Three Dimensional Fluid Mechanics of the Sinus of Valsalva With a Bileaflet Mechanical Heart Valve

Fluid mechanics of the sinus of Valsalva is an underlying basis of aortic surgery. Bellhouse and Talbot first reported the closure mechanism of the human aortic valve in vitro, and found that a vortex motion in the sinus facilitates the initial closing response, thus minimizing the regurgitation [1]. Since their early study, a variety of researches have been conducted to gain systematic understanding of the flow in the sinus of Valsalva. Phase-contrast MRI technique in vivo and computational fluid dynamics in vitro are modern flow diagnostic tools, both of which potentially has a capability of characterizing the three-dimensional flow. However, the flow in reality is strongly affected by the opening and closing dynamics of the aortic valve, and vice versa. This fluid-structure coupling has yet to be understood systematically. This study aims to clarify the mechanism of the coupling in vitro with a bileaflet mechanical heart valve by means of 2D PIV and 3D Stereo PIV technique [2]. An emphasis is placed on the geometrical effect of the sinus of Valsalva, where three geometries, namely the Anatomical, Neosinus and Straight models, are compared on the flow dynamics and valve closing dynamics.