Endoluminal expansion system

Abstract

An endoprosthesis expansion system having, in combination, a delivery component such as a length of catheter tubing having at its distal end an intermediate sheath component, and an inner tube within the full length of the delivery catheter and intermediate sheath component. The inner tube has a protrusion affixed to its distal end, and an expandable endoprosthesis is fitted in a compacted state about the intermediate sheath, immediately proximal to the protrusion. If the endoprosthesis is a self-expanding endoprosthesis (as is preferred), an exterior constraining sheath is required around the outer surface of the endoprosthesis. Following insertion of the endoprosthesis and delivery system into a body conduit (such as a blood vessel) and transport of the endoprosthesis to the desired site within the body conduit, the endoprosthesis is deployed by axially moving the protrusion against the system, thereby applying a radially directed outward force and causing simultaneous dilatation of the intermediate sheath and disruption of the exterior constraining sheath. Disruption of the exterior constraining sheath, in the case of a self-expanding prosthesis, releases the stored energy in the formerly constrained prosthesis, allowing it to expand and accomplish full deployment against the luminal surface of the body conduit at the desired site.

We claim:  
     
         1 . An endoluminal expansion system comprising: 
 a) a protrusion affixed to an elongate actuation member, said protrusion having a maximum diameter of D 2 ;    b) a substantially tubular sheath mounted coaxially about the elongate actuation member, said elongate actuation member being axially movable with respect to the substantially tubular sheath, said substantially tubular sheath having an inside diameter of D 1 , wherein D 2  is greater than D 1 ; and    c) an expandable endoprosthesis affixed coaxially about the substantially tubular sheath wherein one end of said expandable endoprosthesis is adjacent to said protrusion.    
     
     
         2 . An endoluminal expansion system according to  claim 1  wherein said endoprosthesis is a self-expanding endoprosthesis and is contained within a disruptable constraining sheath.  
     
     
         3 . An endoluminal expansion system according to  claim 2  wherein said constraining sheath is configured to be an implantable constraining sheath.  
     
     
         4 . An endoluminal expansion system according to  claim 2  wherein said constraining sheath is configured to be a removable constraining sheath.  
     
     
         5 . An endoluminal expansion system according to  claim 2  wherein said constraining sheath is disruptable via a row of perforations.  
     
     
         6 . An endoluminal expansion system according to  claim 2  wherein said constraining sheath comprises porous expanded polytetrafluoroethylene.  
     
     
         7 . An endoluminal expansion system according to  claim 6  wherein said constraining sheath comprises a delicate constraining sheath contained within a packaging sheath that is removable prior to insertion of the endoluminal expansion system into a body conduit.  
     
     
         8 . An endoluminal expansion system according to  claim 1  wherein said substantially tubular sheath includes at least one split along its length.  
     
     
         9 . An endoluminal expansion system according to  claim 1  wherein said substantially tubular sheath comprises a polymeric material less than about 0.12 mm thick.  
     
     
         10 . An endoluminal expansion system according to  claim 1  wherein said protrusion comprises a length of tubularly braided wire.  
     
     
         11 . An endoluminal expansion system according to  claim 1  wherein said protrusion comprises an inflatable member.  
     
     
         12 . An endoluminal expansion system according to  claim 1  wherein said elongate actuation member comprises a tube.  
     
     
         13 . An endoluminal expansion system according to  claim 1  wherein said elongate actuation member comprises an elongate tensile member  
     
     
         14 . An endoluminal expansion system according to  claim 13  wherein said elongate tensile member comprises a guidewire.  
     
     
         15 . An endoluminal expansion system according to  claim 1  wherein said system incorporates a tether element.  
     
     
         16 . An endoluminal expansion system according to  claim 1  wherein said substantially tubular sheath includes an enlargement at its distal end.  
     
     
         17 . An endoluminal expansion system according to  claim 16  wherein said enlargement is a collar.  
     
     
         18 . An endoluminal expansion system according to  claim 1  wherein, following the application of axial compression against an end of the substantially tubular sheath by the protrusion, the substantially tubular sheath assumes a corrugated shape.  
     
     
         19 . An endoluminal expansion device comprising: 
 a protrusion and an associated actuation member, the protrusion having a maximum diameter of D 1 ;    a substantially tubular sheath through which the actuation member moves, the substantially tubular sheath having a maximum diameter of D 2 , D 2  being less than D 1 ,    wherein when the protrusion is moved against the substantially tubular sheath, the substantially tubular sheath is dilated to cause an expansion force.    
     
     
         20 . An endoluminal expansion device according to  claim 19  wherein the substantially tubular sheath includes at least one split along at least a portion of its length.  
     
     
         21 . An expandable endoprosthesis and delivery device comprising the endoprosthesis mounted on a substantially tubular sheath; wherein the delivery device comprises a protrusion and an associated actuation member, the protrusion being proportioned to enlarge the endoprosthesis when the protrusion is actuated against the substantially tubular sheath and endoprosthesis.  
     
     
         22 . An endoluminal expansion system according to  claim 21  wherein said endoprosthesis is a self-expanding endoprosthesis and is contained within a disruptable constraining sheath.  
     
     
         23 . An endoluminal expansion system according to  claim 22  wherein said constraining sheath is disruptable via a row of perforations.  
     
     
         24 . An endoluminal expansion system according to  claim 23  wherein said constraining sheath comprises porous expanded polytetrafluoroethylene.  
     
     
         25 . An endoluminal expansion system according to  claim 24  wherein said constraining sheath comprises a delicate constraining sheath contained within a packaging sheath that is removable prior to insertion of the endoluminal expansion system into a body conduit.  
     
     
         26 . An endoluminal expansion system according to  claim 21  wherein said substantially tubular sheath includes at least one split along its length.  
     
     
         27 . An endoluminal expansion system according to  claim 21  wherein said substantially tubular sheath comprises a polymeric material less than about 0.12 mm thick.  
     
     
         28 . A method of expanding an expandable endoluminal prosthesis wherein said endoprosthesis is part of a delivery system comprising: 
 a) a protrusion affixed to an elongate actuation member, said protrusion having a maximum diameter of D 2 ;    b) a substantially tubular sheath mounted coaxially about the elongate actuation member, said elongate actuation member being axially movable with respect to the substantially tubular sheath, said substantially tubular sheath having an inside diameter of D 1 , wherein D 2  is greater than D 1 ; and    c) an expandable endoprosthesis affixed coaxially about the substantially tubular sheath wherein one end of said expandable endoprosthesis is adjacent said protrusion;    said method comprising moving said elongate actuation member and protrusion against said substantially tubular sheath and expandable endoprosthesis, thereby applying a radially outwardly directed force to the endoprosthesis and thereby initiating expansion of the endoprosthesis.    
     
     
         29 . A method according to  claim 28  wherein said substantially tubular sheath includes at least one split along its length.  
     
     
         30 . A method according to  claim 28  wherein said expandable endoprosthesis is a self-expanding endoprosthesis contained within a disruptable constraining sheath.  
     
     
         31 . A method according to  claim 30  wherein said constraining sheath is configured as an implantable constraining sheath.  
     
     
         32 . A method according to  claim 30  wherein said constraining sheath is configured as a removable constraining sheath.  
     
     
         33 . A method according to  claim 30  wherein said constraining sheath comprises porous expanded polytetrafluoroethylene.  
     
     
         34 . A method according to  claim 30  wherein said constraining sheath is disruptable via a row of perforations extending along a length of the constraining sheath.  
     
     
         35 . A method according to  claim 34  wherein said constraining sheath comprises porous expanded polytetrafluoroethylene.  
     
     
         36 . A method according to  claim 30  wherein said constraining sheath comprises a delicate constraining sheath contained within a packaging sheath that is removable prior to insertion of said endoprosthesis into a body conduit.  
     
     
         37 . An endoluminal expansion system comprising: 
 a) an elongate actuation member having a distal end;    b) a substantially tubular sheath mounted coaxially about the elongate actuation member, said elongate actuation member being axially movable with respect to the substantially tubular sheath, wherein the substantially tubular sheath has a distal end that is secured to the distal end of the elongate actuation member; and    c) an expandable endoprosthesis affixed coaxially about the substantially tubular sheath;    wherein the application of tension to the elongate actuation member applies compression to the substantially tubular sheath whereby a radially outward force is applied to the expandable endoprosthesis by the substantially tubular sheath.    
     
     
         38 . An endoluminal expansion system according to  claim 37  wherein said endoprosthesis is a self-expanding endoprosthesis and is contained within a disruptable constraining sheath.  
     
     
         39 . An endoluminal expansion system according to  claim 38  wherein said constraining sheath is disruptable via a row of perforations.  
     
     
         40 . An endoluminal expansion system according to  claim 38  wherein said constraining sheath comprises porous expanded polytetrafluoroethylene.  
     
     
         41 . An endoluminal expansion system according to  claim 38  wherein said constraining sheath comprises a delicate constraining sheath contained within a packaging sheath that is removable prior to insertion of the endoluminal expansion system into a body conduit.  
     
     
         42 . An endoluminal expansion system according to  claim 37  wherein said elongate actuation member comprises a tube.  
     
     
         43 . An endoluminal expansion system according to  claim 37  wherein said elongate actuation member comprises an elongate tensile member  
     
     
         44 . An endoluminal expansion system according to  claim 43  wherein said elongate tensile member comprises a guidewire.  
     
     
         45 . An endoluminal expansion system according to  claim 37  wherein said system incorporates a tether element.  
     
     
         46 . An endoluminal expansion system according to  claim 37  wherein said substantially tubular sheath includes an enlargement at its distal end.  
     
     
         47 . An endoluminal expansion system according to  claim 46  wherein said enlargement is a collar.  
     
     
         48 . An endoluminal expansion system according to  claim 37  wherein the application of compression to the substantially tubular sheath causes the substantially tubular sheath to assume a corrugated shape.  
     
     
         49 . An endoluminal expansion system comprising an endoprosthesis and a delivery catheter having a balloon affixed at a distal end thereof, said system including a tether secured to the delivery catheter, wherein said tether includes a length that is captive between the balloon and the endoprosthesis.  
     
     
         50 . An endoluminal expansion system according to  claim 49  wherein inflation of the balloon results in expansion and deployment of the endoprosthesis and wherein said length of tether is not captive following inflation and subsequent deflation of the balloon.