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A typical heart has two upper and two lower chambers. The upper chambers — the right and left atria — receive incoming blood. The lower chambers — the right and left ventricles — pump blood out of your heart. The heart valves, which keep blood flowing in the right direction, are gates at the chamber openings for the tricuspid and mitral valves and exits for the pulmonary and aortic valves. Aortic valve disease may be caused by a heart defect present at birth congenital heart defect.
Other causes of aortic valve disease later in life include:. To better understand the causes of aortic valve disease, it may be helpful to know how the heart valves typically work. In aortic valve stenosis, the aortic valve opening is narrowed top row. The narrowing requires increased pressure within the heart to pump blood across a smaller opening. Eventually this reduces the heart's ability to pump blood to the body. This is similar to attaching smaller and smaller nozzles to the end of a garden hose bottom row.
The narrowing from the nozzle slows the forward flow of water and results in pressure buildup within the garden hose. Each valve has flaps cusps or leaflets that open and close once during each heartbeat. Sometimes, a valve doesn't open or close properly. This can reduce or block blood flow through the heart to the rest of the body.
In aortic valve disease, the valve between the lower left heart chamber left ventricle and the body's main artery aorta doesn't work properly. The valve may be thickened and stiff stenosis or it may not close properly, causing blood to flow backward. Aortic valve disease care at Mayo Clinic. Mayo Clinic does not endorse companies or products. Advertising revenue supports our not-for-profit mission.
This content does not have an English version. This content does not have an Arabic version. Overview Aortic valve stenosis Open pop-up dialog box Close. Aortic valve stenosis Aortic valve stenosis causes a thickening and narrowing of the valve between the heart's main pumping chamber left ventricle and the body's main artery aorta. Aortic valve regurgitation Open pop-up dialog box Close.
The heart consists of four chambers, two atria upper chambers and two ventricles lower chambers. There is a valve through which blood passes before leaving each chamber of the heart. The valves prevent the backward flow of blood. These valves are actual flaps that are located on each end of the two ventricles lower chambers of the heart.
They act as one-way inlets of blood on one side of a ventricle and one-way outlets of blood on the other side of a ventricle. Normal valves have three flaps, except the mitral valve, which has two flaps. The four heart valves include the following:. As the heart muscle contracts and relaxes, the valves open and shut, letting blood flow into the ventricles and atria at alternate times. The following is a step-by-step illustration of how the valves function normally in the left ventricle:.
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