DEFINITIVE Ca++ Study Published for Covidien's SilverHawk/TurboHawk Systems Used with SpiderFX Embolic Protection System

August 15, 2014—Final results from the DEFINITIVE Ca++ trial were published by David Roberts, MD, et al in Catheterization and Cardiovascular Interventions (2014;84:236–244).

The purpose of the DEFINITIVE Ca⁺⁺ study was to evaluate the safety and effectiveness of directional atherectomy and distal embolic protection using Covidien’s SilverHawk/TurboHawk plaque excision systems with Covidien’s SpiderFX embolic protection device for the treatment of moderately to severely calcified femoropopliteal lesions.

The DEFINITIVE Ca++ investigators concluded that the SilverHawk and TurboHawk atherectomy devices are safe and effective in the endovascular treatment of moderate to severely calcified lesions in the superficial femoral and/or popliteal arteries when used with the SpiderFX distal embolic protection device.

As summarized in Catheterization and Cardiovascular Interventions, the study enrolled 133 patients with 168 moderate to severely calcified lesions. Lesions were treated with directional atherectomy devices, coupled with distal embolic protection. 

The investigators found that the rate of 30-day freedom from major adverse events was 93.1%. Per angiographic core laboratory assessment, the primary effectiveness endpoint (≤ 50% residual diameter stenosis) was achieved in 92% (lower confidence bound of 87.6%) of lesions. By core lab analysis, these results did not achieve the success criteria (90%) for the primary effectiveness objective. Per site assessment, the objective was met with the endpoint being achieved in 97% (lower confidence bound 93.8%).

A mean residual diameter stenosis of 33.3% was achieved with the directional atherectomy device. This was further decreased to 24.1% with the use of adjunctive therapy. The proportion of asymptomatic subjects (Rutherford Clinical Category = 0) increased from 0% at baseline to 52.3% at the 30-day follow-up visit. In total, 88.5% of subjects experienced an improvement of one or more Rutherford categories, reported the DEFINITIVE Ca++ investigators in Catheterization and Cardiovascular Interventions.