Abstract:
A surgical stapler may include a staple holder, an anvil connected to the staple holder, where at least one of the staple holder and the anvil may be movable relative to the other, and where the anvil may include a groove defined therein, and a cutter that may be slidable along the groove in the anvil. Such a stapler may be used for treating a tissue structure having a lumen defined therein and a wall surrounding the lumen, such as by inserting the anvil into the lumen of the tissue structure through an opening in the wall of the tissue structure; and incising the wall of the tissue structure from the inside, utilizing the cutter.

Description:
[0001]     This application is a continuation of U.S. patent application Ser. No. 10/897,783, filed on Jul. 23, 2004; which in turn is a continuation of U.S. patent application Ser. No. 10/253,347, filed on Sep. 24, 2002, now U.S. Pat. No. 7,063,712; which in turn is a continuation of U.S. patent application Ser. No. 09/842,792, filed on Apr. 27, 2001, now U.S. Pat. No. 6,478,804; which in turn is a divisional of U.S. patent application Ser. No. 09/363,255, filed on Jul. 28, 1999, now U.S. Pat. No. 6,391,038; 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 system, and more particularly, the invention relates to an anastomosis system for controlling a tissue site during an anastomosis procedure.  
         [0004]     2. Brief Description of the Related Art  
         [0005]     Vascular anastomosis is a procedure by which two hollow tissue structures 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 a target vessel such as the coronary artery or the blood supplying artery the surgeon generally has an assistant hold the edges of the incision in the target vessel while the surgeon takes small stitches as close as possible to the edges of the incision. This suturing requires a high degree of precision and is quite time consuming. In addition, during conventional CABG procedures blood flow at the anastomosis site is stopped during suturing. This prevents bleeding from the incision site but also prevents blood from reaching a portion of the heart muscle served by the vessel.  
         [0008]     Accordingly, it would be desirable to provide a vascular anastomosis system which allows the tissue at the anastomosis site to be controlled during suturing or other connection of the graft and target vessels. It would also be desirable to provide a vascular anastomosis system which allows the connection of a graft vessel to a target vessel prior to making an incision in the target vessel which allows blood flow between the target vessel and the graft vessel. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]     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:  
         [0010]      FIG. 1  is a perspective view of an anvil and a plurality of staples according to a first aspect of the present invention;  
         [0011]      FIG. 2  is a perspective view of the anvil of  FIG. 1  being inserted into a target vessel;  
         [0012]      FIG. 3  is a perspective view of the anvil tenting a wall of a target vessel for an anastomosis procedure;  
         [0013]      FIG. 4  is a perspective view of a graft vessel placed adjacent an exterior of the tented target vessel for the anastomosis procedure;  
         [0014]      FIG. 5  is a perspective view of the staples being applied to the graft vessel and the target vessel during an anastomosis procedure;  
         [0015]      FIG. 6  is a perspective view of the completed anastomosis according to the first aspect of the present invention;  
         [0016]      FIG. 7  is a perspective view of a staple supported on a staple holding strip;  
         [0017]      FIG. 8  is a side view of the staple and staple holding strip of  FIG. 7  when the ends of the staple have been bent by contact with an anvil;  
         [0018]      FIG. 9  is a perspective view of an anvil and staple according to another aspect of the present invention;  
         [0019]      FIGS. 10A and 10B  are side views of a plurality of staples supported on two embodiments of expandable staple holding strips;  
         [0020]      FIG. 11  is a perspective view of a portion of an anvil having a movable cutting device;  
         [0021]      FIG. 12  is a side view of an anvil having an external cutting device;  
         [0022]      FIGS. 12A and 12B  are side views of a portion of an anvil and two cutting devices which snap onto the anvil;  
         [0023]      FIG. 13  is a side view of a portion of an anvil with an extendable cutting device;  
         [0024]      FIG. 14  is a side view of the anvil of  FIG. 13  with the cutting device extended;  
         [0025]      FIG. 15  is a side view of a portion of an anvil with an alternative embodiment of an extendable cutting device;  
         [0026]      FIG. 16  is a side view of the anvil of  FIG. 15  with the cutting device extended;  
         [0027]      FIG. 17  is a perspective view of an anvil according to a second aspect of the invention being inserted into a target vessel;  
         [0028]      FIG. 18  is a perspective view of the anvil of  FIG. 17  positioning inside a target vessel and a clamp being advanced to clamp the wall of the target vessel between the anvil and the clamp;  
         [0029]      FIG. 19  is a perspective view of a graft vessel being advanced to the target vessel with a continuous anastomosis staple while the anastomosis site on the target vessel is controlled by the anvil and clamp;  
         [0030]      FIGS. 20-22  are side cross sectional views of the steps of performing the anastomosis with the continuous anastomosis staple shown in  FIG. 19 ;  
         [0031]      FIG. 23  is a perspective view of the completed anastomosis performed as shown in  FIGS. 19-22 ;  
         [0032]      FIGS. 24-27  are perspective views of the steps of an alternative anvil and clamp system for controlling an anastomosis site and forming an incision through the clamped tissue of the target vessel;  
         [0033]      FIG. 28  is a perspective view of a system for controlling a tissue site and performing anastomosis according to the present invention;  
         [0034]      FIG. 29  is a cross sectional view taken along line C-C of  FIG. 28 , showing a first step of the anastomosis procedure;  
         [0035]      FIG. 30  is a cross sectional view taken along line C-C of  FIG. 28 , showing a second step of the anastomosis procedure;  
         [0036]      FIG. 31  is a cross sectional view taken along line C-C of  FIG. 28 , showing a third step of the anastomosis procedure;  
         [0037]      FIG. 32  is a perspective view of an anvil according to another aspect of the present invention for use with sutures; and  
         [0038]      FIG. 33  is a perspective view of the anvil of  FIG. 32  positioned within a target vessel and used to locate a plurality of suture at an anastomosis site. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0039]     The anastomosis system and method according to the present invention uses an anvil to control and support a tissue site during an anastomosis procedure. The anvil is particularly useful for supporting a wall of a coronary artery during attachment of a graft vessel to the coronary artery because the wall of the coronary artery is very thin, difficult to grasp, and susceptible to tearing. Although the present invention is particularly useful for controlling very thin tissues such as the walls of the coronary arteries, the anvil may also be used for controlling other tissue sites.  
         [0040]     As shown in  FIG. 1 , an anvil  10  according to one aspect of the present invention includes a handle  12  and an anvil arm  14  extending substantially perpendicular from the handle. The anvil arm  14  is provided with several staple bending features  16  on opposite sides of the anvil arm  14 . In the anvil shown in  FIG. 1 , the staple bending features  16  each include a plurality of recesses  20  which receive the ends of staples and cause the staple ends to bend over.  
         [0041]     Also shown in  FIG. 1  are a plurality of staples  22  connected to a staple holding strip  24 . The staples  22  are preferably U-shaped staples which are arranged in a spaced apart parallel configuration such that the staples all lie in a single plane.  
         [0042]     The anvil arm  14  has a sharp distal end  28  for puncturing the tissue of a target vessel to insert the anvil arm  14  into the target vessel. As illustrated in  FIG. 2 , the anvil arm  14  is inserted into a pressurized or unpressurized target vessel  30  by puncturing the target vessel with the distal end  28  of the anvil arm. The hole which is formed in the wall of the target vessel  30  by the anvil arm  14  is small enough to prevent significant bleeding through the puncture site. The hole is preferably less than 2 mm, and more preferably less than 1 mm in width.  
         [0043]     Once the anvil arm  14  has been inserted into the target vessel  30 , the anvil arm  14  is pulled against an inner wall of the target vessel causing tenting of the thin tissue of the vessel wall as illustrated in  FIG. 3 . This tenting of the vessel wall provides control over the anastomosis site during an anastomosis procedure which is described with respect to  FIGS. 4-6 .  
         [0044]     As shown in  FIG. 4 , a graft vessel  32  is advanced to the anastomosis site and an end  34  of the graft vessel is positioned adjacent and exterior of the target vessel  30  at the anastomosis site. The tented portion of the target vessel  30  is inside the graft vessel in the step of  FIG. 4 . As shown in  FIG. 5 , a staple holder  38  is provided having two arms  40  which are pivotally connected to the handle  12  of the anvil. Alternatively, the pivoting arms  40  of the staple holder may be connected to a separate device. A staple holder  38  may be used to hold individual staples or preferably, the staple holder will hold the staple holding strips  24  as shown in  FIG. 1 . The staples  22  are inserted through the tissue of the graft vessel  32  and the target vessel  30  by pivoting the arms  40  of the staple holder  38  towards the anvil arm  14 . When the ends of the staples  22  engage the staple bending features  16  on the anvil arm  14 , the ends of the staples are bent over securing the graft vessel  32  and target vessel  30  together. Once the staple ends are bent over, the staples  22  are released from the staple holding strip  24  or the staple holder  38  resulting in spaced apart staples securing the graft vessel  32  and the target vessel  30  together as shown in  FIG. 6 .  
         [0045]     After stapling is complete, an incision is formed in the wall of the target vessel  30  to allow blood flow between the target vessel and the graft vessel  32 . Some Samples of methods and devices for forming the incision will be described in further detail below. After completion of the anastomosis, the anvil arm  14  is withdrawn from the target vessel  30  between adjacent staples  22 . The withdrawal of the anvil arm  14  leaves a gap which is approximately the same as the spacing between adjacent staples. Accordingly, no blood leakage occurs at the location where the anvil arm has been withdrawn.  
         [0046]      FIG. 6  illustrates a completed anastomosis between a target vessel  30  and a graft vessel  32  with a plurality of staples  22 . A spacing between the staples  22  is preferably approximately 1 to 4 mm. This spacing is similar to the spacing between sutures in a conventional sutured anastomosis.  
         [0047]     One example of an anvil arm  14  according to the present invention has a height and a width of about 2 mm or less, preferably about 1 mm or less, and a length of about 2 to 15 mm, preferably 5 to 12 mm. The length of the anvil will vary depending on the diameter of the graft vessel selected. Preferably, a length to width ratio of the anvil arm  14  is between 2:1 and 15:1.  
         [0048]     The preferred staples  22  for use in the present invention have widths of about 0.2-3 mm, preferably about 2 mm or less and leg lengths of about 0.2-3 mm.  
         [0049]      FIGS. 7 and 8  illustrate one example of a staple  22  connected to a staple holding strip  24 . This staple  22  includes barbed staple ends  52  extending from the front portion  55  of the staple and a C-shaped portion  54  extending from a rear of the staple for connecting the staple to the staple holding strip  24 . The staple holding strip  24  includes a plurality of protrusions  56  for receiving the staples  22 . The C-shaped portion  54  of the staple is received around one of the protrusions  56  and is preferably secured in place at one or more locations such as by welds  58  or other frangible portions. As shown in  FIG. 8 , when the staple holding strip  24  is advanced toward the anvil arm  14 , the barbed staple ends  52  are received in the recesses  20  in the anvil arm causing the barbed staple ends to bend towards one another. At the same time that the barbed staple ends  52  bend over, or after the bending of the staple ends, the staple is detached from the staple holding strip  24 . The staple  22  may be detached from the staple holding strip  24  by the action of bending the barbed staple ends, by bending a frangible connection between the staple holding strip and the staples to separate the staples, or any other known separation methods, such as melting of a connection between the staple and the staple holding strip.  
         [0050]      FIG. 9  illustrates an alternative embodiment of a staple  22   a  having inwardly curved barbed staple ends  52   a.  These inwardly curved barbed staple ends do not require the curved staple bending surfaces of the recesses  20  to bend the ends of the staples over. As shown in  FIG. 9 , the staple bending features  16   a  on the anvil arm  14   a  may be formed as a longitudinal groove along the anvil arm. When the curved ends  52   a  of the staple  22   a  are received in the groove  16   a  of the anvil arm  14   a,  the ends bend inward to secure the tissue with the staple.  
         [0051]      FIG. 10A  illustrates a plurality of staples  22   a  positioned on an expandable staple holding strip called an expandable backbone  66 . The expandable backbone  66  includes a plurality of elements  68  which are interconnected by one or more expanding members  70 . Each of the backbone elements  68  is provided with a connecting diamond member  72  which is connected to one of the staples  22   a.  According to the embodiment illustrated in  FIG. 10A , the staples  22   a  are each connected to the diamond members  72  by a thin connecting section  74 . The expandable backbone  66  allows the spacing between the staples  22   a  to be adjusted for the particular anastomosis to be performed. Preferably the backbone  66  allows expansion of the distance between staples from a distance of approximately 0.1 mm to a distance of approximately 1 to 4 mm, i.e., expansion of up to 40 times the original spacing.  
         [0052]     The expanding backbone  66  also includes two openings  76  at opposite ends which may be engaged by pins on an anastomosis system or staple holder. The opening  76  allow the backbone to be easily expanded by relative motion of holding pins.  
         [0053]     The connecting diamond members  72  are configured to collapse inwardly toward the backbone when the staples  22   a  engage the staple bending surfaces  16   a  of the anvil. The collapsing of the diamond members  72  forces the staples  22   a  to separate from the diamond members at the connecting sections  74 .  
         [0054]      FIG. 10B  illustrates an alternative embodiment of staples  22   a  and a backbone  66 . In the embodiment of  FIG. 10B , the staples  22   a  are each connected to the associated backbone elements  68  at two connecting sections  74 .  
         [0055]      FIG. 11  shows a portion of an anvil arm  14  with a movable cutting device  44 . The cutting device  44  includes a base  46  and a blade  48 . The base  46  of the cutting device  44  is positioned in a longitudinal groove  50  in the anvil arm  14 . After the anvil arm  14  has been inserted into the target vessel, the cutting device  44  may be moved longitudinally along the anvil arm to form an incision in the target vessel.  
         [0056]      FIGS. 12, 12A , and  12 B illustrate external cutting devices which are advanced down onto the anvil  14  after the anastomosis procedure and cut an incision in the target vessel from an exterior of the target vessel as the anvil is withdrawn. As shown in  FIG. 12 , a knife  62  is positioned on a knife arm  64  which is movable along the handle  12  of the anvil. The knife  62  is moved downward until the knife engages a recess  65  in the anvil  14 . As the anvil  14  is withdrawn from the anastomosis site, the knife  62  forms the incision in the target vessel.  
         [0057]      FIGS. 12A and 12B  illustrate two alternative embodiments of the knife  62  which snap onto a corresponding engagement surface  65  of the anvil  14  so that the knife and anvil are secured together for formation of the incision during removal of the anvil from the anastomosis site.  
         [0058]      FIGS. 13-16  illustrate two variations of extendable cutting devices for making an incision in the target vessel while drawing the anvil arm  14  from the target vessel.  FIG. 13  illustrates an anvil arm  14   b  having a blade  78  connected to a blade support  80 . When the blade support  80  is pulled in the direction of the arrow A with respect to the anvil arm  14   b,  the blade  78  moves from a forwardly extending position shown in  FIG. 13  to an upwardly extending position shown in  FIG. 14 . The blade  78  in the forwardly extending position may be used to form the small opening to insert the anvil arm  14  into the target vessel. After an anastomosis has been performed, the blade  78  is moved to an upwardly angled or a vertical position in which the blade is used to form an incision in the target vessel as the anvil arm  14   b  is removed from the target vessel.  
         [0059]      FIGS. 15 and 16  illustrate an alternative embodiment of an anvil arm  14   c  having a blade  84  and a blade support  86 . While the anvil arm  14   c  is being inserted into the target vessel and during the anastomosis procedure, the blade  84  is positioned in a recess  88  in the anvil arm. The blade  84  may be moved from the position of  FIG. 15  to the extended position of  FIG. 16  by moving the blade support  86  in the direction of the arrow B with respect to the anvil arm. Alternatively, the blade  84  may be extended automatically upon withdrawal of the anvil arm  14  when a blade tip  90  catches on an interior surface of the target vessel wall during withdrawal of the anvil arm.  
         [0060]     The examples of extendable cutting devices for use with the anvil according to the present invention which are shown in  FIGS. 13-16 , are merely shown as examples of the type of cutting devices which may be used for making the incision. Once these cutting devices or blades have been extended from the anvil arm, they may be fixed to perform cutting as the anvil arm is removed from the target vessel or the blades may be movable along the anvil arm to make an incision prior to removal of the anvil arm from the target vessel.  
         [0061]      FIGS. 17-23  illustrate an alternative embodiment of an anvil  100  which is used with a clamp  102  for controlling an incision site during an anastomosis procedure. As shown in  FIGS. 17 and 18 , the anvil  100  includes an anvil arm  104  and a handle  106 . The clamp  102  is slidable on the handle  106  to clamp the tissue of the target vessel  30  between the clamp  102  and the anvil arm  104 . As in the embodiments discussed previously, the anvil arm  104  includes two rows of staple bending features  108  in the form of recesses positioned in two parallel rows along a top surface of the anvil. The clamp  102  has a central opening  1   10 . Once the tissue of the target vessel wall has been trapped between the clamp  102  and the anvil arm  104 , an incision may be made through the target vessel wall and the edges of the incision are controlled by the combination of the anvil and the clamp.  
         [0062]     As shown in  FIG. 19 , a continuous anastomosis staple device  114  may be used to connect the graft vessel  32  to the target vessel  30  at the anastomosis site. The staple device  114  as shown in  FIG. 19  includes a plurality of linkages forming a tubular configuration and a plurality of staple ends extending from the linkages.  FIGS. 20-22  illustrate how the staple ends  116  of the staple device  114  are positioned in the end of the graft vessel  32  and are inserted through the incision  118  in the target vessel and bent over by contact with the staple bending features  108  of the anvil. As shown in  FIG. 22 , the opposite ends  120  of the staple device  114  are folded over to complete the anastomosis.  FIG. 23  illustrates a completed anastomosis performed according to the steps illustrated in  FIGS. 19-22 .  
         [0063]      FIGS. 24-27  illustrate an alternative embodiment of an anvil  14   d  having a cutting wire  124  for forming the incision in the wall of the target vessel  30 . The cutting wire  124  of  FIGS. 24-27  may be used to form an incision either before or after performing an anastomosis procedure. For forming the incision after the anastomosis procedure, a clamp  126  is used to trap the tissue at the anastomosis site between the clamp and the anvil prior to performing the incision as shown in  FIGS. 26 and 27 .  
         [0064]      FIG. 28  shows a system  140  for controlling a tissue site and performing anastomosis according to the present invention. For purposes of clarity, the staple holder and staples have been omitted from  FIG. 28 . The system  140  includes an anvil  142 , a cutter  144 , and a graft vessel holder  146  all mounted on a handle  148 . The anvil  142  is mounted on the handle  148  and connected to an actuator  150  which allows the anvil to be moved downward against the bias of a spring inside the handle. The cutter  144  may be spring biased or fixed and is positioned on the handle  148  directly above the anvil  142 . The graft vessel holder  146  includes two fixed arms  152  and two movable arms  154 . The two movable arms  154  are connected to a second actuator  156  on the handle  148 . Depression of the second actuator  156  against the bias of a spring within the handle causes the movable arms  154  to be moved downward away from the fixed arms to receive portions of a graft vessel between the movable and fixed arms.  
         [0065]     The operation of the system  140  of  FIG. 28  is shown in the cross sectional views of  FIGS. 29-31 . As shown in  FIG. 29 , an end of a graft vessel  32  is split so that the two halves of the graft vessel can be held by the graft vessel holder  146 . In order to load the graft vessel into the system  140 , the first actuator  150  and the second actuator  156  are depressed to move the anvil  142  and the movable arms  154  downward. The split graft vessel  32  is then inserted between the fixed and movable arms  152 ,  154  and the second actuator  156  is released to trap the ends of the graft vessel, as shown in  FIG. 30 . The anvil  142  is then inserted into the target vessel  30  as described above with respect to the various other anvil embodiments.  
         [0066]     Once the anvil has been inserted in the target vessel  30  as shown in  FIG. 30 , the actuator  150  is released to allow the anvil to move upward to tent the wall of the target vessel.  FIG. 31  illustrates the tented target vessel  30  positioned adjacent the split and trapped graft vessel  32  in a position for performing anastomosis. The staple holders  38  are then advanced in the direction of the arrows D toward opposite sides of the anvil to staple the graft vessel and target vessel together. Preferably, the staple holders hold a staple strip with an expandable backbone as shown in  FIGS. 10A and 10B . The holders  38  may be provided with movable pins which allow a spacing between the staples to be adjusted depending on a size of the graft vessel used. Once the staples have been placed the anvil  142  is removed and the cutter  144  makes an incision in the target vessel during removal of the anvil.  
         [0067]      FIGS. 32 and 33  illustrate the use of an anvil  130  for controlling the tissue at an anastomosis site. The anvil  130  includes a longitudinal slot  132  extending through the anvil for application of a plurality of conventional sutures at the anastomosis site. According to this method, the anvil  130  is inserted into the target vessel  30  and pulled against the interior wall of the target vessel, tenting the target vessel as shown in  FIG. 33 . Sutures  134  are then passed through the slot  132  in the anvil  130  and through the tissue of the target vessel wall on opposite sides of the anvil. Once the sutures are placed as shown in  FIG. 33 , an incision is made in the target vessel along a center of the anvil  130 . A center portion of each of the sutures  34  is then pulled out through the incision in the target vessel and cut so that an even row of sutures is provided along each of the sides of the incision. This system eliminates the tedious procedure of placing each individual suture very close to the edge of the incision in the very thin and flexible target vessel wall. Each of the sutures  134  are connected to a graft vessel in a conventional manner completing the anastomosis. The anvil as shown in  FIGS. 32 and 33  allows quick and easy placement of a plurality of sutures in a very even manner close to the edge of the incision. For example, the sutures of a conventional anastomosis are generally within about one millimeter of the edge of the incision and are preferably within  0 . 5  millimeters of the edge of the incision.  
         [0068]     The invention has been described as including staple bending features provided on the anvil and staples provided at an exterior of the tissue. According to an alternative embodiment of the invention, the staples and/or staple holding strips may be positioned on the anvil and an exterior member with staple bending features may be moved toward the anvil to bend the ends of the staples and secure the graft and target vessels together.  
         [0069]     While the invention has been described in detail, 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. It is to be understood that the invention is not limited to the details of construction, the arrangements of components, and/or the method set forth in the above description or illustrated in the drawings. Statements in the abstract of this document, and the figures, are merely exemplary and not limiting; they are not, and cannot be interpreted as, limiting the scope of the claims. Topical headings and subheadings are for the convenience of the reader only. They should not and cannot be construed to have any substantive significance, meaning or interpretation, and should not and cannot be deemed to indicate that all of the information relating to any particular topic is to be found under or limited to any particular heading or subheading. Therefore, the invention is not to be restricted or limited except in accordance with the following claims and their legal equivalents.