PREDICT-PVI Understanding Peripheral Restenosis: Genomic and Proteomic Determinants of Vascular Intervention

Inclusion Criteria: 1. Age of at least 18 years. 2. Provision of written informed consent for biospecimen storage, broad genetic and proteomic analysis of tissues, without restrictions, and correlation with clinical outcome data. 3. Willingness to undergo all study collection procedures and sample analyses . VG BYPASS COHORT 1\. Patient requires placement of an infrainguinal vein bypass graft for the treatment of chronic peripheral artery occlusive disease (PAD). Disabling claudication or critical limb ischemia are acceptable indications. 2\. Adequate vein conduit (saphenous vein or alternative vein/spliced vein grafts) for bypass available based on preoperative surgical and/or ultrasound assessment. SFA COHORT: 1. Patient requires placement of a superficial femoral artery stent for the treatment of chronic peripheral artery occlusive disease (PAD). Disabling claudication or critical limb ischemia are acceptable indications. 2. TransAtlantic Intersociety Consensus (TASC) A-C lesions (must be \>70% by visual estimate) amenable to bare metal or drug-eluting stent placement. Stent manufacturer is at the discretion of the treating physician; stents to be used must be commercially available and, if drug-eluting, FDA-approved for SFA use . 3. Must have at least one patent outflow vessel to the foot. Exclusion Criteria: 1. Anticipated life expectancy less than 2 years. 2. Undergoing active treatment for advanced malignancy (e.g. metastatic disease). 3. On immunosuppressive therapy for solid organ transplant or other indications. 4. Known or suspected hypercoagulable state. 5. Unable or unwilling to be compliant with the follow-up assessments. VG BYPASS COHORT 1. Use of any non-autogenous conduit or revision of a pre-existing graft. 2. Bypass performed for other than chronic atherosclerotic occlusive disease (e.g. arteritis, aneurysm, acute limb ischemia or trauma). 3. Combined endovascular intervention during same procedure (i.e. hybrid procedure) except for treatment of ipsilateral TASC A/B iliac disease. SFA STENT COHORT 1. Stent placement performed for other than chronic atherosclerotic occlusive disease (e.g. arteritis, aneurysm, acute limb ischemia, or trauma). 2. TASC D disease (total SFA occlusion or occlusion with severe calcification not amenable to stent placement). 3. Previous SFA stent placement. 4. Use of stent graft. 5. Lesions requiring stent placement \> 1cm below the tibial plateau. 6. Known or suspected allergy to nickel. 7. Pregnancy. \-