To demonstrate equivalence in patency performance of GORE-TEX PROPATEN Vascular Grafts and Thin Walled GORE-TEX Stretch Vascular Grafts in a peripheral bypass application to support a claim of substantial equivalence.

Inclusion Criteria:

• Patient requires primary above-knee bypass where the proximal anastomosis will be to the common femoral or proximal superficial femoral artery and the distal anastomosis will be the popliteal artery proximal to the medial head of the gastrocnemius;
• Patient has Grade III or IV occlusive vascular disease;
• Patient has a postoperative life expectancy greater than one year;
• Patient is at least 21 years of age;
• Patient is able to comply with all study requirements and be available for follow-up visits at 1 month, 6 months and 12 months post procedure;
• Patient is willing and able to provide written, informed consent.

Exclusion Criteria:

• Patient had a previous bypass in the diseased extremity (below iliacs);
• Patient has known coagulation disorders including hypercoagulability;
• Patient has had any previous instance of Heparin Induced Thrombocytopenia type 2 (HIT-2) or has known hypersensitivity to heparin;
• Patient has an acute embolic arterial occlusion;
• Patient requires sequential extremity revascularizations or other procedures that require use of additional vascular grafts;
• Patient had percutaneous transluminal angioplasty to the implant site within the previous 30 days;
• Patient is in need of, or is scheduled for, a cardiac surgical procedure or a different vascular surgical procedure;
• Patient has active infection in the region of graft placement; or
• Patient has an incomplete preoperative assessment (as outlined in this protocol) due to an emergency procedure, a traumatic injury or any other reason.