Bi-directional stent delivery system

Abstract

A stent delivery system includes an inner shaft having a proximal portion and a distal portion, and a radially expandable prosthesis disposed over the inner shaft. The prosthesis has a radially collapsed configuration and a radially expanded configuration, wherein in the collapsed configuration the prosthesis is adapted to be delivered through a vasculature, and in the expanded configuration the prosthesis engages a vessel wall. The stent delivery system also includes an outer shaft having a proximal portion and a distal portion, a shuttle sheath disposed over the radially expandable prosthesis and configured to be in a pre-set locked position with respect to the inner shaft and the outer shaft to operate in a reverse deployment direction.

What is claimed is: 
     
         1 . A stent delivery system, the system comprising:
 an inner shaft having a proximal portion and a distal portion;   a radially expandable prosthesis disposed over the inner shaft, the prosthesis having a radially collapsed configuration and a radially expanded configuration, wherein in the collapsed configuration the prosthesis is adapted to be delivered through a vasculature, and in the expanded configuration the prosthesis engages a vessel wall;   an outer shaft having a proximal portion and a distal portion; and   a shuttle sheath disposed over the radially expandable prosthesis and configured to be in a pre-set locked position with respect to the inner shaft and the outer shaft to operate in a reverse deployment direction.   
     
     
         2 . The system of  claim 1 , wherein in the pre-set locked position, an interference fit is provided between the shuttle sheath and the inner shaft to couple the shuttle sheath to the inner shaft and allow movement in the reverse deploy direction with respect to the outer shaft. 
     
     
         3 . The system of  claim 1 , wherein the prosthesis is a stent and the pre-set locked position defines a reverse deploy stent configuration. 
     
     
         4 . The system of  claim 1 , wherein the pre-set locked position is a position in which the system is supplied to a user such that the radially expandable prosthesis is configured to be deployed in the reverse deployment direction when in the supplied pre-set locked position. 
     
     
         5 . The system of  claim 1 , wherein the shuttle sheath has a proximal portion and a distal portion, the distal portion of the shuttle sheath is locked to the distal portion of the inner shaft via a distal coupling mechanism in the pre-set locked position to define a proximal deployment configuration such that distal advancement of the inner shaft advances the shuttle sheath distally relative to the outer shaft, thereby allowing the prosthesis to radially expand from a proximal end thereof to a distal end thereof. 
     
     
         6 . The system of  claim 5 , wherein the distal coupling mechanism comprises one or more of a snap fit, an interference fit, a barbed connector, a locking mechanism, a rotatable key lock, a linear key lock, a threaded bushing, a twist lock, a magnetic coupling, or a frangible connector. 
     
     
         7 . The system of  claim 5 , wherein the distal portion of the inner shaft is coupled to a nosecone, the distal coupling mechanism locks the distal end of the shuttle sheath with the distal end of the inner shaft via the nosecone. 
     
     
         8 . The system of  claim 1 , wherein the shuttle sheath constrains the prosthesis such that a portion of the prosthesis disposed under a portion of the shuttle sheath is constrained in the radially collapsed configuration at least until the portion of the shuttle sheath is removed from over the portion of the prosthesis to allow to the prosthesis to radially expand to the radially expanded configuration.