Endoluminal prosthesis placing method

The present invention provides devices and methods for the endoluminal placement of prostheses, particularly within the vascular system for the treatment of cardiovascular disease, such as vascular stenoses, dissections, aneurysms, and the like. The apparatus and methods, however, are also useful for placement in other body lumens, such as the ureter, urethra, biliary tract, gastrointestinal tract and the like, for the treatment of other conditions which may benefit from the introduction of a reinforcing or protective structure within the body lumen. The prostheses will be placed endoluminally. As used herein, "endoluminally" will mean placement by percutaneous or cutdown procedures, wherein the prosthesis is transluminally advanced through the body lumen from a remote location to a target site in the lumen. In vascular procedures, the prostheses will typically be introduced "endovascularly" using a catheter over a guidewire under fluoroscopic guidance. The catheters and guidewires may be introduced through conventional access sites to the vascular system, such as through the femoral artery, or brachial and subclavian arteries, for access to the target site. A catheter assembly includes a coiled endoluminal prosthesis () and a catheter () having at least first and second telescoping shafts (). The prosthesis is releasably engaged to the distal ends () of the telescoping shafts. The prosthesis is capable of assuming a second, expanded diameter state from a first, reduced diameter state. The length and number of turns () of the coiled prosthesis can be changed by the relative translation and rotation of the shafts. The catheter assembly is especially useful for placing a coiled stent graft (), in which one turn () of the prosthesis has a greater pitch than the adjacent turns, at the intersection () of a bifurcation within a blood vessel (). Remotely viewable marker elements () may be used and include a marker element (A, ) configured to indicate orientation as well as axial position of the prosthesis. The ends of the prosthesis may be substantially less stiff than the remainder of the prosthesis and/or shaped to help prevent tissue trauma.