Method and apparatus for delivering a stent into a body lumen

Abstract

The invention is a method and apparatus for delivering a stent, including, but not limited to, a self expanding stent, into a body lumen. The apparatus comprises an outer tube having a proximal end and a distal end and sized to hold a stent therein in a radially constricted condition, an inner tube within the outer tube and having a proximal end and a distal end, and a holding element comprising one or more inflatable balloons carried on the inner tube at the location of the loaded stent. The balloon can be inflated prior to the procedure so that the balloon presses against the inner surface of the outer tube trapping the stent in its longitudinal position between the inner and outer tubes. Accordingly, the outer tube can be slid proximally to release the stent or distally to retract the stent back into the delivery device without the stent inadvertently sliding.

1 . An apparatus for delivering a self expanding stent into a body lumen comprising: 
 an outer tube having a proximal end and a distal end and sized to hold a self-expanding stent therein in a radially constricted condition;    an inner tube within said outer tube having a proximal end and a distal end;    a stent in a radially constricted state within said outer tube; and    an inflated and permanently sealed balloon fixedly mounted on said inner tube and positioned within said outer tube so that at least a portion of said stent is longitudinally contiguous with at least a portion of said balloon and presses said stent against said outer tube, said balloon being more compliant than said outer tube, whereby said stent has a greater resistance to longitudinal motion relative to said balloon than to longitudinal motion relative to said outer tube.    
   
   
       2 . The apparatus of  claim 1  wherein said balloon is formed of polyurethane.  
   
   
       3 . The apparatus of  claim 1  wherein said balloon is formed of silicone.  
   
   
       4 . The apparatus of  claim 1  wherein said stent is a self-expanding stent.  
   
   
       5 . The apparatus of  claim 1  wherein said balloon is inflated sufficiently to hold said stent stationary relative to said outer tube when said inner tube is moved longitudinally relative to said inner tube.  
   
   
       6 . The apparatus of  claim 1  wherein said balloon has a length about equal to a length of said stent and wherein said stent is longitudinally aligned with said balloon.  
   
   
       7 . The apparatus of  claim 1  wherein said balloon is shorter than said stent, said stent having a proximal end and a distal end and wherein said stent is positioned so that said balloon is adjacent said proximal end of said stent.  
   
   
       8 . The apparatus of  claim 1  wherein said balloon comprises first and second balloons and wherein said stent is positioned so that said first balloon is adjacent said proximal end of said stent and said second balloon is adjacent said distal end of said stent.