St. Jude SPV versus Medtronic Freestyle: A single institution comparison of two stentless aortic valves

Background: Improved hemodynamics with the SPV and Freestyle bioprostheses compared to stented valves have been reported. It has been suggested that t here is more aortic insufficiency (Al) with the Freestyle than with the SPV valve. This study was designed to assess the hemodynamic performance of th ese two valves implanted at a single institution with all echocardiograms r eviewed by one echocardiographer. Methods: From 1993 to 1997 112 patients u nderwent aortic valve replacement with stentless aortic valves (69 SPV, 43 Freestyle). There were no major preoperative differences in patient age, ge nder, NYHA class, or ejection fraction between groups. Echocardiographic as sessment was obtained at discharge, 3 to 6 months following surgery, and ye arly thereafter. Results: Mean follow-up was 15.9 months for the SPV and 28 .6 months for the Freestyle. Both valves have excellent valve areas and low transvalvar mean gradients. There is a trend for more Al in the SPV group. At 1 year, 1+ or greater Al was present in 11 of 42 SPV patients compared to 2 of 34 Freestyle patients (p = 0.030). Al has tended to remain stable o ver time, has not progressed, and is not clinically evident. Discussion: Di fferences in the previously reported incidence of aortic insufficiency with these valves may have more to do with the method of reporting Al than its actual frequency. Within our institution, there has been slightly more mild Al with the SPV valve than with Freestyle. Long-term follow-up of these va lves is needed to determine if the Al progresses or becomes clinically impo rtant. To date there is no such trend with either valve.