Comparison of the closing kinematics of two designs of Mechanical Heart Valves (MHVs) against a Bioprosthetic Heart Valve

The Bileaflet Mechanical Heart Valves (BMHVs) are known to fully close later during the cardiac diastole compared to the natural/Bioprosthetic Heart Valve (BHVs), that fully close by the end of systole. Granted the widely reported relationship between the leaflet kinematics, hemodynamics and coagulant potential of prosthetic valves by the past research, new designs of MHVs are needed to replicate the physiological mechanics and function. This study compares the closure kinematics of a novel Trileaflet MHV (TMHV) against a BMHV and a BHV under similar numerical conditions. The flow solver employs the Curvilinear Immersed Boundary (CURVIB) method, strongly coupled to a Fluid-Structure Interaction (FSI) algorithm for the determination of the valves’ leaflet kinematics. The leaflets of the TMHV and BHV start to close during the forward deceleration phase of the cardiac cycle, and fully close by early diastole. Contrary to that, the BMHV leaflets do not begin their closing excursion until the onset of regurgitation. The hemodynamic reasons behind this behavior are explored in this study.