Conditions: Peripheral Arterial Disease
Keywords: saphenous vein bypass grafts flow-mediated vasodilation
Allocation: NA | Intervention model: SINGLE_GROUP
Enrollment: 19
Healthy volunteers: no

Brief summary:
This study will determine whether or not saphenous vein \[arterial\] bypass grafts in the leg relax in response to increases in blood flow.

Detailed description:
Subjects who have undergone saphenous vein \[arterial\] bypass grafts from the femoral to above-knee popliteal artery will undergo ultrasound imaging at rest, and again after 5 minutes of blood pressure cuff occlusion of the calf. (at 1 minute and 15 minutes) Subjects will then be given sub-lingual nitroglycerin, and repeat ultrasound will be performed 3 minutes later. Following 10 minutes of rest, subjects will be given intravenous L-NMMA, a specific nitric oxide inhibitor, to help determine the responsible agent of the vein graft flow mediated dilation.

Arms:
arm 1: ultrasound imaging of saphenous vein bypass graft following an ischemic stimulus, administration of sublingual nitroglycerin and intravenous administration of L-NMMA.

Interventions: intervention 1: L-N^G monomethyl arginine (L-NMMA)
Intervention descriptions: intervention 1: L-NMMA was infused at a dose of 1 mg/kg over 10 minutes to competitively inhibit the production of nitric oxide. Ultrasound imaging of the saphenous vein \[arterial\] bypass at baseline, and following an ischemic stimulus, administration of sublingual nitroglycerin, and intravenous administration of L-NMMA.

Protocol document: