Intra-arterial digital angiography: a new diagnostic method for determining limb salvage bypass candidates.

Twenty patients with chronic arterial disease of a lower extremity underwent standard angiography to determine whether distal bypass surgery could be performed for limb salvage (seven had pain at rest and 13 had breakdown of ischemic skin). Standard angiography provided anatomic detail of the aortoiliac and proximal femoral arteries in all cases, but even with 7 minutes of cuff-induced reactive hyperemia, angiography failed to demonstrate the status of the tibial vessels and the plantar arcade.l Digital subtraction angiography (with intra-arterially injected contrast medium) demonstrated a patent popliteal artery with at least one patent tibial vessel communicating with the distal arcade in 14 of 20 ischemic extremities (70%). Intra-arterial digital angiography (IDA) confirmed absent distal runoff or unreconstructable tibial arterial segments with absent plantar arch communications in six limbs (30%). Fourteen patients underwent distal artery bypass because of additional information provided by IDA (femoropopliteal, 7; femorotibial-peroneal, 4; sequential, 3). Three of the remaining six patients with occluded or unreconstructable distal disease had amputations, and three underwent local profundoplasty. Intraoperative angiograms confirmed the patency of occult arteries in the distally reconstructed limbs. This small series suggests that failure to visualize distal vasculature in ischemic patients by standard angiography is usually a technical problem and that bypass surgery is possible in many patients who might otherwise be considered for amputation.