Patent ID: 7273485

Claim:
A balloon catheter having an elongated shaft with a proximal and a distal end, and a balloon on a distal shaft section, the elongated shaft comprising: a. an outer tubular member defining at least a section of an inflation lumen in fluid communication with an interior of the balloon, and having a proximal end and a distal end; and b. an inner tubular member defining at least a section of a guidewire lumen, extending in at least a distal section of the outer tubular member and extending in the interior of the balloon, the inner tubular member having a proximal end, a distal end distal to the distal end of the outer tubular member, a length, a bonded portion along which an outer surface of the inner tubular member is bonded to an inner surface of the outer tubular member, a proximal portion proximal to the bonded portion extending from the proximal end of the inner tubular member distally to the bonded portion, and a distal portion distal to the bonded portion extending distally from the bonded portion at least through the balloon interior from a proximal to a distal end of the balloon interior, the proximal portion of the inner tubular member having an axial compression stiffness less than an axial compression stiffness of the distal portion of the inner tubular member, such that a stiffness transition of the proximal portion to the distal portion of the inner tubular member is at the bonded portion.