Development of built-in polyurethane (PU) valves for ventricular assist device

Abstract

L and S type two aluminium molds, whose sizes matched 25 and 21 ABP of the Björk-Shiley (BS) valves, respectively, were developed and used to fabricate one-piece conduit type PU valves. In-vitro test data of pump flow, pressure gradient and effective orifice area for L type valves suggested that leaflet thicknesses of 0.20mm and 0.32mm in the inlet and outlet, respectively, result i n the optimal valve performance. As, for the S type valves, the valve with 0.40mm leaflet thickness lead to undesirable pump performance, while usage of 0.26mm valves gave comparable performance as that of the BS valves.