What Causes Aortic Valve Regurgitation?

Aortic valve regurgitation is also referred to as aortic insufficiency. The aortic valve consists of three flexible cup-shaped leaflets at the base of the aorta that are forced apart when the left ventricle contracts. The powerful contraction of the left ventricle pushes pressurized blood through the valve into aorta where it is then carried to the rest of the body. When the ventricle has emptied, the three leaflets snap back together in complete contact with each other.

In aortic insufficiency there is an abnormal regurgitation, or back flow, of blood from the aorta into the left ventricle. The regurgitation of aortic blood occurs while the left ventricle is in the process of relaxing and filling back up with oxygenated blood from the left atrium. Because of the regurgitated blood, the left ventricle is now forced to pump an extra large volume of blood. Over time the left ventricle will begin to fail and will cause congestive heart failure.

The causes of aortic regurgitation can fall under three main categories: (1) diseases of the aortic valve leaflets, (2) dilatation, which means thinning and expanding, of the aortic root and (3) proximal aortic root dissection, which describes separation of and bleeding into the layers of the aortic vessel wall. The aortic root is the section at and just above the base of the aorta where the aortic valve separates it from the left ventricle.

Causes of aortic valve regurgitation:

(1) Abnormalities of the valve leaflets from
-Rheumatic fever (autoimmune illness that can follow untreated Strep throat infection)
-Endocarditis (inflammation, and often infection, of the inner lining of the heart)
-Congenital bicuspid (rather than normal tricuspid) aortic valve

(2) Dilatation of the aortic root from
-Inflammation
-Connective tissue disease
-Marfan syndrome (a genetic disorder)
-Idiopathic, meaning unknown cause (though it does correlate with hypertension and increasing age)

(3) Aortic root dissection from
-syphilis (especially tertiary syphilis)
-Ehlers-Danlos syndrome (a genetic disorder)
-Turner's syndrome (a genetic disorder)
-Third trimester pregnancy
-Hypertension
-Cystic medial necrosis (often due to Marfan syndrome)

Aortic insufficiency will lead to eventual heart failure and, unfortunately, many of the causes of aortic regurgitation are genetic or congenital. Regurgitation from these causes is not preventable and there are no treatment options beyond surgery. However, several of the more common causes of aortic regurgitation, such as hypertension, syphilis, aortic dissection during pregnancy and rheumatic fever, are preventable by protecting your health and enlisting a knowledgeable physician to be part of your healthcare team.