Flexible catheter

Abstract

A balloon catheter having improved flexibility in and about its distal end is provided. The flexibility of the catheter is determined in part by improving the properties of a wire or catheter located within the area where the balloon is mounted. In one aspect of the present invention, connecting wires extend through the balloon from the distal end of a catheter body to the proximal end of a core wire. The core wire extends distally away from the connecting wires and the catheter body. In another aspect of the present invention, a core wire is provided having a proximal end extending within the balloon into the catheter tubular body but is not mounted therein. This allows the proximal end of the core wire to “float” within the tubular body, such that when the catheter is advanced through the vasculature of a patient, the core wire may move longitudinally within the tubular body. In another aspect of the present invention, the balloon is mounted over a tubular body which is configured to give the catheter longitudinal flexibility.

What is claimed is:  
     
         1 . A catheter, comprising: 
 an elongate body having a proximal end and a distal end;    at least one connecting wire, the wire having a proximal end and a distal end, the proximal end of the wire being mounted to the distal end of the elongate body and the distal end of the wire extending past the distal end of the elongate body; and    a core wire having a proximal end connected to the distal end of the at least one connecting wire and extending distally therefrom.    
     
     
         2 . The catheter of  claim 1 , further comprising an expandable member having a proximal end mounted to the distal end of the elongate body and a distal end surrounding a proximal portion of the core wire.  
     
     
         3 . The catheter of  claim 1 , wherein two connecting wires connect the elongate body to the proximal end of the core wire.  
     
     
         4 . The catheter of  claim 1 , further comprising a first coil extending from the distal end of the elongate body and surrounding the at least one connecting wire.  
     
     
         5 . The catheter of  claim 4 , further comprising a second coil extending distally from the first coil and surrounding the core wire.  
     
     
         6 . A catheter, comprising: 
 an elongate tubular body having a proximal end and a distal end and a lumen extending therethrough;    an expandable member mounted over the distal end of the tubular body;    a core wire lying along substantially the same longitudinal axis as the tubular body, the core wire having a proximal end and a distal end, the proximal end of the core wire being distally spaced from the distal end of the tubular body outside of the lumen; and    a plurality of connecting wires connecting the distal end of the tubular body to the core wire.    
     
     
         7 . The catheter of  claim 6 , wherein the connecting wires converge distally from the tubular body to the core wire.  
     
     
         8 . The catheter of  claim 6 , wherein each of the connecting wires has flattened ends.  
     
     
         9 . The catheter of  claim 6 , further comprising at least one coil extending from the distal end of the tubular body within the expandable member.  
     
     
         10 . The catheter of  claim 9 , wherein the expandable member has a proximal end mounted over the distal end of the tubular body and a distal end mounted over the coil.  
     
     
         11 . The catheter of  claim 10 , wherein the proximal end of the core wire is positioned within the expandable member.