Curved implantable sheath and method of making same

Abstract

The present invention provides a method for making a curved implantable sheath. A sheet of flexible material is urged into engagement with a member having a curved surface having a desired configuration. The sheet and member are placed in a fixation solution so that the sheet assumes the configuration of the surface engaged thereby.

What is claimed is:  
     
         1 . A method for making a sheath having a curved contour, comprising: 
 providing a sheet of a biological tissue material, the sheet having ends spaced apart from each other by elongated side edges;    mounting the sheet to an elongated member having a curved exterior portion such that at least a substantial portion of the sheet engages the exterior portion;    placing the sheet and elongated member in a fixation solution so that at least part of the sheet is fixed to a configuration defined by the exterior portion of the elongated member engaged thereby; and    separating the sheet from the elongated member to provide an elongated sheath of substantially biocompatible material having a curved contour corresponding to the curved exterior portion of the elongated member.    
     
     
         2 . The method of  claim 1 , prior to placing the sheet and elongated member in a fixation solution, the method further comprising: 
 forming a generally tubular apparatus with the sheet of the biological tissue material; and    urging the elongated member into the tubular apparatus.    
     
     
         3 . The method of  claim 2 , the elongated member having a generally cylindrical sidewall portion that extends arcuately between opposite ends thereof.  
     
     
         4 . The method of  claim 2 , the sidewall portion of the elongated member having a radius of curvature extending between the opposite ends thereof that is greater than about forty-five degrees.  
     
     
         5 . The method of  claim 3 , the elongated member having an outer diameter that approximates the diameter of the tubular apparatus.  
     
     
         6 . The method of  claim 2 , the forming further comprising securing the side edges of the sheet of biological material relative to each other, such that when the elongated member is urged into the tubular apparatus, the relative spacing between the side edges of the sheet of biological material remains substantially unchanged.  
     
     
         7 . The method of  claim 6 , further comprising removing a strip of tissue adjacent and coextensive at least one of the side edges to form an elongated sheath having a curved contour that extends arcuately between opposite ends thereof and having generally C-shaped cross section.  
     
     
         8 . An elongated sheath produced according to  claim 7 , the elongated sheath having a curved contour extending arcuately between opposite ends thereof and having generally C-shaped cross section.  
     
     
         9 . The method of  claim 5 , the securing of the side edges further comprising suturing the side edges relative to each other to define a suture line that extends between the ends of the tubular apparatus.  
     
     
         10 . The method of  claim 8 , further comprising removing the suture line to define an elongated sheath having a curved contour that extends arcuately between opposite ends thereof and having generally C-shaped cross section.  
     
     
         11 . The method of  claim 1 , wherein the biological tissue material comprises animal pericardium.  
     
     
         12 . An elongated sheath produced according to  claim 1 .  
     
     
         13 . A method of making an implantable sheath having a curved contour, comprising: 
 providing a sheet of tissue, the sheet having ends spaced apart from each other by elongated side edges;    placing the sheet into engagement with a surface of an elongated member, the surface being curved about a long axis that extends between ends of the elongated member;    urging the side edges of the sheet toward each other so as to cover at least part of the curved surface of the elongated member;    fixing the sheet in a fixation solution so that at least part of the sheet assumes a contour defined by the at least part of the curved surface of the elongated member engaged by the sheet; and    separating the sheet relative to the elongated member to provide an elongated sheath of substantially biocompatible material having a curved contour corresponding to the at least part of the curved surface of the elongated member.    
     
     
         14 . The method of  claim 13 , the urging further comprising applying retaining elements to hold the sheet relative to the elongated member such that at least a substantial portion of the sheet engages the at least part of the curved surface of the elongated member.  
     
     
         15 . The method of  claim 14 , the retaining elements including sutures that connect the opposed side edges of the sheet.  
     
     
         16 . The method of  claim 15 , the sutures being applied to connect the side edges prior to placing the sheet into engagement with the elongated member.  
     
     
         17 . The method of  claim 14  further comprising removing the retaining elements after fixation to provide a curved sheath having a generally C-shaped cross section.  
     
     
         18 . The method of  claim 14 , the elongated member extending arcuately between spaced apart ends of the elongated member according to a radius of curvature, such that after fixation the curved sheath extends arcuately between the ends of the sheet according to radius of curvature.  
     
     
         19 . The method of  claim 14 , further comprising removing the retaining elements together with a strip of tissue from the sheet located adjacent and coextensive to at least one of the side edges of the sheet to form an elongated sheath having a curved contour that extends arcuately between opposite ends thereof and having generally C-shaped cross section.  
     
     
         20 . A curved implantable sheath comprising: 
 an elongated sheet of biological tissue material having first and second ends spaced apart from each other by opposed side edges;    the elongated sheet extending arcuately between the first and second ends according to a radius of curvature; and    the side edges of the elongated sheet being urged toward each other about a central axis that extends arcuately between the first and ends according to the radius of curvature to define a generally C-shaped cross section of the curved sheath, the curved sheath having undergone a fixation process to maintain such configuration.