Aortic regurgitation is reflux of blood from the aorta (the big vessel carrying blood out of the heart). The problem occurs when some of the blood pumped out falls back into the heart, because of an incompetent aortic valve which would normally stop this from happening.
The disease increases in incidence with increasing age and the vast majority of people over 80 years of age show evidence of regurgitation on testing with or without symptoms. The disease occurs more commonly in men, but the majority of patients with rheumatic AR are women.
The major predisposing factors are:
Rheumatic heart disease, syphilis;Damage to the cusps of the valve secondary to infective endocarditis;Any primary cause of aortic stenosis (progressive narrowing of the aortic valve) can lead to AR when the valve cusps become fixed and can not close adequately any longer.
Rarer associations include:
The reguritation of blood back into the left ventricle of the heart leads to dilatation of the ventricle. This reflects and attempt to maintain heart output by increasing the volume of blood being pumped out. This dilatation leads eventually leads to cardiac failure.
Left ventricular dilatation also decreases the amount of blood entering the heart causing angina and can also cause atrial fibrillation, infective endocarditis and mitral regurgitation. However, there are frequently no clinical symptoms until the onset of ventricular failure.
Clinical suspicion should dictate:
Compensation usually prevents the disease from becoming symptomatic for many years. As many as 85-95% of patients with mild-moderate regurgitation will live another 10 years. However after the onset of symptoms of heart failure, there is a fairly rapid deterioration within a couple of years.
General
Treatment of underlying causes- such as syphilis and infective endocarditis. Antibiotic prophylaxis agains development of infective endocarditis should also be used.
Specific
Surgical replacement of the valve should be undertaken but timing of the operation is important. Because a significantly enlarged heart will not recover completely, the operation should take place before the development of severe disease. Any heart failure should be treated with drug regimes.
Schlant RC, Alexander RW, Fuster V (eds). Hurst's The Heart (8th edition). New York, NY: McGraw-Hill; 1994. [Book]Kumar P, Clark M (eds). Clinical Medicine (4th edition). Edinburgh: WB Saunders Company; 1998. [Book]
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