Vascular stent-graft apparatus and forming method

Abstract

A stent-graft is provided which includes a smooth continuous inside surface for efficient fluid flow therethrough. The stent-graft can be implanted intraluminally by radially expanding the stent-graft adjacent an area within the body lumen to be treated, or can be implanted utilizing direct surgical techniques. A cylindrical support structure is preferably provided which is at least partially embedded along with portions of the film. The cylindrical support structure can facilitate radial expansion and provide additional structural strength to the stent-graft. A woven fabric support structure can also be embedded within the film of solid material forming the stent-graft to provide additional support to the stent-graft and allow suturing of the stent-graft to walls of the body lumen. Various different geometric configurations can be provided for the stent-graft. To form the stent-graft a mandrel is placed within a vacuum and a film of material, such as parylene, is deposited upon the mandrel. Additional layers of parylene film can be deposited to embed at least portions of the cylindrical support structure and/or the woven fabric support structure within the film of parylene forming the stent-graft. A coupling system including a collar with a circumferential groove can similarly be embedded within the stent-graft by deposition of additional layers of parylene film. Separate bands can reside within the groove partially and hold a portion of the wall of the lumen between the band and the groove of the collar to secure an end of the stent-graft adjacent the lumen.