A mechanical (or artificial) heart valve is a device that is used to replace a damaged or diseased heart valve that cannot be repaired. The mechanical heart valve is inserted into the patient’s heart as part of an open-heart surgery called heart valve replacement. Of the 60,000 heart valves replaced every year in the United States, according to the New England Journal of Medicine, the majority are mechanical. The rest are biological valves from an animal (xenograft) or a deceased human donor (allograft).

Any of a patient’s four heart valves (aortic valve, mitral valve, pulmonic valve or tricuspid valve) may be replaced with a mechanical heart valve. Mechanical heart valves tend to last about 20 or 30 years or even more, significantly longer than biological valves, which usually need to be replaced every 10 to 15 years. 

A mechanical heart valve works in the same manner as a natural heart valve, opening and closing with each heartbeat. They are usually made from plastics and metals and there are several types available. One type of mechanical heart valve involves a silicon ball that moves inside a metal cage to open and close the valve. Other types may include tilting disc designs or bileaflet valves.