Patent Publication Number: US-2010114120-A1

Title: Assemblies for deploying fasteners in tissue and snares for use in such assemblies

Description:
FIELD OF THE INVENTION 
     The present invention generally relates to assemblies for deploying fasteners in tissue. The present invention more particularly relates to such assemblies for deploying tissue fixation devices wherein the assemblies include at least one snare for stabilizing the tissue during fastener deployment. 
     BACKGROUND 
     Tissue fixation devices or fasteners find many different uses in the medical field. For example, in surgery, multiple tissue layers are often fixed together to maintain the tissue in a desired shape or configuration, or to effect a desired seal with the tissue. Unfortunately, tissue fixation is not easily accomplished in the human body. This results because the tissue to be fastened often does not lend itself to stabilization. The tissue can be too slippery or lack structural integrity or texture to obtain a good hold on the tissue to enable fastener placement where desired or required. Tissue stabilization is thus important in tissue fixation to assure that after fastener deployment, the tissue does indeed have the desired shape or provides the desired seal. 
     Fastener deployment is also complicated by limited space in which to localize the tissue or accommodate fastener deployment tools. For example, tissue stabilization for fastening is particularly difficult when the fastening devices must be passed through a patient&#39;s mouth and down the esophagus. Further, visualization of the fastener deployment site can also be limited by both lack of light and interfering tissue. 
     Hence, there is a need in the art for improved tissue fastener deployment assemblies. More particularly, there is a need in the art for such assemblies, which may be readily placed in the body, and which afford improved tissue stabilization notwithstanding varying tissue structures, textures, and accessibilities. 
     SUMMARY 
     The invention provides an assembly for deploying a fastener through tissue. The assembly comprises a fastener deploying device arranged to deploy a fastener through tissue and a snare arranged to bind the tissue and fastener deploying device together as the fastener deploying device deploys a fastener through the tissue. 
     The snare may include a cable loop arranged to encircle the tissue and fastener deploying device to bind the tissue and fastener deploying device together. The snare may further include an elongated member having a proximal end, a distal end, and at least one longitudinal lumen extending between the proximal end and the distal end, and the cable loop may extend from the distal end of the elongated member through the at least one longitudinal lumen. 
     The elongated member may be retroflexed at the distal end. The fastener deploying device may include a passageway and the elongated member may extend through the passageway. The elongated member may be an endoscope. 
     The assembly may further comprise a mechanical retractor that pulls the tissue through the snare. The mechanical retractor may include a helical coil that grabs the tissue. 
     The snare may include a cable formed in a loop including first and second ends and a spreader that increases the spacing between the ends of the loop. The snare spreader may comprise a spreader block having a pair of lumens. The lumens may terminate in respective spaced apart openings defining the spacing between the cable loop ends. The spreader block may include a tissue engaging surface between the spaced apart openings against which the tissue layers lie. The snare may further comprise an opposing block carried on the cable having an opposing tissue engaging surface so that the tissue engaging surface and the opposing tissue engaging surface may confine the tissue there between. The spreader block and the opposing block may each be hollowed out. The opposing block may be hollowed out to provide, for example, clearance for a deployed fastener to pass through the tissue. 
     The snare may include a plurality of cable loops arranged to encircle the tissue and fastener deploying device to bind the tissue and fastener deploying device together. The plurality of cable loops may be arranged in side-by-side relation. The plurality of cable loops may be a pair of cable loops arranged in side-by-side relation. The fastener deploying device may then be arranged to deploy a fastener between the pair of cable loops. 
     In another embodiment, the invention provides an assembly for deploying a fastener through tissue, comprising a snare including an elongated member having a proximal end, a distal end, and at least one longitudinal lumen extending between the proximal end and the distal end, and a cable loop extending from the distal end of the elongated member through the at least one longitudinal lumen. The assembly further comprises a fastener deploying device arranged to deploy a fastener. The cable loop of the snare is arranged to encircle the tissue and fastener deploying device and bind the tissue and fastener deploying device together as the fastener deploying device deploys a fastener through the tissue. 
     In another embodiment, the invention provides a method of deploying a fastener through tissue. The method comprises the steps of providing a fastener deploying device arranged to deploy a fastener through tissue, providing a snare arranged to bind the tissue and fastener deploying device together as the fastener deploying device deploys a fastener through the tissue, binding the tissue and the fastener deploying device together with the snare, and deploying a fastener through the tissue with the fastener deploying device. 
     The snare may include a cable loop and the binding step may include the step of encircling the tissue and fastener deploying device with the cable loop to bind the tissue and fastener deploying device together. The snare may further includes an elongated member having a proximal end, a distal end, and at least one longitudinal lumen extending between the proximal end and the distal end with the cable loop extending from the distal end of the elongated member through the at least one longitudinal lumen, and the binding step may further include retroflexing the distal end of the elongated member. The fastener deploying device may include a passageway and the method may further comprise the step of feeding the elongated member down and through the passageway. The elongated member may be an endoscope and the method may further comprise the step of viewing the tissue and fastener deploying device through the endoscope with the distal end of the endoscope retroflexed. 
     The method may further comprise the step of pulling the tissue through the snare. The pulling step may include grabbing the tissue with a helical coil. 
     The snare may include a cable formed in a loop including first and second ends and the method may further comprise the step of spreading the ends of the loop. The deploying step may then include directing a fastener through the tissue between the spread ends of the cable loop. The snare may include a pair of cable loops and the deploying step may include driving the fastener through the tissue between the pair of cable loops. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The invention, together with further objects and advantages thereof, may best be understood by making reference to the following description taken in conjunction with the accompanying drawings, in the several figures of which like reference numerals identify like elements, and wherein: 
         FIG. 1  is a perspective side view with portions cut away of a stomach and a fastener deployment assembly including a fastener deployment device and a snare according to a first embodiment of the invention in use to deploy at least one fastener to maintain a gastroesophageal valve (GEV) therein; 
         FIG. 2  is a perspective side view with portions cut away of the stomach and the fastener deployment assembly of  FIG. 1  during an initial stage of its use; 
         FIG. 3  is a perspective side view with portions cut away of the stomach and the fastener deployment assembly of  FIG. 1  during a further stage of its use to deploy a fastener; 
         FIG. 4  is a perspective side view with portions cut away of the stomach and the fastener deployment assembly of  FIG. 1  as the snare captures the fastener deployment device during a further stage of its use to deploy a fastener; 
         FIG. 5  is a perspective side view with portions cut away of the stomach and the fastener deployment assembly of  FIG. 1  during a further stage of its use and as a fastener is being delivered for deployment; 
         FIG. 6  is a perspective side view with portions cut away of the stomach and the fastener deployment assembly of  FIG. 1  showing the fastener deployment device being captured during an initial stage of an alternative method of capture; 
         FIG. 7  is a perspective side view with portions cut away of the stomach and the fastener deployment assembly of  FIG. 1  showing the fastener deployment device being captured according to the alternative method of capture; 
         FIG. 8  is a side plan view of a fastener deployment assembly according to a further embodiment of the invention; 
         FIG. 9  is a perspective side view with portions cut away of a stomach and the fastener deployment assembly of  FIG. 8  during an initial stage of its use; 
         FIG. 10  is a perspective side view with portions cut away of the fastener deployment assembly of  FIG. 8  during a further stage of its use and as a fastener is being deployed; 
         FIG. 11  is a perspective side view with portions cut away of the fastener deployment assembly of  FIG. 8  after the fastener has been deployed; 
         FIG. 12  is a perspective side view with portions cut away of a further fastener deployment assembly according to another embodiment of the invention; 
         FIG. 13  is a perspective side view, with portions cut away, of still another fastener deployment assembly embodying the invention; and 
         FIG. 14  is a perspective side view showing how the fastener deployment assembly may be employed to deploy a fastener. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  is a perspective side view with portions cut away of a stomach  10  and a fastener deployment assembly  30  embodying the present invention. The assembly generally includes a fastener deployment device  30  and a snare  20  shown in use to deploy at least one fastener for maintaining a gastroesophageal valve  12 . 
     The fastener deployment device  30  includes an elongated body  32 . The body  32  has a distal end  34  extending into the stomach  10 . The body includes a through channel  36  that sliding receives the snare  20 . The body further has a fastener-directing channel  38  that directs a fastener  50  into the stomach tissue to be fastened. 
     The snare  20  includes an elongated member  22 , a catheter  24 , and a cable  40  that forms a cable loop  26 . The elongated member is preferably an endoscope having a distal end  23 , a proximal end (not shown) and a lumen  25  that receives the catheter  24 . The endoscope  22  may thus be used for both introducing the snare into the stomach and providing visualization of the fastener deployment process. 
     The fastener  50  may take the form of the fasteners and be deployed as shown and described, for example, in co-pending application Ser. No. 11/043,903, filed Jan. 25, 2005, for SLITTED TISSUE FIXATION DEVICES AND ASSEMBLIES FOR DEPLOYING THE SAME, which application is incorporated herein in its entirety. To that end, the fastener  50  is carried on a deployment wire or stylet  52  and the leading member thereof is pushed by a pusher  54  into and through the tissue. In accordance with aspects of the invention, during the fastener deployment process, and as illustrated in  FIG. 1 , the fastener deployment device  30  and the tissue of valve  12  are bound together by the snare  20 . This provides stabilization of the tissue to permit the fastener  50  to be accurately placed and forced through the tissue.  FIGS. 2-5  illustrate a manner in which the fastener deployment of  FIG. 1  may be achieved. 
     In  FIG. 2  it may be seen that the endoscope  22  has been passed down the elongated member  32  and retroflexed to provide visualization of the process. Thereafter, the catheter  24  is pushed out of the distal end of the endoscope  22 . The cable loop  26  is then pushed out of the distal end of the catheter  24 . 
     The catheter  24  preferably has shape-memory so that as the catheter  24  is advanced further distally, it will assume the shape illustrated in  FIG. 3 . More specifically, as the catheter  24  is played out, it curls around to cause the cable loop  26  to be loosely received over the endoscope  22 . 
     Referring now to  FIG. 4 , with the cable loop  26  loosely received on the endoscope  22 , the whole assembly may now be translated in an oral or proximal direction. The assembly is translated enough to position the cable loop  26  around both the fastener deployment device  30  and the tissue  12 . The assembly is now ready to bind the fastener deployment device  30  and the tissue  12  together. 
     As will be noted in  FIG. 5 , the cable loop is now pulled tight to bind the fastener deployment device  30  to the tissue  12 . A fastener  50  may now be pushed down the stylet  52  by the pusher  54  within the channel  38  to the tissue as shown in  FIG. 1  for deployment. 
       FIGS. 6 and 7  show another way in which the cable loop  26  may be manipulated to loosely receive the fastener deployment device  30  and the tissue  12 . Once again the endoscope  22  is retroflexed to permit visualization. Instead of plying out the catheter  24 , the proximal ends  27  of the cable loop  26  are twisted around as indicated by the arrows  28 . This will cause the loop  26 , which is preferably preformed in a bent structure, to swing around as shown in  FIG. 7  from the dashed line position to the solid line position. The cable loop  26  is now loosely received over the fastener deployment device  30  and the tissue  12 . The assembly is now ready to deploy a fastener as shown in  FIGS. 1 and 5 . 
     Referring now to  FIG. 8 , it shows another embodiment of the present invention. The assembly  100  of  FIG. 8  generally includes a snare  120  and a fastener deployment device  130 . 
     The snare  120  includes an elongated conduit  122  that guides two legs of a cable  140  that form a loop  126 . The snare also includes a spreader block  160 . The spreader block  160  has diverging lumens  162  and  164  that terminate at a spreader surface  165 . The diverging lumens  162  and  164  increase the spacing between the ends  142  and  144  of the cable loop  126 . 
     The fastener deployment device  130  includes a conduit  132  that extends down the conduit  122 . The conduit  132  terminates with an enlarged section  133  at the spreader surface  165 . 
     As will be seen subsequently, tissue to be fastened is pulled through the cable loop  126 . The tissue engaging the spreader surface  165  is caused to spread to form tissue layers  170  and  172 . The cable  140  may then be drawn tight causing the cable loop  126  to securely hold the tissue layers against the spreader surface  165 . Now, the stylet  152  may be guided by the conduit  132  into and through the tissue layers  170  and  172 . The fastener  150  is then pushed down the stylet  152  by the pusher  154  into the tissue layers  170  and  172 . The enlarged portion  133  of the conduit  132  is provided to accommodate the fastener  150  and to provide space for its deployment. 
     Referring now to  FIGS. 9 through 11 , they show a manner in which the assembly  100  of  FIG. 8  may be employed to fasten tissue layers of a stomach  10 . In  FIG. 9 , it will be noted that the conduit  122  has been fed into the stomach  10 . The assembly  100  also includes a mechanical retractor  180  comprising another conduit or catheter  188 , a first cable  182 , and a second cable  186 . The first cable  182  extends through the cable loop  126  and terminates in a tissue grabber, such as a helical coil  184  that, when engaged with and rotated against tissue, grabs the tissue. Accordingly, as seen in  FIG. 9 , the helical coil  184  has been rotated against the tissue of the stomach  10  and has grabbed the tissue. As may be appreciated, other forms of tissue grabbers may be employed in place of the helical coil  184 . The second cable  186  extends down the conduit  122 . It serves to provide guiding assistance to the first cable  182  when the helical coil is directed to the tissue. 
     The cable  182  is now used to pull the tissue through the cable loop  126 . As may be seen in  FIG. 10 , the tissue is pulled through the cable loop  126  and along side the spreader block and the conduit  122 . The spreader surface  165  forms a snare base that exerts a force against the tissue. Here, that force is in the direction of travel by the fastener  150 . The tissue is pulled by the cable  182  at an angle and in a direction having a component opposed to the direction of the force applied to the tissue by the snare base. In the process, the tissue layers  170  and  172  are formed against the spreader surface  165 . The cable loop  126  may now be drawn tight and the fastener  150  may be deployed as previously described. 
       FIG. 11  shows the fastener  150  deployed through the tissue layers  170  and  172 . The cable loop  126  has been loosened to permit the fastened tissue to be removed from the snare after the helical coil  184  is counter-rotated out of the tissue. 
       FIG. 12  shows another embodiment of the invention. The assembly  110  there shown is substantially similar to the assembly  100  except for the fact that the snare  112  of the assembly  110  includes an opposing block  190  that opposes spreader block  160  and that the assembly  110  employs an alternate form of mechanical tissue retractor  192 . Firstly, with respect to the mechanical retractor  192 , it will be seen that it includes a tissue forceps  194  instead of a helical coil for grabbing the tissue. With respect to the opposing block  190 , it provides an opposing surface  195  juxtaposed to the surface  165  of the spreader block  160  to confine the tissue to be fastened there between. The opposing block  190  has a hollowed out portion  196  that receives the tip  153  of the stylet  152  to protect surrounding tissue from the tip  153  and to provide space for the fastener  150 . In use, the operation of the assembly  110  is substantially the same as that described with respect to the assembly  100  of  FIGS. 9 through 11 . 
     Referring now to  FIGS. 13 and 14 , they illustrate another assembly  200  embodying the invention. Here, the assembly includes a snare  220  comprising a pair of cable loops  226  and  326  formed from cables  240  and  340  respectively. The legs of the cables  240  and  340  extend down a conduit  222  includes a channel  238  to accommodate the fastener deployments stylet  252  and pusher  254  to enable deployment of fastener  250 . The channel extends down the conduit  222  to place the fastener in between the cables loops  226  and  326 . 
       FIG. 13  schematically shows the assembly  200  in use. Here it may be seen that a mechanical retractor  280  includes a cable  282  and helical coil  284 . They have been employed to pull the tissue layers  270  and  272  through both cable loops  226  and  326 . The two spaced cable loops  226  and  326  function together to prevent the tissue form slipping out of the grip of the snare  220 . The snare  220  thus holds the tissue against the channel to permit a fastener to be deployed by the stylet  252  and pusher  254  as previously described. 
     While the invention has been described by means of specific embodiments and applications thereof, it is understood that numerous modifications and variations may be made thereto by those skilled in the art without departing from the spirit and scope of the invention. It is therefore to be understood that within the scope of the claims, the invention may be practiced otherwise than as specifically described herein.