Angioplasty catheter system with adjustable balloon length

Abstract

A resizable inflatable balloon, primarily for use with balloon catheters. The resizable inflatable balloon comprises a first portion and an adjacent second portion. The first portion is inflatable to a working diameter at a first pressure while the second portion does not substantially expand at the first pressure. The second portion does expand to the working diameter at a second pressure greater than the first pressure, so that subsequent inflation at the first pressure inflates the first portion and the second portion to the working diameter. The methods of resizing the inflatable members include placing the inflatable balloon in a mold and supplying inflation fluid to expand the second member to the working diameter. In practice, a catheter having the resizable inflatable balloon is guided through a patient's vasculature until the inflatable balloon is positioned in a desired region. Inflation fluid is supplied at the first pressure to inflate the first portion to the working diameter. The catheter is withdraw and the inflatable balloon is resized as described above. The catheter is reintroduced to the patient's vasculature and inflation fluid is then supplied at the first pressure to inflate both the first and second portions.

What is claimed is:  
     
         1 . A resizable inflatable balloon, comprising: 
 a) a first portion having at least a length that is expandable to a working diameter at a first pressure; and    b) a second portion longitudinally adjacent the first portion that is not substantially expandable at the first pressure and is expandable to the working diameter at a second pressure greater than the first pressure, so that subsequent inflation at the first pressure expands the first portion and the second portion to the working diameter.    
     
     
         2 . The resizable inflatable balloon of  claim 1  wherein the first pressure is about 14 to about 16 atmospheres.  
     
     
         3 . The resizable inflatable balloon of  claim 2  wherein the second pressure is about 18 to about 30 atmospheres.  
     
     
         4 . The resizable inflatable balloon of  claim 1  wherein the resizable inflatable balloon is formed from a polymeric material having a Shore durometer hardness of about 60D to about 85D.  
     
     
         5 . The resizable inflatable balloon of  claim 1  wherein the resizable inflatable balloon is formed from a thermoplastic polyurethane.  
     
     
         6 . The resizable inflatable balloon of  claim 5  wherein the thermoplastic polyurethane is a polyurethane block copolymer having a Shore durometer hardness of about 65D to about 75D.  
     
     
         7 . The resizable inflatable balloon of  claim 1  wherein the resizable inflatable balloon is formed from a thermoplastic elastomeric polyester.  
     
     
         8 . The resizable inflatable balloon of  claim 7  wherein the thermoplastic elastomeric polyester is a copolyester having a Shore durometer hardness of about 63D to about 82D.  
     
     
         9 . The resizable inflatable balloon of  claim 1  wherein the resizable inflatable balloon is formed from a thermoplastic elastomeric block copolymer.  
     
     
         10 . The resizable inflatable balloon of  claim 9  wherein the thermoplastic elastomeric block copolymer is a polyether block amide copolymer having a Shore durometer hardness of about 63 to about 72D.  
     
     
         11 . The resizable inflatable balloon of  claim 1  wherein the first portion is from about 10 to about 50 millimeters long.  
     
     
         12 . The resizable inflatable balloon of  claim 1  wherein the first portion has a length of about 10 to about 30 millimeters.  
     
     
         13 . The resizable inflatable balloon of  claim 1  wherein the second portion has a length of about 10 to about 50 millimeters.  
     
     
         14 . The resizable inflatable balloon of  claim 1  wherein the second portion has a length of about 20 to about 40 millimeters.  
     
     
         15 . The resizable inflatable balloon of  claim 11  wherein the working diameter is about 1.5 to about 4.0 millimeters.  
     
     
         16 . The resizable inflatable balloon of  claim 1  wherein the second portion has a greater wall thickness than the first portion prior to expansion of the second portion at the second pressure.  
     
     
         17 . The resizable inflatable balloon of  claim 1  having a third portion between the first portion and the second portion that is not substantially expandable at the first pressure or at the second pressure.  
     
     
         18 . A balloon catheter, comprising 
 a) a catheter shaft having an outer tubular member having proximal and distal ends and an lumen extending therein, and an inner tubular member disposed within the lumen of the outer tubular member and having proximal and distal ends and a lumen extending therein; and    b) a resizable balloon on a distal section of the catheter shaft, comprising a first portion expandable to a working diameter at a first pressure, and a second portion longitudinally adjacent to the first portion that is not substantially expandable at the first pressure and is expandable to the working diameter at a second pressure greater than the first pressure, so that subsequent inflation at the first pressure expands the first portion and the second portion to the working diameter.    
     
     
         19 . The balloon catheter of  claim 18  wherein the first portion of the balloon is distal to the second portion of the balloon.  
     
     
         20 . The balloon catheter of  claim 18  wherein the first portion of the balloon is proximal to the second portion of the balloon.  
     
     
         21 . The balloon catheter of  claim 19  wherein the balloon has a distal end secured to the inner tubular member and a proximal end secured to the outer tubular member at a location proximal to the distal end of the outer tubular member.  
     
     
         22 . The balloon catheter of  claim 21  wherein the distal end of the outer tubular member extends distally within the balloon to a distal end of the second portion.  
     
     
         23 . A kit for resizing inflatable tubular member comprising a catheter having: 
 a) a resizable inflatable tubular member with a first portion that is expandable to a working diameter at a first pressure and a second portion longitudinally adjacent the first portion that is not substantially expandable at the first pressure and is expandable to the working diameter at a second pressure greater than the first pressure, so that subsequent inflation at the first pressure expands the first portion and the second portion to the working diameter; and    b) a mold having a cavity having a diameter which is approximately the working diameter, and having a length which is longer than the first portion.    
     
     
         24 . The kit of  claim 23  further comprising at least one additional mold, each mold having a cavity with a different length.  
     
     
         25 . A method for resizing an inflatable tubular member, comprising: 
 a) positioning within a cavity of a first mold a resizable inflatable tubular member having a first portion with a length and a working diameter at a first pressure, and having a second portion longitudinally adjacent the first portion which is not substantially expandable at the first pressure and which is expandable at a second pressure greater than the first pressure, the cavity of the first mold having a length which is greater than the length of the first portion; and    b) supplying inflation fluid at the second pressure to expand at least a section of the second portion of the inflatable tubular member within the first mold.    
     
     
         26 . The method of  claim 25  including: 
 a) positioning the inflatable tubular member within a second mold having a cavity with a second length which is longer than the length of the cavity of the first mold; and  
 b) supplying inflation fluid at the second pressure to expand at least a section of the second portion of the inflatable tubular member within the second mold.  
 
     
     
         27 . A method for performing a medical procedure, comprising: 
 a) advancing through a patient's vasculature an elongated catheter having a resizable inflatable tubular member with a first portion that is inflatable to a first working diameter at a first pressure and a second portion longitudinally adjacent the first portion that is not substantially expandable at the first pressure and is expandable at a second pressure greater than the first pressure;    b) supplying inflation fluid at the first pressure to expand the first portion to the working diameter;    c) withdrawing the catheter from the patient's vasculature;    d) positioning the inflatable tubular member within a mold having a cavity with a length which is longer than the first portion;    e) supplying inflation fluid at the second pressure to expand the second portion of the inflatable tubular member within the mold;    f) advancing the catheter through the patient's vasculature until the inflatable tubular member is disposed within a desired region thereof; and    g) supplying inflation fluid at the first pressure to expand the first portion and the second portion.    
     
     
         28 . The method of  claim 27  wherein the cavity of the mold has a diameter which is at least the first working diameter of the first portion, and wherein step (g) comprises expanding the first portion and the second portion to at least the first working diameter of the first portion.