Abstract 15470: Long Term Durability and Haemodynamic Performance of Freedom Solo Stentless Valve for Aortic Valve Replacement: A European, Multicenter Experience

Abstract

Introduction: Stentless aortic valves have been developed to overcome the obstructive limitations associated with stented bioprostheses. The Freedom Solo (FS) bovine pericardial valve is a third generation stentless bioprosthesis introduced in 2004 and FDA approved in 2014. Hypothesis: The aim of the current study is to report the multi-institutional experience by the three European centers that started implanting FS extensively as first from its introduction, providing the largest series with long-term follow-up. Methods: From 2004 to 2009, 478 patients (mean age 73±8.6 years, 199 [41.6%] females) underwent isolated (n=321) or combined (n=157) aortic valve replacement (AVR) with the FS. Follow-up, including clinical and strict echocardiographic evaluation, was 97.4% complete with an average follow-up time of 6.5±3.2 years (maximum 11.4 years) and cumulative follow up was 2612 patient/years. Primary end-point was freedom from structural valve deterioration (SVD) while secondary end-points were freedom from reoperation and overall survival. Results: Overall operative mortality was 2.9% (1.5% for isolated and 5.7% for combined AVR) and none was valve-related. Preoperative peak(mean) gradients were 76.1±30.6 mmHg (47.1±18.7 mmHg) decreased to 17.7±9.1 mmHg (9.9±5.4 mmHg), stable over the follow-up. Post-operative effective orifice area was 1.8±0.6 cm2, 1.98±0.5 cm2, 2.13±0.43 cm2 and 2.21±0.56 cm2 for valve size 21, 23, 25, and 27 respectively. There was no severe prostheses-patient mismatch (PPM) and moderate PPM occurred only in 1 patient(0.2%). Twenty-four patients (5.7%) underwent reoperation (16 surgical replacement, 8 TAVR) due to endocarditis(9), blunt trauma(1), and SVD(14). SVD was reported in 5 other patients alive at time of censor. Freedom from SVD and reoperation were 90.6% [88.2-93%] and 88.3% [85.8-90.8%] respectively at 10 years follow-up, while overall actuarial survival was 55.8% [52.5-59.1%]. Conclusions: The FS valve demonstrated excellent hemodynamic performance and long-term durability in this large, multi-institutional European experience. In particular, the FS proved to be a reliable bioprosthesis in aortic position given the low rate of structural valve deterioration along with a simple implantability.