Prospective multicenter evaluation of the direct flow medical transcatheter aortic valve

Objectives: The study sought a prospective multicenter nonrandomized evaluation of the Direct Flow Medical (DFM) system for the treatment of severe aortic stenosis. Background: The DFM transcatheter aortic valve system is a nonmetallic design with a pressurized support structure that allows precise positioning, retrieval, and assessment of valve performance prior to permanent implantation. Methods: One hundred high surgical risk patients with severe aortic stenosis were evaluated for the primary endpoint. There were 75 patients in the group evaluable for the secondary endpoints and 25 in the pre-specified roll-in training phase. Echocardiographic and angiographic data were evaluated by an independent core laboratory and adverse events adjudicated by clinical event committee and classified according to Valve Academic Research Consortium (VARC) criteria. Results: There was 99% freedom from all cause mortality at 30 days (primary endpoint). VARC criteria defined 30 day combined freedom from patient safety event rate was 91% and overall device success was 93%. The post-implantation echocardiography results demonstrated mild or no aortic regurgitation in 99% (73 of 74) with a mean gradient of 12.6 ± 7.1 mm Hg (n = 72) and effective orifice area of 1.50 ± 0.56 cm² and New York Heart Association functional class was I or II in 92% of cases. Conclusions: The present study demonstrates the safety and efficacy of the DFM system in surgical high risk patients with severe aortic stenosis and complex anatomy aortic regurgitation was less than moderate in 99% of patients.