Coloured angiogram showing a grafted artery (white, across lower centre) running from the right to the left femoral (thigh) arteries in the groin of a 69 year old man. This arterial graft was carried out to bypass a blocked left iliac artery (upper right) and restore normal blood flow. The occlusion of the iliac artery is a result of arteritis, a disease where the walls of arteries become inflamed, usually as a result of infection or autoimmune response.