A valve implant or prosthesis includes a skirt or prosthetic valve leaflet configured to cover one of the leaflets of the valve to be repaired in a patient's heart. In one embodiment, a heart valve prosthesis includes a curved member and a skirt. The curved member can have first and second ends and be adapted to form a partial ring along a portion of one of the valve annulae in the patient's heart. Alternatively, the curved member can form a full ring that is adapted to extend along the entire valve annulus. The skirt extends along the curved member and depends therefrom. This prosthesis is especially useful in treating mitral valve insufficiency. In this case, the skirt can be configured so that when the prosthesis is secured to the mitral valve along the mitral valve annulus, the skirt covers the posterior leaflet and the opposed edges of the skirt and the anterior leaflet coapt. In addition, when the curved member is secured to the posterior portion of the mitral valve annulus, further annulus dilation can be minimized or eliminated. Implant delivery apparatus is provided for rapid implant delivery and securement to the valve.