Abstract: An improved prosthetic mitral valve is provided having advantageous hemodynamic performance, nonthrombogenicity, and durability. The valve includes a valve body having an inflow annulus and an outflow annulus. Commissural attachment locations are disposed adjacent the outflow annulus. An anterior leaflet and a posterior leaflet of the valve are shaped differently from one another. The inflow annulus preferably is scalloped so as to have a saddle-shaped periphery having a pair of relatively high portions separated by a pair of relatively low portions. The anterior high portion preferably is vertically higher than the posterior high portion.