Claudication, Intermittent

Subjects with a known diagnosis of peripheral artery disease as measured by an abnormal ankle brachial index (\<.9 or \>1.1) will undergo a single 5 min exposure of 670 nm light, 1 cm above the gastrocnemius muscle. Blood flow will be measured by infusion of ultrasound contrast and subsequent acquisition of ultrasound images. 2 blood samples will be collected for measurement of nitric oxide metabolites.

The goal of this observational study is to learn whether activation of the GLP-1 receptor could represent a therapeutic target by characterizing its expression and associated inflammatory mechanisms in patients with peripheral artery disease, according to disease severity, in adults with symptomatic lower-limb peripheral arterial disease. The main questions it aims to answer are: * Is the level of GLP-1 receptor (GLP1R) expression on peripheral blood mononuclear cells (PBMC) different between patients with intermittent claudication (ischemia of effort) and those with chronic limb-threatening ischemia? * Is GLP1R expression associated with inflammatory and oxidative profiles of PBMC? * Can GLP-1 receptor agonists reverse inflammatory and oxidative alterations induced by plasma from patients with peripheral artery disease in endothelial cell cultures? * Are there specific plasma proteomic signatures associated with GLP1R overexpression? Researchers will compare patients with intermittent claudication to patients with chronic limb-threatening ischemia to see if disease severity is associated with differences in GLP1R expression, PBMC inflammatory/oxidative phenotype, and plasma proteomic profiles. Participants will: * Provide an additional blood sample (15 mL) collected during a routine, clinically indicated blood draw * Have PBMC isolated for measurement of GLP1R expression and assessment of inflammatory and oxidative markers * Have plasma analyzed for proteomic profiling and used in in-vitro endothelial cell experiments Participation ends after completion of the blood sampling, and no additional procedures beyond standard clinical care are required.

The goal of this clinical trial is to assess the effects of passive calf muscle stretching in patients diagnosed with peripheral artery disease (PAD). The main question it aims to answer are: 1. To determine if daily calf muscle stretching at home improves calf muscle and vascular health. 2. To determine if daily calf muscle stretching at home improves walking performance. Participants will use inflatable ankle splints for 30 minutes a day, 5 days a week for 4-weeks on both days and 4-weeks of no stretching.

The aim of the study is to evaluate whether walking capacity in patients with intermittent claudication is improved more by home-based 5+ exercise training than by current recommendations of daily walking.

This study evaluates the effect of additional hyperbaric oxygen therapy after lower extremity amputation. The patients will be randomized after amputation to either a treatment group receiving hyperbaric oxygen therapy, or control group.

The purpose of this clinical trial is to analyze patency after autologous infrainguinal bypass surgery in patients receiving a venous conduit versus a covered venous conduit.