PERIPHERAL VASCULAR-SURGERY WITH MAGNETIC-RESONANCE ANGIOGRAPHY AS THE SOLE PREOPERATIVE IMAGING MODALITY

Purpose: Magnetic resonance angiography (MRA) is a developing techniqu e that provides arteriograms without the risks associated with iodinat ed contrast and arterial puncture or the expense of hospitalization. p rior reports have demonstrated the accuracy of peripheral vessel MRA f or evaluation of the aorta through pedal vessels. This study sought to determine whether vascular reconstructions could be planned and accom plished on the basis of MRA alone. Methods: Eighty consecutive candida tes for bypass with ischemic rest pain or tissue loss were studied wit h preoperative outpatient MRA of the juxtarenal aorta through the foot . Confirmation of MRA findings was provided by intraoperative intraart erial pressure measurements for proximal vessels and postbypass arteri ography for the runoff. Life-table analysis of graft patency and limb salvage was performed. Results: Two patients could not tolerate MRA an d required contrast arteriography, but all others underwent reconstruc tive procedures on the basis of MRA alone (11 aortobifemoral, 67 infra inguinal). Intraoperative findings regarding suitability of inflow and outflow vessels confirmed the accuracy of the MRAs in every case. MRA indicated that none of the patients undergoing infrainguinal bypass h ad significant inflow occlusive disease, and this was confirmed at ope ration with pressure measurements of inflow vessels that were always w ithin 10 mm Hg (peak systolic) of systemic pressure. The results of in traoperative completion arteriography and preoperative MRAs were ident ical for ah but two patients who had minor discrepancies. All aortobif emoral reconstructions remained patent, and all limbs remained intact. The infrainguinal reconstructions had an 84% limb salvage rate and 78 % primary graft patency rate at 21 months. Comparison of charges for p atients undergoing preoperative MRA versus contrast angiography showed a cost savings of $1288 for each patient treated with preoperative MR A alone. Conclusions: MRA is a noninvasive, cost-effective outpatient imaging technique that, if properly performed and interpreted, is suff icient for planning peripheral bypass procedures. Its use may supplant contrast arteriography in many patients.