This is a catheter-based procedure to widen stiff or narrowed heart valves (stenotic heart valves). In some instances, it can be used in place of open-heart surgery to repair the problem. A catheter is inserted into an artery in the leg and guided to the heart, where it is positioned through the narrowed heart valve. The catheter has a small balloon on the tip, which is expanded to stretch the valve open, allowing the heart to bump more effectively.