Monday, July 28, 2014

Aortic Valve Disease

Definition

Aortic Valve Disease entails damage to, and dysfunction of, the aortic valve, one of the four valves in the heart.

Description

The most common valvular problem in old age is aortic valve disease.

The aortic valve is one of four valves that control the flow of blood into and out of the heart. In particular, the aortic valve controls the flow of oxygenated blood pumped out of the heart from the left ventricle into the aorta, the main artery leading to the rest of the body.

If the valve is abnormally narrow (aortic stenosis), the heart must work harder for a sufficient amount of blood to be pumped with each beat.

On the other hand, if the valve does not close properly, it may cause aortic regurgitation because some of the blood being pumped out into the aorta regurgitates, or leaks backward, into the left ventricle with each beat.

In either case, the work of the ventricle increases. As a result, its muscular wall thickens (a condition known as hypertrophy) and the left ventricle may become larger (dilate).

Aortic stenosis refers to the process of thickening and stiffening in the valve. The valve itself, however, may continue to function adequately for years, with nothing more than a heart murmur heard by the physician on examination with a stethoscope. The murmur is caused by turbulence of blood passing through the valve.

In aortic stenosis, the aortic valve becomes narrowed and blocked by hard, calcified deposits, or in some people, from rheumatic fever years earlier. This condition is present in about 4 percent of all elderly people. Severe aortic valve stenosis can cause fainting (because of impaired blood flow to the brain across the narrowed valve); heart failure and shortness of breath (when the heart's muscle becomes unable to pump blood in a forward direction through narrow opening); and chest pain (because of increased work and a lack of sufficient oxygen reaching heart muscles).

Aortic regurgitation is usually asymptomatic until middle age. Patients may present with heart failure or chest pain. Some causes of aortic regurgitation include congenitally bicuspid (only two cusps instead of three) valves, infective endocarditis, and high blood pressure.

Causes

Aortic valve disease can be congenital, result from infection, occur as a result of rheumatic heart disease, result from the processes of aging, or be of unknown origin.

Symptoms

An aortic valve disorder usually does not cause any symptoms in its early stages. As the problem progresses, it may produce shortness of breath, angina (chest pain), light-headedness, dizziness, and even fainting, especially upon exertion. Many elderly people with aortic stenosis remain free of symptoms.

Diagnosis

Most cases of aortic valve disease can be diagnosed by a physical examination, during which a characteristic heart murmur may be detected. A chest X-ray, an electrocardiogram (EKG, to determine whether the heart is enlarged), and an echocardiogram (ultrasound study of heart muscle and valves) also may be done. If enough physical symptoms are present, cardiac catheterization may be necessary to better evaluate the valve and heart function.

Treatment

Your physician will recommend medications to control blood pressure and will discuss with you the range of blood pressure that will be beneficial for your specific condition.

Limitations on strenuous activity (especially lifting heavy objects) are recommended, particularly for those with aortic stenosis.

If symptoms are present or there is severe ventricular dysfunction with either stenosis or regurgitation, surgery to repair, or more likely replace, the defective valve often will be recommended.

Questions

Can aortic valve disease be detected early enough to eliminate the need for surgery?

What is the difference between a heart attack and aortic valve disease?

What is cardiac catheterization?

Are there any medications that will help manage this condition?

If surgery is recommended, what type of valve will you be using to replace the defective valve?