The aortic valve guards the opening between the left ventricle and the aorta. The aortic valve opens as the left ventricle begins to pump, allowing blood to eject out of the heart and into the aorta. When the ventricle has finished beating, the aortic valve closes to keep blood from washing back into the left ventricle.
When you develop aortic regurgitation, your aortic valve fails to close completely, thus allowing blood to leak (or sometimes to rush) from the aorta back into the left ventricle. This "regurgitation" of blood causes the heart to work much much harder. This extra stress on the heart can lead to heart failure and other significant problems.
What Are The Causes Of Aortic Regurgitation?
- Endocarditis. Endocarditis (infection of the heart valves) can cause the aortic valve to deteriorate, producing regurgitation.
- Bicuspid aortic valve. Aortic regurgitation can be caused by a bicuspid valve, a congenital condition in which the aortic valve consists of only two "cusps" (i.e., flaps) instead of the normal three. Bicuspid aortic valves are especially prone to the formation of calcium deposits, which often produce aortic stenosis and can cause the valve to fail to close completely.
- Rheumatic heart disease. Fifty years ago, rheumatic heart disease was the leading cause of aortic regurgitation in the developed world. With the advent of antibiotics, rheumatic heart disease has become relatively uncommon.
- Congenital aortic regurgitation. Birth defects can produce aortic regurgitation, including Turner syndrome, tetralogy of Fallot, and truncus arteriosus.
- Dilation of the aortic root. The aortic root is the portion of the aorta immediately above the aortic valve. Several conditions can cause the aortic root to dilate or expand, and this can distort the aortic valve itself, causing regurgitation. Some of the causes of aortic root dilation include chronic high blood pressure, aortitis (inflammation of the aorta, which can be caused by diseases such as syphilis), chest injury, aortic dissection (sudden tearing of the wall of the aorta, caused by degenerative vascular disease), and Marfan syndrome.
What Problems Are Caused By Aortic Regurgitation?
In aortic regurgitation, the left ventricle has to work much harder in order to supply the body's tissues with a sufficient amount of blood. Specifically, with each heart beat, the ventricle must pump out all the blood that the body needs, plus the amount of blood that regurgitates back into the ventricle. This extra volume of blood causes the heart muscle to thicken (or "hypertrophy"), and causes the left ventricle to dilate.This extra stress on the left ventricle eventually can lead to heart failure, and to potentially deadly cardiac arrhythmias such as atrial fibrillation, or ventricular tachycardia and ventricular fibrillation.
Mild forms of aortic regurgitation usually produce no symptoms. However, if the regurgitation worsens, the ventricle becomes more stressed, and heart failure begins to develop. At this stage you may notice shortness of breath and difficulty exercising. These symptoms worsen as the valve problem worsens, and eventually can become quite severe.
While aortic regurgitation usually develops gradually - over a period of years - in some cases it can occur very suddenly. Acute aortic regurgitation is most commonly caused by endocarditis, a tear in the aorta, or chest trauma. Acute aortic regurgitation often produces sudden and severe heart failure, and can only be treated with emergency valve replacement surgery.
How Is Aortic Regurgitation Diagnosed?
If you think you might be experiencing aortic regurgitation, it's important to see your doctor right away for a proper diagnosis. Fortunately, aortic regurgitation can be diagnosed easily and painlessly.A physical examination will give your doctor several clues, most especially the characteristic heart murmur this valve problem produces. Your doctor may also suggest a chest x-ray or ECG. The diagnosis can be easily confirmed or ruled out with an echocardiogram.
Treating Aortic Regurgitation
While drug therapy can help to improve some of the symptoms of aortic regurgitation, eventually you may need surgery to replace or repair the damaged valve. Your doctor will explain all the options for treating aortic regurgitation.Sources:
Bonow, RO, Carabello, BA, Chatterjee, K, et al. 2008 Focused update incorporated into the ACC/AHA 2006 guidelines for the management of patients with valvular heart disease: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 1998 Guidelines for the Management of Patients With Valvular Heart Disease): endorsed by the Society of Cardiovascular Anesthesiologists, Society for Cardiovascular Angiography and Interventions, and Society of Thoracic Surgeons. Circulation 2008; 118:e523.
