Midterm Results after Atherectomy-assisted Angioplasty of Below-Knee Arteries with Use of the Silverhawk Device

Abstract

Prospective evaluation of the 3- and 6-month results after atherectomy of below-knee arterial lesions with a reference diameter of at least 2.0 mm with use of the Silverhawk device. Fifty-two below-knee lesions in 33 patients (61% men; mean age, 70 years +/- 11) with chronic peripheral occlusive disease of the lower limbs were treated with directional atherectomy. Target lesions were the popliteal artery (segment 3), n = 4 (8%); tibioperoneal trunk, n = 22 (42%); peroneal artery, n = 18 (34%); anterior tibial artery, n = 5 (10%); posterior tibial artery, n = 3 (6%); and in-stent lesions, n = 8 (16%). All interventions were performed via a 6-F sheath. The average degree of diameter stenosis was 89% +/- 10% (range, 70%-100%; n = 12 [23%] occlusions) and the mean lesion length was 48 mm +/- 28. All but one lesion (2%) could be treated with the atherectomy catheter. After additional balloon angioplasty, all but one lesion was treated, with a residual stenosis no greater than 30% (98%), with 7.2 passes per lesion +/- 2.8 (range, 1-12) performed with the device. Fifteen lesions (29%) were treated after predilation and 37 (71%) were treated with primary atherectomy. In 15 lesions (29%), additional balloon angioplasty was performed, and two lesions required stent implantation as a result of dissection. The mean stenosis diameter after atherectomy was 12% +/- 18% (range, 0-100%). After additional therapy, the mean stenosis diameter was 6% +/- 9% (range, 0%-30%). A residual stenosis no greater than 30% was achieved in 50 lesions (96%). The mean ankle-brachial index significantly increased from 0.46 +/- 0.27 to 0.80 +/- 0.34 before discharge and remained improved during follow-up. One procedural complication (3%) was observed in which an intermittent occlusion of the target vessel occurred after an unsuccessful attempt to cross the lesion with the atherectomy device; this was then treated successfully with local lysis. One patient with one treated lesion died during follow-up. The rates of restenosis of at least 70% (diagnosed by duplex ultrasonography) were 14% (seven of 51 lesions) after 3 months and 22% (11 of 51) after 6 months. The 3-month and 6-month cumulative event-free survival were 91% +/- 4.1% and 76.9% +/- 5.8% and the 3-month and 6-month cumulative patency rates were 98% +/- 1.9% and 94.1% +/- 3.3%, respectively. Below-knee native vessel lesions with a diameter of at least 2.0 mm can be treated with the Silverhawk catheter with a high success rate and a low complication rate. Midterm technical and clinical results are encouraging. Additional balloon angioplasty might be necessary in selected cases.