Rotating stent delivery system for side branch access and protection and method of using same

A system for treatment of a vessel bifurcation, the system comprising:

• a catheter, the catheter having a catheter shaft, the catheter shaft defining an inflation lumen therethrough, a portion of the catheter shaft characterized as an axle portion, the axle portion defining a fluid opening, the fluid opening being in fluid communication with the inflation lumen;
• and
• a rotatable assembly mounted to the catheter and providing a fluid seal with the catheter that permits relative rotation between the catheter and the rotatable assembly, the rotatable assembly comprising a barrel, the barrel defining a substantially hollow longitudinal passage through which the axle portion extends, the rotatable assembly further comprising an expandable medical balloon sealingly disposed about the barrel, the balloon being expandable between a reduced state and an expanded state, wherein in the expanded state the balloon has a diameter greater than that in the reduced state, the barrel further defining at least one fluid port, the at least one fluid port being in fluid communication with the substantially hollow passage and an interior of the balloon;
• wherein the catheter shaft further comprises a proximal region and a distal region, the axle portion positioned between the proximal region and the distal region, at least a portion of the proximal region immediately adjacent to the axle portion having a diameter greater than that of the substantially hollow longitudinal passage of the barrel and at least a portion of the distal region immediately adjacent to the axle portion having a diameter greater than that of the substantially hollow longitudinal passage of the barrel;
• wherein the proximal region of the catheter shaft and the barrel define a proximal gap therebetween and wherein the distal region of the catheter shaft and the barrel define a distal gap therebetween;
• the system wherein the balloon comprises a proximal overlap region and a distal overlap region:
• the proximal overlap region extending from the rotatable assembly to radially overlap a portion of the proximal region of the shaft, during expansion of the balloon the proximal overlap region is sealingly engaged to the portion of the proximal region of the shaft thereby forming a fluid tight seal over the proximal gap between the barrel and the proximal region of the shaft;
• the distal overlap region extending from the rotatable assembly to radially overlap a portion of the distal region of the shaft, during expansion of the balloon the distal overlap region is sealingly engaged to the portion of the distal region of the shaft thereby forming a fluid tight seal over the distal gap between the barrel and the distal region of the shaft.