Blood is pumped through your heart in only one direction. Heart valves play a key role in this one-way blood flow, opening and closing with each heartbeat. Pressure changes on either side of the valves cause them to open their flap-like "doors" (called cusps or leaflets) at just the right time, then close tightly to prevent a backflow of blood.
There are 4 valves in the heart:
- Tricuspid valve
- Pulmonary valve
- Mitral valve
- Aortic valve
In the United States, surgeons perform about 99,000 heart valve operations each year. Nearly all of these operations are done to repair or replace the mitral or aortic valves. These valves are on the left side of the heart, which works harder than the right. They control the flow of oxygen-rich blood from the lungs to the rest of the body.
Severe valve damage means that the valve will need to be replaced. Valve replacement is most often used to treat aortic valves and severely damaged mitral valves. It is also used to treat any valve disease that is life-threatening. Sometimes, more than one valve may be damaged in the heart, so patients may need more than one repair or replacement.
There are 2 kinds of valves used for valve replacement:
- Mechanical valves, which are usually made from materials such as plastic, carbon or metal. Mechanical valves are strong, and they last a long time. Because blood tends to stick to mechanical valves and create blood clots, patients with these valves will need to take blood-thinning medicines (called anticoagulants) for the rest of their lives.
- Biological valves, which are made from animal tissue (called a xenograft) or taken from the human tissue of a donated heart (called an allograft or homograft). Sometimes, a patient's own tissue can be used for valve replacement (called an autograft). Patients with biological valves usually do not need to take blood-thinning medicines. These valves are not as strong as mechanical valves, though, and they may need to be replaced every 10 years or so. Biological valves break down even faster in children and young adults, so these valves are used most often in elderly patients.
You and your doctor will decide which type of valve is best for you.
During valve repair or replacement surgery, the breastbone is divided, the heart is stopped, and blood is sent through a heart-lung machine. Because the heart or the aorta must be opened, heart valve surgery is open heart surgery.
Life After Valve Replacement
Most valve repair and replacement operations are successful. In some rare cases, a valve repair may fail and another operation may be needed.
Patients with a biological valve may need to have the valve replaced in 10 to 15 years. Mechanical valves may also fail, so patients should alert their doctor if they are having any symptoms of valve failure.
Patients with a mechanical valve will need to take a blood-thinning medicine for the rest of their lives. Because these medicines increase the risk of bleeding within the body, you should always wear a medical alert bracelet and tell your doctor or dentist that you are taking a blood-thinning medicine.
Even if you are not taking a blood-thinning medicine, you must always tell your doctor and dentist that you have had valve surgery. If you are having a surgical or dental procedure, you should take an antibiotic before the procedure. Bacteria can enter the bloodstream during these procedures. If bacteria get into a repaired or artificial valve, it can lead to a serious condition called bacterial endocarditis. Antibiotics can prevent bacterial endocarditis.
Patients with mechanical valves say they sometimes hear a quiet clicking sound in their chest. This is just the sound of the new valve opening and closing, and it is nothing to be worried about. In fact, it is a sign that the new valve is working the way it should.