Patent ID: 8206372

Claim:
A catheter, comprising: an outer shaft having a proximal outer section having a distal end, a midshaft section having a distal end and having a proximal end attached to the distal end of the proximal outer section, and a distal outer section having a proximal end attached to the distal end of the midshaft section; wherein the proximal outer section has a first stiffness; wherein the midshaft section has a second stiffness that is less than the first stiffness; wherein the distal outer section has a third stiffness that is less than the second stiffness; an insert disposed within the outer shaft and extending from a first position adjacent to the distal end of the midshaft section to a second position adjacent to the proximal end of the distal outer section, the insert being configured to provide a smooth transition in flexibility between the midshaft section and the distal outer section; an inner shaft disposed within the outer shaft, the inner shaft having a distal tip attached thereto at a joint; a spiral cut transition member disposed about the inner shaft, wherein the spiral cut transition member includes a spiral cut with a pitch that varies along the length of the spiral cut transition member; and a balloon having a proximal waist attached to the outer shaft and a distal waist positioned about the joint.