Catheter apparatus and methods for treating vasculatures

Abstract

A catheter apparatus may have a flexible shaft, guidewire lumens passing through the shaft, and a positioning device for positioning the guidewires relative to an external lumen. The positioning device may be an expansible scaffold covered with a retractable sheath. The positioning device may also be one or more balloons that are inflated through an inflation port in the shaft. The catheter apparatus may be operated by inserting a guide catheter into a vasculature with a chronic total occlusion, inserting the catheter apparatus into the guide catheter, and advancing the guidewires through the guidewire lumens and into contact with a chronic total occlusion. The positioning device may be activated before and/or between attempts to pass the guidewires through the chronic total occlusion to interrogate various parts of the chronic total occlusion.

1 . A catheter apparatus comprising:
 a flexible shaft,   guidewire lumens passing longitudinally through the shaft, and   a positioning means for positioning distal ends of the guidewire lumens relative to an inner wall of an external lumen.   
     
     
         2 . The apparatus of  claim 1 , further comprising a retractable sheath surrounding the guidewire lumens. 
     
     
         3 . The apparatus of  claim 1 , wherein the positioning means is an expansible scaffold. 
     
     
         4 . The apparatus of  claim 3 , wherein the guidewire lumens are coupled to the expansible scaffold. 
     
     
         5 . The apparatus of  claim 1 , wherein the positioning means is one or more sponges. 
     
     
         6 . The apparatus of  claim 5 , wherein the guidewire lumens are embedded in the one or more sponges. 
     
     
         7 . The apparatus of  claim 1 , wherein the positioning means is a shape-memory means integrated with the guidewire lumens. 
     
     
         8 . The apparatus of  claim 1 , wherein the positioning means is a deflectable tip. 
     
     
         9 . The apparatus of  claim 1 , wherein the positioning means is one or more balloons. 
     
     
         10 . The apparatus of  claim 9 , wherein the one or more balloons are inflated through an inflation port running longitudinally in the shaft. 
     
     
         11 . The apparatus of  claim 9 , wherein the one or more balloons is a balloon with a substantially planar distal surface. 
     
     
         12 . The apparatus of  claim 11 , wherein the guidewire lumens are extruded through the distal surface of the balloon. 
     
     
         13 . The apparatus of  claim 9 , wherein the one or more balloons surround distal ends of the guidewire lumens. 
     
     
         14 . The apparatus of  claim 1 , wherein the positioning means is a rotatable core within the shaft. 
     
     
         15 . The apparatus of  claim 1 , wherein the guidewire lumens are adapted to be positioned eccentrically relative to an inner wall of an external lumen. 
     
     
         16 . A method of operating a catheter apparatus comprising:
 providing a catheter apparatus comprising:
 a flexible shaft, 
 guidewire lumens passing longitudinally through the shaft, and 
 a positioning means, 
 inserting a guide catheter into a vasculature with a chronic total occlusion, 
 inserting the catheter apparatus into the guide catheter, activating the positioning means for positioning distal ends of the guidewire lumens relative to the chronic total occlusion, and 
 advancing guidewires through the guidewire lumens and into contact with the chronic total occlusion. 
   
     
     
         17 . The method of  claim 16 , further comprising withdrawing the catheter apparatus from the vasculature and not withdrawing the guidewires. 
     
     
         18 . The method of  claim 16 , further comprising withdrawing the guidewires from contact with the chronic total occlusion and advancing the guidewires through the guidewire lumens into contact with the chronic total occlusion repeatedly at different locations until a suitable site for passing the guidewires through the chronic total occlusion is found. 
     
     
         19 . The method of  claim 18 , further comprising activating the positioning means before each advancing the one or more guidewires through the one or more guidewire lumens into contact with the chronic total occlusion. 
     
     
         20 . The method of  claim 16 , wherein the positioning means is an expansible distal end. 
     
     
         21 . The method of  claim 16 , wherein the positioning means is a deflectable tip on the one or more guidewires. 
     
     
         22 . The method of  claim 16 , wherein the positioning means is a rotatable core within the shaft. 
     
     
         23 . The method of  claim 16 , wherein the positioning means is adapted to position the distal ends of the guidewire lumens eccentrically relative to the chronic total occlusion.