U.S. patent application number 10/351954 was filed with the patent office on 2003-10-02 for medical anastomosis apparatus.
Invention is credited to Berg, Todd Allen, Galdonik, Jason A., Swanson, William J., Thome, Scott P., Wahlberg, Mark D..
Application Number | 20030187499 10/351954 |
Document ID | / |
Family ID | 22686241 |
Filed Date | 2003-10-02 |
United States Patent
Application |
20030187499 |
Kind Code |
A1 |
Swanson, William J. ; et
al. |
October 2, 2003 |
Medical anastomosis apparatus
Abstract
A connector for use in providing an anastomotic connection
between two tubular body fluid conduits in a patient. The connector
is preferably a single, integral, plastically deformable structure
that can be cut from a tube. The connector has axial spaced
portions that include members that are radially outwardly
deflectable from other portions of the connector. The connector is
annularly enlargeable so that it can be initially delivered and
installed in the patient in a relatively small annular size and
then annularly enlarged to provide the completed anastomosis. The
radially outwardly deflected members of the first and second
portions respectively engage the two body fluid conduits connected
at the anastomosis and hold those two conduits together in
fluid-tight engagement. Apparatus for use in delivering and
deploying a connector is also disclosed.
Inventors: |
Swanson, William J.; (St.
Paul, MN) ; Wahlberg, Mark D.; (St. Paul, MN)
; Galdonik, Jason A.; (St. Louis Park, MN) ; Berg,
Todd Allen; (Stillwater, MN) ; Thome, Scott P.;
(St. Cloud, MN) |
Correspondence
Address: |
FISH & NEAVE
1251 AVENUE OF THE AMERICAS
50TH FLOOR
NEW YORK
NY
10020-1105
US
|
Family ID: |
22686241 |
Appl. No.: |
10/351954 |
Filed: |
January 24, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10351954 |
Jan 24, 2003 |
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10078939 |
Feb 19, 2002 |
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6533812 |
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10078939 |
Feb 19, 2002 |
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09955231 |
Sep 17, 2001 |
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6440163 |
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09955231 |
Sep 17, 2001 |
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09527668 |
Mar 17, 2000 |
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6309416 |
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09527668 |
Mar 17, 2000 |
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09186774 |
Nov 6, 1998 |
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6113612 |
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Current U.S.
Class: |
623/1.23 |
Current CPC
Class: |
A61F 2220/0016 20130101;
A61B 2017/1139 20130101; A61F 2230/0054 20130101; A61B 17/064
20130101; A61F 2/88 20130101; A61F 2220/0008 20130101; A61B
2017/0641 20130101; A61B 2017/1135 20130101; A61F 2250/0067
20130101; A61F 2230/005 20130101; A61F 2220/0075 20130101; A61B
17/11 20130101 |
Class at
Publication: |
623/1.23 |
International
Class: |
A61F 002/06 |
Claims
The invention claimed is:
1. Apparatus for inserting an annular anastomotic connector into a
side wall of a tubular body tissue conduit comprising:
substantially conical tip structure having a cone angle less than
about 15.degree. and configured for passage through the side wall
starting with an apex of the cone; a shaft structure extending from
the tip structure in a direction away from the apex and configured
to receive the connector annularly around the shaft structure; an
inflatable annular balloon having a first cross-sectional radius at
the distal end, and a second cross-sectional radius at the proximal
end, wherein the second cross-sectional radius is greater than the
first cross-sectional radius, wherein the inflatable annular
balloon is configured for disposition annularly around the shaft
structure and inside the connector around the shaft structure,
wherein expansion of the balloon first causes deformation of distal
fingers of the connector and subsequently causes radial expansion
of the connector.
Description
[0001] This application is a continuation of U.S. patent
application Ser. No. 10/078,939, filed Feb. 19, 2002, which is a
continuation of U.S. patent application Ser. No. 09/955,231, filed
Sep. 17, 2001 (now U.S. Pat. No. 6,440,163), which is a division of
U.S. patent application Ser. No. 09/527,668, filed Mar. 17, 2000
(now U.S. Pat. No. 6,309,416), which is a division of U.S. patent
application Ser. No. 09/186,774, filed Nov. 6, 1998 (now U.S. Pat.
No. 6,113,612). All of these prior applications are hereby
incorporated by reference herein in their entireties.
BACKGROUND OF THE INVENTION
[0002] This invention relates to medical apparatus, and more
particularly to apparatus for use in making anastomotic connections
between tubular body fluid conduits in a patient.
[0003] There are many medical procedures in which it is necessary
to make an anastomotic connection between two tubular body fluid
conduits in a patient. An anastomotic connection (or anastomosis)
is a connection which allows body fluid flow between the lumens of
the two conduits that are connected, preferably without allowing
body fluid to leak out of the conduits at the location of the
connection. As just one example of a procedure in which an
anastomosis is needed, in order to bypass an obstruction in a
patient's coronary artery, a tubular graft supplied with aortic
blood may be connected via an anastomosis to the contrary artery
downstream from the obstruction. The anastomosis may be between the
end of the graft and an aperture in the side wall of the coronary
artery (a so-called end-to-side anastomosis), or the anastomosis
may be between an aperture in the side wall of the graft and an
aperture in the side wall of the coronary artery (a so-called
side-to-side anastomosis (e.g., as in published Patent Cooperation
Treaty ("PCT") patent application WO 98/16161, which is hereby
incorporated by reference herein in its entirety)). The graft may
be natural conduit, artificial conduit, or a combination of natural
and artificial conduits. If natural conduit is used, it may be
wholly or partly relocated from elsewhere in the patient (e.g.,
wholly relocated saphenous vein or partly relocated internal
mammary artery). Alternatively, no relocation of the graft may be
needed (e.g., as in above-mentioned application WO 98/16161 in
which a length of vein on the heart becomes a "graft" around an
obstruction in an immediately adjacent coronary artery). More than
one anastomosis may be needed. For example, a second anastomosis
may be needed between an upstream portion of the graft conduit and
the aorta or the coronary artery upstream from the obstruction in
that artery. Again, this second anastomosis may be either an
end-to-side anastomosis or (as shown, for example, in
above-mentioned application WO 98/16161) a side-to-side
anastomosis. Alternatively, no second, upstream anastomosis may be
required at all (e.g., if the graft is an only-partly-relocated
internal mammary artery).
[0004] The currently most common technique for making an
anastomosis is to manually suture the two tubular body fluid
conduits together around an opening between them. Manual suturing
is difficult and time-consuming, and the quality of the anastomosis
that results is highly dependent on the skill of the person doing
the suturing. In the case of coronary artery bypass procedures, one
source of difficulty for suturing of an anastomosis may be motion
of the heart. There is also increasing interest in procedures which
are less invasive or even minimally invasive. Such procedures have
potentially important advantages for patients, but they may
increase the difficulty of performing manual suturing of an
anastomosis by reducing or limiting access to the site within the
patient at which the anastomosis must be made. Various examples of
such less invasive or minimally invasive procedures are shown in
above-mentioned application WO 98/16161, Goldsteen et al. U.S. Pat.
No. 5,976,178, Sullivan et al. U.S. Pat. No. 6,120,432, published
PCT patent application Wo 98/55027, and Berg et al. U.S. Pat. No.
6,475,222, all of which are hereby incorporated by reference herein
in their entireties.
[0005] In view of the foregoing, it is an object of this invention
to provide apparatus that can be used to make anastomotic
connections in lieu of manual suturing.
[0006] It is another object of the invention to provide apparatus
that can be used to make anastomotic connections even though access
to the site of the anastomosis may be limited or even only indirect
or remote.
[0007] It is still another object of the invention to provide
apparatus that can be used to make anastomotic connections without
the need for a high degree of manual suturing skill.
[0008] It is yet another object of the invention to provide
apparatus for making anastomotic connections that is less adversely
affected than manual suturing by adjacent or nearby body motion
(e.g., motion of the patient's heart).
[0009] It is still another object of this invention to provide
apparatus for facilitating the making of higher quality anastomotic
connections more rapidly and with more consistent results than is
possible with prior art methods and apparatus such as manual
suturing.
SUMMARY OF THE INVENTION
[0010] These and other objects of the invention are accomplished in
accordance with the principles of the invention by providing a
connector for use in making an anastomotic connection between two
tubular body fluid conduits in a patient, the connector being of
substantially one-piece or unitary construction which extends
annularly about a central longitudinal axis. The structure of the
connector includes axially spaced first and second portions, at
least one of which includes members that are deflectable radially
out from a remainder of the connector structure. In some
embodiments both of the axially spaced first and second portions
include members that are deflectable radially out from a remainder
of the structure. The connector structure is annularly enlargeable,
preferably by inflation of a balloon placed temporarily inside the
connector. The structure of the connector preferably lends itself
to formation by removal of selected material from a single unitary
tube. The connector is typically made of metal which is plastically
deformable (e.g., in the above-mentioned radial outward deflections
and annular enlargement).
[0011] The members that are deflectable radially out from the first
portion of the connector structure are configured to engage the
side wall of one of the two tubular body fluid conduits that are to
be connected. The members that are deflectable radially out from
the second portion of the connector structure are configured to
engage the side wall of the other of the two body fluid conduits
that are to be connected. Alternatively, one of the two portions of
the connector can be secured (preferably pre-secured) to the
associated conduit by other means such as sutures. Annular
expansion of the connector preferably causes the first and second
portions of the connector structure to move toward one another
along the central longitudinal axis of the connector, thereby
causing the connector to draw the two tubular body fluid conduits
together at the anastomosis between them. This helps produce an
anastomosis which is fluid-tight (i.e., from which body fluid does
not leak).
[0012] The connectors of this invention can be used to provide
either end-to-side or side-to-side anastomoses. The connector may
be first attached to one of the body fluid conduits to be connected
(e.g., an end portion of a graft conduit), and then delivered along
with the attached end of the first conduit to the connection point
with the second conduit, where the connector is fully deployed to
produce an anastomosis between the first and second conduits. Prior
to full deployment the connector preferably has a relatively small
circumference, which facilitates delivery and initial installation
in the patient, even at relatively remote or inaccessible locations
in the patient. For example, the connector can be delivered via
lumens of body fluid conduits in the patient and/or relatively
small-diameter instrumentation such as a cannula or
laparascopic-type device. Final installation can be performed
substantially solely by inflation of a balloon temporarily disposed
in the connector. No direct manipulation of the connector may be
needed. All of these attributes facilitate use of the connector at
remote or inaccessible locations in the patient. The connector
therefore lends itself to use in less invasive or minimally
invasive procedures.
[0013] Instrumentation for facilitating installation of the
connector through the side wall of a body fluid conduit is also
disclosed. This instrumentation has a gradually tapered distal nose
portion with an outer surface that is free of features that could
snag on the side wall of the body fluid conduit to be penetrated by
the nose portion. At least the portion of the connector that must
pass through the body fluid conduit side wall is completely covered
by the instrumentation until that portion of the connector is
through the side wall. These features of the instrumentation help
it penetrate the body fluid conduit side wall with no snagging and
with minimal trauma. Thereafter the distal nose portion can be
shifted distally relative to the connector to expose the connector
in position through the side wall. Other parts of the
instrumentation (e.g., an inflatable balloon) can then be operated
to complete the deployment of the connector.
[0014] Further features of the invention, its nature and various
advantages will be more apparent from the accompanying drawings and
the following detailed description of the preferred
embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a simplified planar development of the structure
of an illustrative embodiment of a connector constructed in
accordance with this invention.
[0016] FIG. 2 is a simplified perspective view of the actual
structure of the connector which is shown in planar development in
FIG. 1.
[0017] FIG. 3 is a simplified elevational view of the FIG. 2
structure after some further processing in accordance with the
invention.
[0018] FIG. 4 is a simplified planar development of the structure
of FIGS. 1-3 showing that structure's capacity for annular
enlargement in accordance with the invention.
[0019] FIG. 5 is a simplified elevational view of the structure of
FIG. 3 with some additional structure in accordance with the
invention.
[0020] FIG. 6 is a simplified elevational view, partly in section,
of the structure of FIG. 5 with still more additional structure in
accordance with the invention.
[0021] FIG. 7 is a simplified sectional view of the structure of
FIG. 6 with additional illustrative apparatus shown for use in
delivering and deploying the FIG. 6 structure in a patient in
accordance with the invention.
[0022] FIG. 8 is a simplified elevational view, partly in section,
showing an early stage in use of the FIG. 7 apparatus in accordance
with the invention.
[0023] FIG. 9 is a view similar to FIG. 8, but with more elements
shown in section, and showing a later stage in use of the FIG. 7
apparatus in accordance with the invention.
[0024] FIG. 10 is a view similar to FIG. 9 showing a still later
stage in use of the FIG. 7 apparatus in accordance with the
invention.
[0025] FIG. 11 is a view similar to FIG. 10 showing the end result
of using the FIG. 7 apparatus in accordance with the invention.
[0026] FIG. 12 is a view similar to FIG. 1 for another illustrative
embodiment of a connector constructed in accordance with the
invention.
[0027] FIG. 13 is a view similar to FIG. 4, but for the embodiment
of FIG. 12.
[0028] FIG. 14 is a simplified perspective view showing the
connector of FIG. 12 with other elements in accordance with the
invention.
[0029] FIG. 15 is another simplified perspective of a later stage
in use of some of the elements shown in FIG. 14.
[0030] FIG. 16 is another simplified perspective view, partly in
section, of a still later stage in use of the elements shown in
FIG. 15.
[0031] FIG. 17 is another view, generally similar to FIG. 16,
showing an even later stage in use of the elements shown in FIG.
16.
[0032] FIG. 18 is a simplified perspective view of a completed
anastomosis including the connector of FIG. 12.
[0033] FIG. 19 is another view, partly in section, of the
anastomosis of FIG. 18.
[0034] FIG. 20 is a simplified perspective view of an illustrative
embodiment of a starting structure for use in making connectors in
accordance with the invention.
[0035] FIG. 21 is a simplified elevational view, partly in section,
illustrating a possible modification of connectors in accordance
with the invention.
[0036] FIG. 22 is a simplified elevational view, partly in section,
illustrating another possible modification of connectors in
accordance with the invention.
[0037] FIG. 23 is a simplified sectional view of an alternative
finished anastomosis in accordance with the invention.
[0038] FIG. 24 is a view similar to FIG. 4 for still another
illustrative embodiment of a connector constructed in accordance
with the invention.
[0039] FIG. 25 is a view similar to FIG. 11 for a completed
anastomosis employing a connector of the type shown in FIG. 24.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0040] FIG. 1 shows a planar development of what is actually an
integral, one-piece (unitary), annular structure 10. In particular,
the left and right edges of the structure shown in FIG. 1 are
actually joined to and integral with one another. Thus the actual
structure is as shown in FIG. 2, although FIG. 1 is useful to more
clearly reveal the details of various features of the structure. A
central longitudinal axis 12 about which structure 10 is annular is
shown in FIG. 2.
[0041] An illustrative material for structure 10 is 304 stainless
steel. Other examples of suitable materials include tantalum,
tungsten, platinum, and nitinol. Structure 10 may be advantageously
produced by starting with a single, unitary metal tube and removing
selected material until only the structure shown in FIG. 2 remains.
For example, laser cutting may be used to remove material from the
starting tube in order to produce structure 10. Although connectors
10 can be made in various sizes for various uses, a typical
connector has an initial outside diameter in the range from about
0.040 to about 0.065 inches, an initial length of about 4.0 mm, and
a material thickness of about 0.004 inches.
[0042] Connector 10 may be described as including axially spaced
first and second portions 20 and 40, respectively. First portion 20
includes a plurality of annularly spaced members 22 that in this
case have free end portions 24 that are sharply pointed and that
point toward second portion 40. Each of members 22 is deflectable
radially out from the remainder of structure 10 as shown, for
example, in FIG. 3. This outward deflection is preferably at least
partly plastic.
[0043] Second portion 40 also includes a plurality of annularly
spaced members 42 that in this case have free end portions 44 that
are sharply pointed and that point toward first portion 20. Each of
members 42 is deflectable radially out from the remainder of
structure 10 as shown, for example, in FIG. 3. Again, this outward
deflection is preferably at least partly plastic.
[0044] The above-mentioned outward deflection of elements 22 and 42
can be produced by putting the connector on a mandrel and prying
elements 22 and 42 radially outward.
[0045] Connector 10 is formed in such a way that it is annularly
enlargeable (e.g., by inflation of a balloon that is temporarily
disposed inside the connector). The annularly expanded condition of
connector 10 is shown in FIGS. 4, 10, and 11. The annular
expandability of connector 10 is provided by making the connector
with a plurality of annularly adjacent, annularly enlargeable
cells. For example, a typical cell includes annularly spaced, but
adjacent, longitudinal members 50a and 52a. The axially spaced ends
of this pair of members are connected to one another at 54a and
56a. The next annularly adjacent similar cell includes elements
50b, 52b, 54b, and 56b. Annularly adjacent ones of these cells are
connected to one another (e.g., as at 66a) at locations which are
axially medial to their axial end connections 54 and 56. In this
way structure 10 is annularly enlargeable by annularly enlarging
each of the above-mentioned cells (see FIG. 4).
[0046] In addition to the cells that are described above, structure
10 includes other, similarly annularly expandable cells that are
axially and annularly offset from the first-described cells. A
representative one of these other cells includes annularly adjacent
longitudinal members 60a and 62a, the axially spaced ends of which
are connected at 64a and 66a. (It should be noted that part of
member 60a is common with part of member 52a, and part of member
62a is common with part of member 50b.) The next annularly adjacent
cell of this kind includes components 60b, 62b, 64b, and 66b.
Annularly adjacent cells of this kind are connected to one another
at locations like 54b, which are axially medial the axial endpoints
64 and 66 of those cells. Thus again the structure is annularly
enlargeable by annularly enlarging these cells as shown, for
example in FIG. 4.
[0047] It will be appreciated that as structure 10 annularly
enlarges, it generally axially shortens. In other words, as cells
50/52/54/56 and 60/62/64/66 widen in the annular direction, they
shorten in the axial direction. Thus annular enlargement of
structure 10 decreases the axial spacing between portions 20 and
40, and more particularly decreases the axial spacing between
member 22, on the one hand, and members 42, on the other hand.
[0048] A typical use of connector 10 is, in a coronary artery
bypass procedure, to provide an anastomosis between an axial end
portion of a tubular graft conduit and an aperture in a side wall
of a coronary artery. For this kind of use connector 10 may be
loaded on an uninflated balloon 110 near the distal end of a
balloon catheter 100 as shown in FIG. 5. In other words, connector
10 and catheter 100 are assembled so that connector 10 extends
annularly around uninflated balloon 110.
[0049] Graft conduit 120 is then placed annularly around the first
portion 20 of connector 10 and the adjacent portion of catheter 100
as shown in FIG. 6. Graft conduit may be natural body tissue (e.g.,
a length of the patient's saphenous vein harvested for use as a
graft, a partly severed internal mammary artery, etc.), an
artificial graft (e.g., as shown in Goldsteen et al. U.S. Pat. No.
5,976,178, or published PCT patent application WO 98/19632, both of
which are hereby incorporated by reference herein in their
entireties), or a combination of natural and artificial conduits
(e.g., a length of natural conduit disposed substantially
concentrically inside a length of artificial conduit). Graft
conduit 120 is placed on assembly 10/100 so that radially outwardly
deflected members 22 penetrate and pass through the side wall of
the graft conduit (e.g., as a result of compressing the graft
against the fingers, thereby forcing the fingers to pierce through
the graft wall). The sharpened free ends of members 22 facilitate
penetration of conduit 120 by members 22. The blunt rear surfaces
of enlarged free end portions 24 resist withdrawal of members 22
from conduit 120 after members 22 have penetrated the conduit. The
graft may be additionally or alternatively directly sutured to the
connector body. If the alternative of suturing graft 120 to the
connector is used, then the first portion 20 of the connector may
not need radially outwardly deflectable members 22 for engagement
of the graft conduit.
[0050] As an alternative to securing graft 120 to connector 10
after balloon 110 has been associated with the connector, balloon
110 may be installed in connector 10 after the graft has been
secured to the connector.
[0051] Illustrative apparatus 200 for delivering connector 10 and
graft 120 to a location in a patient requiring a graft and an
anastomosis, and for then deploying the connector and graft, is
shown in FIG. 7. Apparatus 200 includes an optional guide wire 210,
which may be first installed in the patient along the route that
the remainder of the apparatus is later to follow to reach the
desired location in the patient. The remainder of the apparatus is
then slid into the patient along guide wire 210. Alternatively,
guide wire 210 may be omitted, or a leading guide member (e.g., a
wire) may be fixedly mounted on the distal (leftward in FIG. 2) end
of the remainder of the apparatus. The wire allows precise tracking
of the nose cone 220 and delivery system 200 into a patient's body
fluid conduit (e.g., a coronary artery 300 as shown in FIGS. 8-10
and described below).
[0052] Apparatus 200 includes a gradually tapered distal nose
portion or dilator 220 which extends annularly around a central,
longitudinally extending, guide wire lumen 222. Distal nose portion
220 has a substantially conical outer surface with a cone angle A,
which is preferably less than about 15.degree. (e.g., in the range
from about 5.degree. to about 15.degree., more preferably in the
range from about 5.degree. to about 10.degree.). Such gradual
tapering of nose portion 220 is desirable to enable nose portion to
gradually enlarge an aperture in a side wall of a body fluid
conduit to which graft 120 is to be connected without snagging on
that conduit side wall. This geometry allows optimal passage across
a body conduit wall (e.g., a coronary artery wall as shown in FIG.
8 and described below) with minimal wall damage, with minimal force
being required, and with no catching or snagging on the wall.
Distal nose portion 220 may have cutting edges to further
facilitate entry through a body fluid conduit side wall.
[0053] Distal nose portion 220 is connected to tube 230, which
extends proximally from the nose portion annularly around guide
wire 210. Thus the lumen of tube 230 constitutes a proximal
continuation of guide wire lumen 222. Tube 230 may be made of
stainless steel hypotube, which allows the depicted apparatus to be
pushed or pulled axially along guide wire 210.
[0054] A proximal portion of distal nose portion 220 is hollowed
out as indicated at 224 to receive balloon 110, connector 10, and a
distal portion of graft 120 substantially coaxially around a medial
portion of tube 230. For this arrangement balloon 110 is provided
as a hollow annulus at or near the distal end of hollow tubular
member 100. The side wall of tube 100 may include a separate lumen
(not shown but conventional for balloon catheters) through which
pressurized inflation fluid may be supplied from a proximal region
of the apparatus to balloon 110. Elements 100 and 110 are slidable
axially along the outer surface of tube 230. Insertion of elements
10, 110, and 120 (FIG. 6) into the annular recess 224 in distal
nose portion 220 deflects the radially outermost portions of
members 22 back over graft 120 as shown in FIG. 7. Tube 240,
disposed substantially coaxially around element 100 inside graft
120 so that its distal end bears against members 22, may be used to
help load elements 10, 110, and 120 into recess 224, and also to
hold connector 10 in place in recess 224 during delivery of the
connector to the anastomosis site in the patient.
[0055] FIG. 8 shows a typical use of apparatus 200 to deliver graft
120 for connection to an aperture in a side wall of a patient's
tubular body conduit 300 (e.g., a coronary artery requiring a
bypass graft). Guide wire 210 is first installed through a small
aperture in the side wall of the conduit. The natural elastic
recoil of the conduit 300 side wall seals the aperture around the
guide wire so that there is little or no body fluid (e.g., blood)
leakage out of the conduit via the aperture. The tapered distal
nose portion 220 of apparatus 200 is then gradually forced into the
aperture (e.g., by using tube 230 to push portion 220 distally into
the aperture) to dilate the aperture. The natural elastic recoil of
the conduit 300 side wall tissue continues to keep the aperture
sealed or substantially sealed around portion 220.
[0056] When distal nose portion 220 has been pushed far enough into
the aperture in the side wall of conduit 300 so that connector 10
is part way through the aperture, further distal motion of elements
10, 100, 110, and 120 can be stopped (e.g., by holding a proximal
portion of element 100 stationary). Tube 240 is then pulled
proximally out of the patient. Thereafter, distal nose portion 220
is pushed farther into conduit 300 (e.g., by continuing to push
distally on a proximal portion of element 230). This causes distal
nose portion 220 to separate from connector 10, thereby exposing
the connector and leaving it in the aperture through the conduit
300 side wall as shown in FIG. 9.
[0057] The next step in use of apparatus 200 is to inflate balloon
110 as shown in FIG. 10. The balloon is typically sized to a
specific anastomosis size (e.g., 3 millimeters diameter, 4
millimeters diameter, etc.). Inflation of the balloon forces
connector 10 to annularly enlarge by enlarging cells 50/52/54/56
and 60/62/64/66 in the annular direction. In addition, the portions
of members 60 and 62 that are adjacent to elements 64 (as well as
elements 64 and 42) are deflected radially out beyond other
portions of the connector inside the side wall of conduit 300,
thereby causing the extreme distal end of graft 120 to similarly
flare out inside that side wall. This outward flaring of portions
of connector 10 and graft 120 helps secure the connector and graft
to the side wall of conduit 300, and also helps seal the graft to
the conduit. The axial shortening of connector 10 that accompanies
annular enlargement ensures that graft 120 is drawn into secure and
fluid-tight engagement with conduit 300. The free ends of members
42 preferably penetrate the side wall of conduit 300 to further
secure connector 10 and graft 120 in the aperture in the side wall.
Members 50, 52, 56, and 24 may also flare out somewhat outside the
side wall of graft 300 to help ensure that graft 120 remains open
where it connects to conduit 300. Assuming that the connector is
approximately properly positioned relative to the side wall of
conduit 300 prior to inflation of balloon 110, the connector is
effectively self-centering on the conduit 300 side wall as the
balloon is inflated.
[0058] The next step in use of apparatus 200 is to deflate balloon
110 and withdraw all of elements 100, 110, 210, 220, and 230 (e.g.,
by pulling them proximally out of graft 120). This leaves the axial
end portion of graft 120 connected to the side wall of conduit 300
by annularly enlarged connector 10 as shown in FIG. 11. In
particular, in this example connector 10 provides an end-to-side
anastomosis between graft 120 and conduit 300. Body fluid from
graft 120 is able to flow into conduit 300 via this connection.
Connector 10 presses graft 120 radially outward against the
aperture through the side wall of conduit 300 all the way around
that aperture, thereby preventing body fluid from leaking out of
conduits 120 and 300. Connector 10 also prevents the end of conduit
120 from pulling out of the side wall of conduit 300.
[0059] Another illustrative embodiment of a connector 410 in
accordance with this invention is shown (in simplified planar
development) in FIG. 12. Again, although connector 410 can be made
in various sizes for various uses, a typical initial length of
connector 410 is about 4.0 mm, and a typical initial outside
diameter is in the range from about 0.040 to about 0.065 inches. A
typical shaft length for members 422 is about 0.0539 inches, and a
typical shaft width for those members is about 0.0050 inches. As in
the case of connector 10, connector 410 may be cut from a single
integral tube. A typical thickness for the material of connector
410 is about 0.004 inches. Suitable materials for connector 410
include stainless steel, tantalum, tungsten, platinum, and
nitinol.
[0060] Connector 410 may be described as including axially spaced
first and second portions 420 and 440, respectively. First portion
420 includes a plurality of annularly spaced first members 422
having free end portions 424 that initially point axially away from
second portion 440. However, members 422 are deflectable radially
out from other parts of the connector, and, if desired, free end
portions 424 can be curved back so that they point toward second
portion 440 (see FIG. 15).
[0061] The first portion 420 of connector 410 may also be said to
include the lower portions (below members 454) of cells, each of
which includes one member 460, one member 462, one member 464, and
one member 466. For example, the left-most cell shown in FIG. 12
includes substantially parallel members 460a and 462a joined at
their axially spaced ends by members 464a and 466a. Annularly
adjacent cells are joined by members 454 at points that are axially
medial their axial ends. For example, the cell that includes member
462a is joined to the cell that includes member 460b by members
454b. The portions of members 460 and 462 below members 454 are
also deflectable radially out from other portions of the
connector.
[0062] The second portion 440 of connector 410 may be said to
include the portions of members 460 and 462 above members 454.
These portions of members 460 and 462 are also deflectable radially
out (as loops 460/462/464) from other portions of the connector. If
desired, loops 460/462/464 could also have fingers or barbs on them
like members 42 in the embodiment of FIGS. 1-11.
[0063] Connector 410 is annularly enlargeable by deforming members
460 and 462 to enlarge each of the above-described cells in the
annular direction as shown in greatly simplified form in FIG.
13.
[0064] FIG. 14 shows an illustrative embodiment of tooling 500 that
can be used to facilitate attachment of a graft conduit 120 to
connector 410. Tooling 500 includes a mandrel with a conical end
portion, the pointed free end of which is small enough to fit
axially into connector 410 in its initial relatively small annular
size. As connector 410 is forced farther onto the conical end
portion of mandrel 500, the cone of the mandrel begins to deflect
members 422 radially out from other portions of the connector.
Graft conduit 120 can be placed around mandrel 500 and shifted
axially toward connector 410 until an axial end portion of conduit
120 axially overlaps outwardly deflected members 422. The free end
portions of members 422 can then be pried out through the side wall
of conduit 120 as shown in FIG. 15 to secure connector 410 to
conduit 120. Mandrel 500 can be pulled proximally out of graft 120
and connector 410 at any suitable time. Use of mandrel 500 in this
way helps ensure that members 422 penetrate the side wall of
conduit 120 substantially equidistantly in the annular direction
around the conduit. This helps avoid excessive stretching of any
angular segment of graft 120 when connector 410 is subsequently
expanded by balloon 110.
[0065] After connector 410 has been attached to graft 120 as shown
in FIG. 15, an inflatable balloon like balloon 110 (with tube 100)
can be inserted into the connector in a manner similar to what is
shown in FIG. 6. Elements 100, 110, 120, and 410 can then be loaded
into apparatus like 200 in a manner similar to what is shown in
FIG. 7 (except that in this case the free ends 424 of members 422
will typically point in the distal direction rather than in the
proximal direction as is true for the free ends 24 of members 22 in
FIG. 7). Apparatus 200 can then be used to install connector 410
and graft 120 in a patient in a manner similar to the installation
shown in FIGS. 8-11. FIG. 16 shows the second portion 440 after it
has been conveyed through the side wall of conduit 300 by apparatus
200 and apparatus 200 has been shifted distally farther into
conduit 300 to expose the connector. FIG. 17 shows second portion
loops 460/462/464 deployed (radially outwardly deflected), but the
remainder of the connector not yet annularly expanded. A shaped
balloon or dual balloon system may be utilized to achieve this. For
example, one of two axially adjacent balloons may be used to help
form distal retention fingers 460/462/464 as shown in FIG. 17. The
second of the two balloons is thereafter used to annularly expand
the remainder of the connector and the anastomosis opening.
Alternatively, a single "bulbous" shaped balloon may be used to
produce a temporary intermediate condition like that shown in FIG.
17, and to then annularly enlarge the remainder of the connector
and the anastomosis opening. As still another possibility the
distal retention fingers 460/462/464 may be self-actuating (i.e.,
spring-biased) and not require balloon assist to spring out to the
condition shown in FIG. 17. For example, distal retention fingers
460/462/464 may be preformed to deflect radially outward in a
manner similar to the radially outward preform that is given to
elements 22 and 42 in FIG. 3.
[0066] The final anastomosis employing connector 410 is shown in
FIGS. 18 and 19. In particular, as shown in FIGS. 18 and 19
connector 410 has been annularly expanded by enlargement of the
cells 460/462/464/466 in the annular direction. The portions of
members 460 and 462 that comprise portion 440 of the connector have
been deflected radially out from other portions of the connector
inside conduit 300, thereby functioning to secure connector 410 and
graft 120 to conduit 300. Members 422 are deflected radially out
from other portions of the connector and pass through the axial end
portion of graft 120. The free end portions of members 422 point
toward the second portion 440 of the connector, thereby ensuring
that the end of graft 120 cannot slip away from its
body-fluid-sealing abutment with the side wall of conduit 300. The
annularly expanded medial portion of connector 410 holds open the
aperture in the side wall of conduit 300, as well as the attached
end of graft 120, thereby ensuring unobstructed body fluid flow
through the anastomosis between conduits 120 and 300.
[0067] Still another illustrative embodiment of a connector 610 in
accordance with this invention is shown in greatly simplified,
annularly expanded, planar development in FIG. 24. Connector 610 is
configured for use in performing a side-to-side anastomosis between
two body fluid conduits 300a and 300b as shown in FIG. 25.
Connector 610 has a construction like two portions 40 of connector
10 connected together. Thus members 642a and 642b are constructed
and operate like members 42 in connector 10. Similarly, members 660
are constructed and operate generally like members 60 and 62 in
connector 10, and elements 664 and 666 are constructed and operate
generally like elements 64 and 66, respectively, in connector
10.
[0068] Connector 610, in an initially relatively small annular size
and mounted on a balloon, is insertable through adjacent apertures
in the side walls of body fluid conduits 300a and 300b. For
example, apparatus like 200 can be used to deliver connector 610 to
such a site via the lumen of one of conduits 300 and to then
position the connector so that it spans both conduits. Apparatus
200 is then shifted relative to connector 610 in a manner generally
similar to FIG. 9 to expose the connector. The balloon 110
associated with the connector is then inflated to annularly enlarge
the connector to the condition shown in FIG. 25. In particular,
this annular expansion causes members 642a to penetrate the side
wall of conduit 300a annularly around the anastomotic opening, and
also causes members 642b to penetrate the side wall of conduit 300b
annularly around the anastomotic opening. As with the other
connectors of this invention, annular enlargement of connector 610
is accompanied by axial shortening, which helps to draw the side
walls of conduits 300a and 300b together annularly around the
connector, thereby providing the desired fluid-tight anastomosis
between the conduits. When the anastomosis is thus complete, the
balloon inside the connector is deflated and all the apparatus is
withdrawn through the anastomosis.
[0069] It will be understood that the foregoing is only
illustrative of the principles of this invention, and that various
modifications can be made by those skilled in the art without
departing from the scope and spirit of the invention. For example,
the number and shape of the annularly enlargeable connector cells
can be different from what is shown in the drawings herein. The
number of axially adjacent rows of annularly enlargeable cells can
be different from the numbers of such rows that are shown herein
(i.e., two rows of cells in the case of connectors 10 and 610 or
one row of cells in the case of connector 410). For example, a
connector may have three, four, or more rows of cells. The cells
may have any of many forms, depending on the desired degree of
expansion and final radial strength. The number of cells, the
number of rows of cells, the size of the cells, and the geometry of
the cells can all be selected to control the expansion, strength,
and sizing of the finished connector. The number and shape of the
radially outwardly deflectable connector members can also differ
from what is shown herein. Techniques and apparatus different from
what is shown and described herein can be used for attaching a
connector of this invention to a graft conduit and/or installing
the connector in a patient. Instead of the extreme end of graft 120
being inside conduit 300, the connector of this invention may be
configured to secure the end of the graft 120 against the outside
of the side wall of conduit 300 in an end-to-side anastomosis as
shown in FIG. 23. The nose cone 220 of apparatus 200 may not need
to cover the proximal fingers 22 or 422 of the connector. Instead,
the proximal fingers can extend to an outer circumference which is
larger than the outer circumference of nose cone 220. This allows
the proximal fingers to be used as a stop which prevents the
connector from going too far through the aperture in the side wall
of conduit 300. In other words, the radially outer ends of proximal
fingers 22 or 422 come into contact with the outer surface of the
side wall of conduit 300 and thereby stop the connector from going
any farther into that conduit.
[0070] Although considerable variation in the connectors of this
invention is thus possible and contemplated, in general such
connectors comprise a unitary structure disposed annularly about a
longitudinal axis (e.g., axis 12 in FIG. 2). The connector
structure generally has axially spaced first and second portions
(e.g., 20 and 40, 420 and 440, or 640a and 640b in the depicted
illustrative embodiments). The first portion generally has a
plurality of annularly spaced first members that are deflectable
radially out from a remainder or other generally axially medial
portion of the structure. For example, in the illustrative
embodiment shown in FIGS. 1-11 these first members include elements
22. In the illustrative embodiment shown in FIGS. 12-19 these first
members include elements 422. In the illustrative embodiment shown
in FIGS. 24 and 25 these first members include elements 642a. The
second portion may also have a plurality of annularly spaced second
members that are deflectable radially out from a remainder or other
generally axially medial portion of the structure. For example, in
the illustrative embodiment shown in FIGS. 1-11 these second
members include elements 44 and (later in use of the connector) the
portions of elements 60 and 62 that are above elements 54 in FIG.
1. In the illustrative embodiment shown in FIGS. 12-19 the second
members include U-shaped structures that are the portions of
elements 460, 462, and 464 above elements 454 in FIG. 12. In the
illustrative embodiment shown in FIGS. 24 and 25 these second
members include members 642b. Also, in general, the connector
structures of this invention are annularly enlargeable. For
example, in the illustrative embodiment shown in FIGS. 1-11 the
connector is annularly enlargeable by enlarging cells 50/52/54/56
and 60/62/64/66 in the annular direction as shown, e.g., in FIG. 4.
Similarly, in the illustrative embodiment shown in FIGS. 12-19 the
connector is annularly enlargeable by enlarging cells
460/462/464/466 in the annular direction as shown, e.g., in FIG.
13. And in the embodiment shown in FIGS. 24 and 25 the connector is
annularly enlargeable by enlarging cells 660/664/666 in the annular
direction.
[0071] It will be appreciated that, in general, the structure of
the connectors of this invention is such that radial enlargement of
the connector reduces the axial spacing between the above-mentioned
first and second members. This helps the connector draw together in
a fluid-tight way the two body fluid conduits that are to be
connected by the connector. In the embodiment shown in FIGS. 1-11,
for example, annular enlargement of cells 60/62/64/66 causes a
decrease in the axial spacing between members 22, on the one hand,
and members 42, on the other hand. Similarly, in the embodiment
shown in FIGS. 12-19 annular enlargement of cells 460/462/464/466
causes a decrease in the axial spacing between members 422, on the
one hand, and the portions of elements 460 and 462 above elements
454 in FIG. 12, on the other hand. And in the embodiment shown in
FIGS. 24 and 25 annular enlargement of the connector decreases the
axial spacing between members 642a, on the one hand, and members
642b, on the other hand. The above-described axial shortening of
the connector advantageously applies compressive forces (for
sealing) to the body fluid conduits being connected.
[0072] In general, most of the deformation of the connectors of
this invention is preferably plastic strain and therefore
permanent. The deformation thus referred to includes both the
above-described radially outward deflection of members like 22, 42,
422, 642, etc., and the above-described radial enlargement of the
connector.
[0073] The radially outwardly deflectable members or portions of
the connector may be barbs, hooks, spikes, loops, or suture
rings.
[0074] The connectors of this invention may be constructed so that
different portions of the connector annularly enlarge in response
to different amounts of applied annular enlargement force. For
example, in the embodiment shown in FIGS. 1-11, the portions of the
structure above elements 54 in FIG. 1 may be made so that they are
less resistant to inflation of a balloon 110 inside the connector
than portions of the structure below elements 54 in FIG. 1. In an
application of the type shown in FIGS. 1-11 this causes these less
resistant portions to annularly enlarge by deflecting radially out
inside conduit 300 before the remainder of the connector begins to
significantly annularly enlarge. This early response of the less
resistant portions inside conduit 300 may help to ensure that the
connector does not slip out of engagement with conduit 300 during
annular enlargement of the connector. This technique of making
different portions of the connector with different strengths can be
used to provide any sequence or phasing of annular enlargement of
various portions of the connector. Alternatively or additionally,
the connector can be shaped, molded, or phased in any desired way
by providing a balloon structure 110 which is shaped, molded, or
phased in that way. For example, balloon structure 110 may comprise
two or more separately inflatable balloons of the same or different
inflated circumferential size. Two such balloons may be axially
displaced from one another inside the connector so that axially
different portions of the connector can be annularly enlarged at
different times and/or by different amounts.
[0075] Radiologically (e.g., x-ray) viewable markers can be used
anywhere on the connectors and/or delivery apparatus (e.g., 200) of
this invention to facilitate radiologic observation of the proper
placement and deployment of a connector in a patient if the
connector-utilizing procedure is such that more direct visual
observation is not possible or sufficient. One way to enhance the
radiologic viewability of connectors in accordance with this
invention is to make them from clad tubing. Clad tubing has two (or
more) substantially concentric layers of metal, each with a desired
property. As shown in FIG. 20, for example, clad tubing 500 has a
tantalum layer 502 over a stainless steel layer 504. The tantalum
layer 502 provides radiodensity, thereby making a connector 10,
410, or 610 that is cut from tube 500 radiologically viewable. The
stainless steel layer 504 provides rigidity to the connector. The
medial section can be ground to reduce the thickness ratio to favor
the tantalum. This improves the ability for balloon expansion.
Although tube 500 (and the resulting connector 10, 410, or 610) may
thus be made of two or more layers of different materials, the tube
and the connector are still accurately described as unitary,
one-piece, or integral. As an alternative to using clad tubing, the
connector may be plated with a radiologic material to give it a
desired radiodensity. Another example of a material suitable for
radiologic layer 502 is platinum.
[0076] Small polyester or other polymer patches or bands may be
used on or in association with a connector of this invention to
help seal and coagulate blood. Such patches may be inserted over
individual fingers as shown, for example, at 522 in FIG. 21.
Alternatively, such a band or web may be provided around the medial
portion of connector 10, 410, or 610 as shown, for example, at 530
in FIG. 22. A band or web like 530 may also be used to constrain
the size of the connector or a graft (such as a vein graft)
relative to the connector. Vein grafts may dilate significantly
under arterial blood pressure. A band or web can be used to fix its
size relative to the connector. Alternatively or additionally a
band or web like 530 can be provided to help seal the completed
anastomosis For purposes of these various kinds, a band or web like
530 may preferably be elastic (e.g., of a rubber or rubber-like
material such as silicone or polyurethane). The band or web like
530 can be porous, if desired, and may be impregnated with drugs to
facilitate healing and/or sealing. Similarly, polymer patches like
522 in FIG. 21 can include and release coagulant and/or other
medication to help prevent bleeding and promote healing. Patches
like 522 in FIG. 21 can help prevent members like 22 from pulling
back through tissue that the member has penetrated.
[0077] An important attribute of the connectors of this invention
is the characteristic that the medial section is soft enough to
allow balloon expansion and strong enough to secure the two body
fluid conduits via such elements as 22 and 42, 422 and 460/462/464,
or 642. To achieve this with a single material and wall thickness,
which may be preferable from a manufacturing perspective, the
center section may be annealed selectively to soften it without
compromising the rigidity of the retention elements (e.g., 22, 42,
422, 642, etc.). This can be done, for example, by laser heat
treating the medial section only. The results of this process are
relatively low hardness in the medial section and relatively high
hardness in the end sections, all within an overall length of about
0.2 inches.
[0078] The connectors of this invention may also be made of a
super-elastic material such as nickel-titanium ("nitinol"), which
would allow a similar geometry as stainless steel to self-deploy or
actuate in-vivo.
[0079] It will be appreciated that the fact that the connectors of
this invention can be initially relatively small in circumference,
and that they can be remotely controlled to position them in the
patient and to then annularly expand them for final deployment,
facilitates use of these connectors and associated apparatus (e.g.,
apparatus 200) at remote and/or inaccessible locations in a
patient. For example, a connector of this invention may be
delivered into and installed in a patient (using apparatus such as
apparatus 200) through relatively small instrumentation such as
laparascopic apparatus, a cannula, or an intraluminal catheter.
Thus a connector and associated apparatus (e.g., apparatus 200) of
this invention can be used in any of the procedures mentioned
earlier in this specification, and in particular in procedures and
with other elements shown in any of above-mentioned references WO
98/16161, U.S. Pat. No. 5,976,178, U.S. Pat. No. 6,120,432, WO
98/55027, and U.S. Pat. No. 6,475,222. Alternatively, the connector
and/or apparatus (e.g., apparatus 200) of this invention can be
used in more traditional or conventional surgical procedures or in
other, known, less invasive or minimally invasive procedures. As
just some examples of possible uses of the connectors and apparatus
of this invention, they can be used to perform an anastomosis to a
beating or still heart without the use of sutures or direct
access.
[0080] Again, although the connectors of this invention can be made
in various sizes for various uses, a typical connector is initially
less than about 1 millimeter in diameter and in the range from
about 2 to about 4 millimeters in length. After annular
enlargement, a typical connector is more than about 2.5 millimeters
in diameter. The pre-yield geometry of these connectors is ideal
for delivery and positioning; the post-yield geometry is ideal for
vessel securement, seal, and patency. The geometry of the
connectors is ideal for annular enlargement. Radial outward
deflection of certain connector members such as 22, 42, 422, 642,
etc., is ideal for interfacing the expanding medial section of the
connector to each of the two body fluid conduits to be connected
(e.g., a graft vessel and an artery vessel).
[0081] As has been explained, certain connector cells may be
configured to open before other cells as desired to optimize
deployment positioning. Integral connector fingers such as 22, 42,
422, 642, etc., can be deflected radially out from the remainder of
a connector for the purpose of attachment to body fluid conduits
(e.g., a graft and an artery). These fingers are part of the
connector body and can be hooks, barbs, loops, or spikes. The
geometry of the fingers can also change, as desired, in response to
balloon expansion. A balloon catheter can be used to actuate the
connector and provide an anastomosis opening and attachment. The
nose cone portion 220 of apparatus 200 covers the connector and
graft interface, allowing dilation of the other body fluid conduit
wall and passage of the connector through that wall. The connector
provides the actual anastomotic opening and the connection
simultaneously. The device is actuated via a balloon and catheter
delivery system.
[0082] Among the advantages of the invention are that it eliminates
suturing and reduces the time required to produce an anastomosis.
In major circulatory system repair procedures such as cardiac
bypass procedures, this can reduce cardiopulmonary pump time, which
is of great benefit to the patient. The invention provides optimal
flow dynamics, e.g., from a graft to the coronary artery. The blood
entrance angle can be engineered into the connector geometry rather
than relying on suture skill or technique. The invention eliminates
possible suture injury to vessels. At the high stress site of an
anastomosis sutures are eliminated. The connector and a graft can
be delivered percutaneously, e.g., as in several of the references
that are mentioned above. Direct access required for suturing is
eliminated. An anastomotic connection can be made to a beating
heart.
* * * * *