Heart Valve Disease

Heart valve disease occurs if one of more of your heart valves doesn't work properly. The heart consists of four chambers - two atria (upper chambers) and two ventricles (lower chambers). There is a valve through which blood passes before leaving each chamber of the heart. The valves prevent the backward flow of blood. (They act as one-way inlets of blood on one side of a ventricle and one-way outlets of blood on the other side of a ventricle.) The four heart valves include the following:

  • Mitral valve: located between the left atrium and the left ventricle
  • Aortic valve: located between the left ventricle and the aorta
  • Tricuspid valve: located between the right atrium and the right ventricle
  • Pulmonary valve: located between the right ventricle and the pulmonary artery

As the heart muscle contracts and relaxes, the valves open and close, letting blood flow into the ventricles and out to the body at alternate times. The following is an illustration of the valves of the heart:

Normal functionality in the left ventricle:

  • After the left ventricle relaxes, the aortic valve closes and the mitral valve opens to allow blood to flow from the left atrium into the left ventricle.
  • The left atrium contracts and more blood flow into the left ventricle.
  • When the left ventricle contracts, the mitral valve closes and the aortic valve opens so blood flows into the aorta and out into the systemic circulation to the rest of the body.

What is heart valve disease?

The two most common forms of heart valve disease are:

  • Stenosis (or narrowing of the valve): The valve(s) opening becomes narrowed, limiting the flow of blood out of the ventricles or atria. The heart is forced to pump blood with increased force in order to move blood through the narrowed or stiff (stenotic) valve(s).
  • Regurgitation (or leakage of the valve): The valve(s) does not close completely, causing the blood to flow backward through the valve. The heart is forced to pump more blood on the next beat, making it work harder.

Heart valves can develop both malfunctions at the same time (regurgitation and stenosis). Also, more than one heart valve can be affected at the same time. When heart valves fail to open and close properly, the implications for the heart can be serious, possibly hampering the heart's ability to pump blood adequately through the body. Heart valve problems are one cause of congestive heart failure.

Common Heart Valve Diseases

The mitral and aortic valves are most often affected by heart valve disease. Some of the more common heart valve diseases include:

This type of valve disease occurs primarily in the elderly and is characterized by a narrowing of the aortic valve opening, increasing resistance to blood flow from the left ventricle to the aorta.

Aortic Regurgitation

Aortic regurgitation results in blood leaking from the aortic valve into the left ventricle. This results in shortness of breath and ultimately enlargement and weakening of the left ventricle.

Mitral valve prolapse

This disease is characterized by the bulging of one or both of the mitral valve flaps during the contraction of the heart. One or both of the flaps may not close properly, allowing the blood to leak backward. This may result in a mitral regurgitation murmur.

Mitral valve regurgitation is an incompetent or leaky valve. This results in fatigue or shortness of breath.

Mitral valve stenosis

Often caused by a past history of rheumatic fever, this condition is characterized by a narrowing of the mitral valve opening, increasing resistance to blood flow from the left atrium to the left ventricle.

Tricuspid regurgitation

This disorder is when the tricuspid valve does not close properly leading to leakage of blood. The most common cause is pulmonary hypertension or left side congestive heart failure. This results in fatigue, swelling of abdomen, liver and legs.

Pulmonary stenosis

This condition is characterized by a pulmonary valve that does not open sufficiently, causing the right ventricle to pump harder and enlarge.

Bicuspid Aortic Valve

This congenital birth defect is characterized by an aortic valve that has only two flaps (a normal aortic valve has three flaps). This can lead to aortic valve stenosis or regurgitation. Additionally, it can be associated with aortic aneurysm. Symptoms usually do not develop during childhood, but are often detected during the adult years.