For the treatment of Aortic Valve Disease: Stenosis and Regurgitation
This information will help you understand the conditions that may affect the aortic valve and why surgical treatment may be needed to treat your condition.
Your aortic valve
What is the aortic valve?
There are four valves in your heart including the mitral, tricuspid, aortic and pulmonic valves.
The aortic valve is located between the left ventricle (lower heart pumping chamber) and the aorta, which is the largest artery in the body. Valves maintain one-way blood flow through the heart.
What is aortic valve disease?
Aortic valve disease occurs when the aortic valve does not work correctly. This can be caused by:
- Aortic valve stenosis: These stiff, fused, thickened, inflexible valve leaflets lead to the narrowing of the aortic valve, that limits the blood flow. Aortic valve stenosis progresses when calcium is deposited on the valve leaflets, further limiting their mobility. Stenosis can occur in patients with either a tricuspid (3 leaflets) or a bicuspid (2 leaflets) aortic valve.
- Aortic valve regurgitation (also called valvular insufficiency, incompetence or "leaky valve"): These valve leaflets do not close completely. Regurgitation causes the blood that is ejected by the heart to immediately flow back into the heart once the heart stops squeezing and relaxes. Regurgitation may occur because of floppy leaflets (prolapse), abnormal congenitally deformed valves (bicuspid or unicuspid), infection of the valve (endocarditis), inability of the leaflets to close tightly due to dilatation of the aorta (aneurysm), holes in the leaflets, or rheumatic valve disease.
What causes aortic valve disease?
The aortic valve may be abnormal at birth (typically a bicuspid congenital aortic valve) or become diseased over time, usually seen in older patients (acquired valve disease).
Congenital aortic valve disease
Patients with bicuspid aortic valves are born with them and are present in about 1 - 2 percent of the population.
Normal aortic valve
Bicuspid aortic valve
Instead of the normal three leaflets or cusps, the bicuspid aortic valve has only two. Without the third leaflet, the valve opening may not close completely and leak (regurgitant) or not open completely and become narrowed (stenotic) or leak.
In many cases, bicuspid aortic valves may function normally for several years without requiring treatment.
About 25 percent of patients with bicuspid aortic valves may have some enlargement of the aorta above the valve. If it is greatly dilated, the aorta is known as being aneurismal.
Acquired aortic valve disease
With acquired aortic valve conditions, changes occur in the structure of the valve. Acquired aortic valve conditions include:
- Infective endocarditis is a bacterial infection of the valve, which is caused when bacteria enter your blood stream from the site of a remote infection and attach to the surface of your heart valves. Dental cleaning or even minor infection, such as a tooth abscess, can cause severe bacterial endocarditis of the aortic valve.
- Rheumatic fever is usually caused by a bacterial throat infection, such as strep throat. The valve itself is not infected in rheumatic fever, but antibodies developed by the body to fight infection react with the heart valves, causing stiffening and fusion of the leaflets of the aortic valve.
- Aortic valve degeneration from wear and tear is another cause of acquired aortic valve disease. In many patients, the aortic valve leaflets degenerate and become calcified with time. This most frequently causes aortic stenosis, but may also cause aortic regurgitation. This is the most common cause of aortic stenosis in people over the age of 65.
- Other causes of aortic valve disease include: rheumatoid arthritis, chronic inflammatory diseases, lupus, syphilis, hypertension, aortic aneurysms, connective tissue diseases, and less commonly, tumors, some types of drugs and radiation for cancers or lymphoma.