Bifurcation Stent Assembly

Abstract

A stent assembly comprises a stent and a side branch flap. The stent has a substantially tubular body which defines a primary lumen and is comprised of a plurality of interconnected stent members. Adjacent stent members define a plurality of stent openings that extend through the body and which are in fluid communication with the primary lumen. At least one stent opening is a side branch opening. The side branch flap is a non-tubular body having a planar structure. A first region of the planar structure is overlappingly positioned across a portion of the side branch opening prior to deployment. A second region of the planar structure is engaged to a portion of the body of the stent immediately adjacent to the perimeter of the side branch opening. When the assembly is deployed the first region of the flap is displaced radially outward from the side branch opening.

1 . A bifurcation stent assembly having an undepolyed configuration and a deployed configuration, the bifurcation stent comprising:
 a stent having a substantially tubular body, a first end, a second end and an intermediate portion therebetween;   the tubular body comprising a plurality of interconnected stent members defining a side branch opening disposed along the intermediate portion of the stent; and   a first side branch flap comprising first and second regions; the first and second regions having a wall thickness, wherein the wall thickness of the first region is thinner than the wall thickness of the second region, and wherein in the undeployed configuration the first side branch flap overlaps at least a portion of the side branch opening.   
   
   
       2 . The bifurcation stent assembly of  claim 1 , further comprising a second side branch flap. 
   
   
       3 . The bifurcation stent assembly of  claim 2 , wherein the side branch opening comprises a proximal side and a distal side, and wherein the first and second side branch flaps, in combination, are disposed about both the proximal side and the distal side of the side branch opening. 
   
   
       4 . The bifurcation stent assembly of  claim 2 , wherein the first side branch flap comprises a different shape than the second side branch flap. 
   
   
       5 . The bifurcation stent assembly of  claim 2 , wherein the first side branch flap and the second side branch flap are substantially diametrically opposed to one another across the side branch opening. 
   
   
       6 . The bifurcation stent assembly of  claim 2 , wherein at least one of the first and second side branch flaps comprises a biocompatible material. 
   
   
       7 . The bifurcation stent assembly of  claim 2 , wherein at least one of the first and second side branch flaps comprises a metal or combination of metals. 
   
   
       8 . The bifurcation stent assembly of  claim 1 , wherein the first side branch flap is substantially planar. 
   
   
       9 . The bifurcation stent assembly of  claim 1 , wherein the first side branch flap comprises a plurality of cells. 
   
   
       10 . The bifurcation stent assembly of  claim 9 , wherein the second region has larger cells than the first region. 
   
   
       11 . The bifurcation stent assembly of  claim 1 , wherein the first side branch flap comprises a shape memory material. 
   
   
       12 . The bifurcation stent assembly of  claim 1 , wherein in the undeployed configuration, the first side branch flap takes on a substantially cowl-like shape in the deployed configuration. 
   
   
       13 . The bifurcation stent assembly of  claim 1 , wherein the first side branch flap comprises a radiopaque coating. 
   
   
       14 . A stent delivery system for delivering a bifurcation stent assembly having an undeployed configuration and a deployed configuration, the stent delivery system comprising:
 a catheter having a catheter shaft and a stent retaining region, the catheter shaft defining a primary guidewire lumen;   a primary guidewire disposed in the primary guidewire lumen;   an expandable balloon;   a secondary guidewire; and   a stent having a substantially tubular body, a first end, a second end and an intermediate portion therebetween;   the tubular body comprising a plurality of interconnected stent members defining a side branch opening disposed along the intermediate portion of the stent; and   a first side branch flap comprising first and second regions; the first and second regions having a wall thickness, wherein the wall thickness of the first region is thinner than the wall thickness of the second region, and wherein in the undeployed configuration the first side branch flap overlaps at least a portion of the side branch opening.   
   
   
       15 . The stent delivery system of  claim 14 , further comprising a second side branch flap. 
   
   
       16 . The stent delivery system of  claim 15 , wherein the secondary guidewire is disposed between the first side branch flap and the second side branch flap. 
   
   
       17 . The stent delivery system of  claim 15 , wherein in the undeployed configuration, the first and second side branch flaps take on a substantially cowl-like shape in the deployed configuration. 
   
   
       18 . The stent delivery system of  claim 14 , wherein the first side branch flap comprises a plurality of cells, and wherein the second region has larger cells than the first region. 
   
   
       19 . The stent delivery system of  claim 14 , wherein the expandable balloon comprises a first region and a second region; the first having different expansion characteristics than the second region, wherein the first region is disposed adjacent to the side branch opening.