Prospective randomised evaluation of stentless versus stented aortic bioprostheses at five years

Objective: Randomized trials comparing stentless to stented bioprostheses are rare. The aim of this study was midterm evaluation of these bioprostheses, with regards to clinical outcome and hemodynamic performance. Methods: Between September 1999 and January 2001, forty patients with aortic stenoses, over the age of 75 years, were randomly assigned to receive either the stented Perimount (n=20) or the stentless Prima Plus (n=20) bioprosthesis. Clinical outcomes, left ventricular mass regression, effective orifice area, ejection fraction and mean gradients were evaluated at discharge, six months, one year and five years after surgery. Results: At five years, there were 5/20 (25%) deaths in the stentless group and 6/20 (30%) deaths in the stented group (all were not-valve-related). There was one case of endocarditis in each group, early postoperatively. Overall, a significant decrease in left ventricular mass was found five years postoperatively. However, there was no significant difference in the rate and completeness of LV-mass regression between the groups (LV mass index 114±34.1 versus 120±27.2). Furthermore, hemodynamic performance of the valves (mean gradient of 9.9±4.8mmHg versus 10.2±4.2mmHg) did not differ significantly between the groups. Conclusion: At five years, stentless valves were not superior to the stented valves, with regards to hemodynamic performance, regression of left ventricular mass and clinical outcome.