Expandable stent and method for delivery of same

Abstract

An expandable stent comprising a proximal end and a distal end in communication with one another and a tubular wall disposed between the proximal end and the distal end. The tubular wall has a longitudinal axis and a porous surface defined by a plurality of intersecting members comprising a series of longitudinal struts disposed substantially parallel to the longitudinal axis of the stent. Each longitudinal strut in the series comprises flexure means for substantially complementary extension and compression of a diametrically opposed pair of the longitudinal struts upon flexure of the stent. The stent is expandable from a first, contracted position to a second, expanded position upon the application of a radially outward force on the stent. The provision of such flexure means in the series of longitudinal struts leads to a very desirable balance of lateral flexibility of the unexpanded stent and radial rigidity of the expanded stent.

What is claimed is:  
     
         1 . An expandable stent comprising a proximal end and a distal end in communication with one another, a tubular wall disposed between the proximal end and the distal end, the tubular wall having a longitudinal axis and a porous surface defined by a plurality of intersecting members comprising a series of longitudinal struts disposed substantially parallel to the longitudinal axis of the stent, each of the longitudinal struts comprising flexure means for substantially complementary extension and compression of a diametrically opposed pair of the longitudinal struts upon flexure of the stent, the stent being expandable from a first, contracted position to a second, expanded position upon the application of a radially outward force on the stent.  
     
     
         2 . The stent defined in  claim 1 , wherein the flexure means at least one lateral section disposed in each longitudinal strut.  
     
     
         3 . The stent defined in  claim 2 , wherein the at least one lateral section comprises a pointed apex.  
     
     
         4 . The stent defined in  claim 2 , wherein the at least one lateral section comprises a rounded apex.  
     
     
         5 . The stent defined in  claim 2 , wherein the at least one lateral section comprises a flat apex.  
     
     
         6 . The stent defined in  claim 1 , wherein the flexure means at least first lateral section and second lateral section disposed in each longitudinal strut.  
     
     
         7 . The stent defined in  claim 6 , wherein the first lateral section and the second lateral section are symmetric.  
     
     
         8 . The stent defined in  claim 6 , wherein the first lateral section and the second lateral section are asymmetric.  
     
     
         9 . The stent defined in  claim 8 , wherein the first lateral section and the second lateral section have substantially the same shape and differing size.  
     
     
         10 . The stent defined in  claim 8 , wherein the first lateral section and the second lateral section have differing shape and size.  
     
     
         11 . The stent defined in any one of claims  6 - 10 , wherein the first lateral section and the second lateral section have substantially the same shape and differing size.  
     
     
         12 . The stent defined in any one of claims  1 - 11 , wherein the plurality of intersecting members are arranged to define a first repeating pattern comprised of a polygon having a pair of side walls substantially parallel to the longitudinal axis and the flexure means is disposed in each of the side walls..  
     
     
         13 . The stent defined in  claim 12 , wherein the flexure means comprises an S-shaped portion.  
     
     
         14 . The stent defined in any one of claims  12 - 13 , wherein the S-shaped portion comprises a pair of joined curved sections wherein each curve section has an arc of about 180°.  
     
     
         15 . The stent defined in any one of claims  12 - 13 , wherein the S-shaped portion comprises a pair of joined curved sections wherein each curved section has an arc of greater than 180°.  
     
     
         16 . The stent defined in any one of claims  14 - 15 , wherein the curved sections are of substantially the same size.  
     
     
         17 . The stent defined in any one of claims  14 - 15 , wherein the curved sections are of different size.  
     
     
         18 . The stent defined in any one of claims  1 - 17 , wherein the series of longitudinal struts comprising the flexure means includes all longitudinal struts in the porous surface.  
     
     
         19 . The stent defined in any one of claims  1 - 18 , wherein the stent is constructed of stainless steel.  
     
     
         20 . The stent defined in any one of claims  1 - 18 , wherein the stent is constructed of a self-expanding material.  
     
     
         21 . The stent defined in  claim 20 , wherein the self-expanding material is nitinol.  
     
     
         22 . The stent defined in  claim 20 , wherein the self-expanding material expands at a temperature of greater than about 30° C.  
     
     
         23 . The stent defined in  claim 20 , wherein the self-expanding material expands at a temperature of in the range of from about 30° to about 40° C.