A mechanical (or artificial) heart valve is a device that is used to replace one of a patient’s own damaged or diseased heart valves that cannot be repaired. A biological valve, from either an animal (xenograft) or a deceased human donor (allograft), may also be used to replace the patient’s original valve. In all, about 60,000 heart valves are replaced every year in the United States, according to the New England Journal of Medicine. Of these, the majority are mechanical valves. 

In most cases, the use of a mechanical heart valve can lengthen or even save a patient’s life. The valves are durable and can last 20 to 30 years or longer. However, there is a risk of complications, depending on the kind of valve used and its position in the heart. The most serious complications include blood clots that form on the surface of the valve, so patients will need to take anticoagulants for the rest of their lives. 

Patients are also urged to record the make, model and serial number of their mechanical heart valve in case there are any problems with it in the future.

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.

In most cases, replacing a diseased or damaged heart valve can lengthen or even save a life. Untreated, valvular heart disease can lead to heart failure and/or death. There are a number of rare but possible complications that could arise from the surgery needed to insert the mechanical heart valve.

Rarely, there may be a problem with the mechanical heart valve itself. Patients are encouraged to document the make, model and serial number of their mechanical heart valve in case any problems are announced in the future. For example, the Bjork-Shiley valve was used from 1979 to 1986, but has since been taken off the market due to safety concerns. Patients who believe they have these valves should consult a physician. Additionally, patients with mechanical heart valves will probably be monitored annually for signs of valve failure or complications.

The most significant ongoing risk for people with mechanical heart valves is the potential for blood clot formation. The ability of blood to clump together and form clots (coagulation) is a natural and necessary response to disease or injury. However, when clots form around a mechanical valve, patients are at an increased risk of a malfunction with the valve or a stroke. To reduce this risk, patients with mechanical valves will need to take anticoagulant medications for the rest of their lives. The dosage of these medications will be adjusted periodically to keep each patient’s risk as low as possible.

People with mechanical heart valves will need to see their physicians periodically for follow-up visits. These follow-up visits will usually include a painless echocardiogram, which can reveal any malfunction or leaking of the valve. Other tests, such as an electrocardiogram (EKG) or chest x-ray, may be performed.

People with mechanical heart valves face an increased risk of developing a potentially dangerous inflammation called bacterial endocarditis. This risk is increased when bacteria enter the bloodstream, such as during a dental, medical or surgical procedure. Once in the blood stream, the bacterial can infect the tissue surrounding the valve, or the valve itself. Therefore, people with mechanical heart valves are generally advised by their physicians to take antibiotics before any of these procedures to minimize their risk of bacterial endocarditis.

All people with mechanical heart valves will need to take medications called anticoagulants for the rest of their lives. These medications help prevent the body’s natural response of forming blood clots around a foreign object, such as a mechanical heart valve. Anticoagulants reduce the risk of blood clot formation, thus reducing the patient’s risk of valve malfunction, stroke and other potentially dangerous complications. To minimize the risk of bleeding during medical procedures such as surgery, a physician may recommend that anticoagulant therapy be suspended immediately before the surgery. This should only be done under the supervision of a physician.

Patients taking anticoagulants may need to undergo regular blood tests to monitor their medication dosage. These tests usually require the patient to visit a hospital, physician’s office or laboratory on a monthly, bimonthly or weekly basis. Since some prescription and over-the-counter medications can affect coagulation, patients should inform their physicians about any such products they are taking.

It is also wise for patients carry a form of identification (e.g., card, necklace, bracelet) stating that they have a mechanical heart valve, in case of emergency. 

Preparing questions in advance can help patients to have more meaningful discussions with their physicians regarding their conditions. Patients may wish to ask their doctor the following questions related to mechanical heart valves:

1. Is a mechanical heart valve a better option for me than a biological valve?
   
   
2. How often will I need to come in for evaluation following mechanical heart valve implantation?
   
   
3. How long will the mechanical heart valve last?
   
   
4. Are there any signs or symptoms I should be aware of that might indicate problems with the valve?
   
   
5. What type of mechanical heart valve will you use? Why do you think this type is most suitable?
   
   
6. What is the brand, model and serial number of the valve that was implanted in my heart?
   
   
7. Will I need to take any medications?
   
   
8. How often will I need blood tests to determine if my medication dosage is correct?
   
   
9. Are there any activities I would be unable to participate in with a mechanical heart valve?
   
   
10. Will a mechanical heart valve interfere with my ability to become pregnant?