Abstract:
An anastomosis device may include a central region, and at least one projection connected to the distal end of the central region, where at least one projection is foldable in at least the proximal direction. An anastomosis device may include a central region, and an inner flange connected to the distal end of the central region, the inner flange deployable from a first position to an expanded position, where the inner flange includes at least one substantially triangular inner flange element.

Description:
[0001]    This application is a continuation of U.S. patent application Ser. No. 09/664,588, filed on Sep. 18, 2000, which in turn is a divisional of U.S. Pat. No. 6,428,550, issued on Aug. 6, 2002, all of which are incorporated by reference in their entirety. 
     
    
     
       BACKGROUND  
         [0002]    1. Field of the Invention  
           [0003]    The invention relates to an anastomosis device for forming a sutureless connection between two blood vessels.  
           [0004]    2. Brief Description of the Related Art  
           [0005]    Vascular anastomosis is a procedure by which two blood vessels within a patient are surgically joined together. Vascular anastomosis is performed during treatment of a variety of conditions including coronary artery disease, diseases of the great and peripheral vessels, organ transplantation, and trauma. In coronary artery disease (CAD) an occlusion or stenosis in a coronary artery interferes with blood flow to the heart muscle. Treatment of CAD involves the grafting of a vessel in the form of a prosthesis or harvested artery or vein to reroute blood flow around the occlusion and restore adequate blood flow to the heart muscle. This treatment is known as coronary artery bypass grafting (CABG).  
           [0006]    In the conventional CABG, a large incision is made in the chest and the sternum is sawed in half to allow access to the heart. In addition, a heart-lung machine is used to circulate the patient&#39;s blood so that the heart can be stopped and the anastomosis can be performed. In order to minimize the trauma to the patient induced by conventional CABG, less invasive techniques have been developed in which the surgery is performed through small incisions in the patients chest with the aid of visualizing scopes. Less invasive CABG can be performed on a beating or stopped heart and thus may avoid the need for cardiopulmonary bypass.  
           [0007]    In both conventional and less invasive CABG procedures, the surgeon has to suture one end of the graft vessel to the coronary artery and the other end of the graft vessel to a blood supplying vein or artery, such as the aorta. The suturing process is a time consuming and difficult procedure requiring a high level of surgical skill. In order to perform the suturing of the graft to the coronary artery and the blood supplying artery the surgeon must have relatively unobstructed access to the anastomosis sites within the patient. In the less invasive surgical approaches, some of the major anastomosis sites cannot be easily reached by the surgeon because of their location. This makes suturing either difficult or impossible without opening up the chest cavity.  
           [0008]    An additional problem with CABG is the formation of thrombi and atherosclerotic lesions at and around the grafted artery, which can result in the reoccurrence of ischemia. Thrombi and atherosclerotic lesions may be caused by the configuration of the sutured anastomosis site. For example, an abrupt edge at the anastomosis site may cause more calcification than a more gradual transition. However, the preferred gradual transition is difficult to achieve with conventional suturing methods.  
           [0009]    Accordingly, it would be desirable to provide a sutureless vascular anastomosis device which easily connects a graft to a target vessel. It would also be desirable to provide a sutureless anastomosis device which is formed of one piece and is secured to the target vessel in a single step.  
         SUMMARY OF THE INVENTION  
         [0010]    The present invention relates to an anastomosis device for connecting an end of a graft vessel to a target vessel. The anastomosis includes a first linkage formed of a plurality of struts and a plurality of axial members. The first linkage is expandable from a first configuration in which the first linkage is a substantially cylindrical shape to a second configuration in which the first linkage includes a first radially extending flange. A substantially cylindrical central connecting portion extends from the first linkage. A second linkage is configured to form a second radially extending flange spaced from the first radially extending flange.  
           [0011]    In accordance with an additional aspect of the present invention, an anastomosis device for connecting an end of a graft vessel to a target vessel includes an expandable device formed from a plurality of struts and deformable from a first configuration in which the device is substantially tubular to a second configuration in which the device includes a first radial flange and a second radial flange spaced from the first radial flange a distance sufficient to accommodate a wall of a blood vessel. A first end of the expandable device includes a first linkage which changes from a substantially tubular configuration to a radially extending configuration to form the first flange upon radial expansion of the first end by an expander positioned in a center of the expandable device. A second end of the expandable device includes a second linkage which is configured to form the second radial flange upon deployment of the device.  
           [0012]    In accordance with another aspect of the present invention, a method of performing anastomosis includes the steps of providing a one-piece tubular anastomosis device; everting an end of a graft vessel around the anastomosis device; puncturing a target vessel with a trocar; inserting the tubular anastomosis device with everted graft vessel into the puncture in the target vessel; radially expanding the tubular anastomosis device with an expander to cause portion of the tube to fold outward forming a first annular flange; and forming a second annular flange on the anastomosis device to trap a wall of the target vessel between the first and second annular flanges and seal the graft vessel to the target vessel.  
           [0013]    In accordance with a further aspect of the present invention, an anastomosis device deployment system includes a handle, a holder tube attached to the handle, and an expander positioned within the holder and slidable with respect to the holder to a position at which the expander is positioned within the anastomosis device to radially expand the anastomosis device. The holder tube has a distal end configured to hold the anastomosis device with an attached graft vessel. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]    The invention will now be described in greater detail with reference to the preferred embodiments illustrated in the accompanying drawings, in which like elements bear like reference numerals, and wherein:  
         [0015]    [0015]FIG. 1 is a perspective view of a first embodiment of an anastomosis device in a configuration prior to use with a graft vessel everted over the device;  
         [0016]    [0016]FIG. 2 is a perspective view of the anastomosis device of FIG. 1 in a deployed configuration;  
         [0017]    [0017]FIG. 3 is a perspective view of a second embodiment of an anastomosis device in a configuration prior to use with a graft vessel everted over the device;  
         [0018]    [0018]FIG. 4 is a perspective view of the anastomosis device of FIG. 3 in a deployed configuration;  
         [0019]    [0019]FIG. 5 is a perspective view of a third embodiment of an anastomosis device in a configuration prior to use with a graft vessel everted over the device;  
         [0020]    [0020]FIG. 6 is a perspective view of the anastomosis device of FIG. 5 in a deployed configuration;  
         [0021]    [0021]FIG. 7 is a perspective view of a fourth embodiment of an anastomosis device in a configuration prior to use with a graft vessel everted over the device;  
         [0022]    [0022]FIG. 8 is a perspective view of the anastomosis device of FIG. 7 in a deployed configuration;  
         [0023]    [0023]FIG. 9 is a perspective view of a fifth embodiment of an anastomosis device in a configuration prior to use with a graft vessel everted over the device;  
         [0024]    [0024]FIG. 10 is a perspective view of the anastomosis device of FIG. 9 with a bottom flange in a deployed configuration;  
         [0025]    [0025]FIG. 11 is a perspective view of the anastomosis device of FIG. 9 with a bottom flange and a top flange both in deployed configurations;  
         [0026]    [0026]FIG. 12 is a side view of a portion of a sixth embodiment of an anastomosis device which has been laid flat for ease of illustration;  
         [0027]    [0027]FIG. 13 is a side view of a portion of a seventh embodiment of an anastomosis device which has been laid flat for ease of illustration;  
         [0028]    [0028]FIG. 14 is a perspective view of an anastomosis device deployment system;  
         [0029]    [0029]FIG. 14A is an enlarged perspective view of the distal end of the anastomosis device deployment system of FIG. 14 with an anastomosis device prior to deployment;  
         [0030]    [0030]FIG. 15 is a side cross sectional view of the anastomosis device deployment system puncturing the target vessel to advance the anastomosis device into the target vessel wall;  
         [0031]    [0031]FIG. 16 is a side cross sectional view of the anastomosis device deployment system advancing the anastomosis device into the target vessel wall;  
         [0032]    [0032]FIG. 17 is a side cross sectional view of the anastomosis device deployment system with an expanded first annular flange;  
         [0033]    [0033]FIG. 18 is a side cross sectional view of the anastomosis device deployment system expanding a second annular flange;  
         [0034]    [0034]FIG. 19 is a schematic side cross-sectional view of a deployment tool taken along line A-A of FIG. 14, the deployment tool is shown during a vessel puncturing step;  
         [0035]    [0035]FIG. 20 is a schematic side cross-sectional view of the deployment tool of FIG. 19 shown during an anastomosis device insertion step;  
         [0036]    [0036]FIG. 21 is a schematic side cross-sectional view of the deployment tool of FIG. 19 shown during an anastomosis device expansion step;  
         [0037]    [0037]FIG. 22 is a schematic side cross-sectional view of the deployment tool of FIG. 19 shown after the anastomosis device has been fully deployed;  
         [0038]    [0038]FIG. 23 is a perspective view of a eighth embodiment of an anastomosis device in a configuration prior to use;  
         [0039]    [0039]FIG. 23A is a side view of a portion of the anastomosis device of FIG. 23 prior to folding a tab of the device inward;  
         [0040]    [0040]FIG. 24 is a perspective view of the anastomosis device of FIG. 23 in a deployed configuration;  
         [0041]    [0041]FIG. 25 is a side view of a portion of a ninth embodiment of an anastomosis device which has been laid flat for ease of illustration;  
         [0042]    [0042]FIG. 26 is a side view of a portion of a tenth embodiment of an anastomosis device which has been laid flat for ease of illustration;  
         [0043]    [0043]FIG. 27 is a side view of a portion of an eleventh embodiment of an anastomosis device which has been laid flat for ease of illustration;  
         [0044]    [0044]FIG. 28 is a side view of an eleventh embodiment of an anastomosis device which has been laid flat for ease of illustration; and  
         [0045]    [0045]FIG. 29 is a top view of the anastomosis device of FIG. 28 with a flange deployed.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0046]    The present invention relates to an anastomosis device and method for connecting a graft vessel to a target vessel without the use of conventional sutures. The anastomosis device according to the present invention can be deployed with a deployment system which greatly increases the speed with which anastomosis can be performed over prior art suturing methods. In addition, the anastomosis device provides a smooth transition between the graft vessel and the target vessel. The devices according to the present invention are particularly designed for use in connecting graft vessels to blood delivery or target vessels. Suturing a graft vessel to a target vessel is difficult with conventional techniques, particularly in minimally invasive procedures where space may be limited. However, with an anastomosis device and deployment system of the present invention, anastomosis can be performed efficiently and effectively in tight spaces.  
         [0047]    [0047]FIG. 1 illustrates an anastomosis device  10  according to a first embodiment of the present invention. The anastomosis device  10  includes a plurality of axial members  12  and a plurality of struts  14  interconnecting the axial members. The axial members  12  and struts  14  form a first linkage  16  at a first end of the device and a second linkage  18  at a second end of the device. The first and second linkages  16 ,  18  form first and second flanges  20 ,  22  when the anastomosis device  10  is deployed as illustrated in FIG. 2. The deployed flanges  20 ,  22  may be annular ring shaped or conical in shape. The first and second linkages  16 ,  18  are connected by a central connecting portion  24 .  
         [0048]    In use, a graft vessel  30  is inserted through a center of the tubular anastomosis device  10  and is everted over the first linkage  16  at the first end of the device. The first end of the device may puncture part way or all the way through the graft vessel wall to hold the graft vessel  30  on the device. An opening  34  is formed in the target vessel  32  to receive the graft vessel  30  and anastomosis device  10 . Once the anastomosis device  10  with everted graft vessel  30  are inserted through the opening  34  in the target vessel  32 , the first and second flanges  20 ,  22  are formed as shown in FIG. 2 to secure the graft vessel to the target vessel by trapping the wall of the target vessel between the two flanges. The anastomosis device  10  forms a smooth transition between the target vessel  32  and the graft vessel  30  which helps to prevent thrombi formation.  
         [0049]    The first and second flanges  20 ,  22  are formed by radial expansion of the anastomosis device  10  as follows. The first and second linkages  16 ,  18  are each made up of a plurality of axial members  12  and struts  14 . The struts  14  are arranged in a plurality-of diamond shapes with adjacent diamond shapes connected to each other to form a continuous ring of diamond shapes around the device. One axial member  12  extends through a center of each of the diamond shapes formed by the struts  14 . A reduced thickness section  26  or hinge in each of the axial members  12  provides a location for concentration of bending of the axial members. When an expansion member such as a tapered rod or an inflatable balloon is inserted into the tubular anastomosis device  10  and used to radially expand the device, each of the diamond shaped linkages of struts  14  are elongated in a circumferential direction causing a top and bottom of each of the diamond shapes to move closer together. As the top and bottom of the diamond shapes move closer together, the axial members  12  bend along the reduced thickness sections  26  folding the ends of the device outward to form the first and second flanges  20 ,  22 . Once the first and second flanges  20 ,  22  have been formed, the wall of the target vessel  32  is trapped between the flanges and the everted graft vessel  30  is secured to the target vessel.  
         [0050]    In the anastomosis device  10  shown in FIGS. 1 and 2, the struts  14  may be straight or curved members having constant or varying thicknesses. In addition, the axial members  12  may have the reduced thickness sections  26  positioned at a center of each of the diamond shapes or off center inside the diamond shapes. The positioning and size of the reduced thickness sections  26  will determine the location of the flanges  20 ,  22  and an angle the flanges make with an axis of the device when fully deployed. A final angle between the flanges  20 ,  22  and longitudinal axis of the device  10  is about 40-100 degrees, preferably about 50-90 degrees.  
         [0051]    [0051]FIG. 3 illustrates a second embodiment of a tubular anastomosis device  40  formed of a plurality of struts  42  interconnected in a diamond pattern. A first end of the device includes a plurality of interior diamonds  44  positioned within the diamonds formed by the plurality of struts  42 . When the device is deployed, as illustrated in FIG. 4, the interior diamonds  44  fold outward to form a first annular flange  46 . A second end of the device  40  includes a plurality of pull tabs  48  each having a T-shaped end  50  to be received in a corresponding slot in a deployment device. The deployment device holds the anastomosis device  40  during positioning and deployment of the first flange  46 . Once the first annular flange  46  has been formed, the pull tabs  48  are folded radially outward and downward in the direction of the arrows B to form a second annular flange (not shown). Although the pull tabs  48  have been illustrated with T-shaped ends, the pull tabs may have other configurations such as loops which engage hooks of a deployment device.  
         [0052]    In use, the graft vessel  30  is inserted through a center of the tubular anastomosis device  40  and everted over the first end of the device as shown in FIG. 3. An opening  34  is formed in the target vessel  32  and the anastomosis device  40  with the everted graft vessel  30  are inserted through the opening  34  in the target vessel. An expander is then advanced axially through the anastomosis device  40  to radially expand the device and cause the deployment of the first annular flange  46 . During advancement of the expander, the device  40  is held in place by the deployment device which is connected to the T-shaped ends  50  of the pull tabs  48 . After deployment of the first annular flange  46  the expander is removed and the pull tabs  48  are disconnected from the deployment device and folded outward in the direction of the arrows B in FIG. 4 to form the second annular flange. The wall of the target vessel  32  is trapped between the first and second annular flanges.  
         [0053]    In the embodiment of FIGS. 3 and 4, the interior diamonds  44  which form the first annular flange  46  each include top and bottom reduced thickness connection members  54  which connect the interior diamonds  44  to the struts  42 . Each of the interior diamonds  44  also include a U-shaped web member  56  and two reduced thickness portions  58  located at opposite sides of the interior diamonds. As the device  40  is radially expanded, the diamond shapes formed by the struts  42  become more elongated in a circumferential direction, shortening the height of each of these diamond shapes. As the height of the diamond shapes formed by the struts  42  decreases, the interior diamonds  44  are folded outward into the configuration illustrated in FIG. 4. When the device  40  is fully expanded and the first annular flange  46  is fully formed, the diamonds which originally surrounded the interior diamonds  44  are completely extended and the struts  42  which originally formed the diamonds are parallel or substantially parallel. The interior diamonds  44  are each folded in half at the reduced thickness portions  58  or hinges.  
         [0054]    [0054]FIGS. 5 and 6 illustrate a third embodiment of a tubular anastomosis device  60  having a plurality of struts  62 , interior diamonds  64 , and a plurality of pull tabs  68 . The anastomosis device  60  of FIGS. 5 and 6 differs from the anastomosis device  40  of FIGS. 3 and 4 in the arrangement of the interior diamonds  64 . The interior diamonds  64 , as illustrated in FIG. 5, are connected to the surrounding struts  62  by three connection members  70 . The connection members  70  are located at opposite sides of each of the interior diamonds  64  and at the bottom of the interior diamonds. A top-corner  72  of each of the interior diamonds  64  is not connected to the struts and folds inward upon expansion of the device.  
         [0055]    With this embodiment of FIGS. 5 and 6, as an expander is inserted axially through the anastomosis device  60 , the top corners  72  of each of the interior diamonds  64  fold inwardly while a bottom edge of the device folds outwardly to form the first annular flange  66 . The expander may also push on the inwardly folded top corners  72  of the interior diamonds  64  to further bend the first flange  66  outward. The device  60  also includes a plurality of pointed ends  74  which puncture the everted graft vessel  30  and help to retain the graft vessel on the anastomosis device  60 .  
         [0056]    In use, the anastomosis device  60  is provided with a graft vessel  30  which is inserted through a center of the device and everted over the pointed ends  74  and interior diamonds  64  of the device. The anastomosis device  60  and everted graft vessel  30  are then inserted in the opening  34  in the target vessel  32  and the first annular flange  66  is deployed by expansion of the device with an axially movable expander. After formation of the first annular flange  66 , the pull tabs  68  are folded downward and outward in the direction of the arrows B illustrated in FIG. 6 to form the second annular flange and trap the wall of the target vessel between the first and second annular flanges.  
         [0057]    An alternative embodiment of an anastomosis device  80  illustrated in FIGS. 7 and 8 includes two rows of diamond-shaped members  82  which fold outward to form the first and second annular flanges  84 ,  86 . Each of the diamond-shaped members  82  is connected to M-shaped struts  88  at one end and to V-shaped struts  90  at an opposite end. The diamond-shaped members  82  are connected only at the top end and bottom end. A central connecting portion  92  of the device  80  includes a plurality of large diamond-shaped support members  94 . As an expander is inserted into the device  80 , the device expands from a configuration illustrated in FIG. 7 to the configuration illustrated in FIG. 8 in which the first and second annular flanges  84 ,  86  have been formed. During expansion, the M-shaped struts  88  and the V-shaped struts  90  are extended to straight or substantially straight members and the large diamond support members  94  move away from one another. The diamond-shaped members  82  each fold in half at reduced thickness portions  96  as in the embodiment illustrated in FIGS. 3 and 4.  
         [0058]    [0058]FIGS. 9-11 illustrate a further alternative embodiment of an anastomosis device  100  according to the present invention. The device  100  includes a plurality of axial members  102  having reduced thickness portions  104 . Each of the axial members  102  is positioned within a multi-sided expandable linkage  106 . A central connecting portion  108  connects the expandable linkage  106  to a plurality of pull tabs  110 . Each of the pull tabs  110  has a T-shaped end  112  which is received in a corresponding slot in a deployment device to hold the anastomosis device  100  during insertion and expansion. However, other pull tab shapes may also be used. As an expander is inserted axially into the anastomosis device  100 , the linkage  106  expands causing the axial members  102  to fold along the reduced thickness portions  104  and extend radially outward forming a first radial flange  114 , as illustrated in FIG. 10. The first radial flange  114  may be configured to extend at an acute angle from an axis of anastomosis device  100  or may be folded to form an angle of up to 90 degrees or greater. The angle between the axis of anastomosis device and the lower portion of the axial members  102  after the first radial flange  114  has been deployed is preferably between about 40 and 100 degrees. After the first radial flange has been deployed, the pull tabs  110  are disengaged from the deployment device and folded outwards in the direction of the arrows B to form a second radial flange  116  as illustrated in FIG. 11. To disengage and fold the pull tabs  110  outwards, the deployment device is moved distally with respect to the anastomosis device. The first and second radial flanges  114 ,  116  trap a wall of the target vessel  32  between the flanges and thus secure the everted graft vessel  30  to the target vessel.  
         [0059]    [0059]FIGS. 12 and 13 illustrate alternative embodiments of the device  100  of FIGS. 9 through 11. The expandable tubular anastomosis device  120  of FIG. 12 has been cut and laid flat for ease of illustration. The device  120  includes a plurality of axial members  122  having hinges  124  in the form of U-shaped grooves. The axial members  122  are each mounted at opposite ends in an expandable linkage  126 . The expandable linkage  126  is at one end of the device  120  while an opposite end of the device includes a plurality pull tabs  130 . The pull tabs  130  and linkage  126  are connected by a central connecting portion  128 . Each of the pull tabs  130  has a T-shaped end  132 , a shoulder  134 , and a triangular slot  136 . Extending from an end of each of the pull tabs  130  opposite the T-shaped ends  132  is a tab lock  138 .  
         [0060]    In use, the anastomosis device  120  of FIG. 12 is used in a manner substantially similar to that of the device shown in FIGS. 9-11. In particular, the device  120  is attached to an deployment tool by the T-shaped ends  132  of the pull tabs  130 . A graft vessel is extended through the center of the tubular device  120  and everted around the end of the device opposite the pull tabs  130 . An expander is advanced axially into the device to expand the expandable linkage  126  and cause the lower portion of each of the axial members  122  below the hinges  124  to bend outward to form a first flange. The material in the center of each of the U-shaped cuts which form the hinges  124  serves as a backstop to prevent the flange from bending or rolling due to radial compressive forces applied to the flange by the stretched graft vessel. In contrast, with the narrowed section hinge shown in FIG. 1 the bend at the hinge tends to roll away from the desired hinge point due to compressive forces applied by the graft vessel. The backstop hinge  124  prevents rolling of the bend along the axial member  122 .  
         [0061]    After formation of the first flange with the expander, the expander is withdrawn. During this withdrawal of the expander, an annular groove on an exterior surface of the expander engages the tab locks  138  causing the pull tabs  130  to bend outwardly to form the second flange. Alternatively, the tab locks  138  may be caught on a leading edge of the expander. As the pull tabs  130  bend outwardly, the T-shaped ends  132  of the pull tabs disengage from the deployment device. According to one embodiment of the invention, the second flange is formed by a first bend in the pull tabs  130  at a location between the triangular slot  136  and the lock tab  138  and a second bend in the pull tab at the shoulder  134 . These two bends in the pull tabs  130  allow the anastomosis device to accommodate target vessels with different wall thicknesses. Each of the two bends preferably forms an angle of about 20-70 degrees.  
         [0062]    [0062]FIG. 13 illustrates a further embodiment of a tubular anastomosis device  120 ′ which corresponds substantially to the device shown in FIG. 12. However, FIG. 13 illustrates several different variations of hinges  124 ′ for the axial members  122 ′. In particular, the hinges  124 ′ may be formed in any of the different manners illustrated in FIG. 13 by removing material from the axial members  122 ′ to cause bending at the desired location. These hinges  124 ′ may include openings of various shapes and/or cut away portions on the sides of the axial members  122 ′. The different hinge configurations have been shown in one device only for purposes of illustration.  
         [0063]    [0063]FIGS. 14-18 illustrate a deployment system  150  and sequence of deploying an anastomosis device  120  such as the device shown in FIG. 12 with the deployment system. In FIGS. 14-16 the graft vessel  30  has been eliminated for purposes of clarity. As shown in FIGS. 14-18, the deployment system  150  includes a hollow outer trocar  152  (not shown in FIG. 14), a holder tube  154  positioned inside the trocar, and an expander tube  156  slidable inside the holder tube. As can be seen in the detail of FIG. 14A, the anastomosis device  120  is attached to a distal end of the holder tube  154  by inserting the T-shaped ends  112  of each of the pull tabs  110  in slots  158  around the circumference of the holder tube. The trocar  152 , holder tube  154 , and expander tube  156  are all sidable with respect to one another during operation of the device. A device handle  160  is provided for moving the tubes with respect to one another will be described in further detail below with respect to FIGS. 19-22.  
         [0064]    As shown in FIG. 15, initially, the holder tube  154 , expander tube  156 , and the anastomosis device  120  are positioned within the trocar  152  for insertion. The trocar  152  has a hollow generally conical tip with a plurality of axial slots  162  which allow the conical tip to be spread apart so that the anastomosis device  120  can slide through the opened trocar. The trocar  152 , acting as a tissue retractor and guide, is inserted through the wall of the target vessel  32  forming an opening  34 . As shown in FIG. 16, the anastomosis device  120  is then advanced into or through the target vessel wall  32  with the holder tube  154 . The advancing of the holder tube  154  causes the distal end of the trocar  152  to be forced to spread apart. Once the anastomosis device  120  is in position and the trocar  152  has been withdrawn, the first annular flange is deployed by advancing the expander tube  156  into the anastomosis device. The advancing of the expander tube  156  increases the diameter of the anastomosis device  120  causing the first flange to fold outward from the device. This expanding of the first flange may be performed inside the vessel and then the device  120  may be drawn back until the flange abuts an interior of the target vessel wall  32 .  
         [0065]    As shown in FIG. 18, after the first flange has been deployed, the expander tube  156  is withdrawn forming the second flange. As the expander tube  156  is withdrawn, the anastomosis device  120  drops into a radial groove  157  on an exterior of the expander tube due to the elasticity of the device. The radial groove  157  holds the anastomosis device  120  stationary on the expander tube. The holder tube  154  is then moved forward disengaging the anastomosis device pull tabs  130  from the slots  158  in the holder tube. The shoulders  134 , shown most clearly in FIGS. 15 and 16, engage a tapered distal end of the holder tube  154  causing the pull tabs  130  to be released from the slots  158 . As the holder tube  154  is moved further forward, the holder tube causes the second flange to be deployed. The edges of the radial groove  157  are preferably beveled so that the anastomosis device  120  will be able to be removed from the expander tube  156  after the anastomosis device is completely deployed.  
         [0066]    One alternative embodiment of the holder tube  154  employs a plurality of flexible fingers which receive the pull tabs  130  of the anastomosis device  120 . According to this embodiment each pull tab  130  is received by an independent finger of the holder tube  154 . To deploy the second or outer flange of the anastomosis device  120 , the flexible fingers flex outward bending the pull tabs  130  outward.  
         [0067]    [0067]FIGS. 19-22 illustrate the operation of the handle  160  to move the trocar  152 , the holder tube  154 , and the expander tube  156  with respect to one another to deploy the anastomosis device  120  according to the present invention. The handle  160  includes a grip  170  and a trigger  172  pivotally mounted to the grip at a pivot  174 . The trigger  172  includes a finger loop  176  and three contoured cam slots  178 ,  180 ,  182  corresponding to the trocar  152 , holder tube  154 , and expander tube  156 , respectively. Each of these tubes has a fitting  184  at a distal end thereof. A pin  186  connected to each of the fittings  184  slides in a corresponding one of the cam slots  178 ,  180 ,  182 . A fourth cam slot and tube may be added to control deployment of the second flange.  
         [0068]    The handle  160  is shown in FIG. 18 in an insertion position in which the trocar  152  extends beyond the holder tube  154  and the expander tube  156  for puncturing of the target vessel wall  32 . As the trigger  172  is rotated from the position illustrated in FIG. 19 to the successive positions illustrated in FIGS. 20-22, the pins  186  slide in the cam slots  178 ,  180 ,  182  to move the trocar  152 , holder tube  154  and expander tube  156 .  
         [0069]    [0069]FIG. 20 shows the handle  160  with the trigger  172  rotated approximately 30 degrees from the position of FIG. 19. This rotation moves the holder tube  154  and expander tube  156  forward into the wall of the target vessel  32  spreading the trocar  152 . The anastomosis device  120  is now in position for deployment. FIG. 21 shows the trigger  172  rotated approximately 45 degrees with respect to the position of FIG. 19 and the cam slot  182  has caused the expander tube  156  to be advanced within the holder tube  154  to deploy the first flange. The trocar  152  has also been withdrawn.  
         [0070]    [0070]FIG. 22 shows the handle  160  with the trigger  172  pivoted approximately 60 degrees with respect to the position shown in FIG. 19. As shown in FIG. 22, the expander tube  156  has been withdrawn to pull the first flange against the vessel wall  32  and the holder tube  154  is moved forward to deploy the second flange and disengage the holder tube  154  from the anastomosis device  120 .  
         [0071]    The handle  160  also includes a first channel  188  and a second channel  190  in the grip  170  through which the graft vessel (not shown) may be guided. The grip  170  also includes a cavity  192  for protecting an opposite end of the graft vessel from the attachment end.  
         [0072]    [0072]FIG. 23-26 illustrate a further alternative embodiment of the anastomosis device according to the present invention. As shown in FIG. 23, an anastomosis device  200  includes a plurality of pull tabs  202 , a diamond linkage  204 , and a plurality of needles  206 . As shown in the detail of FIG. 23A, each of the needles  206  has a tail portion  208  which is bent radially inwardly as shown in FIG. 23 prior to use. In this embodiment, the graft vessel is inserted through the center of the anastomosis device  200  and everted over the needles  206  as in the previous embodiments. The needles  206  puncture the graft vessel and securely retain the graft vessel on the anastomosis device. To deploy the device  200  of FIG. 23, an expander  210  is inserted axially into the device in a direction of the arrow C and engages the tail portions  208  of the needles  206  to fold the needles radially outward. The expander  210  is preferably larger in diameter than an original inner diameter of the device  200  such that the device is expanded during deployment. This expansion will stretch the opening in the target vessel  32  providing a better seal between the graft and target vessels. However, it should be understood that an outer diameter of the expander  210  according to this embodiment can be equal to or smaller than an inner diameter of the device  200  and can bend the needles  206  outward without radially expanding the device.  
         [0073]    [0073]FIG. 24 illustrates the device  200  of FIG. 23 in which the expander has been used to radially expand the device and bend the needles  206  outward. The pull tabs  202  are then folded downward to trap the wall of the target vessel  32  between the needles  206  and the pull tabs.  
         [0074]    [0074]FIGS. 25 and 26 illustrate two modified versions of the embodiment of FIG. 23. The variations of FIGS. 24 and 25 each include pull tabs  202 , diamond linkages  204 , and needles  206  having tail portions  208  bent inwardly. FIG. 25 and  26  also illustrate horns  212  which help to retain the graft vessel after eversion.  
         [0075]    A cantilevered end of each of the axial members may be either rounded as shown in FIGS. 12 and 13 or pointed as shown in FIGS. 1, 2,  5  and  6 . The rounded cantilever ends prevent puncturing of the graft vessel while the pointed cantilever ends puncture through the vessel and prevent the vessel from slipping off of the anastomosis device. The puncturing of the vessel also relieves stresses on the vessel which are created when expanding the first flange. Although the pointed cantilever ends may provide more secure retention of the graft vessel, these pointed ends will provide undesirable metal within the bloodstream.  
         [0076]    [0076]FIG. 27 illustrates a modified version of the anastomosis device of FIG. 12 in which the anastomosis device  120 ″ includes modified needles  206 ′ with saw tooth edges for grasping tissue of the graft vessel. This version of the anastomosis device  120 ″ also includes backstop hinges  124  and pull tabs  130 .  
         [0077]    [0077]FIGS. 28 and 29 illustrate an alternative embodiment of an anastomosis device  220 . Having the first flange formed from a plurality of members  222  which fold out tangentially from a body of the anastomosis device. The device  220  includes pull tabs  224 , connected by a diamond linkage  226  to the members  222 . As the diamond linkage  226  is expanded in the manner described above with respect to the earlier embodiments, the members  222  fold outward in a direction which is substantially tangential to a body of the expanding device as shown in FIG. 28. The tangentially folded members  222  form the inner flange of the device  220 . The pull tabs  224  are then folded downward to form the outer flange. According to this embodiment of the invention, a second flange may also be formed from a plurality of members which fold out tangentially from a body of the anastomosis device.  
         [0078]    Each of the anastomosis devices described above are preferably single piece devices which are formed by laser cutting or punching from a tube or sheet of material. The devices may be provided in varying sizes to join vessels of different sizes. The linkages, pull tabs, and other elements which have been discussed above with regard to the various embodiments may be used in varying numbers and arrangements.  
         [0079]    The invention has been described as an anastomosis device which is expanded with an expander. The expander may be a tube, a balloon, or any other known expanding device.  
         [0080]    Although the invention has been principally discussed with respect to coronary bypass surgery, the anastomosis devices of the present invention may be used in other types of anastomosis procedures. For example, the anastomosis device may be used in femoral-femoral bypass, vascular shunts, subclavian-carotid bypass, organ transplants, and the like.  
         [0081]    The anastomosis devices may be made of any known material which can be bent and will retain the bent shape such as stainless steel, nickel titanium alloys, and the like. The hinges or pivot joints which have been discussed above in the various embodiments of the present invention are designed to concentrate the bending at a desired location. For example, the hinges may be formed with a reduced thickness or width, or with openings in order to concentrate the bending in the hinges.  
         [0082]    The dimensions of the anastomosis device of the present invention are determined by the dimensions of the blood vessels to be joined. A distance between the two flanges is designed to accommodate the wall thickness of a target vessel which may vary. The anastomosis devices according to the present invention have been illustrated as cylindrical members. However, the devices may also be shaped into oval shapes, football shapes, or other shapes to accommodate smaller target vessels.  
         [0083]    While the invention has been described in detail with reference to the preferred embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made and equivalents employed, without departing from the present invention.