Q: My mother is undergoing surgery to have a mechanical heart valve. What is the lifespan of a mechanical heart valve?

A: Mechanical heart valves are made of a substance called pyrolytic carbon, which is similar to industrial grade diamond. It is very hard and wears very little.

These valves are tested for durability by making the valve open and close over and over again like in the heart (about the same number of heart beats if you lived 100 years!) and show almost no wear.

Although mechanical failure is extremely unlikely, there are other problems like infection that could require further surgery. This is also very unlikely if the patient follows the American Heart Association's recommendations.