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

Abstract

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. ClinicalTrials.gov identifier NCT01541774.