advancing a valve catheter over a guidewire and through a patient's vasculature, the valve catheter having a shaft, a coupling element connected to a distal end portion of the shaft, and a plurality of flexible metal extension arms connected to and extending distally from the coupling element, wherein the extension arms are releasably attached to an expandable prosthetic heart valve having an expandable frame and a valvular structure, wherein the extension arms are shaped to flex outwardly during radial expansion of the prosthetic heart valve and to flex inwardly when the valve catheter is retracted into a passageway of a tubular sleeve;

positioning the prosthetic heart valve adjacent to a treatment site in the patient's heart while the prosthetic heart valve is in a collapsed state;

rotating a rotator knob on a handle assembly of the valve catheter for causing the valve catheter to slidably advance through the passageway of the tubular sleeve in a controlled manner;

exposing the prosthetic heart valve from a distal end of the tubular sleeve;

allowing the prosthetic heart valve to self-expand while the extension arms remain attached to the prosthetic heart valve;

actuating a release mechanism on the handle assembly for releasing the prosthetic heart valve from the extension arms; and

removing the valve catheter from the patient's vasculature;

wherein the prosthetic heart valve remains in the patient's heart with the expandable frame engaging surrounding tissue and the valvular structure replacing the function of the native heart valve;

wherein actuating the release mechanism causes a plurality of wires to retract for releasing the prosthetic valve from the extension arms;

wherein the extension arms are circumferentially spaced relative to each other, and wherein each wire is circumferentially aligned with a respective extension arm; and

wherein each wire extends alongside an outer surface of a respective extension arm.