-tight seam 80) to the woven
graft 75 covering inner collar 15 (FIG. 6). Fluid-tight seam 80 is
preferably on the inner edge of the Nitinol oval, as shown in FIG.
6. Thus, the distal end of the lumen of graft conduit 20 opens on
the ovoid central hole 70 of inner collar 15, with inner collar 15
providing a resilient ovoid flange at the distal end of graft
conduit 20 (see FIG. 6).
[0055] Significantly, with this construction, ratchet bracket 10
remains primarily outside of graft conduit 20 and is not covered
with graft material; only the two L-shaped support arms 50 (molded
onto the Nitinol oval of inner collar 15) are enclosed in graft
material. The two resulting penetrations through the graft layer
(i.e., at the locations where the distal end of graft conduit
engages the two L-shaped support arms 50) are sutured tightly in
order to eliminate potential leak paths.
[0056] Outer collar 25 (FIGS. 2 and 7) comprises a hollow ovoid
body 85 having a distal end 90, a proximal end 95, and lumen 100
extending therebetween. A flange 105 is mounted to distal end 90 of
hollow ovoid body 85. A pair of ratchet arms 110, including ratchet
teeth 115 thereon, are spring mounted to hollow ovoid body 85. As
will hereinafter be discussed, hollow ovoid body 85 of outer collar
25 is intended to be slid over hollow ovoid body 30 of ratchet
bracket 10 so that flange 105 of outer collar 25 opposes inner
collar 15, with ratchet teeth 115 of outer collar 25 engaging
ratchet teeth 55 of ratchet bracket 10. Outer collar 25 is
preferably molded out of a medical grade acetal. Other materials
suitable for permanent implant, such as silicone or polypropylene,
can also be used.
[0057] In use, and as will hereinafter be discussed, an opening is
made in the side wall of the descending aorta; the single integral
assembly 27 (FIG. 6) of ratchet bracket 10, inner collar 15 and
graft conduit 20 is maneuvered so that inner collar 15 is
positioned within the interior of the descending aorta while hollow
ovoid body 30 and graft conduit 20 extend out the side wall of the
descending aorta; and then hollow ovoid body 85 of outer collar 25
is slid down over graft conduit 20 and hollow ovoid body 30 of
ratchet bracket 10 until flange 105 of outer collar 25 engages the
outer wall of the descending aorta and ratchet teeth 115 of outer
collar 25 engage ratchet teeth 55 of ratchet bracket 10, with the
side wall of the descending aorta being securely clamped between
inner collar 15 and flange 105 of outer collar 25, and with graft
conduit 20 in fluid communication with the interior of the
descending aorta. In this way, the distal anastomosis can be
provided for an aortic valve bypass procedure. Thereafter, graft
conduit 20 can be connected, in ways well known in the art, to the
left ventricle of the heart as part of an aortic valve bypass
procedure.
[0058] It will be appreciated that, with this construction, ratchet
bracket 10 is instrumental in locking outer collar 25 down onto the
outer surface of the descending aorta while simultaneously
sandwiching the aortic wall between inner collar 15 and flange 105
of outer collar 25 (FIG. 2). In this respect it will also be
appreciated that outer collar 25 has two diametrically-opposed
ratchet teeth 115 (FIG. 7), while ratchet bracket 10 has two
corresponding diametrically-opposed sets of ratchet teeth 55, with
the two diametrically-opposed sets of ratchet teeth 55 being
aligned with each end of the inner collar oval's major axis (FIG.
5). With this arrangement, each end of outer collar 25 can be
locked into a number of positions relative to ratchet bracket 10
(and hence relative to inner collar 15), thereby accommodating for
variable aortic wall thicknesses. In this respect it will also be
appreciated that the general oval shape of hollow ovoid body 85 of
outer collar 25 and hollow ovoid body 30 of ratchet bracket 10
serves to automatically establish and maintain alignment between
the mating ratchet teeth 55, 115 of the ratchet bracket and the
outer collar. In other words, relative rotation between the outer
collar and ratchet bracket is effectively prevented.
[0059] It will also be appreciated that, on account of the
foregoing construction, locked collar connector 5 presents only
graft material to the lumen of the anastomosis site.
Delivery Instrument
[0060] A novel delivery instrument 200 (FIGS. 8-12) is provided to
enable the physician to easily install and deploy locked collar
connector 5 through a small thoracotomy into a slit in the
descending aorta, whereby to form the desired distal anastomosis
for the aortic valve bypass.
[0061] Looking now at FIGS. 8-12, delivery instrument 200 generally
comprises a hollow ovoid column 205 (FIG. 9) having a pair of
traction arms 210 movably mounted to the distal end thereof. More
particularly, each of the traction arms 210 is pivotally mounted to
hollow ovoid column 205 via a pivot pin 220, whereby a toe 225
thereof may be moved radially inwardly or outwardly relative to the
longitudinal axis 230 of hollow ovoid column 205. A garter spring
235 is provided so as to urge toes 225 of traction arms 210
radially inwardly. A pair of handles 240 (FIG. 8) are attached to
hollow ovoid column 205.
[0062] Still looking at FIGS. 8-12, a clothespin rod 245, having a
bifurcated clothespin clamp 250 at its distal end, is movably
mounted within hollow ovoid column 205. As will hereinafter be
discussed, clothespin clamp 250 may be used to keep inner collar 15
of locking collar connector 5 folded along its long axis. When
clothespin rod 245 is in its extended position (FIG. 9), clothespin
rod 245 forces traction arms 210 apart, whereby to radially project
toes 225, in the manner shown in FIG. 9. In this way, and as will
hereinafter be discussed, toes 225 can be used to support the
undersides of L-shaped support arms 50 of inner collar 15, whereby
to grasp inner collar 15 to delivery instrument 200. When
clothespin rod 245 is in its retracted position (FIG. 15), garter
spring 235 urges toes 225 radially inwardly, in the manner shown in
FIG. 15. In this way, and as will hereinafter be discussed, toes
225 can be withdrawn from the undersides of L-shaped support arms
50 of inner collar 15, whereby to release inner collar 15 from
delivery instrument 200.
[0063] Still looking at FIGS. 8-12, a pair of collar actuators 255
are movably disposed about the exterior of hollow column 205. More
particularly, collar actuators 255 include a pair of slots 260
through which handles 240 project. By gripping handles 240 and
pressing on the proximal ends of collar actuators 255, the distal
ends of collar actuators 255 can be moved distally, whereby to
force outer collar 25 distally, as will hereinafter be discussed.
Collar actuators 255 together have an ovoid configuration.
[0064] To install locking collar connector 5 onto delivery
instrument 200, collar actuators 255 are moved proximally on hollow
ovoid column 205, and clothespin rod 245 is moved proximally within
hollow ovoid column 205 so that toes 225 are retracted inboard.
Next, outer collar 25 of locking collar connector 5 is slid onto
the distal end of hollow ovoid column 25. Then the single integral
assembly 27 of ratchet bracket 10, inner collar 15 and graft
conduit 20 is slid onto the distal end of hollow ovoid column 205.
Next, inner collar 15 is folded along the major axis of the oval.
Then clothespin rod 245 is moved distally so that toes 225 project
radially outward so as to support the underside of ratchet bracket
10 and so that clothespin clamp 250 holds portions of the Nitinol
oval of the inner collar 15 in close proximity across the oval's
minor axis. See FIGS. 8-12. Thus, the single integral assembly 27
of ratchet bracket 10, inner collar 15 and graft conduit 20 is
securely held in place on the distal end of delivery instrument
200, with graft conduit 20 trapped in the annular gap between
hollow ovoid column 205 and collar actuators 255, and with outer
collar 25 of locking collar connector 5 disposed on hollow ovoid
column 205 proximal to the aforementioned single integral assembly
27 (of ratchet bracket 10, inner collar 15 and graft conduit 20)
and distal to collar actuators 255.
[0065] Note that a portion of graft conduit 20 is folded under, and
is also held by, clothespin clamp 250. See FIGS. 10 and 13.
[0066] When locking collar connector 5 is to be deployed off the
distal end of delivery instrument 200, collar actuators 255 are
advanced distally while hollow ovoid column 205 is held stationary
(e.g., via handles 240). This causes outer collar 25 of locking
collar connector 5 to move distally, with flange 205 of outer
collar 205 moving toward inner collar 15 so as to clamp vascular
tissue therebetween, and with ratchet teeth 115 of outer collar 25
engaging ratchet teeth 55 of ratchet bracket 10 so as to lock the
two members in position relative to one another, and with graft
conduit 20 in fluid communication with the desired blood flow. With
locking collar connector 5 in position, clothespin rod 245 is
retracted proximally, releasing inner collar 15 from clothespin
clamp 250 (whereupon inner collar 15 springs back to its unfolded
condition) and allowing toes 225 to retract inwardly, whereby to
free delivery instrument 200 from locking collar connector 5.
Delivery instrument 200 may thereupon be withdrawn from the
surgical site, leaving locking collar connector 5 in position. In
this way, the distal anastomosis can be provided for an aortic
valve bypass procedure. Thereafter, graft conduit 20 can be
connected, in ways well known in the art, to the left ventricle of
the heart as part of an aortic valve bypass procedure.
Installation Method
[0067] The preferred method for installing locking collar connector
5 into the descending aorta using delivery instrument 200 is
detailed in the steps below.
[0068] 1. Access to the descending aorta is created through a small
thoracotomy, a thoracoscopy, or other minimally invasive opening in
the thoracic cavity.
[0069] 2. Two balloon catheters (Cook Coda.RTM. G36042, for
example) are fed up from the groin through one or both femoral
arteries. A first balloon ("the proximal balloon") is inflated
above the anastomosis site (proximal to the heart), and the second
balloon is inflated distal to the anastomosis site ("the distal
balloon"). See FIG. 13. Blood flow through the aorta is effectively
blocked by the two inflated balloons.
[0070] 3. The physician cuts a longitudinal slit at the anastomosis
site (FIG. 13).
[0071] 4. Delivery instrument 200, with locking collar connector 5
carried thereon, is advanced through the thoracotomy to the
anastomosis site. The delivery instrument is rotated so that the
major axis of inner collar 15 of locking collar connector 5 is
aligned with the aortic slit (FIG. 13). Then inner collar 15 is
inserted into the interior of the descending aorta via the aortic
slit. In this respect it will be appreciated that insertion of the
inner collar through the aortic slit and into the lumen of the
descending aorta can be aided by "picking up" the descending aorta
adjacent to the slit with a suitable pair of forceps (FIG. 13), and
the folded inner collar presents a narrow profile that can be fed
one end at a time into the aortic slit. The process is repeated at
the other end of the aortic slit until inner collar 15 is fully
positioned within the lumen of the descending aorta.
[0072] 5. Once inner collar 15 of locking collar connector 5 is
within the lumen of the descending aorta and substantially centered
on the aortic slit, the physician applies traction to the inner
collar via handles 240 (FIG. 8). As noted above, the handles are
rigidly connected to hollow ovoid column 205, which contains the
pivot axes for traction arms 210. The traction arms are in contact
with the ratchet bracket's L-shaped support arms 50 through a layer
of graft. With traction applied to inner collar 15 using the
handles as described above, the physician advances outer collar 25
down onto ratchet bracket 10 (FIG. 14). To this end, delivery
instrument 200 has a pair of collar actuators 255 (FIG. 9) that may
be moved independently of one another. The physician is able to
push on either, or both, collar actuators as required so as to set
outer collar 25. This provides tactile feedback to the physician
and enables him to properly compress each end of the outer collar
onto the ratchet bracket. The aortic wall is thus securely clamped
between outer collar 25 and the portion of the inner collar 15 near
the major axis of the Nitinol oval of the inner collar. As this
occurs, ratchet teeth 115 of outer collar 25 and ratchet teeth 55
of ratchet bracket 10 engage with each other so as to prevent the
inner collar and the outer collar from separating. See FIG. 14.
[0073] 6. The physician retracts clothespin rod 245, pulling
clothespin clamp 250 off the folded inner collar 15. As a result,
the inner collar springs outward until the inner wall of the
descending aorta is encountered. There is sufficient spring force
in the inner collar to create at least line-to-line contact along
the entire inner circumference of the aortic slit, thereby
establishing hemostasis. As clothespin rod 245 is further
retracted, the two traction arms 210 pivot towards each other,
moving toes 225 inboard and thereby releasing support arms 50 from
the delivery instrument. This action is preferably aided by the
provision of garter spring 235. See FIG. 15.
[0074] 7. Collar actuators 255 and hollow ovoid column 205 are
withdrawn. The graft conduit slips out from the annular gap between
the hollow ovoid column and the collar actuators.
[0075] 8. Means to block the neck of graft conduit 20, and maintain
hemostasis, are provided. By way of example but not limitation, a
cross-clamp on the graft conduit is one such simple approach. After
the graft conduit has been blocked and hemostasis is ensured, the
distal balloon is deflated and withdrawn. Then the proximal balloon
is deflated and withdrawn, leaving locking collar connector 5
deployed within the descending aorta.
[0076] 9. At this point, the distal anastomosis for the aortic
valve bypass procedure is complete. Graft conduit 20 can thereafter
be connected, in ways well known in the art, to the left ventricle
of the heart as part of an aortic valve bypass procedure.
Alternative Constructions for the Locking Collar Connector
[0077] An alternative embodiment of the locking collar connector is
shown schematically in FIG. 16, and includes:
[0078] 1. A prosthetic valve 300 is pre-installed in the proximal
end of graft conduit 20.
[0079] 2. A side branch 305 is provided on graft conduit 20. This
construction is useful when a valve is pre-installed in the graft
conduit. In this form of the invention, side branch 305 is
installed on the delivery instrument (see below), and graft conduit
20 hangs off to the side of the delivery instrument. Side branch
305 is preferably sized to fit in the annular gap between the
hollow ovoid column and the collar actuators.
[0080] 3. A connector 310 is provided for attaching the proximal
end of graft conduit 20 to another conduit. This connector may be
(i) a male-female slip connector such as is taught in FIG. 15 of
U.S. Pat. No. 7,510,561, issued Mar. 31, 2009 to Richard M. Beane
et al. for APPARATUS AND METHOD FOR CONNECTING A CONDUIT TO A
HOLLOW ORGAN (Attorney's Docket No. CORREX-033058-000005), which
patent is hereby incorporated herein by reference, and/or (ii) a
snap-together coupling of the sort known in the fluid-coupling art,
with self-sealing capability on at least one side of the
coupling.
[0081] Inner collar 15 may also be constructed out of a stacked set
of thin oval steel washers, rather than out of a single Nitinol
sheet 0.009'' thick. By way of example but not limitation, a set of
(4) 0.002'' thick stainless steel ovals can be stacked and joined
together when the ratchet bracket is over-molded. Acting in tandem,
this stack of stainless steel oval sheets can provide suitable
flexibility and spring force with a low attendant stress level.
[0082] Consequently, the risk of a fatigue failure can be
significantly reduced.
Variation to the Foregoing Installation Method
[0083] Where a side branch 305 is present on graft conduit 20, the
side branch can be held within the delivery instrument instead of
the graft conduit. Installation then proceeds as outlined above.
One advantage of this alternative configuration and approach is
that a prosthetic valve 300 can be pre-installed within the graft
conduit where a side branch is provided. The graft conduit, with
valve, then remains undisturbed throughout the distal
anastomosis.
Use of the Present Invention for Other Applications
[0084] As disclosed above, the present invention may be used for
effecting a distal anastomosis for an aortic valve bypass. However,
it should be appreciated that the present invention can also be
used for a distal anastomosis for any bypass procedure, or for
substantially any joinder of one vessel to another vessel.
Further Modifications
[0085] It will be understood that many additional changes in the
details, materials, steps and arrangements of parts, which have
been herein described and illustrated in order to explain the
nature of the invention, may be made by those skilled in the art
while remaining within the principles and scope of the present
invention.
* * * * *