Analysis of endovascular therapy for femoropopliteal disease with the Supera stent

Abstract

The structural limitations of currently available laser-cut nitinol stents in the highly diseased arterial system of the lower extremity are well described. These devices are frequently used in long-segment occlusions, at the adductor hiatus, and across the knee into the popliteal artery and tibial-peroneal trunk despite concerns related to the high mobility of the knee joint and the potential for external stent compression, fractures, and occlusion. The Supera stent (Abbott Vascular, Santa Clara, Calif) was developed to provide superior radial strength, fracture resistance, and flexibility compared with laser-cut nitinol stents. This study represents the initial U.S. experience in the management of lower extremity artery atherosclerotic disease with the Supera interwoven wire stent. Patients undergoing stent implantation in the 20-month period after the 2008 Food and Drug Administration clearance were included. Medical records, radiographic imaging, and procedural data were examined. Procedural angiograms were classified according to TransAtlantic Inter-Society Consensus criteria. Patency and limb loss rates were calculated using Kaplan-Meier analysis. There were 305 stents implanted in 147 patients. Clinical follow-up was a mean of 12.7months (range, 0.2-33.7months), and radiologic follow-up was a mean of 8.4months (range, 0.2-26.8months). Most patients had critical limb ischemia, with tissue loss (38.1%) or rest pain (28.6%) as the indication for intervention. Of the 147 patients, 75 (51.02%) underwent a concomitant adjunctive procedure in the treated extremity. Primary, assisted primary, andsecondary patency rates at 12months by duplex ultrasound imaging were 89.8%, 91.2%, and 93.2%, respectively, byKaplan-Meier estimates, with a mean lesion length of 184.5± 131.80mm and mean stented length of 197.5±113.65mm. Seventeen patients experienced an event requiring successful reintervention in the stented segment (13 for type I or II restenosis; four for type III). There were eight major amputations, with five of those eight having a patent stent at the time of limb sacrifice. The overall mortality was 11.6% during the study period. Knee radiography was performed in 47 patients with devices extending into the popliteal and tibial-peroneal segment, and no stent fractures were identified. Stenting of the superficial femoral and popliteal arteries using the Supera stent system appears to be safe and effective. The interwoven stent design may better serve areas under extreme mechanical stress. Our results with thispopulation of highly diseased patients including very long lesion lengths are consistent with outcomes of other publications reporting the use of this device.