Ask the doctor

How can you tell when a leaky mitral valve needs to be fixed?

Q. I am an 82-year-old man with borderline leakage in my mitral valve. Your article on mitral valve prolapse said, "The operation to repair or replace a leaky mitral valve is big enough that you don't want to undergo it unnecessarily, but important enough that you don't want to wait until symptoms develop." What symptoms or tests would help me and others recognize when it is time to consider having the valve fixed?

A. If you are having only a small or trivial amount of leakage of your mitral valve, the chance you will ever need surgery is vanishingly small. In fact, even normal mitral valves leak a little bit, and today's echocardiography equipment is so sensitive that it can detect this small amount of back flow. Mitral valve surgery is necessary only when the leakage (called mitral regurgitation) is substantial. This puts a burden on the heart because it has to "re-pump" the blood that spurts backward into the left atrium with each beat instead of flowing out into the aorta and on to the body. The strain of doing this extra work causes the heart to enlarge over time, which isn't good for the heart or health. It's best to repair or replace the mitral valve before the heart gets too big.