Multiple independent nested stent structures and methods for their preparation and deployment

Abstract

Blood vessels and other body lumens are stented using stent structures comprising a plurality of radially expansible rings where at least some of the rings comprise axially extending elements which interleave with axially extending elements on adjacent unconnected rings. The ring structures may be open cell structures or closed cell structures, and the axially extending elements will typically be formed as part of the open cell or closed cell structure.

1 . A tubular prosthesis comprising:
 a plurality of tubular rings radially expandable from a contracted configuration to an expanded configuration, each ring comprising a plurality of struts interconnected so as to form a circumferential series of closed cells,   wherein a pair of adjacent tubular rings each have an axially oriented curved end strut and wherein the pair of adjacent tubular rings are axially coupled together at a location by the merging of the apices of the axially oriented curved end struts.   
   
   
       2 . The tubular prosthesis of  claim 1 , wherein the axially oriented curved end strut in a first tubular ring of the pair has a first width and the axially oriented curved end strut in a second tubular ring of the pair has a second width, and the location where the first and second adjacent tubular rings merge together has a width no greater than the sum of the first and second widths. 
   
   
       3 . The tubular prosthesis of  claim 1 , wherein said cells are I-shaped or H-shaped. 
   
   
       4 . The tubular prosthesis of  claim 1 , wherein a pair of adjacent, circumferentially spaced apart closed cells in a ring are coupled together with a circumferentially oriented connector. 
   
   
       5 . The tubular prosthesis of  claim 1 , wherein at least some of the plurality of interconnected struts define an upper axial element and a lower axial element on one end of at least one of the tubular rings. 
   
   
       6 . The tubular prosthesis of  claim 5 , wherein the upper and lower axial elements are coupled together with one or more circumferential struts. 
   
   
       7 . The tubular prosthesis of  claim 5 , wherein the upper and lower axial elements define a receptacle for receiving an upper or lower axial element on an adjacent tubular prosthesis. 
   
   
       8 . The tubular prosthesis of  claim 7 , wherein the adjacent tubular prosthesis is axially separable from the plurality of tubular rings in the contracted configuration. 
   
   
       9 . The tubular prosthesis of  claim 6 , wherein the one or more circumferential struts define a circumferential slot therebetween. 
   
   
       10 . The tubular prosthesis of  claim 9 , wherein the circumferential slot is bounded by an inner circumferential strut and an outer circumferential strut. 
   
   
       11 . The tubular prosthesis of  claim 5 , wherein the struts of the upper axial element define an axially oriented slot. 
   
   
       12 . The tubular prosthesis of  claim 5 , wherein the upper axial element is bounded by an upper axial strut, a lower axial strut, a curved inner end strut and a curved outer end strut. 
   
   
       13 . The tubular prosthesis of  claim 5 , wherein the struts of the lower axial element define an axially oriented slot. 
   
   
       14 . The tubular prosthesis of  claim 5 , wherein the lower axial element is bounded by an upper axial strut, a lower axial strut, a curved inner end strut and a curved outer end strut. 
   
   
       15 . The tubular prosthesis of  claim 5 , wherein the struts of the upper axial element form a circumferentially oriented shoulder, the shoulder adapted to engage an axial element on an adjacent tubular prosthesis and prevent axial movement thereof. 
   
   
       16 . The tubular prosthesis of  claim 15 , wherein the shoulder comprises an upper and a lower lateral protrusion. 
   
   
       17 . The tubular prosthesis of  claim 5 , wherein the struts of the lower axial element form a circumferentially oriented shoulder, the shoulder adapted to engage an axial element on an adjacent tubular prosthesis and prevent axial movement thereof. 
   
   
       18 . The tubular prosthesis of  claim 17 , wherein the shoulder comprises an upper and a lower lateral protrusion. 
   
   
       19 . The tubular prosthesis of  claim 5 , wherein the upper axial element comprises an upper shoulder laterally extending therefrom and the lower axial element comprises a lower shoulder laterally extending therefrom, the upper shoulder facing the lower shoulder so as to form a narrow entrance to the receptacle and create an abutment for an upper or lower axial element on an adjacent tubular prosthesis. 
   
   
       20 . The tubular prosthesis of  claim 19 , wherein the abutment inhibits axial movement of the adjacent tubular prosthesis, thereby maintaining axial spacing between the two adjacent tubular prostheses. 
   
   
       21 . The tubular prosthesis of  claim 1 , further comprising a therapeutic agent carried by the tubular prosthesis and adapted to being released therefrom at a controlled rate. 
   
   
       22 . The tubular prosthesis of  claim 21 , wherein the therapeutic agent inhibits restensosis. 
   
   
       23 . The tubular prosthesis of  claim 1 , wherein the tubular rings comprise a metal. 
   
   
       24 . The tubular prosthesis of  claim 1 , wherein the tubular prosthesis is balloon expandable. 
   
   
       25 . The tubular prosthesis of  claim 1 , further comprising a second radially expandable tubular prosthesis adjacent the plurality of tubular rings and unconnected thereto, the second prosthesis being axially separable from the plurality of tubular rings when both the second prosthesis and the plurality of tubular rings are in the contracted configuration. 
   
   
       26 . The tubular prosthesis of  claim 25 , wherein an end of the second tubular prosthesis interleaves with an adjacent end of the plurality of tubular rings. 
   
   
       27 . The tubular prosthesis of  claim 25 , further comprising a third tubular prosthesis unconnected to but deployable with the plurality of tubular rings or with the second tubular prosthesis, the third tubular prosthesis being axially separable from both the plurality of tubular rings and the second tubular prosthesis when the second tubular prosthesis, the third tubular prosthesis and the plurality of tubular rings are in the contracted configuration.