Systems and methods for catheter advancement

Abstract

A system can comprise a catheter and a device having an elongate member and an expandable member. The expandable member can be coupled to the elongate member. The elongate member can extend through the catheter. The expandable member can be positioned with a proximal member end proximal to a distal catheter end, a distal member end positioned distal to the distal catheter end, and at least a portion of the expandable member between the distal catheter end and the distal member end in an expanded state in which a maximum transverse dimension of the expandable member is larger than a maximum transverse dimension of the distal member end. The catheter can be advanced in a patient's body with the expandable structure, in the expanded state, at the distal end of the catheter.

1 - 20 . (canceled) 
     
     
         21 . A system comprising:
 a catheter having a lumen;   an elongate manipulation member having a distal section, the elongate manipulation configured to slidably extend through the catheter lumen;   an expandable member coupled to the distal section of the elongate manipulation member, the expandable member comprising a plurality of filaments forming a central portion with a maximum transverse dimension, a proximal portion having a proximally tapering outer dimension, and a distal portion having a distally tapering outer dimension; and   a proximal band attached to a proximal end portion of the expandable member and coupled to the elongate manipulation member.   
     
     
         22 . The system of  claim 21 , wherein the expandable member comprises a plurality of filaments that are braided or woven. 
     
     
         23 . The system of  claim 21 , wherein the expandable member comprises a plurality of filaments formed of wire having a round cross-section. 
     
     
         24 . The system of  claim 21 , wherein the expandable member is self-expanding. 
     
     
         25 . The system of  claim 21 , wherein the proximal band is radiopaque. 
     
     
         26 . The system of  claim 21 , wherein the proximal band comprises a tube with an insider diameter larger than an outside diameter of the elongate manipulation member. 
     
     
         27 . The system of  claim 21 , wherein the elongate manipulation member extends through the expandable member. 
     
     
         28 . The system of  claim 21 , wherein a segment of the elongate manipulation member distal to the expandable member has a curved shape in the absence of any externally applied force. 
     
     
         29 . The system of  claim 21 , wherein the elongate manipulation member extends distally of the expandable member. 
     
     
         30 . The system of  claim 21 , wherein the proximal band is slidably coupled to the elongate manipulation member. 
     
     
         31 . The system of  claim 21 , wherein the proximal band is fixed with respect to the elongate manipulation member. 
     
     
         32 . The system of  claim 21 , wherein the distal portion of the expandable member comprises an outwardly concave section. 
     
     
         33 . A system comprising:
 an elongate manipulation member having a distal section, the elongate manipulation configured to slidably extend through a catheter lumen to position the distal section adjacent a target site within a patient's vasculature;   an expandable member coupled to the distal section of the elongate manipulation member, the expandable member comprising a plurality of filaments forming a central portion disposed between inwardly tapering proximal and distal end portions; and   a proximal band coupling to the proximal end portion of the expandable member to the elongate manipulation member.   
     
     
         34 . The system of  claim 33 , wherein the expandable member comprises a plurality of filaments that are braided or woven. 
     
     
         35 . The system of  claim 33 , wherein the proximal band comprises a tube with an insider diameter larger than an outside diameter of the elongate manipulation member. 
     
     
         36 . The system of  claim 33 , wherein the elongate manipulation member extends through the expandable member. 
     
     
         37 . The system of  claim 33 , wherein a segment of the elongate manipulation member distal to the expandable member has a curved shape in the absence of any externally applied force. 
     
     
         38 . The system of  claim 33 , wherein the proximal band is slidably coupled to the elongate manipulation member. 
     
     
         39 . The system of  claim 33 , wherein the proximal band is fixed with respect to the elongate manipulation member. 
     
     
         40 . The system of  claim 33 , wherein the distal end portion of the expandable member comprises an outwardly concave section.