Intravascular device and method of manufacture and use

Abstract

An intravascular device and method of constructing an intravascular device. The device has a proximal portion which is stiffer than a distal portion. The device of the present invention may also be advanced through small vessels without the aid of a guidewire although a guidewire may be used when necessary. The device may be manufactured in a number of different ways and a preferred method is to use an expanded PTFE liner at the distal portion and an etched PTFE liner along the proximal portion. The device also has a number of different jacket sections, preferably at least four, with increasing durometer towards the proximal end and a braided section with varying pic along the length.

1 . A method of forming an intravascular device, comprising the steps of: 
 mounting an expanded PTFE liner over a first mandrel portion;    winding a reinforcing layer over the expanded PTFE liner after the mounting step; and    applying a first jacket over the reinforcing layer and expanded PTFE liner after the winding and mounting steps.    
   
   
       2 . The method of  claim 1 , further comprising the steps of: 
 covering the jacket, reinforcing layer and expanded PTFE liner with a shrink tube;    fusing the coating layer to the expanded PTFE liner to form an integrated structure; and    removing the shrink tube after the fusing step.    
   
   
       3 . The method of  claim 1 , wherein: 
 the applying step is carried out by positioning a tube of material over the reinforcing layer.    
   
   
       4 . The method of  claim 1 , further comprising the steps of: 
 positioning an etched PTFE liner over a second mandrel portion; and    the winding step is carried out with the reinforcing layer being wound over the etched PTFE liner; and    the applying step is carried out with the jacket layer being positioned over the reinforcing layer and the etched PTFE liner after the winding step.    
   
   
       5 . The method of  claim 4 , wherein: 
 the applying steps are carried out with the jacket layer having a first jacket section and a second jacket section, the first jacket section being positioned over the expanded PTFE liner and the second jacket section being positioned over the etched PTFE liner, the first jacket section having a durometer which is at least 30 D less than the second jacket section.    
   
   
       6 . The method of  claim 5 , wherein: 
 the applying steps are carried out with the first jacket section having a durometer which is at least 40 D less than the second jacket section.    
   
   
       7 . The method of  claim 1 , wherein: 
 the positioning steps are carried out with the expanded PTFE liner having a porosity of 8-10 microns.    
   
   
       8 . The method of  claim 4 , wherein: 
 the first mandrel portion and second mandrel portion are part of the same mandrel.    
   
   
       9 . The method of  claim 1 , further comprising the step of: 
 inverting an end of the expanded PTFE liner at a distal end.    
   
   
       10 . The method of  claim 9 , wherein: 
 the inverting step is carried out to form an inverted portion of the expanded PTFE liner which extends longitudinally at least 0.5 mm from a distal end of the reinforcing element.    
   
   
       11 . An intravascular device, comprising: 
 a liner layer having a first liner section, the first liner section being made of expanded PTFE;    a reinforcing layer wound over the liner layer; and    a jacket positioned over the reinforcing layer and fused with the liner layer.    
   
   
       12 - 86 . (canceled)