Abstract: A bileaflet heart valve comprising an annular base and pivoting leaflets. Each leaflet if "free-floating" within recesses without fixed rotational axis, to increase translational movement and redistribute stresses. Each recess fluidly communicates with a groove extending at least partially around the inner surface of the annular base and flow is directed through the recesses at different angles during antegrade circulation, retrograde circulation, and valve closure. A recess entrance angle to each of the recesses preferably being less than about 35.degree. and the pivoting mechanism within the recess including first and second fulcrum edges of each leaflet shiftably engaged with side surfaces of the respective recess. The leaflets have a beveled bottom surface having two separate planar surfaces which lie at an angle to one another. In preferred embodiments, a central region of each leaflet is spaced apart from the annular base when the leaflet is in a fully closed position to minimize cavitation.