A method of delivery a prosthetic heart valve includes inserting a delivery apparatus and a prosthetic heart valve into a patient's vasculature. The delivery apparatus includes a steerable guide catheter, a balloon catheter, and a flex indicator. The balloon catheter extends coaxially through the guide catheter, the prosthetic heart valve is mounted on a distal end portion of the balloon catheter, and the flex indicator is movably coupled to a handle of the guide catheter. The method further includes adjusting flexion of a steerable section of the guide catheter to position the prosthetic heart valve. The flex indicator moves relative to the handle of the guide catheter as the flexion of the steerable section is adjusted, and the handle comprises one or more visual indicators adjacent the flex indicator to provide visual indication of an amount of flexion of the steerable section of the guide catheter.