LDA Study of the Flow Associated With the Design Differences and Orientations of the Bileaflet Mechanical Prostheses

Four typical mechanical bileaflet heart valves (St. Jude Medical, Advancing The Standard, Carbomedics, and Jyros valves) have been tested in the mitral position under pulsatile flow conditions. Measurements of velocity and turbulent stresses were conducted at five downstream locations using a sophisticated cardiac simulator in conjunction with a highly sensitive two-component LDA. Comparison of these flow fields associated with the opening and subsequent accelerating phase of the flow revealed similarity and dissimilarity of the flow field associated with the different valve designs and helped established visualizing the effect of the valve designs and orientations on the flow.