Peripheral Vascular Surgery Society

Fernanda S. Mazzariol, MD, Enrico Ascher, MD, Anil Hingorani, MD, Marcel Scheinman, MD, Prasad Gade, MD, Sreedhar Kalakuri, MD, William Yorkovich, RPA, and Sergio Salles-Cunha, PhD.

Purpose: To prospectively evaluate whether DU can reliably replace standard arteriography (SA) in the preoperative assessment of candidates for popliteal and infrapopliteal arterial bypasses.

Methods: This was a two-phase study undertaken at our institution from July 1997 to February 1998. Phase I, designed to evaluate the accuracy of DU when compared to SA, involved 55 ischemic lower limbs (50 patients) in which complete visualization of the arterial system from the common femoral technique were eliminated from this analysis. Disabling claudication was the indication for the workup in 3 limbs (8%) and critical ischemia in 37 (92%). Phase II was initiated following the analysis of results in Phase I, where inflow and outflow bypass sites were chosen based solely on DU findings. This phase included 30 lower limbs (29 patients) initially subjected to DU only. An attempt to visualize the aorta and iliac arteries with DU was also made. Indications for surgery were claudication in 3 (10%) patients and critical ischemia in 27 (90%).

Results: In Phase I, DU correctly identified significant occlusive disease proximal to the inguinal ligament in 4 out of 40 cases (10%) when based on common femoral artery wave form analysis. In only one case (2.5%), DU failed to reveal a significant common iliac artery stenosis as confirmed by SA. Selection of outflow bypass site by SA revealed 10 popliteal arteries, 26 infrapopliteal arteries and 4 unreconstructable cases. DU correctly identified 9 (90%) popliteal arteries, 24 (92%) infrapopliteal arteries and agreed with the latter group. In Phase II, the DU exam lasted from 45 to 135 minutes (average 98 minutes). In this phase, 26 infrainguinal bypasses (14 popliteals; 12 infrapopliteals), in conjunction with 5 ipsilateral iliac balloon angioplasties with stents, were successfully performed in 26 patients based on preoperative DU findings alone. Completion angiograms obtained in all cases were found to correlate well with the preoperative DU findings. In the remaining 4 cases, SA was deemed necessary because of non-visualization of an adequate outflow artery (3) and severe arterial wall calcification (1). In 3, SA confirmed the DU findings and all patients underwent major amputations. The remaining patient underwent a vein bypass successfully constructed to a calcified anterior tibial artery. The most difficult areas to access by DU were the first portion of the anterior tibial artery and the bifurcation of the tibioperoneal trunk. Local factors (edema, obesity, arterial wall calcification and uncooperative patients) added to the difficulty of the examination. These factors were found in 17 of the 70 patients studied (24%).

Conclusions: Carefully performed DU exam may avert the need for SA (26 of 30 procedures). The results of this study can be used as an impetus to initiate larger, multi-center protocols to further evaluate this newer non-invasive approach for patients presenting with severe lower limb ischemia.