The application of biomimicry to a mechanical valve design for the abatement of flow instabilities

Abstract

Studies have suggested that the anterior leaflet of the native mitral valve aid in the formation of an asymmetric vortex ring similar to that seen in healthy left ventricles. The physiological vortex structure in the left ventricle is vital to the smooth redirection of the filling jet at the annulus to the aorta with minimal loss of energy. However, the implantation of artificial prostheses especially mechanical valves leads to the disruption of this flow field with an observed increase in turbulence levels. In light of this, we seek to investigate if this physiological left ventricular vortex can be replicated solely by the inclusion of an “anterior leaflet-like” feature within a mechanical valve design and its subsequent effects on downstream turbulence. In vitro experiments involving 2D3C particle image velocimetry was done on a newly designed mechanical valve consisting solely of a curved anterior leaflet and the results compared against that of the well-established Hancock II tissue bio-prosthesis, with the latter serving as a control. Our findings suggest that hemodynamic performance can be improved by solely mimicking the geometric feature of the anterior leaflet in a mechanical valve design, potentially resulting in lower thrombosis.