Method of recapturing a stent

Abstract

A method to retrieve a deployed stent in a blood vessel. In one embodiment, the method includes the introduction of a retrieval stent within the lumen of the deployed stent, enlarging the retrieval stent to contact a surface of the deployed stent and contracting the retrieval stent which in turn causes the deployed stent to contract for removal from the blood vessel. The retrieval stent may contain one or more fluid passageways through which heated or cooled fluid can circulate and may be connected to a catheter for circulation of the fluid. Fluid flow may be regulated by a valve or valve assembly incorporated in the stent and/or the catheter.

1 . A method of retrieving a stent, comprising: 
 positioning a portion of a first stent within a lumen of a second stent residing at a first location in a blood vessel;    contacting a surface of the second stent with the first stent; and    translating the first and second stents away from the first location.    
   
   
       2 . The method according to  claim 1 , wherein the first stent is comprised of a shape-memory material and the contacting step comprises the step of expanding the first stent from a contracted diameter to an expanded diameter by circulating heated fluid through a fluid flow conduit of the first stent, the method further comprising the step of contracting the first and second stents concomitantly by delivering a cryogenic fluid to the first stent.  
   
   
       3 . The method according to  claim 1 , wherein the first stent is connected to a catheter comprising a valve for controlling fluid flow to and from the first stent, the contacting step comprising the step of delivering fluid through the catheter and valve to the first stent to expand the first stent.  
   
   
       4 . The method according to  claim 3 , wherein the first stent comprises a single fluid pathway having a first end and a second end in fluid communication respectively with a first and second lumen of the catheter, the delivering step comprising circulating fluid through the first stent by delivering fluid from the catheter first lumen to the first end of the first stent and from the second end of the first stent to the catheter second lumen.  
   
   
       5 . The method according to  claim 3 , wherein the first stent comprises a first and second fluid pathway in fluid communication respectively with a first and second lumen of the catheter, the delivering step comprising circulating fluid through the first stent by delivering fluid from the catheter first lumen to the first fluid pathway of the first stent and from the second fluid pathway of the first stent to the catheter second lumen.  
   
   
       6 . The method according to  claim 5 , wherein the first and second fluid pathways are connected at a distal end of the first stent, the circulating step comprising fluid from the first fluid pathway entering the second fluid pathway at the distal end of the first stent.  
   
   
       7 . The method according to  claim 1 , wherein the first stent is connected to a catheter comprising a valve assembly for delivering fluid to and from the first stent, the valve assembly comprising a first and second hollow member configured for insertion through a diaphragm of the first stent, the first and second hollow member being in fluid communication with a first and second lumen of the catheter, the contacting step comprising the step of delivering fluid through the first lumen of the catheter and the first hollow member to the first stent to expand the first stent.  
   
   
       8 . The method according to  claim 7 , wherein the delivering step further comprises removing fluid from the first stent through the second hollow member and through the second lumen of the catheter.  
   
   
       9 . The method according to  claim 1 , wherein the first and second stents are comprised of a shape memory material, further comprising the step of collapsing the first and second stents concomitantly, following the contacting step.  
   
   
       10 . The method according to  claim 9 , wherein the first and second stents are comprised of a shape memory metal, wherein the collapsing step comprises the step of introducing a cryogenic fluid into the first stent.  
   
   
       11 . The method according to  claim 10 , wherein the first stent is connected to a catheter comprising a valve for controlling fluid flow to and from the first stent, the contacting step comprising the step of delivering fluid through the catheter and valve to the first stent to expand the first stent.  
   
   
       12 . The method according to  claim 11 , wherein the first stent comprises a single fluid pathway having a first end and a second end in fluid communication respectively with a first and second lumen of the catheter, the delivering step comprising circulating fluid through the first stent by delivering fluid from the catheter first lumen to the first end of the first stent and from the second end of the first stent to the catheter second lumen.  
   
   
       13 . The method according to  claim 11 , wherein the first stent comprises a first and second fluid pathway in fluid communication respectively with a first and second lumen of the catheter, the delivering step comprising circulating fluid through the first stent by delivering fluid from the catheter first lumen to the first fluid pathway of the first stent and from the second fluid pathway of the first stent to the catheter second lumen.  
   
   
       14 . The method according to  claim 13 , wherein the first and second fluid pathways are connected at a distal end of the first stent, the circulating step comprising fluid from the first fluid pathway entering the second fluid pathway at the distal end of the first stent.  
   
   
       15 . The method according to  claim 9 , wherein the first stent is connected to a catheter comprising a valve assembly for delivering fluid to and from the first stent, the valve assembly comprising a first and second hollow member configured for insertion through a diaphragm of the first stent, the first and second hollow member being in fluid communication with a first and second lumen of the catheter, the contacting step comprising the step of delivering fluid through the first lumen of the catheter and the first hollow member to the first stent to expand the first stent.  
   
   
       16 . The method according to  claim 15 , wherein the delivering step further comprises removing fluid from the first stent through the second hollow member and through the second lumen of the catheter.  
   
   
       17 . The method according to  claim 1 , wherein the contacting step comprises expanding the first stent from a contracted diameter to an expanded diameter by heating the first stent, the method further comprising the step of contracting the first and second stents concomitantly to a diameter smaller than the expanded diameter by cooling the first stent.  
   
   
       18 . A method of retrieving a stent, comprising: 
 positioning a portion of a first shape memory stent attached to a catheter within a lumen of a second shape memory stent deployed in a blood vessel;    delivering heated fluid from the catheter to the first stent to cause the first stent to expand from a contracted diameter to an expanded diameter, a surface of the first stent contacting a surface of the second stent;    introducing a cryogenic fluid into the first stent to cause the first and second stents to contract to a removal diameter; and    removing the first and second stents from the blood vessel.    
   
   
       19 . A stent comprising a non-inflatable non-porous tubing, including at least one fluid flow conduit therein, the tubing being circumferentially arranged to form a side wall of the stent, thereby creating a main lumen of the stent through which blood can flow.  
   
   
       20 . The stent according to  claim 19 , wherein the stent is comprised of a shape memory material.  
   
   
       21 . The stent according to  claim 20 , wherein the shape memory material comprises a metal.  
   
   
       22 . The stent according to  claim 20 , wherein the shape memory material comprises a plastic.  
   
   
       23 . The stent according to  claim 19 , further comprising: 
 a removable catheter including a proximal end that remains outside of a patient's body and a distal end that is capable of sealing attachment to the stent for fluid delivery to the stent; and    a valve for controlling the flow of fluid in the system.    
   
   
       24 . The stent according to  claim 23 , wherein the valve comprises a back flow preventer.