What is Aortic Stenosis

What is Aortic Stenosis?


The aorta is the main artery leaving the heart. The normal aortic valve consists of three leaflets. There are two ways that the aortic valve can malfunction:

  • A stenotic, or narrowed, aortic valve does not fully open as a result of disease affecting the ability of the valve leaflets to open. This creates an obstruction to the outflow of blood from the left ventricle.
  • An insufficient aortic valve leaks and allows backflow of blood from the aorta into the left ventricle during diastole.

Asymptomatic patients with aortic stenosis or aortic insufficiency have a good prognosis. Once symptoms develop, the prognosis becomes poor and surgery is usually necessary to repair or replace the valve. Aortic stenosis is the most common reason patients undergo heart valve surgery.


The two most common causes of aortic stenosis in North America are degenerative calcification of the aortic valve and a congenital bicuspid aortic valve. Degenerative calcific aortic stenosis is a disease of aging and will become increasingly common as the United States population ages. The presence of obstruction to ventricular outflow causes hypertrophy, or enlargement, of the left ventricular myocardium (heart muscle), which compensates for the outflow obstruction.

Risk Factors

Aortic stenosis may be present from birth (congenital), or it may develop later in life (acquired). Aortic stenosis occurs more often in men than in women, and is common among individuals in the elderly population due to calcium deposits that form around the aortic valve over time.

Individuals who have been treated with radiation therapy to the chest region or have taken specific medications may also be at risk for developing aortic stenosis.


People with aortic stenosis may not develop symptoms until late in the course of the disease. The three classic symptoms of aortic stenosis are:

  • Shortness of breath (dyspnea)
  • Chest pain (angina)
  • Fainting (syncope)

If an individual experiences the above symptoms, he or she should seek prompt evaluation by a physician. Surgery is highly effective at relieving outflow tract obstruction, preventing sudden death, improving left ventricular function and alleviating symptoms.


If there are no symptoms or symptoms are mild, individuals may only need to be monitored by a health care provider. Once symptoms develop or worsen, surgery to repair or replace the valve is necessary. Aortic stenosis is the most common reason for patients to undergo open-heart surgery for valvular heart disease. However, doctors at the University of Maryland Medical Center have pioneered a minimally invasive alternative procedure to treat aortic stenosis. More than 70,000 patients in the United States undergo replacement of the aortic valve every year.

This page was last updated: August 19, 2014

Average rating (5)