Balloon catheter

Abstract

A method of manufacturing a balloon portion for a balloon catheter for radially expanding a vessel in the body of a mammal, which catheter comprises a tube portion with a passage therethrough and a hollow expandable balloon portion defined by a fluid impervious wall and secured to the tube portion, which balloon portion can be inflated and deflated by means of a fluid passed through the passage, such that: a. the wall of the balloon portion is formed from a flexible substantially fluid impervious material having reinforcing fibers formed integrally with the wall material; and b. the balloon portion is preformed to the desired radial diameter at its inflated state having smaller diameter end portions and a wider diameter portion intermediate the said ends and has a substantially uniform wall thickness.

1 . A balloon member for use with a catheter for radially expanding a vessel in the body of a mammal, the balloon member comprising: 
 a flexible, hollow intermediate portion located between terminal portions which have a diameter smaller than the intermediate portion, the intermediate portion including a fluid impervious wall of a substantially uniform thickness, the intermediate portion having a deflated state and a maximum radially expanded state;    reinforcing fibers in a braided arrangement provided integrally with the intermediate portion, the braided reinforcing fibers oriented at an angle with an axis of the intermediate portion that is less than a critical angle when the intermediate member is in the deflated state and that is at the critical angle when the intermediate portion is at the maximum radially expanded state, whereby the diameter of the intermediate portion at the maximum radially expanded state exceeds the diameter of the intermediate portion at the deflated state by no more than 15%, such that the balloon member is semi-compliant.    
     
     
         2 . The balloon member recited in  claim 1  wherein the reinforcing fibers are formed of a polymer.  
     
     
         3 . The balloon member recited in  claim 1 , wherein the reinforcing fibers have shape memory.  
     
     
         4 . The balloon member recited in  claim 1 , wherein the reinforcing fibers are metallic.  
     
     
         5 . The balloon member recited in  claim 1 , wherein the braided fibers are in the form of opposed helices.  
     
     
         6 . The balloon member recited in  claim 1 , wherein the intermediate portion is formed of a polyurethane.  
     
     
         7 . The balloon member recited in  claim 1  wherein the intermediate portion has an external diameter between 1 and 10 mm.  
     
     
         8 . The balloon member recited in  claim 1  further including a catheter having a passage, wherein the terminal portions of the balloon member are secured to the catheter and the intermediate portion is in communication with the passage, whereby the intermediate portion can be inflated by a fluid passed through the passage.  
     
     
         9 . The balloon member recited in  claim 1  wherein the diameter of the intermediate portion at the maximum radially expanded state exceeds the diameter of the intermediate portion in the deflated state by 5-15%.