A prosthetic heart valve for example a tricuspid valve may include a flexible membrane and a frame. The frame may be attached to the periphery of the tricuspid orifice. The diaphragm may be attached to the frame around a part of the perimeter of the orifice. Optionally the frame may be flexible. For example the frame may elastically flex between a substantially circular shape and/of an elliptical and/or crescent shape. Optionally there may not be a stiff cross piece crossing a central region of the orifice and connected on opposing sides of frame. In some embodiments the diaphragm may take a dome shape during systole.
