St. Jude Medical cardiac valve prosthesis: in vitro studies.

The St. Jude Medical cardiac valve prosthesis is an all-pyrolitic carbon, bileaflet, low profile, central flow device. Prior to clinical use on intensive program of in vitro and in vivo testing was undertaken. Simulated radiographic studies determined that the tungsten impregnation needed to make the valve leaflets radiopaque was 0.013 inch. Steady-state flow and pulse duplicator studies demonstrated a high ratio of flow orifice to tissue anulus diameter with low transvalvular pressure gradients. Regurgitation was found to be acceptable. Flow visualization revealed central flow through all three flow orifices with minimal turbulence and vorticeal current formation. In vitro comparison with other available cardiac valve devices of various sizes demonstrated superior hemodynamic performance of the St. Jude Medical cardiac valve.