A prosthetic valve delivery system for percutaneously delivering and deploying a prosthetic valve within an existing valve is disclosed. The delivery system includes a stented prosthetic valve having a balloon-expandable stent portion with a prosthetic valve disposed therein and at least one self-expanding stent portion. The delivery system further includes a dual balloon catheter having a first balloon on which the stented prosthetic valve is disposed during delivery and a second balloon. Upon delivery within the existing valve, the self-expanding stent portion contacts the existing valve and the first balloon expands the balloon-expandable stent portion to a first diameter such that the stented prosthetic valve is in a first stage deployment configuration. The second balloon then expands the balloon-expandable stent portion to a second diameter, greater than the first diameter, such that the stented prosthetic valve is in a second stage deployment configuration being fully deployed within the existing valve.