A Fluid Structure Interaction Model of Bileaflet and Monoleaflet Mechanical Heart Valve Flow Dynamics

The goal of the study was to develop a 3D numerical model to evaluate the opening and closing behavior of a monoleaflet and a bileaflet mechanical heart valve in a left‐ventricle simulating flow chamber. A diaphragm located at the bottom of the chamber drove the flow in the chamber to circulate through two mechanical heart valves on each side of the chamber. 3D Fluid Structure Interaction (FSI) approaches (ANSYS) were employed to describe the movement of the diaphragm and the valve leaflets. The opening angle of the bileafelt heart valve was set at 85°, and that of the monoleaflet heart valve varied between 45° and 85°. Hemodynamic performance of these valves were evaluated by maximum flow velocity through the valve, average pressure gradient across the valve, valve opening and closing time, and effective orifice area. The results demonstrated that the 3D numerical model was able to accurately simulate the opening and closing of these heart valves. The hemodynamic performance of the monoleaflet heart valve was heavily dependent on the opening angle. An opening angle between 75° to 80° provided the best hemodynamic performance of the monoleaflet heart valve. At this angle, the flow conditions around the monoleaflet valve was slightly better than that around the bileaflet valve, with a large effective orifice area, lower maximum flow velocity, and lower average transvalvular pressure. This work is supported by NSF‐DMR0907291.