Abstract:
An anastomosis device may include an outer loop and an inner loop connected to and substantially concentric with the inner loop. The outer loop and the inner loop may be connected by at least one hinge. At least one of the outer loop and the inner loop may be movable relative to the other along an axis defined by at least one hinge.

Description:
[0001]     This patent application is a divisional of U.S. patent application Ser. No. 10/331,356, filed on Dec. 20, 2002, which in turn is a continuation of U.S. Pat. No. 6,537,287, which in turn is a continuation of U.S. Pat. No. 6,179,849, all of which are hereby incorporated by reference in their entirety. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The invention relates to an anastomosis device and method, and more particularly, the invention relates to an anastomosis device for forming a sutureless connection between a bypass graft and a blood vessel.  
         [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 patient&#39;s 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. 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 site within the patient. In the less invasive surgical approaches, some of the major coronary arteries cannot be easily reached by the surgeon because of their location. This makes suturing either difficult or impossible for some coronary artery sites. In addition, some target vessels, such as heavily calcified coronary vessels, vessels having very small diameter, and previously bypassed vessels may make the suturing process difficult or impossible.  
         [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. The 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.  
         [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 of a graft vessel to a target vessel. The device includes at least two spreading members being substantially in a plane in an undeployed state. The spreading members move out of the plane to support an opening in a target vessel in a deployed state.  
         [0011]     In accordance with an additional aspect of the present invention, an anastomosis device for connecting a graft vessel to a target vessel includes a frame for receiving and holding a graft vessel, and first and second spreading members configured to be inserted into a target vessel. At least one of the spreading members is movably connected to the frame and allows movement of the spreading members with respect to each other. The frame is deformable and deformation of the frame moves the spreading members.  
         [0012]     According to a further aspect of the invention, an anastomosis device for connecting a graft vessel to a target vessel includes a frame for receiving and holding a graft vessel, and first and second spreading members configured to be inserted into a target vessel. At least one of the spreading members is movably connected to the frame and allows movement of the spreading members with respect to each other. Features are provided on the spreading members for moving the spreading members with respect to the frame.  
         [0013]     In accordance with another aspect of the invention, an anastomosis device for connecting a graft vessel to a target vessel includes a frame for receiving and holding a graft vessel, and first and second spreading members configured to be inserted into a target vessel. At least one of the spreading members is movably connected to the frame allows movement of the spreading members with respect to each other. The frame includes features for deforming the frame to move the spreading members.  
         [0014]     In accordance with another aspect of the invention, an anastomosis device for connecting a graft vessel to a target vessel includes a plurality of linkages arranged in two rows for grasping opposite sides of an opening in the target vessel. Each of the plurality of linkages include a plurality of angled struts surrounding a bendable central strut. Two end members are connected to opposite ends of the two rows which when moved away from one another expand the linkages and cause the bendable central struts to bend, folding a portion of the linkages outward to trap vessel walls on opposite sides of the opening in the target vessel.  
         [0015]     In accordance with another aspect of the present invention, a method of performing anastomosis includes the steps of providing a one-piece anastomosis device, everting an end of a graft vessel around a first portion of the anastomosis device, inserting a second portion of the anastomosis device into an opening in a side wall of a target vessel, and pivoting the first portion with respect to the second portion to capture edges of the opening in the target vessel with the anastomosis device such that a fluid passage is established between the graft and the target vessel.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]     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:  
         [0017]      FIG. 1  is a perspective view of a first embodiment of an anastomosis device in a configuration prior to use;  
         [0018]      FIG. 2  is a top view of a preformed blank for forming the anastomosis device of  FIG. 1 ;  
         [0019]      FIG. 3  is a perspective view of the anastomosis device of  FIG. 1  with a partially cut away graft vessel wrapped around the device and the device fingers inserted into an opening in the target vessel;  
         [0020]      FIG. 4  is a perspective view of the anastomosis device of  FIG. 1  with the fingers spread to secure the graft vessel to the target vessel;  
         [0021]      FIG. 5  is a perspective view of an alternative embodiment of an anastomosis device prior to use;  
         [0022]      FIG. 6  is a top view of a preformed blank from which the anastomosis device of  FIG. 5  is formed;  
         [0023]      FIG. 7  is a perspective view of the anastomosis device of  FIG. 5  with the a partially cut away graft vessel wrapped around the device and the device being inserted into an opening in the target vessel;  
         [0024]      FIG. 8  is a perspective view of the anastomosis device of  FIG. 5  securing a graft vessel to a target vessel;  
         [0025]      FIG. 9  is a perspective view of another alternative embodiment of an anastomosis device prior to use;  
         [0026]      FIG. 10  is a perspective view of the anastomosis device of  FIG. 9  secured to the target vessel with the graft vessel omitted for clarity;  
         [0027]      FIG. 11  is a perspective view of a further alternative embodiment of an anastomosis device prior to use;  
         [0028]      FIG. 12  is a perspective view of an anastomosis device of  FIG. 12  in a closed position in which the device is used to connect a graft vessel to a target vessel;  
         [0029]      FIG. 13  is a perspective view of an additional embodiment of an anastomosis device with an expandable linkage for deployment shown prior to use; and  
         [0030]      FIG. 14  is a perspective view of the anastomosis device of  FIG. 13  in an expanded position in which the device is used to connect a graft vessel to a target vessel. 
     
    
     DETAILED DESCRIPTION  
       [0031]     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 device according to the present invention 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 small target vessels having relatively small diameters such as the coronary arteries. Suture of these small vessels is difficult with conventional techniques, particularly in minimally invasive procedures where space may be limited. The devices may also be used for connecting graft vessels to larger target vessels.  
         [0032]      FIG. 1  illustrates an anastomosis device  10  according to a first embodiment of the present invention. The anastomosis device  10  includes a frame  12  and a plurality of fingers  14  extending from the frame. In use, an end of a graft vessel is inserted through the center of the device and everted around the frame  12 . The fingers  14  are used as spreading members which are inserted into an opening in the target vessel and pulled away from one another to stretch and capture the edges of the opening in the target vessel.  
         [0033]      FIG. 2  illustrates a blank  20  from which the anastomosis device  10  of  FIG. 1  is formed. The blank includes the frame  12  having two parallel side beams  22  and two parallel end beams  24 . The fingers  14  extend from the side beams  22 . Preferably, the fingers  14  extending from one of the side beams  22  are staggered from the fingers extending from the other side beam as illustrated in  FIG. 2 . The preferred staggered arrangement of the fingers allows the device to be bent so that the fingers  14  extending from one of the side beams  22  extend into a gap between the fingers extending from the opposite side beam. As shown in  FIG. 1 , the free ends of each of the fingers  14  are bent into a J-shaped hook  26  which is used to grasp and spread the edges of an opening formed in a target vessel. The end beams  24  of the anastomosis device  10  are bent into a W-shape having a first bend  28  and a second bend  30 . The first and second bends  28 ,  30  function as pivots or living hinges which allow the fingers  14  extending from the first side beam  22  to spread away from the fingers extending from the second side beam.  
         [0034]      FIG. 3  illustrates the anastomosis device  10  with an end of a graft vessel  34  everted about the frame  12 . Six slots  36  are formed in the graft vessel  34  so that the fingers  14  can extend through the graft vessel when the vessel is everted around the frame  12 . As shown in  FIG. 3 , an end  38  of the graft vessel  34  extends underneath and around the side beams  22  and the end beams  24  of the frame  12 . The J-shaped hooks  26  of the fingers  14  are arranged substantially in a plane and inserted into an opening  40  or incision in the wall of a target vessel  42 . The opening  40  is preferably formed longitudinally along the target vessel  42 .  
         [0035]      FIG. 4  illustrates the completed connection between the graft vessel  34  and the target vessel  42  with the anastomosis device  10 . In particular, the device  10  of  FIG. 3  has been bent so that the side beams  22  are pivoted outward and the angles of the first bend  28  and the second bend  30  are substantially straightened. As the bends  28 ,  30  in the frame  12  are straightened, the J-shaped hooks  26  of the fingers  14  move away from one another and out of the original insertion plane to stretch and capture the edges of the opening  40  in the target vessel  42 . As illustrated in  FIG. 4 , the anastomosis device  10  presses the edges of the graft vessel  34  against an exterior surface of the target vessel  42  around the opening  40  in the side of the target vessel.  
         [0036]     Although the embodiment of  FIGS. 1-4  has been illustrated with three fingers  14  extending from each of the side beams  22 , it should be understood that other numbers of fingers may also be used without departing from the present invention. As illustrated in  FIG. 4 , only a small amount of metal of the anastomosis device comes m contact with the blood. In particular, the fingers  14  extending through the slots  36  in the side walls of the graft vessel  32  come into contact with the blood while the remainder of the anastomosis device is outside of the blood flow area.  
         [0037]     Preferably, the finger linkage anastomosis device of  FIGS. 1-4  is cut from a metal tube such as a steel tube and is then formed into the shape illustrated in  FIG. 1  by bending. The fingers  14  are interlaced and the free ends of the fingers are bent downwards into the J-shaped hooks  26 . The graft vessel  34  is initially pulled between the fingers and pierced by the fingers to form the slots  36 . The end of the graft vessel  34  is wrapped around the frame  12 . To attach the graft vessel  34  to the target vessel  42 , the J-shaped hooks  26  are inserted into the incision  40  in the target vessel. When the side beams  22  are rotated outwards, the J-shaped hooks  26  open the incision  40  in the target vessel  42  and secure the graft vessel  34  to the target vessel. Rotation of the side beams  22  of the frame  12  causes plastic deformation of the anastomosis device primarily at the first and second bends  28 ,  30  and seals the graft vessel  34  against the exterior of target vessel  42 .  
         [0038]      FIG. 5  illustrates an alternative embodiment of an anastomosis device  50  having a single scissor configuration. The anastomosis device  50  according to  FIG. 5  includes an inner loop  52  connected to an outer loop  54  by two hinges  56 .  
         [0039]      FIG. 6  illustrates a flat plan view of a blank  60  for forming the anastomosis device  50 . The blank  60  includes the inner loop  52  and the outer loop  54  connected by the two hinges  56 . The inner loop  52  has two teeth  62  extending from opposite ends of the inner loop. In addition, the outer loop  54  has two teeth  64  extending from each end of the outer loop. As illustrated in  FIG. 5 , the teeth  62 ,  64  are bent to grasp and hold the graft and target vessels together. The anastomosis device  50  of  FIG. 5  is preferably cut from a tube and bent into the shape illustrated in  FIG. 5 . The inner loop  52  is connected to the outer loop  54  at the hinges  56  which are positioned along a bending axis X of the device. Prior to use, the blank  60  including the inner and outer loops  52 ,  54  is bent in a C-shape and the inner and outer loops are pivoted so that the C-shapes face opposite directions.  
         [0040]     As illustrated in  FIG. 7 , the graft vessel  66  is inserted between the inner and outer loops  52 ,  54  and everted over the upper ends of the inner and outer loops such that ends of the graft vessel  66  become caught on the teeth  62 ,  64 . The lower end of the device is arranged substantially in a plane and is inserted through an opening  70  in the target vessel  72  with the teeth  62 ,  64  on the lower end of the device pointing outward. The upper ends of the inner and outer loops  52 ,  54  are then pivoted away from one another to seat the device into the inner wall of the target vessel and secure the graft vessel  66  to the target vessel  72  as illustrated in  FIG. 8 . The pivoting action of the anastomosis device of  FIG. 5  is similar to the pivoting action of scissors being opened and moves the lower ends of the inner and outer loops  52 ,  54  out of the insertion plane. As illustrated in  FIG. 8 , once the graft vessel  66  and target vessel  72  have been connected with the anastomosis device  50 , the edges of the everted graft vessel and the side walls of the target vessel  72  around the opening  70  are both grasped between the inner and outer loops  52 ,  54  of the frame on either side of the opening  70 .  
         [0041]      FIG. 9  illustrates an alternative embodiment of an anastomosis device  80  having two pivoting members or a double scissor arrangement. The anastomosis device  80  includes a frame  82  and first and second pivoting U-shaped members  84 ,  86 . The frame  82  includes side beams  88  having barbs  90  extending downward from an exterior edge of the side beams. The side beams are connected by end beams  92 . Extending from the side beams  92  are four locking tabs  94 . The first and second pivoting U-shaped members  84 ,  86  are connected on either end to a central portion of the end beams  92  by pivot joints  96 . Two lever arms  98  extend from each of the U-shaped members  84 ,  86  adjacent the pivot joints  96 .  
         [0042]     In use, an end of a graft vessel (not shown) is inserted into the center of the frame above the U-shaped members  84 ,  86  and wrapped around or everted over the barbs  90  on the side beams  88 . The U-shaped members  84 ,  86  are arranged in a substantially parallel configuration as shown in  FIG. 9  and are substantially in a plane for insertion into a slit shaped opening  100 . The U-shaped members  84 ,  86  are inserted through the opening  100  or incision in the target vessel  102 . The two lever arms  98  are then each rotated in the direction of the corresponding arrows A in  FIG. 9  to pivot the U-shaped members  84 ,  86  at the pivot joints  96  moving the U-shaped members out of the insertion plane. The opened U-shaped members  84 ,  86  clamp the side wall of the target vessel  102  between the U-shaped members and the side beams  88  of the frame  82 . The lever arms  98  are then folded down and locked in place by folding up the four locking tabs  94  and sliding the lever arms into slots  104  in the tabs.  
         [0043]     The graft vessel has been omitted from  FIGS. 9 and 10  for purposes of clarity. However, it should be understood that the end of the graft vessel as well as the edges of the opening  100  in the target vessel  102  are captured between the frame  82  and the U-shaped pivoting members  84 ,  86 . The square holes  106  in the ends of the frame  82  may be used by an inserting device to grasp the anastomosis device  80 . The edges of the pivoting U-shaped members  84 ,  86  may include serrated edges for incising a target vessel to form the opening  100  in the target vessel.  
         [0044]      FIGS. 11-12  show a variation of the double scissor arrangement for an anastomosis device of  FIG. 9 . The anastomosis device  110  of  FIG. 11  includes a frame  112 , and first and second pivoting U-shaped members  114 ,  116 . The U-shaped members  114 ,  116  are joined to the frame  112  by pivots or living hinges  118 . The pivots  118  are offset vertically from the frame  112  by offset arms  120 . The offset arms  120  preferably have a length which is substantially equal to a thickness of the target vessel wall. Two lever arms  122  extend from each of the first and second U-shaped members  114 ,  116 . The lever arms  122  are rotated in the direction of the arrows A to pivot the U-shaped members  114 ,  116  about the pivots  118  and trap the side walls of the target vessel between the U-shaped members  114 ,  116  and the frame  112 . The lever arms  122  may be provided with rectangular openings  130  which are used by an associated deployment device to manipulate the lever arms  122 .  
         [0045]     According to the embodiment of  FIGS. 11-12 , the frame  112  is provided with a plurality of points  124  on an exterior surface of the frame  112  which hold the everted graft vessel to the frame  112 . Once the graft vessel is punctured by the points  124 , the graft vessel cannot slip off the points  124 . The frame  112  includes locking tabs  126  at either end having recesses  128  for receiving the lever arms  122  in a locked position as illustrated in  FIG. 12 .  
         [0046]      FIGS. 13-14  illustrate an alternative embodiment of an anastomosis device  140  which is longitudinally expandable to cause a lower portion of the device  140  to fold outward trapping the walls of the target vessel with the device  140 . The anastomosis device  140  includes a plurality of linkages  142  which are arranged in two substantially parallel rows. Each of the linkages  142  includes four angled struts  144  which form a substantially diamond shape in the configuration of  FIG. 13  and vertical bendable struts  146  positioned vertically in the center of each of the diamonds formed by the angled struts  144 . Each of the linkages  142  also includes a lower prong  148  arranged substantially vertically for insertion into an opening in the target vessel and an upper prong  150  which is oriented substantially perpendicular to the lower prong  148  in the insertion configuration of  FIG. 13 . The upper and/or lower prongs  148 ,  150  may include barbs  152 . Some of the upper prongs  150  may include loops  154  or other grasping members which can be used by a deployment tool to grasp the anastomosis device  140  during insertion and deployment. Finally, each of the linkages  142  includes one or more stabilizing struts  156 . The stabilizing struts  156  may have a curved configuration to allow longitudinal expansion of the anastomosis device  140 .  
         [0047]     The anastomosis device  140  includes end members  158 ,  160  which connect the ends of the two rows of linkages  142 . The end members  158 ,  160  may take on many different configurations. In the example of the anastomosis device  140  illustrated in  FIGS. 13-14 , the device is formed from a continuous sheet of material. Therefore, the end member  158  is folded to align the first and second rows with one another while the second end member  160  includes a lock member  162  which holds the ends of the rows of linkages together. Each of the end members includes one or more loops  164  or grasping members which are grasped by a deployment tool. The end members  158 ,  160  also preferably include prongs  166  to help grasp the tissue of the everted graft vessel.  
         [0048]     In use, a graft vessel (not shown) is inserted through a center of the anastomosis device  140  and an end of the graft vessel is everted over the lower prongs  148  of the device. The graft vessel may also be everted over the upper prongs  150  and the end member prongs  166 . The prongs  148 ,  150 ,  166  pierce through the graft vessel to securely hold the graft vessel in place in the anastomosis device  140 . Once the graft vessel has been loaded onto the anastomosis device  140 , the lower prongs  148  of the device  140  which are positioned substantially in a plane and the everted end of the graft vessel are inserted through a slit shaped opening in the target vessel. The loops  164  on the end members  158 ,  160  are then used to expand the device in a longitudinal direction with a deployment tool or manually. The longitudinal expansion of the device of  FIG. 13  causes each of the diamond shaped linkages  142  of angled struts  144  to expand longitudinally and causes the bendable vertical struts  146  to bend at their hinges  170 .  
         [0049]     The expanded configuration of the anastomosis device  140  is illustrated in  FIG. 14 . The anastomosis device deployment tool may also expand the device  140  in a direction transverse to the longitudinal axis of the device  140  to enlarge the opening of the target vessel for increased blood flow. Once deployment of the anastomosis device  140  is complete, the wall of the target vessel around the opening in the target vessel is trapped between the upper and lower prongs  148 ,  150 . In the expanded configuration shown in  FIG. 14 , the upper and lower prongs  148 ,  150  are preferably substantially parallel. Alternatively, an angle may be formed between the upper and lower rows of prongs  148 ,  150 .  
         [0050]     The anastomosis device  140  of  FIGS. 13-14  may also be formed as a two piece device or may be split in half at the ends after deployment. The compliance of a split or two piece anastomosis device  140  will allow the device and graft site to flex in response to blood flow.  
         [0051]     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 teeth, barbs, or points which have been discussed above with regard to the various embodiments may be used in varying numbers and arrangements to help secure the vessels in place.  
         [0052]     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. The anastomosis device may be used with natural or synthetic graft vessels.  
         [0053]     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 may be designed to concentrate the bending at a desired location. For example, the pivot joints  96  of the anastomosis device  80  of  FIGS. 9 and 10  may be formed with a thickness or width which is smaller than other portions of the frame and the U-shaped members in order to concentrate the bending in the pivot joints.  
         [0054]     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.