A method of implanting a prosthetic mitral valve assembly using a transapical procedure is disclosed. An incision is formed in the chest in the apex of the patient's heart. A delivery catheter containing the prosthetic mitral valve assembly is advanced over a guidewire into the patient's heart. The prosthetic mitral valve assembly is deployed from the delivery catheter into the native mitral valve. The prosthetic mitral valve assembly comprises a stent having a lower portion for placement between the leaflets of a native mitral valve and an upper portion having a flared end for placement above the annulus. The prosthetic mitral valve includes a valve portion having leaflets formed of pericardial tissue. A plurality of upwardly bent prongs are provided along an outer surface of the stent for preventing upward migration of the prosthetic mitral valve assembly after deployment.