Method and apparatus for increasing blood flow through an obstructed blood vessel

Abstract

A method of increasing blood flow through an obstructed blood vessel includes providing an expandable member substantially made of a mesh having a plurality of interstices. The expandable member is inserted into the blood vessel, positioned within the blood vessel with the proximal member end upstream of the distal member end and the member body located radially adjacent at least a portion of an obstruction, and expanded to bring at least a portion of the member body into contact with the obstruction. An outward radial force is exerted on the obstruction to dislodge at least one fragment from the obstruction and to enhance blood flow through the blood vessel past the obstruction. The at least one fragment is passed through at least one interstice of the member body in the radial direction, and is selectively retained within the expandable member.

We claim: 
     
         1 . A method of treating an obstructed vessel, the method comprising the steps of:
 positioning an expandable member having a tubular member body substantially made of a mesh having a plurality of interstices within an obstructed vessel radially adjacent to at least a portion of an obstruction in the obstructed vessel, with a proximal end of the tubular member body upstream of a distal end of the tubular member body and the tubular member body;   dislodging at least one fragment from the obstruction by exerting an outward radial force on the obstruction by expanding the expandable member; and   passing the at least one fragment radially inwardly through at least one interstice of the tubular member body.   
     
     
         2 . The method of  claim 1 , wherein at least one of the plurality of interstices is defined by a plurality of strands, and the step of dislodging said at least one fragment from the obstruction comprises the steps of:
 forcing the plurality of strands into penetrating contact with the obstruction; and   separating said at least one fragment from a remaining portion of the obstruction through radial penetration of the strands into the obstruction.   
     
     
         3 . The method of  claim 1 , further comprising breaking said at least one fragment into a plurality of subfragments. 
     
     
         4 . The method of  claim 3 , wherein the step of breaking said at least one fragment into a plurality of subfragments is performed by at least one of a mechanical lysis process and a chemical lysis process. 
     
     
         5 . The method of  claim 1 , wherein the expandable member comprises a self-expanding member, and the step of exerting an outward radial force on the obstruction comprises allowing the self-expanding member to self-expand. 
     
     
         6 . The method of  claim 1 , wherein the step of exerting an outward radial force on the obstruction comprises manually expanding the expandable member. 
     
     
         7 . The method of  claim 1 , further comprising the steps of:
 at least partially collapsing the expandable member; and   removing the expandable member from the blood vessel.   
     
     
         8 . The method of  claim 1 , further comprising the steps of:
 at least partially collapsing the expandable member;   moving the expandable member to a different position with the proximal end of the tubular member body upstream of the distal end of the tubular member body, and the tubular member body located radially adjacent at least a portion of the obstruction; and   exerting an outward radial force on the obstruction by expanding the expandable member.   
     
     
         9 . The method of  claim 8 , further comprising the step of compressing at least a portion of the obstruction.