Aortic valve regurgitation
Causes and risk factors
Rheumatic fever and syphilis used to be the most common causes of aortic regurgitation in North America, Australasia, and Western Europe, where both disorders are now rare because of the widespread use of antibiotics. In regions in which antibiotics are not widely used, aortic regurgitation due to rheumatic fever or syphilis is still common.
Aside from these infections, the most common causes of severe aortic regurgitation are weakening of the valve's usually tough, fibrous tissue due to myxomatous degeneration (a hereditary disorder in which the valve gradually becomes floppy); degeneration of the valve due to unknown factors; aortic aneurysms; and aortic dissection.
Common causes of mild aortic regurgitation are severe high blood pressure and a birth defect in which the aortic valve consists of two cusps (bicuspid valve) instead of the usual three (tricuspid valve). About 2% of boys and 1% of girls are born with this defect. Other causes of aortic regurgitation include bacterial infection of a heart valve (infective endocarditis) and injury.
Basically, any condition that damages a valve can cause or predispose regurgitation. Some of the more common ones include:
- Ankylosing spondylitis, a spinal disorder
- Aortic dissection and aortic aneurysm
- Congenital heart defects that are present at birth, such as unicuspid or bicuspid aortic valve
- High blood pressure
- Infective endocarditis, an infection in the valves or lining of the heart
- Marfan syndrome, an inherited disease of connective tissues
- Reiter syndrome, an arthritic disorder that affects adult males, which is now rare
- Rheumatic fever, a disease that can cause arthritis and heart problems
- Rheumatoid arthritis, which also causes joint pain and swelling
- Syphilis, especially congenital syphilis
- Systemic lupus erythematosus, an autoimmune disorder in which the person creates antibodies against his or her own tissues
- Ehlers - Danlos syndrome
- Pseudoxanthoma elasticum
- Deterioration of the valve with age
The ventricles pump blood in a forward direction from the heart to the aorta. Normally the aortic valve prevents backflow of blood to the heart when the heart relaxes after pumping. Back flow of the blood to the ventricle during relaxation leads to a subsequent increase in left ventricular volume. This leads to an increase in systolic blood pressure which is accompanied by reflex peripheral vessel dilatation which lowers the diastolic blood pressure resulting in a wide pulse pressure. The lowering of the diastolic blood pressure reduces flow of blood to the coronaries which relies on diastolic pressure. The resultant volume overload eventually leads to heart failure.
A leak may develop gradually (over months or years) or quickly (over hours or days). Aortic regurgitation may result when the aorta enlarges, often because of high blood pressure. When the aorta is enlarged, the valve may not close completely. As a result, blood leaks backward through the valve into the heart.
Aortic regurgitation may worsen if a person has a heart infection or aortic dissection. The function of the left heart chamber may deteriorate quickly within a few weeks or months. Chronic regurgitation usually progresses slowly. It can cause severe congestive heart failure, or CHF.
Are you a Doctor, Pharmacist, PA or a Nurse?
Join the Doctors Lounge online medical community
Editorial activities: Publish, peer review, edit online articles.
Ask a Doctor Teams: Respond to patient questions and discuss challenging presentations with other members.