Purpose: To report the 12- and 24-month results after directional atherectomy (DA) of below-the-knee (BTK) arterial lesions with the SilverHawk device.
Methods: Forty-nine BTK lesions in 36 patients (58% men; mean age 70+/-11 years) with peripheral occlusive disease of the lower limbs were treated with DA; 19 (53%) of the limbs were classified with Rutherford-Becker 4 or 5 ischemia. Target lesions were in the popliteal artery (n = 6, 12%), tibioperoneal trunk (n = 25, 51%), peroneal artery (n = 10, 20%), anterior tibial artery (n = 5, 10%), and posterior tibial artery (n = 3, 6%). Nine (18%) lesions were located in a stent. Twelve lesions extended to 2 artery segments. The average degree of diameter stenosis was 89%+/-10% (range 70%-100%); there were 11 (22%) occlusions. The mean lesion length was 48+/-28 mm.
Results: Sixteen (33%) lesions were treated after predilation; 33 (67%) lesions were treated with primary DA. All but 1 (2%) lesion could be treated with DA. In 19 (39%) lesions, additional balloon angioplasty was performed, and 2 (4%) lesions required stent implantation as a result of dissection. The mean stenosis diameter after DA was 12%+/-18% (range 0%-100%). After additional therapy, the mean stenosis diameter was 8%+/-9% (range 0%-100%). A residual stenosis </ or 30% was achieved in 48 (98%) lesions. The mean ankle-brachial index significantly increased from 0.48+/-0.26 to 0.81+/-0.32 (p<0.05) before discharge and remained improved during follow-up. Primary and secondary patency rates were 67% and 91% after 1 year and 60% and 80% after 24 months. The 12- and 24-month cumulative event-free survival rates (primary patency) by Kaplan-Meier analysis were 58%+/-8% and 46%+/-9%; at the same time intervals, the cumulative survival rates (secondary patency) were 88%+/-6% and 73%+/-9%, respectively.