A method for implanting a heart valve into a patient's heart can include securing the heart valve prosthesis to a distal portion of an implanter apparatus. An opening is created in muscle tissue of the patient's heart, through which a length of the barrel is inserted such that an end of the barrel is advanced toward the implantation site. The heart valve prosthesis is advanced through the barrel to the implantation site. The heart valve prosthesis is positioned at the desired implantation site. The heart valve prosthesis can be expanded at the desired implantation site to anchor the prosthesis into adjacent tissue.
