A bypass is a rerouting of the circulation around an area that is blocked, usually by arterial plaque. Arterial plaque may also be referred to as atherosclerotic plaque.
Most Americans are familiar with coronary coronary artery bypass graft (CABG) surgery, which uses small veins or arteries to get blood around blocked arteries in the heart to improve blood flow. Arterial bypass surgery uses the same principles.
Depending on the size, location, and length of the bypassed artery, these operations may be performed using a segment of vein or artery harvested from the patient, or a synthetic graft made of Teflon or polyester.