Safety and effectiveness of the Phoenix Atherectomy System in lower extremity arteries: Early and midterm outcomes from the prospective multicenter EASE study

Objectives To evaluate the novel Phoenix Atherectomy System as percutaneous treatment of de novo and restenotic infrainguinal arterial lesions. Methods This prospective, multicenter, nonrandomized investigational device exemption trial was conducted across 16 US and German centers between August 2010 and April 2013. Intention-to-treat enrollment was 128 patients (mean age: 71.8 years, 59% male) with 149 lesions (mean length: 34 mm, mean diameter stenosis: 89.5%), and the primary analysis per-protocol population consisted of 105 patients with 123 lesions. The primary efficacy endpoint, technical success, was the achievement of acute debulking with a post-atherectomy residual diameter stenosis 50% (before adjunctive therapy). The primary safety endpoint was the major adverse event (MAE) rate through 30 days. Results For the primary analysis per-protocol population, the rate of lesion technical success was 95.1% (117/123), with the lower limit of the 95% CI 90.6%, meeting the prospectively established target performance goal of 86%. After post-atherectomy adjunctive therapy, residual stenosis was 30% for 99.2% (122/123) of lesions (mean final diameter stenosis 10.5%). Improvement of 1 Rutherford class occurred for 74.5% of patients through 30 days and for 80% through six months. MAEs were experienced by 5.7% (6/105) of patients through 30 days (with the upper limit of the 95% CI 11.0%, meeting the target performance goal of <20%), and 16.8% through six months. Six-month freedom from TLR and TVR was 88.0% and 86.1%, respectively. Conclusions Based on the high rate of technical success and the low rates of MAEs through six months, the Phoenix Atherectomy System is safe and effective for the debulking of lower-extremity arterial lesions.