Methods and apparatus for making anastomotic connections larger than the graft conduit

Methods and apparatus for making an anastomotic connection between an opening at an end of a graft conduit and an aperture in a side wall of a body tissue conduit using a hollow connector assembly are provided, wherein the cross-sectional area of the anastomotic connection is larger than that of the graft conduit. The tissue about the opening is introduced about and retained by first members of a distal portion of the connector assembly held by a loading tool. A delivery tool then collapses a proximal portion defined by second members of the connector assembly and delivers the second members into the lumen of the body tissue conduit via the aperture. Upon inserting the second members into the body tissue conduit, the delivery tool is disemployed and the second members expand such that they press against the interior wall of the body tissue conduit and such that the first members are held within the aperture against a medial wall of the body tissue conduit.

BACKGROUND OF THE INVENTION

This invention relates to medical grafting apparatus and methods for creating anastomoses and, more particularly, to apparatus and methods for creating an aortic anastomoses whose ostium diameter is larger than that of the graft conduit.

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 (see, for example, Peterson et al. U.S. patent application Ser. No. 10/147,208, filed May 14, 2002, which is hereby incorporated by reference herein in its entirety). 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 attached to the coronary artery downstream from the obstruction may be supplied with aortic blood via an anastomosis to the aorta. The anastomosis may be between the end of the graft and an aperture in the side wall of the aorta (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 aorta (a so-called side-to-side anastomosis).

The graft may be natural conduit, synthetic conduit, or a combination of natural and synthetic conduits. If natural conduit is used, it may be wholly or partly relocated from elsewhere in the patient (e.g., wholly relocated saphenous vein graft (“SVG”), radial artery, or partly relocated internal mammary artery (“IMA”)).

In the case of making a conventional anastomosis utilizing commercially available connectors at the proximal anastomosis between the graft and the aorta, certain difficulties may arise. First, the relative sizes of the aorta and the graft are different. Currently, the ostium diameter of the anastomosis utilizing commercially available connectors is limited by and usually smaller than the diameter of the graft. The resulting quality and amount of flow between the vein graft and the aorta, along with the provision of an effective hemodynamic seal between the two vessels, is often dependent upon the physician's skill in making an effective junction therebetween.

Second, a conventional end-to-side anastomosis utilizing commercially available connectors typically joins the graft conduit to the aorta at a substantially perpendicular angle with respect to the lumen of the aorta, thus forming a junction at the wall of the aorta. Further away from this junction, the vein graft tends to lie against the heart structure, or substantially parallel to the aorta. The transition of the vein graft from a substantially perpendicular juncture to the aorta to a substantially parallel position with respect to the aorta wall often requires non-traditional placement of the anastomosis different from that of typical hand-sewn anastomoses.

Third, it is desirable to provide an anastomosis with a diameter equal to or larger than the diameter of the smaller vessel being joined in order to allow as much area as possible for the natural healing response.

Accordingly, it is an object of the invention to provide apparatus and methods for making an anastomosis whose ostium diameter is larger than that of the graft.

It is also an object of the invention to provide apparatus and methods for making an anastomosis whose take-off is angled rather than tangential or perpendicular.

SUMMARY OF THE INVENTION

It is therefore an object of this invention to provide apparatus and methods for making an anastomosis whose ostium diameter is larger than that of the graft.

It is therefore also an object of the invention to provide apparatus and methods for making an anastomosis whose take-off is angled rather than tangential or perpendicular.

In accordance with the present invention, an apparatus including a connector assembly is provided to create a hollow anastomotic connection between tubular body fluid vessels in a patient. A particular application of the invention is to join a graft conduit to a patient's aorta in an end-to-side anastomosis whose ostium diameter is larger than that of the graft conduit. In a first embodiment of the present invention, the connector assembly has a first set of members or graft retention features at its distal end that engage a first vessel (e.g., the graft conduit), and a second set of members or inside aortic fingers at its proximal end that contact a second vessel (e.g., the aorta) and press it towards the first vessel. A graft attachment band or lid is pivotally attached at the distal end of the connector. The inside aortic fingers are constrained by an aortic delivery tool such that the connector assembly is held about the medial portion of a “S-shaped” graft loading tool.

Tissue at a prepared end of the graft conduit is slid onto the distal portion of the loading tool, pulled through the band, and draped over the graft retention features at the distal end of the connector assembly. The band is then pivotally lowered to snap-fit with the distal end of the connector assembly to fixedly engage the graft conduit thereto.

The aortic delivery tool unconstrains the inside aortic fingers such that the graft loading tool can be removed from the graft conduit and through the connector assembly. Then the delivery tool re-constrains the inside aortic fingers such that they are positioned to prevent trauma to the aorta when the proximal end of the connector assembly is introduced therein. The delivery tool has a structure which may release the inside aortic fingers therefrom after insertion into the aorta and to allow expansion of the proximal end of the connector assembly therein.

A method for creating the anastomosis may include introducing the prepared end of the graft conduit through the band of the connector assembly and then over its distal end to engage the graft conduit with the graft retention features of the connector assembly. At the operative site, an aperture may be made in the side wall of the aorta or any other body conduit that, is to be connected to the graft. The proximal end of the connector assembly may be deformed and the end of the graft conduit and the aperture in the aorta may be approximated so that the inside aortic fingers of the connector assembly extend into the aorta via the aperture. The connector assembly may reform so that it presses together the exterior wall of the aorta and the end of the graft conduit annularly about the aperture in the aorta.

It should be noted that the terms vessel and conduit are used interchangeable herein.

DETAILED DESCRIPTION OF THE INVENTION

Although the invention has other possible uses, the invention will be fully understood from the following explanation of its use in providing a bypass around an obstruction in a patient's vascular system.

In some embodiments of the present invention, certain types of cuts may be made at the end of a graft conduit prior to creating an end-to-side anastomosis between the graft conduit and the aorta of a patient such that the ostium diameter of the anastomosis may be larger than that of the graft conduit. (It should be noted that, although apparatus and methods for making anastomoses generally may be described herein in relation to those whose ostium diameter is larger than that of the graft, the present invention also relates to making anastomoses whose ostium cross-sectional area, and not necessarily diameter, is larger than that of the graft, for example, when the ostium is oval-shaped.)

FIGS. 1 and 2show a length of a graft10, having an inner diameter12, prepared with a “cobra head” or “spatulated” cut. Firstly, an incision14oblique to the longitudinal axis of graft10at an angle θ is made at an open end11of graft10from a point16, referred to herein as the “toe.” Secondly, a lengthwise axial incision18, which may be substantially the same length as incision14, is made from the end of incision14to a point20along the length of the graft, referred to herein as the “heel.” The cross-sectional area of opening22from toe16to heel20provided by the spatulated cut of graft10increases as the length of incision18increases and/or the length of incision16increases (i.e., as angle θ decreases), thereby allowing the ostium cross-sectional area of an anastomosis made with spatulated graft10to be larger than that of an anastomosis simply made with open end11of the native graft.

FIGS. 3 and 4show an other embodiment of the present invention, wherein the length of a graft30having an inner diameter32is prepared with an “axial” cut. A lengthwise axial incision38is made at open end31of graft30from a point diametrically opposite toe point36to a heel point40along the length of graft30. The cross-sectional area of opening42from toe36to heel40provided by the axial cut of graft30increases as the length of incision38increases, thereby allowing the ostium cross-sectional area of an anastomosis made with axially cut graft30to be larger than that of an anastomosis simply made with open end31of the native graft.

FIGS. 5 and 6show yet an other embodiment of the present invention, wherein the length of a graft50having an inner diameter52is prepared with an “oblique” cut. An incision54oblique to the longitudinal axis of graft50at an angle θ′ is made at an open end51of graft50from a toe point56to a heel point60along the length of graft50. The cross-sectional area of opening62from toe56to heel60provided by the oblique cut of graft50increases as the length of incision54increases (i.e., as angle θ′ decreases), thereby allowing the ostium cross-sectional area of an anastomosis made with obliquely cut graft50to be larger than that of an anastomosis simply made with open end51of the native graft.

It should be noted that, in order to provide an opening with a cross-sectional area that is larger than that provided by a conventional transverse cut, the end of a graft conduit to be used in an aortic anastomosis may be prepared with various cuts other than those described above. As described hereinabove with respect toFIGS. 1-6, the length and type of each incision used while preparing a cut at an open end of a graft conduit may be adjusted based on the inner diameter of the graft conduit, the outer diameter of the connector, and amount of residual toe tissue of the graft conduit, for example, such that the cross-sectional area of the opening created may be customized to match the size and shape of the ostium of the connector used in making the aortic anastomosis.

FIGS. 7 and 7Ashow an illustrative connector assembly500to be used for making an aortic anastomosis using an end of a graft conduit prepared in any of the ways described above such that the ostium cross-sectional area is larger than that of the graft conduit. As shown, for example, there may generally be four components to connector assembly500: a connector “body”100with inside aortic fingers, an “inside-the-graft” retaining element or ring200that may be fixed or part of connector body100, an “outside-the-graft” retaining element or band300pivotally attached or attachable to connector body100at a point below “inside-the-graft” ring200, and a locking or sliding collar400fitted about a portion of outside-the-graft band300for fastening outside-the-graft band300below inside-the-graft ring200.

In a preferred embodiment, band300is allowed to pivot on connector body100at a point below ring200to facilitate loading of the graft. Outside-the-graft retaining band300has several features which allow it to function as a retaining feature. For example, the effective inner diameter of outside-the-graft retaining band300may be equal to or less than the effective outer diameter of inside-the-graft retaining ring200. This interference fit between the two elements may facilitate a locking mechanism. Tissue retention features on the outside of inside-the-graft retaining ring200and tissue retention features on the inside of outside-the-graft retaining band300may allow deflection so that the band and ring can pass by each other to latch, but the shape and resulting direction of force may make release of this mechanism, or the ability for the band and ring to pass back the other way, to require significant force. The geometry of these features can take many forms other than those described herein without departing from the spirit and scope of the present invention. In another preferred embodiment, band300is attached about connector body100at least partially below ring200after the graft has been loaded about ring200.

Components100,200,300and400may be constructed of nitinol, stainless steel, or any other suitable material, or combination thereof. The inside-the-graft retaining ring may or may not be attached to the connector body. The entire structure could be cut from one piece of nitinol tube and formed into the desired features, for example. Provided hereinbelow are brief descriptions of drawings in connection with the separate components of connector assembly500.

FIG. 8shows a planar development of what is actually, preferably, an integral, one-piece (unitary), annular, cellular connector body100. In particular, the left and right edges of the structure shown inFIG. 8are actually, preferably, joined to and integral with one another. Thus, the actual structure of connector body100is as shown inFIGS. 7,7A,9, and10, althoughFIG. 8is useful to more clearly reveal certain details of various features of connector body100. A central longitudinal axis110about which connector body100is annular is shown inFIGS. 9 and 10.

A particularly preferred material for connector body100is nitinol. Other examples of suitable materials include tantalum, tungsten, stainless steel, platinum, silicone, and polyurethane. Connector body100may be advantageously produced by starting with a single, unitary tube, such as a hypotube, and removing selected material until only the structure shown inFIGS. 9 and 10remains. For example, laser cutting may be used to remove material from the starting tube in order to produce connector body100. After removing the material to form the structure shown inFIG. 8, the machined tube may be placed in a mold and heat-shaped into approximately the geometry that connector body100will assume after deployment. For example, connector body100may be heat-shaped into the geometry shown inFIGS. 9 and 10. The shape of connector body100is retained after removing connector body100from the mold due to the properties of nitinol.

Connector body100may be described as including annularly spaced cell portions112. Cell portions112may also be referred to herein as “inside aortic fingers.” According to one embodiment, connector body100includes eight repeating cell portions112. Connector body100may have fewer or more than eight of cell portions112, depending on the axial length and perimeter of the tube used to manufacture connector body100and the desired ostium size of the resulting anastomosis. Alternatively, the structure of connector body100may have different configurations of cells and geometries.

Each cell112includes a pair of annularly spaced members120. Each cell112typically also includes a pair of annularly spaced members122. The proximal end of each member122is connected to the distal ends of adjacent members120of adjacent cells112, and the distal ends of members122are connected to the proximal portion of an annular element124. Annular element124defines the distal portion114of connector body100, whereas annularly spaced members122define the medial portion116of connector body100. Members122of annularly adjacent cell portions112may typically be separated by a distance113with a length in a range from about 0.065 inches to about 0.100 inches. (It should be noted that distance113includes the width of members120.) A typical annularly spaced member122may have a length115in a range from about 0.060 inches to about 0.080 inches. However, the dimensions of annularly spaced members122may be altered according to the diameter or cross-sectional area of the graft conduit to be used in the anastomosis, for example.

The proximal ends of annularly spaced members120of each cell112are typically connected to one another at an annularly extending member126, which is preferably curved proximally. A pair of members120and a member126define the proximal portion118of each cell portion112. In each cell112, the most proximal point of member126and the most distal point of annular element124distal thereto may typically be separated by a distance117with a length in a range from about 0.225 inches to about 0.250 inches. (It should be noted that the length of distance117includes the width of member126and the width of annular element124.)

As shown in this example, connector body100preferably has a fixed cross-sectional area. Specifically, annular element124of distal portion114is an annular structure having a fixed cross-section, an outer surface123, an inner surface121, and an opening125defined therein, which may be round, oval, or any other substantially smooth shape. In another preferred embodiment, connector body100may be annularly expandable or enlargeable, whereby opening125may be fixedly held by ring200in connector assembly500, as will be described in more detail below.

As shown inFIGS. 9 and 10, inside aortic fingers112may expand radially out from distal portion114. As described above, fingers112may expand to the configuration created by heat-shaping connector body100. The expansion of fingers112is preferably elastic. One adjacent member120of each finger112may be provided with an aortic eyelet128for interaction with an aortic delivery tool such that proximal portion118may be configured to pass through an aperture in the aorta, as described in more detail below (see, e.g.,FIGS. 31-33). (It should be noted that fingers112are not shown in their expanded configuration inFIGS. 7 and 7Afor clarity sake.)

A plurality of receiving slots130may be provided along annular element124for receiving inside-the-graft retaining ring200, as described in more detail below. Moreover, at a first annularly spaced member122there is provided a hinge joint132for interaction with outside-the-graft retaining band300, as described in more detail below. Connector body100also typically requires other processing appropriate for an implantable device such as, for example, polishing, passivation, cleaning, and sterilizing.

FIG. 11shows in isolation substantially annular inside-the-graft retaining element or ring200, which may be fixed or part of connector body100in connector assembly500ofFIGS. 7 and 7A, althoughFIG. 11is useful to more clearly reveal certain details of various features of ring200. Like connector body100, a particularly preferred material for ring200is nitinol. Other examples of suitable materials include tantalum, tungsten, stainless steel, platinum, silicone, and polyurethane. Ring200may be advantageously produced along with connector body100and connected or fixed thereto, such that the two components may be assembled and provided by the manufacturer to the physician as a single-piece device.

Inside-the-graft retaining ring200may generally be described as including an annular element202with an inner surface201sized such that it may substantially match the shape of annular element124of connector body100in assembly500ofFIGS. 7 and 7A. Tabs204are provided around inner surface201of element202and project inwardly in substantially the same plane as ring200. Tabs204are appropriately spaced around inner surface201such that each tab204may pass through a respective slot130in annular element124of connector body100when ring200is positioned thereabout, as shown inFIGS. 7 and 7A. Slots130in annular element124and tabs204of annular element202interact to join the outer surface123of connector body100and the inner surface201of ring200in connector assembly500.

Ring200may also be described as including at least one flange projecting outwardly from element202in substantially the same plane as tabs204. According to one embodiment, ring200includes two spaced flanges206projecting from the portion of element202spaced substantially diametrically opposite the portion of element202which interacts with annular element124just distal of hinge132of connector body100, as shown inFIGS. 7 and 7A. Ring200may have fewer or more than two flanges206, depending on the size and shape of annular element124of connector body100, for example. Alternatively, the structure of connector body100may have different configurations of cells and geometries. Furthermore, ring200may also include one or more inside-the-graft retention features or teeth208projecting outwardly from outer surface203of ring200about element202and flanges206.

FIG. 12shows in isolation substantially annular outside-the-graft retaining element or band300, which may be hingedly or pivotally coupled to connector body100in connector assembly500ofFIGS. 7 and 7A, althoughFIG. 12is useful to more clearly reveal certain details of various features of band300. Like connector body100and ring200, a particularly preferred material for band300is nitinol. Other examples of suitable materials include tantalum, tungsten, stainless steel, platinum, silicone, and polyurethane. Band300may be advantageously produced along with connector body100and ring200and connected thereto, such that the components may be assembled and provided by the manufacturer to the physician as a single-piece device.

Outside-the-graft retaining band300may generally be described as including a substantially annular element302with an inner surface301whose size and shape may match that of outer surface203of annular element202of inside-the-graft retaining ring200. Hinge eyelets304are provided at a portion of outer surface303of element302. Hinge eyelets304are appropriately spaced around outer surface303such that they interact with hinge joint132of connector body100when they are heat treated or bent out of the plane of element302towards each other and when band300is coupled to connector body100, as shown inFIGS. 7 and 7A. Hinge joint132of connector body100and hinge eyelets304of band300interact such that band300may turn or pivot on connector body100to pass from a first “open” position, as shown inFIGS. 7 and 7A, beyond ring200, to a second “closed” position thereunder, as described in more detail below (see, e.g.,FIGS. 14-18). Band300may also include one or more outside-the-graft retention features or teeth308projecting inwardly from inner surface301of band300about element302. It is to be understood that inside-the-graft retention features208and outside-the-graft retention features308may be of variable frequency about annular elements202and302, respectively, and may be of variable lengths and shapes, such as “fanged” or “barbed,” for example.

Band300may also be described as including one or more outside aortic fingers306projecting outwardly from element302in substantially the same plane as element302and may be bent or heat treated to curve out of the plane to engage the exterior wall of the aorta when the anastomosis is completed, as described in more detail below (see, e.g.,FIG. 35). According to one embodiment, band300includes two diametrically spaced outside aortic fingers306projecting from element302at points equally removed from hinge eyelets304. Band300may have fewer or more than two aortic fingers306, depending on the size and shape of annular element124of connector body100, for example.

Expansion portion310is included as an integral element of band300. Expansion portion310may include first and second band eyelets312and314that interrupt substantially annular element302at ends307and309, respectively. In a preferred embodiment, ends307and309may generally be provided by element302at a location equally separated from outside aortic fingers306and substantially diametrically opposite hinge eyelets304, for example.

Expansion portion310may also include parallel first and second arms316and318projecting outwardly from element302at band eyelets312and314, respectively, and joining together at a resilient joint320. One or more sets of notches322may be provided along the length of arms316and318such that collar400may be retained thereabove or therebelow when collar400is positioned about expansion portion310in connector assembly500, as shown inFIGS. 7 and 7A, and as described in more detail below. Furthermore, expansion portion310may also include a cap element, such as tip element324, coupled to resilient joint320for retaining collar400about expansion portion310. In a preferred embodiment, tip element324and first and second arms316and318may be bent or heat treated to curve out of the plane of annular element302for engaging the exterior wall of the aorta when the anastomosis is completed, as described in more detail below (see, e.g.,FIG. 34).

FIG. 13shows in isolation locking or sliding collar400, which may be positioned about arms316and318of expansion portion310of band300in connector assembly500ofFIGS. 7 and 7A, althoughFIG. 13is useful to more clearly reveal certain details of various features of collar400. Like connector body100, ring200, and band300, a particularly preferred material for collar400is nitinol. Other examples of suitable materials include tantalum, tungsten, stainless steel, platinum, silicone, and polyurethane. Collar400may be advantageously produced along with band300, ring200, and connector body100, and attached thereto, such that the components may be assembled and provided by the manufacturer to the physician as a single-piece device.

A preferred embodiment of locking, snapping, or sliding collar400may generally be described as including a band slot406sized such that arms316and318of band300may pass therethrough in assembly500ofFIGS. 7 and 7A. First and second collar eyelets402and404may also be provided through collar400, generally flanking slot406. Collar eyelets402and404are appropriately spaced such that they may align with band eyelets312and314, respectively, when arms316and318are passed through slot406of collar400, as described below in more detail (see, e.g.,FIGS. 16 and 17).

As described above, band300may be hingedly coupled to hinge joint132at medial portion116of connector body100such that element302may pivot on connector body100to pass from a first “open” position, beyond annular element202of ring200coupled to distal portion114of connector body100, to a second “closed” position proximal thereto. Moreover, in a preferred embodiment, inner surface301of element302is of substantially the same size and shape as outer surface203of element202. Therefore, expansion portion310and collar400must manipulate element302such that inner surface301of element302may pass from an open position (see, e.g.,FIGS. 7 and 7A), beyond outer surface203and flanges206of element202, to a closed position therebelow.

As shown inFIG. 14, when in its open position, ends307and309of substantially annular element302may first be further separated from one another (e.g., by a physician's tool) about resilient joint320in the directions of arrows350and351, respectively, thereby increasing the size and shape of the opening defined by inner surface301. Collar400is preferably retained about expansion member310between tip element324and notches322, but above joint320, such that collar400does not limit the distance by which ends307and309may be separated about joint320. Once the opening defined by inner surface301is increased to a suitable size and shape, element302may be passed in the direction of arrows352beyond outer surface203and flanges206of element202.

As shown inFIGS. 15 and 16, once element302is passed proximally beyond outer surface203and flanges206of element202, ends307and309may be allowed to move back towards one another about joint320, such that inner surface301contracts to its original size and shape about connector body100proximal to ring200.

Finally, in a preferred embodiment, ends371and373of a suture line375passed through aligned eyelets312and402and also through aligned eyelets314and404, as shown inFIGS. 16 and 17, may be pulled in the direction of arrow376such that collar400is also pulled in the direction of arrow376proximally over notches322. Preferably, once collar400is moved proximally over notches322and snapped into place, expansion portion310is not only configured to retain collar400between notches322and flanges206of ring200, but is also configured to retain flanges206between collar400and annular element302, as shown inFIG. 17, thereby holding band300in its closed position along with hinge132/304(also see, e.g.,FIG. 18, wherein outside aortic fingers306are not shown for sake of clarity). Suture line375may then either be left alone or removed from connector assembly500.

In another embodiment, collar400may simply be pushed proximally over notches322, thereby obviating not only suture line375but also eyelets312,314,402, and404. In yet another embodiment described in more detail below with respect toFIGS. 44-46, an outside-the-graft retaining band may be substantially annular and provided with one or more expansion portions such that its inner surface may expand stretch to be larger than outer surface203and flanges206of element202. In this embodiment, the outside-the-graft retaining band may be coupled to body connector100at the time of its expansion, rather than being hinged thereto, thereby obviating not only collar400, but also hinge eyelets304. In yet still another embodiment, element302of band300may be completely annular but resilient such that its inner surface may elastically stretch to be larger than outer surface203and flanges206of element202. In this embodiment, element302may simply be stretched to pass beyond element202and then released to contract below ring200about annular element124of body connector100, thereby obviating not only hinge eyelets304, but also collar400and expansion portion310.

A typical use of connector assembly500is to provide an anastomosis between an end of a graft conduit and an aperture in a side wall of the aorta in a coronary bypass procedure, as described above. An illustrative apparatus for deploying connector assembly500such that it engages a tubular graft conduit and a patient's body tissue conduit (e.g., aorta) is shown inFIGS. 19-24.FIGS. 19 and 20are an isometric view of apparatus600and connector assembly500(FIGS. 7-19) andFIGS. 21-24show certain components of apparatus600in isolation to further illustrate their features.

Apparatus600may include aortic delivery tool700(portions of which are shown in isolation inFIGS. 21-23) and graft loading tool800(shown in isolation inFIGS. 24 and 24A) coupled thereto. Graft loading tool800is preferably a one-piece element, and may include a loading arm portion810, a loading body portion820, and a loading lead portion830. Loading arm portion810may extend substantially parallel to a portion of aortic delivery tool700and may be releasably attached thereto by a coupling member815provided at a proximal end811of arm portion810. Body portion820may extend from a distal end812of arm portion810and may pass through connector body100substantially along its central longitudinal axis110(FIGS. 9 and 10) such that a bulbous head825is generally positioned distally of annular element124. The bulbous shape of head825is desirable to aid in defining the resulting shape of the anastomosis external to the aorta, as will be described in more detail below (see, e.g.,FIG. 28). Tool800may also be described as including one or more resilient tissue holding elements823extending from distal end812of arm portion810about body portion820towards head825. Elements823may be bent or heat treated to resiliently contact the exterior of body portion820generally below head825to releasably hold the exterior wall of the graft conduit against body portion820as it is loaded on connector assembly500, as described in more detail below and shown inFIG. 27A, for example. It is to be noted that elements823are not illustrated inFIGS. 19 and 20for the sake of clarity. According to one embodiment, tool800includes two diametrically spaced tissue holding elements823. Tool800may have fewer or more than two tissue holding element823, depending on the size and shape of annular element124of connector body100, for example. A lead portion830may preferably extend from head825of body portion820through band300. Lead portion830may include a tip835at its distal end that is preferably tapered to enable the end of a graft conduit to slide onto lead portion830without damage, with minimal force being required, and with no catching or snagging on the walls of the conduit, as will be described in more detail below (see, e.g.,FIGS. 27 and 28).

Aortic delivery tool700may generally be described as including a physician control portion710, a delivery arm portion720, and a delivery lead portion730. Delivery arm portion720may extend distally from physician control portion710and substantially parallel to loading arm portion810of graft loading tool800. An opening725at distal end722of arm portion720exposes the distal ends of lumens727and729, which may extend proximally through arm portion720to physician control portion710. Lead portion730may extend away from distal end722of arm portion720. Lead portion730may include a tip735at its distal end that is preferably tapered to enable its insertion into the lumen of an aorta through an aperture or incision therein with minimal damage, with minimal force being required, and with no catching or snagging on the walls of the aorta, as will be described in more detail below (see, e.g.,FIGS. 33 and 34). Furthermore, a bar723may be provided proximal to end722of arm portion720and substantially transverse thereto, such that during insertion of tip735into the lumen of an aorta, bar723may contact the exterior of the aorta to limit the length of lead portion730passed therein, as will be described in more detail below (see, e.g.,FIG. 33).

FIG. 20shows the inside aortic fingers or cells112of connector body100(FIGS. 8-10) constrained around loading body portion820of graft loading tool800by an illustrative constraining device of the present invention. This may be accomplished using a constraining member, which may be fine wire less than 0.020 inches in diameter and made of nitinol, steel, nylon, polypropylene, silk, etc., in order to constrain the inside aortic fingers into a configuration that allows the connector assembly to be loaded with graft and aortic tissue. This constraint may be a noose, slip knot, quick release tie, or of various other configurations. The connector assembly itself may or may not have features that guide the path of the constraining member. The constraining member may be part of the delivery device or the connector assembly itself. The method for such constraint and release is benefitted by the reduction in friction between the constraining member and the connector assembly. Material choice and connector assembly geometry can greatly influence the functionality of the constraining member. Connector assembly geometry that allows the constraining member to have a continuous path minimizes the point contacts that cause the member to deflect from its desired path. Constraining members which pass through, or are contained or constrained by the connector assembly can be accomplished in several ways including, but not limited to, having connector assembly geometry that easily deforms in a way that facilitates a continuous radius path, having geometry that allows the constraining member to take a path with minimum deflections from the continuous radius, or having multiple constraining members which reduce the need for a multiple deflection and contact points. For constraining members which do not pass through or are not contained in the connector assembly geometry, the functional geometry components may consist of geometry which guides or positions the constraining member in the desired location to facilitate proper constraint and release of the connector assembly.

In the preferred embodiment shown inFIGS. 19-33, connector assembly500is constrained by a noose configuration of delivery tool700, whose wire728follows a path around body portion820of graft loading tool800and through the aortic eyelet128of each aortic finger112. The noose may be pulled tightly to constrain connector assembly500about body portion820of graft loading tool800such that inside aortic fingers112are not in their expanded configuration (FIGS. 9 and 10) but rather such that inside aortic fingers112are held in a constrained position proximally removed from element124and ring200. This further exposes the distal portion of the connector assembly geometry that is to constrain and hold the tissue of the graft conduit.

FIGS. 21-23show the components of aortic delivery tool800that provide the noose. An exposed loop portion726of wire728is provided at the distal ends of lumens727and729through opening725at distal end722of arm portion720. Loop portion726may follow a path around body portion820of graft loading tool800and through the aortic eyelet128of each aortic finger112, as described above and shown inFIGS. 19 and 20. The remaining portion of wire728may pass through lumens727and729, along delivery arm portion720, and into housing715of physician control portion710. Ends728aand728bof wire728each may be coupled to a respective one of spools717and719fixed to a rod716passing through housing715. Rotatable disc718may be fixed to rod716such that a physician may impart rotation to spools717and719via disc718and rod716. By rotating disc718, and thereby spools717and719, in the direction of arrow711, wire728is wound onto both spools. Conversely, by rotating disc718in the direction of arrow712, wire728is unwound from spools717and719. Therefore, by winding wire728onto spools717and719through rotation of disc718in the direction of arrow711, loop portion726may be pulled tightly to constrain connector assembly500about body portion820of graft loading tool800, and by unwinding wire728from spools717and719through rotation of disc718in the direction of arrow712, loop portion726may be loosened such that inside aortic fingers112are able to expand radially out towards their expanded configuration. In another embodiment, ends728aand728bof wire728may each be coupled to a single spool fixed to rod716, for example.

Apparatus600may be used to load a tubular graft conduit onto connector assembly500for creating an aortic anastomosis. Prior to loading the graft onto connector assembly500, an end of the graft may be prepared with a type of cut to provide an opening such that the ostium cross-sectional area of the anastomosis may be larger than that of the end of the native graft conduit. Preferably, such an opening has a cross-sectional area that is at least equal to that of opening125of annular element124of connector assembly500(see, e.g.,FIG. 10).

A graft conduit900is subsequently loaded onto connector assembly500about an opening902prepared at an end911of graft conduit900. As shown inFIG. 26, for example, interior surface901of graft conduit900defines a lumen908having an inner diameter912for providing fluid flow therethrough substantially along central longitudinal axis910of graft conduit900. Lumen908may generally be described as having a cross-sectional area transverse to axis910(and parallel to inner diameter912) that is smaller than that of opening902. Graft conduit900may 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, which is hereby incorporated by reference herein in its entirety), or a combination of natural and artificial conduits (e.g., a length of natural conduit disposed substantially concentrically inside a length of artificial conduit).

Opening902with a cross-sectional area larger than that of lumen908transverse to axis910may be prepared at end911of graft conduit900with any of the types of cuts and methods described above with respect toFIGS. 1-6or combinations thereof. In one example, opening902is made by preparing an axial cut at end911of graft conduit900with a blade. For example, a lengthwise axial incision may be made from a point918opposite toe point916at end911to a heel point920, whereby the segments of tissue between points916,918, and920define periphery905of opening902. The length of the axial incision may preferably be about 2-4 times that of the diameter or major axis (if oval) of annular element124, about which graft conduit900is to be loaded. However, the size of the initial incision may be adjusted based on the inner diameter of graft conduit900, the outer diameter of the connector, and amount of residual toe tissue of graft conduit900, for example, such that the cross-sectional area of opening902created may be customized to match the size and shape of the ostium of the connector used in making the aortic anastomosis. Other examples of cutting methods and apparatus for preparing an opening at an end of a graft conduit are described, for example, in published Patent Cooperation Treaty (“PCT”) patent application publication No. WO 01/39672, published Jun. 7, 2001, which is hereby incorporated by reference herein in its entirety.

For attachment, graft conduit900may be positioned adjacent to tip835of graft loading tool800such that opening902at end911faces connector assembly500and such that central longitudinal axis910is axially aligned with the length of lead portion830. As illustrated inFIG. 27, toe916and heel920of opening902may be advanced in the direction of arrows921and922, respectively, about lead portion830of loading tool800, through substantially annular element302of outside-the-graft retaining band300, and about inside-the-graft retention features208of inside-the-graft retaining ring200, such that all points substantially about periphery905of opening902are draped over annular element124of connector body100and about inside-the-graft retention features208. Then, tissue holding elements823may preferably be manipulated to press against exterior surface903of periphery905, thereby holding conduit900about body portion820of tool800and about inside-the-graft retention features208of connector assembly500, as shown inFIG. 27A, for example.

FIG. 28shows toe916and heel920advanced such that interior surface901substantially adjacent periphery905of opening902envelops inside-the-graft retention features208of ring200. Periphery905has passed proximally beyond ring200whereby the interior surface901substantially directly adjacent heel920may be positioned to engage the inside-the-graft retention features208adjacent hinge joint132of connector body100. Preferably, the clearance between the periphery defined by retention features208and periphery905adjacent to heel920is minimal such that the remainder of periphery905may be substantially centered about axis110of connector assembly500and draped thereabout to ensure that each retention feature208of ring200engages some portion of interior surface901of graft conduit900, as shown inFIG. 29, for example. The take-off angle of the aortic anastomosis created by graft conduit900may be variably increased by the physician, for example, by increasing the amount of tissue at periphery905adjacent to toe916passed beyond the retention features208of ring200, generally designated as amount913. Furthermore, it is to be understood that the take-off angle may also preferably be varied by the relative sizes of the inside diameter of the graft conduit (e.g., inside diameter912) and the outside diameter of the inside-the-graft retaining ring (e.g., the outside diameter of annular element203). It is also preferable that periphery905is draped such that interior surface901contacts head825to help define the resulting shape of the anastomosis, as shown inFIG. 28, for example.

With continued reference toFIG. 28, periphery905of opening902of graft conduit900is substantially fixed to connector assembly500about annular element124of connector body100. More particularly, band300has pivoted on hinge joint132of connector body100in the direction of arrow325(FIG. 27) such that element302has passed from an open position about lead portion830(see, e.g.,FIG. 27), proximally beyond ring200, to a closed position thereunder, as described above with respect toFIGS. 14-18. As shown inFIG. 28, once band300has been locked in its closed position by collar400, interior surface901substantially adjacent periphery905of opening902envelops inside-the-graft retention features208of ring200and exterior surface903substantially adjacent periphery905of opening902is engaged by outside-the-graft retention features308of band300. The substantially opposite forces applied to surfaces901and903of graft conduit900by inside-the-graft retention features208and outside-the-graft retention features308, respectively, may hold graft conduit900in a substantially fixed position about annular element124of connector assembly500. It will be appreciated that the perimeter of the ostium created by connector assembly500through opening911in graft conduit900is not defined by periphery905, but instead is limited by inner surface121of annular element124, which may have a cross-sectional area larger than that of graft conduit900.

Inside-the-graft retention features208of ring200may penetrate and pass through the side wall of graft conduit900from interior surface901to exterior surface903as a result of, for example, compressing the graft against the tips of features208with a physician's tool (e.g., the vein piercing tool described in Logan et al. U.S. Pat. No. 6,669,256, which is hereby incorporated by reference herein in its entirety), thereby forcing the free end portions of features208to pierce through the graft wall. Sharpened tips of the free end portions of features208may facilitate penetration of conduit900, while blunt rear surfaces may resist withdrawal therefrom, like a barb. Conduit900may be additionally or alternatively directly sutured to connector body100. Alternatively, conduit900may be secured to connector body100by, for example, pinching, inverting, clinching, stretching, or any other suitable manner of attaching the graft to the connector, with or without glues, clips, or any other connector elements.

Once collar400has locked band300in its closed position such that graft conduit900is held about annular element124of connector assembly500, loop portion726may be loosened by unwinding wire728from spools717and719through rotation of disc718, as described above (see, e.g.,FIGS. 21-23), such that inside aortic fingers112may expand radially out towards their expanded configuration (see, e.g.,FIGS. 9 and 10). Tissue holding elements823may be manipulated to disengage from exterior surface903of conduit900, coupling member815may be detached from delivery arm portion720, and graft loading tool800may be removed from within graft conduit900and connector assembly500, as shown inFIG. 30. The ostium may then be examined by the physician.

Next, loop portion726may be tightened again by winding wire728onto spools717and719through rotation of disc718as described above (see, e.g.,FIGS. 21-23) to re-constrain inside aortic fingers112such that each annularly extending member126of connector body100substantially converges with the other annularly extending members126at a convergence750. The geometry and deformability of inside aortic fingers112, the length of members120and122, position of aortic eyelets128therealong, and the manner in which wire728of loop portion726is threaded through the aortic eyelet128of each aortic finger112may determine whether the annularly extending member126of a particular finger112is held tightly on top of, underneath, or, as in the preferred embodiment shown, against the annularly extending member126of an adjacent finger112at convergence750(see, e.g.,FIGS. 31 and 32). When inside aortic fingers112are re-constrained by aortic delivery tool700, convergence750is preferably held against lead portion730. It is to be understood that in the embodiment where inside aortic fingers112are re-constrained such that they overlap each other, the size and shape of proximal portion118of connector body100may be substantially reduced.

As shown inFIG. 33, tip735may be inserted into aperture1002of a patient's tubular body tissue conduit1000(e.g., a patient's aorta requiring a bypass graft) to connect graft900to the body tissue conduit. Aperture1002may be formed, for example, by using a cutting catheter to cut through body tissue conduit1000at the desired anastomosis site (e.g., as in published PCT patent publication No. WO 99/38441, published Aug. 5, 1999, which is hereby incorporated by reference herein in its entirety). The natural elastic recoil of side wall1011of body tissue conduit1000seals aperture1002around lead portion730and connector assembly500so that there is little or no body fluid (e.g., blood) leakage out of the body conduit via aperture1002. Tip735is gradually forced through aperture1002in the direction shown by arrow755, thereby delivering convergence750and lead portion730into lumen1008of body conduit1000until external surface303of band300about periphery905of opening902of graft conduit900presses against the perimeter of aperture1002on medial portion1005of side wall1011of body tissue conduit1000. The size and shape of external surface303of connector assembly500is preferably nominally larger than that of the aortotomy, thereby resulting in sufficient contact pressure for forming a seal between aperture1002and band300(and, thus, graft conduit900). Bar723may be positioned along arm720such that it contacts exterior surface1003of body conduit1000to prevent delivery tool700from being inserted too far into lumen1008.

Once this occurs, inside aortic fingers112may be completely released by loop portion726such that they may fully expand radially out towards their expanded configuration (see, e.g.,FIGS. 9 and 10) and such that delivery tool700may be removed from the anastomosis site. In a preferred embodiment, fingers112may be completely released by winding wire728even more tightly onto spools717and719through rotation of disc718such that a frangible section about loop portion726of wire728may break within lumen1008of body tissue conduit1000due to the winding force at ends728aand728b(FIGS. 22 and 23). As shown inFIG. 33(andFIG. 32in hashed lines), once loop portion726breaks, wire728defines two separate wire segments spanning from ends728cand728dwithin lumen1008to ends728aand728bwithin housing portion715(FIG. 22), respectively. In another embodiment, the frangible section of wire728may not be about loop portion726but rather along a portion of wire728within lumen727, lumen729, or housing715. In yet another embodiment, the physician may manually clip a portion of wire728such that it is separated into two wire segments. In yet still another embodiment, one of ends728aor728bmay be released from its respective spool717or719such that wire728may just be wound onto the other one of the spools, for example.

With continued rotation of disc718in the direction of arrow711(FIGS. 22 and 23), the two wire segments are threaded out from eyelets128of fingers112, through opening725and lumens727and729, and possibly wound onto their respective spools717and719, if desired. As wire728is threaded out from eyelets128, fingers128are released from the confines of loop portion726and may freely expand radially out towards their expanded configuration shown inFIGS. 34 and 35. Once inside aortic fingers112are released from wire728, delivery tool700is preferably withdrawn from lumen1008and the elasticity of conduit1000about aperture1002preferably closes about connector assembly500. In their expanded configuration, fingers112may press against interior surface1001of body conduit1000about aperture1002with a force opposite that applied by outside aortic fingers306(and, preferably, by tip element324) against exterior surface1003of body conduit1000about aperture1002for sealing the anastomosis (see, e.g.,FIGS. 35 and 35A). As shown inFIG. 34, tissue of graft conduit900adjacent toe916may be pulled into the aortotomy at medial portion1005, below band300, and then back out to a position held between expansion portion310of assembly500and exterior wall1003of conduit1000, whereas tissue of conduit900at heel920may be held at medial portion1005of the aortotomy between ring200and band300. It is to be understood that the cross-sectional area of the ostium of the completed anastomosis between opening911in graft conduit900and aperture1002, as shown inFIGS. 34-35A, is defined by the cross-sectional area of opening125of band124(see, e.g.,FIGS. 10 and 29), which may be larger than that of graft conduit900, as described above.

In another embodiment, aperture1002may be formed by making a round or oval incision in side wall1011of body tissue conduit1000, depending on the shape of opening125of the connector body100being used, for example. This may be accomplished in many ways, including punching an aortotomy, by controlling and cutting aorta tissue in a shape of an oval or circle in a desired manner without having to make a previous incision into the tissue. An aortotomy may also be accomplished by using electric cautery, or ultrasonic or harmonic frequencies to generate a hole in the tissue of a desired and controlled shape such as an oval.

FIGS. 36 and 37show a device1100that is able to provide an aortotomy in yet another way, by rotating a tube1110having a cutting edge1120in direction1113through a given trajectory created by a mandrel1130within tube1110. Mandrel1130may be round, oval, or any other similar shape. The driving of the preferably thin-walled material of cutting edge1120(e.g., nitinol or stainless steel) through the given geometry of mandrel1130creates a path and subsequently a hole of the given shape which is not necessarily round.

In yet another embodiment, aperture1002may be formed by making an incision of a controlled, predetermined length in the side wall of body tissue conduit1000(e.g., as in U.S. patent application Ser. No. 10/678,403, filed Oct. 4 2003, which is hereby incorporated by reference herein in its entirety).

In another preferred embodiment of the connector assembly of the present invention,FIG. 38shows a planar development of what is actually, preferably, an integral, one-piece (unitary), annular, cellular connector body2100, similar to connector body100. In particular, the left and right edges of the structure shown inFIG. 38are actually, preferably, joined to and integral with one another. Thus, the actual structure of connector body2100is as shown inFIGS. 39 and 40, althoughFIG. 38is useful to more clearly reveal certain details of various features of connector body2100. A central longitudinal axis2110about which connector body2100is annular is shown inFIGS. 39 and 40.

A particularly preferred material for connector body2100is nitinol. Other examples of suitable materials include tantalum, tungsten, stainless steel, platinum, silicone, and polyurethane. Connector body2100may be advantageously produced by starting with a single, unitary tube, such as a hypotube, and removing selected material until only the structure shown inFIGS. 39 and 40remains. For example, laser cutting may be used to remove material from the starting tube in order to produce connector body2100. After removing the material to form the structure shown inFIG. 38, the machined tube may be placed in a mold and heat-shaped into approximately the geometry that connector body2100will assume after deployment. For example, connector body2100may be heat-shaped into the geometry shown inFIGS. 39 and 40. The shape of connector body2100is retained after removing connector body2100from the mold due to the properties of nitinol.

Like connector body100, connector body2100may be described as including annularly spaced cell portions or inside aortic fingers2112. According to one embodiment, connector body2100includes eight repeating cell portions2112. Connector body2100may have fewer or more than eight of cell portions2112, depending on the axial length and perimeter of the tube used to manufacture connector body2100and the resulting anastomosis ostium desired. Alternatively, the structure of connector body2100may have different configurations of cells and geometries.

Each cell2112includes a pair of annularly spaced members2120. Each cell2112typically also includes a pair of annularly spaced members2122. The proximal end of each member2122is connected to the distal ends of adjacent members2120of adjacent cells2112, and the distal ends of members2122are connected to the proximal portion of an annular element2124. Annular element2124defines the distal portion2114of connector body2100, whereas annularly spaced members2122define the medial portion2116of connector body2100.

The proximal ends of annularly spaced members2120of each cell2112are typically connected to one another at an annularly extending member2126, which is preferably curved proximally. A pair of members2120and a member2126define the proximal portion2118of each cell portion2112.

Some or all of cell portions2112at its distal end may include a tissue holding feature that in this case includes a distal member2134that has a barb-like free end portion2136that is sharply pointed and that points toward proximal portion2118. Distal member2134may be connected to annular element2124. A typical distal member2134may have a length2135in a range from about 0.035 inches to about 0.075 inches. (It should be noted that length2135includes the width of annular element2124.) However, the dimensions of distal member2134may be altered according to the wall thickness of the graft conduit to be loaded thereon. Each of distal members2134is deflectable radially outward from the remainder of the structure of connector body2100, as shown, for example, inFIGS. 39 and 40.

The above-mentioned outward deflection of distal members2134may be produced by putting connector body2100on a mandrel and prying members2134radially outward. Like connector body100, connector body2100may also typically require other processing appropriate for an implantable device such as, for example, polishing, passivation, cleaning, and sterilizing.

As shown in this example, connector body2100preferably has a fixed cross-sectional area. Specifically, annular element2124of distal portion2114is an annular structure having a fixed cross-section, an outer surface2123, an inner surface2121, and an opening2125defined therein, which may be round, oval, or any other substantially smooth shape. In another preferred embodiment, connector body2100may be expandable or enlargeable.

As shown inFIGS. 39 and 40, inside aortic fingers2112may expand radially out from distal portion2114. As described above, fingers2112may expand to this configuration created by heat-shaping connector body2100. The expansion of fingers2112is preferably elastic. One adjacent member2120of each finger2112may be provided with an aortic eyelet2128for interaction with an aortic delivery tool, such as tool700described above, such that proximal portion2118may be configured to pass through an aperture in an aorta, as described above with respect to connector assembly500and aorta1000.

In this embodiment, the end of a graft tissue conduit, such as graft tissue conduit900, may be loaded onto the tissue holding features provided by distal members2134with barb-like free end portions2136of connector body2100. Members2134may penetrate and pass through the side wall of graft conduit900from interior surface901to exterior surface903as a result of, for example, compressing the graft against free end portions2136with a physician's tool (e.g., the vein piercing tool described in Logan et al. U.S. Pat. No. 6,669,256), thereby forcing the free end portions to pierce through the graft wall. The sharpened tips of free end portions2136may facilitate penetration of conduit900, while the blunt rear surfaces thereof may resist withdrawal therefrom, like a barb. Conduit900may be additionally or alternatively directly sutured to connector body2100.

Connector body2100may be loaded into body tissue conduit1000in a way similar to how connector assembly500is attached to body tissue conduit1000(FIGS. 30-35), for example. However, a line or wire2200, as shown inFIG. 41, may be provided to wrap around annular element2124external to graft conduit900once conduit900has been loaded onto connector body2100, for example. Wire2200may form a loop2202for tightly winding around annular element2124, above distal members2134, and may provide ends2201and2203to extend therefrom for contacting exterior wall1003of body conduit1000about aperture1002, as shown inFIGS. 42 and 43, for example, although, in another embodiment, wire2200may similarly form a loop2202for tightly winding around annular element2124, below distal members2134or a weaving combination of above and below distal members2134. Wire2200may also be used with any of the other connector assemblies described herein, instead of or in addition to an outside-the-graft retaining band, either above or below an inside-the-graft retaining ring.

This embodiment of connector body2100, wherein the tissue holding features are provided at annular element2124and can retain a graft conduit thereon may obviate the need for an inside-the-graft retaining ring and/or an outside-the-graft retaining band and collar. As shown inFIG. 42, the sharpened tips of free end portions2136may facilitate penetration of conduit900.

In another preferred embodiment of the connector assembly of the present invention,FIG. 44shows in isolation a substantially annular outside-the-graft retaining element or band3300, similar to band300. Like band300, a particularly preferred material for band3300is nitinol. Other examples of suitable materials include tantalum, tungsten, stainless steel, platinum, silicone, and polyurethane.

Outside-the-graft retaining band3300may generally be described as including a substantially annular element3302with an inner surface3301, whose size and shape, in a preferred embodiment, may match that of outer surface203of annular element202of inside-the-graft retaining ring200(see, e.g.,FIG. 11). Tooth3304is provided at a portion of outer surface3303of element3302and is appropriately placed such that it interacts with a band slot134(see, e.g.,FIG. 8) of connector body100when it is heat treated or bent out of the plane of annular element3302and then parallel thereto, and when band3300is coupled to connector body100, as shown inFIG. 45. Connector body100may be provided with band slot134instead of hinge joint132when band3300is desired to be used instead of band300. Band slot134of connector body100and tooth3304of band3300interact such that band3300may be coupled to connector body100when band3300is positioned in a “closed” position thereabout, as described in more detail below. Connector body2100may also be provided with a band slot2134(see, e.g.,FIG. 38) when band3300is desired to be used instead of, or in addition to, wire2200. Band slot2134of connector body2100and tooth3304of band3300interact such that band3300may be coupled to connector body2100when band3300is positioned in a “closed” position thereabout (see, e.g.,FIG. 46) Band3300may also include one or more outside-the-graft retention features or teeth3308projecting inwardly from inner surface3301of band3300about element3302.

Band3300may also be described as including one or more outside aortic fingers3306, similar to fingers306, projecting outwardly from element3302in substantially the same plane as element3302such that they engage the exterior wall of the aorta when they are bent or heat treated to curve out of the plane and when the anastomosis is completed. According to one embodiment, band3300includes two diametrically spaced outside aortic fingers3306projecting from element3302. Band3300may have fewer or more than two aortic fingers3306, depending on the size and shape of the connector body to be used, for example.

One or more resilient expansion portions3310are included as an integral element of band3300, interrupting substantially annular element3302. According to one embodiment, band3300includes three spaced resilient expansion portions3310. Band3300may have fewer or more than three expansion portions3310, depending on the size and shape of band3300, for example.

Resilient expansion portions3310enable expansion of the size and shape of the opening defined by inner surface3301, thereby allowing band3300to pass beyond outer surface203and flanges206of inside-the-graft retaining ring200(or, in another embodiment, free end portions2136of band2124) while tooth3304may interact with band slot134(e.g., by sliding therein) to maintain the relative positioning of band3300and connector body100(or with band slot2134to maintain the relative positioning of band3300and connector body2100), for example. Thereafter, expansion portions3310enable resilient contraction of inner surface3301substantially to its original size, as described above with respect to band300(see, e.g.,FIGS. 15 and 16), for holding band3300in its closed position along with tooth3304and band slot134/2134, as shown inFIGS. 45 and 46, respectively, wherein outside aortic fingers306/3306are not shown for the sake of clarity. Therefore, once a graft conduit has been loaded onto a connector body of the present invention, band3300may be coupled to the connector body, expanded, and then contracted thereabout in order to hold the graft conduit to the connector assembly, with or without the use of band300and/or wire2200.

It should be noted that, although apparatus and methods for making anastomoses of the present invention have been described as providing outside-the-graft retention features (e.g., wire2200and features308and3308) generally below inside-the-graft retention features (e.g., features208and members2134) about a connector body, the present invention also relates to apparatus and methods for making anastomoses that provide outside-the-graft retention features not only below, but also above and/or at the same elevation as inside-the-graft retention features about a connector body. This may be accomplished with the previously described connector assembly embodiments by altering the relative positioning of hinge132or band slots134/2134and slots130or retention features2134, for example.

As shown inFIG. 47, for example, hinge132′ and band slot134′ of connector body100′ are significantly closer to slots130′ than hinge132and band slot134of connector body100are to slots130(see, e.g.,FIG. 8). This geometry of connector body100′ allows for the retention features of outside-the-graft retaining band300to be at relatively the same elevation as the retention features of inside-the-graft retaining ring200at the heel of graft conduit900, while still allowing the retention features of band300to be below the retention features of ring200at the toe of graft conduit900, as shown inFIG. 48, for example.

As shown inFIGS. 49 and 50, for example, the slots130″ of connector body100″ opposite those adjacent to hinge132″ and band slot134″ are significantly more distal from hinge132″ and band slot134″ than those slots130are from hinge132and band slot134of connector body100(see, e.g.,FIG. 8). This geometry of connector body100″ allows for the retention features of outside-the-graft retaining band300to be even further below the retention features of inside-the-graft retaining ring200at the toe of graft conduit900than at the heel of graft conduit900, as shown inFIG. 50, for example.

A “fixed stenosis” connector configuration refers to the positioning of the graft heel tissue in such a way that it is substantially always at the same position relative to exterior surface of the body tissue conduit, regardless of the body tissue conduit's medial wall thickness. Therefore, the lumen restriction will be of a fixed amount and not dependant on the body tissue conduit thickness.

Torsional components combined with bending members may be provided by any of the above-described connector body configurations to engage a larger range of body tissue conduit thicknesses, by combining the strain levels that each member can undergo before permanent deformation occurs.FIG. 51, for example, shows another preferred embodiment of a connector body of the present invention with such components as a planar development of what is actually, preferably, an integral, one-piece connector body, similar to connector body100(see, e.g.,FIG. 8). As shown, inside aortic fingers112′″ are bending members that may be attached or mounted to annular element124′″ by torsional support members119′″ of connector body100′″. This geometry may allow the active range of motion of the connector assembly to be on the order of magnitudes greater than that of either the bending members or support members alone. Multiple sets of torsional and bending members may be provided to accommodate a large range of aortic tissue thicknesses and to facilitate a seal with a large range of aortic pressures.

Thus it is seen that connectors for creating an aortic anastomosis whose ostium diameter is larger than that of the graft conduit and methods of use have been provided. One skilled in the art will appreciate that the present invention can be practiced by other than the described embodiments, which are presented for purposes of illustration and not of limitation, and the present invention is limited only by the claims which follow.