Doppler echocardiographic evaluation of three models of bioprosthetic mitral valves

The aim of this study was to compare the Doppler echocardiographic characterists of three models of normally functioning bioprosthetic valves in the mitral position. Echocardiographic and Doppler studies were performed in 87 patients in whom Hancock (17), Carpentier-Edwards (32), and Liotta (38) models had been implanted in the mitral position. Two parameters of bioprosthetic transvalvular flow were assessed: maximum velocity of diastolic left ventrcular inflow (V(mas)), and pressure half-time (P 1/2 T). Hancock valves showed higher V(max) and P 1/2 T values than Carpentier-Edwards and Liotta valves. Moreover, only Hancock valves presented a significant difference in P 1/2 T values between larger and smaller valves (p < 0.001). Neither V(max) nor P 1/2 T were correlated to valve size or patient age; a significant inverse correlation was found between P 1/2 T and postoperative interval in Hancock (p < 0.05) and Carpentier-Edwards (p < 0.001), but not in Liotta valves. This study indicates that Hancock valve implantation in the mitral position is not preferable if a small bioprosthesis is need; Liotta and Carpentier-Edwards valves appear to perform better than Hancock in terms of pressure gradients, and Liotta valves seem to offer better long-term hemodynamic performance.