A heart valve prosthesis is provided having a self-expanding multi-level frame that supports a valve body comprising a skirt and plurality of coapting leaflets. The valve body comprises a skirt coupled to the leaflets at joints, where the joints are aligned with contours of the cell pattern of the frame. The lateral ends of the leaflets include enlarged regions that are folded to both form the commissural joints and fasten the commissural joints to the frame, where the commissures are configured to span a cell of frame. The skirt has end tabs that are folded over the ends of the proximal-most row of cells of frame to secure skirt to the frame so end tabs are directly supported by the last zig-zag row of cells of frame.