Aortic regurgitation is due to deterioration of the aortic valve and the surrounding aortic root (base of the aorta—the blood vessel transporting blood from the heart to the rest of the body).
The deterioration sometimes occurs in a person with a bicuspid aortic valve Bicuspid Aortic Valve A bicuspid aortic valve is an aortic valve that has two cusps (leaflets) instead of the normal three. (See also Overview of Heart Defects.) The aortic valve is the valve that opens with each... read more but may also result from a bacterial infection of the valve or rheumatic fever Rheumatic Fever Rheumatic fever is inflammation of the joints, heart, skin, and nervous system, resulting from a complication of untreated streptococcal infection of the throat. This condition is a reaction... read more
.Aortic regurgitation causes no symptoms unless heart failure develops.
Doctors make the diagnosis because of symptoms and physical examination findings, and they use echocardiography to confirm the diagnosis and measure its severity.
The damaged heart valve must be monitored periodically so that it can be replaced or repaired surgically once the leakage becomes significant and the heart starts to fail.
(See also Overview of Heart Valve Disorders Overview of Heart Valve Disorders Heart valves regulate the flow of blood through the heart's four chambers—two small, round upper chambers (atria) and two larger, cone-shaped lower chambers (ventricles). Each ventricle has... read more 
and the video .)
The aortic valve is in the opening between the left ventricle and the ascending aorta (the large artery leading from the heart). The aortic valve opens as the left ventricle contracts to pump blood into the aorta. When the aortic valve does not close completely, blood leaks backward from the aorta into the left ventricle as the left ventricle relaxes to fill with blood from the left atrium. The backward leakage of blood, termed regurgitation, increases the volume and pressure of blood in the left ventricle. As a result, the amount of work the heart has to do increases. To compensate, the muscular walls of the ventricles thicken (hypertrophy), and the chambers of the ventricles enlarge (dilate). Eventually, despite this compensation, the heart may be unable to meet the body's need for blood, leading to heart failure Heart Failure (HF) Heart failure is a disorder in which the heart is unable to keep up with the demands of the body, leading to reduced blood flow, back-up (congestion) of blood in the veins and lungs, and/or... read more 
, with fluid accumulation in the lungs.
Causes of Aortic Regurgitation
Aortic valve regurgitation may develop suddenly (acute) or gradually (chronic).
The most common causes of acute aortic regurgitation are
The most common causes of chronic aortic regurgitation are
Spontaneous weakening of the valve or the ascending aorta (particularly with a birth defect in which the aortic valve is bicuspid Bicuspid Aortic Valve A bicuspid aortic valve is an aortic valve that has two cusps (leaflets) instead of the normal three. (See also Overview of Heart Defects.) The aortic valve is the valve that opens with each... read more with only two, instead of three, cusps)
Rheumatic fever and syphilis Syphilis Syphilis is a sexually transmitted infection caused by the bacteria Treponema pallidum. It can occur in three stages of symptoms, separated by periods of apparent good health. Syphilis... read more 
used to be the most common causes of aortic regurgitation in North America and Western Europe, where both disorders are now rare because of the widespread use of antibiotics. In regions where antibiotics are not widely used, aortic regurgitation due to rheumatic fever or syphilis is still common.
About 1% of babies have a bicuspid aortic valve, but it commonly does not cause problems until adulthood.
Symptoms of Aortic Regurgitation
Mild aortic regurgitation causes no symptom other than a characteristic heart murmur that can be heard with a stethoscope each time the left ventricle relaxes. People with severe regurgitation may develop symptoms when heart failure results.
Heart failure Heart Failure (HF) Heart failure is a disorder in which the heart is unable to keep up with the demands of the body, leading to reduced blood flow, back-up (congestion) of blood in the veins and lungs, and/or... read more causes shortness of breath during exertion. Lying flat, especially at night, makes breathing difficult. Sitting up allows backed-up fluid to drain out of the upper part of the lungs, restoring normal breathing. About 5% of people with aortic regurgitation have chest pain due to an inadequate blood supply to the heart muscle (angina Angina Angina is temporary chest pain or a sensation of pressure that occurs while the heart muscle is not receiving enough oxygen. A person with angina usually has discomfort or pressure beneath the... read more ), especially at night.
The pulse, sometimes called a collapsing pulse, is momentarily strong, then disappears quickly because the blood leaks backward through the aortic valve into the heart, causing blood pressure to decrease sharply.
Diagnosis of Aortic Regurgitation
Physical examination
Echocardiography
The diagnosis is based on the results of a physical examination (such as the collapsing pulse and characteristic heart murmur) and confirmed by echocardiography Echocardiography and Other Ultrasound Procedures Ultrasonography uses high-frequency (ultrasound) waves bounced off internal structures to produce a moving image. It uses no x-rays. Ultrasonography of the heart (echocardiography) is one of... read more 
. Echocardiography also shows the severity of the regurgitation and whether the heart muscle has been affected. If echocardiography results suggest the aorta is widened, doctors often do computed tomography Computed Tomography (CT) of the Heart Computed tomography (CT) may be used to detect structural abnormalities of the heart, the sac that envelops the heart (pericardium), major blood vessels, lungs, and supporting structures in... read more (CT) or magnetic resonance imaging Magnetic Resonance Imaging (MRI) of the Heart With magnetic resonance imaging (MRI), a powerful magnetic field and radio waves are used to produce detailed images of the heart and chest. This expensive and sophisticated procedure is used... read more (MRI) to detect aortic dissection.
Chest x-ray and electrocardiography Electrocardiography Electrocardiography (ECG) is a quick, simple, painless procedure in which the heart’s electrical impulses are amplified and recorded. This record, the electrocardiogram (also known as an ECG)... read more 
(ECG) usually show signs of an enlarged heart. Coronary angiography Coronary angiography Cardiac catheterization and coronary angiography are minimally invasive methods of studying the heart and the blood vessels that supply the heart (coronary arteries) without doing surgery. These... read more 
is done before surgery because about 20% of people with severe aortic regurgitation also have coronary artery disease Overview of Coronary Artery Disease (CAD) Coronary artery disease is a condition in which the blood supply to the heart muscle is partially or completely blocked. The heart muscle needs a constant supply of oxygen-rich blood. The coronary... read more 
. First-degree relatives (that is, parents, siblings, or children) of people with a bicuspid valve should also be screened because 20 to 30% will be similarly affected.
Treatment of Aortic Regurgitation
Valve repair or replacement
Drug treatment is not especially effective in slowing the progression of heart failure and does not eliminate the need for timely valve repair or replacement.
Echocardiography is done periodically to determine how rapidly the left ventricle is enlarging, which will help doctors determine when surgery should be done. The damaged valve should be surgically repaired or replaced with an artificial valve before the left ventricle becomes irreversibly damaged.
People who have had a valve replacement are given antibiotics before surgical, dental, or medical procedures (see table Examples of Procedures That Require Preventive Antibiotics Examples of Procedures That Require Preventive Antibiotics in the United States* 
) to reduce the risk of infection of the heart valve.
More Information
The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.
American Heart Association: Heart Valve Disease: Provides comprehensive information on diagnosis and treatment of diseases of the heart valves
