What is the Marfan Syndrome?

The Marfan syndrome is a heritable disorder of the connective tissue that affects many organ systems, including the skeleton, lungs, eyes, heart and blood vessels. The condition affects both men and women of any race or ethnic group. It is estimated that at least 200,000 people in the United States have the Marfan syndrome or a related connective tissue disorder.

What medical problems are associated with the 
Marfan syndrome?

•  The Cardiovascular System

The most serious problems associated with the Marfan syndrome involve the cardiovas­cular system. The two leaflets of the mitral valve may billow backwards when the heart contracts (mitral valve prolapse). This can lead to leakage of the mitral valve or irregular heart rhythm.

In addition, the aorta, the main artery carrying blood away from the heart, is generally wider and more fragile in patients with the Marfan syndrome. This widening is progressive and can cause leakage of the aortic valve or tears (dissection) in the aorta wall. When the aorta becomes greatly widened, or tears, surgical repair is necessary.

Skeletal manifestations common in people with the Marfan syndrome include curvature of the spine (scoliosis), abnormally shaped chest (pectus deformity), loose jointedness and dispropor-tionate growth usually, but not always, resulting in tall stature.

People with the Marfan syndrome are often near-sighted (myopic). In addition, about 50 percent have dislocation of the ocular lens.

How is Marfan syndrome diagnosed?

The Marfan syndrome is difficult to diagnose be­cause there is no specific laboratory test for the condition. In addition, characteristics of the disorder vary greatly among affected individuals. Most af­fected people do not have all of the possible signs and complications of the syndrome.

An accurate diagnosis of the Marfan syndrome can be assessed after a complete physical examination that focuses on the systems affected by the disorder. This includes:
•  Echocardiogram, a sound wave picture of the heart by a cardiologist.
• Slit-lamp eye examination by an ophthalmologist.
• Skeletal examination.
• Complete family history.
The recent identification of the chromosome, gene and component of connective tissue (fibrillin) in which the mutation for the Marfan syndrome is located offers great promise for the diagnosis of the condition. It is hoped that as a better understanding of fibrillin is gained, earlier and more accurate diagnosis of the Marfan syndrome will be possible.

How is the Marfan syndrome treated?

People affected by the Marfan syndrome should be treated by a physician familiar with the condition and how it affects all body systems. There is no cure for the disorder yet, but careful medical management can greatly improve the prognosis and lengthen the life span.

Every affected person should work closely with his/her physician(s) for their customized treatment plan. However, in general, treatment includes the following:

• Annual echocardiogram to monitor the size and function of the heart and aorta.
• Initial eye examination with a slit-lamp to detect lens dislocation, with periodic follow-up with an ophthalmologist.
• Careful monitoring of the skeletal system, especially during childhood and adolescence.
• Beta-blocker medications may be prescribed to lower blood pressure and, consequently, re­duce stress on the aorta.
• Antibiotics may be prescribed prior to dental or genito-urinary procedures to reduce the risk of infection in people who experience mitral valve prolapse.
• Lifestyle adaptations, such as the avoidance of strenuous exercise and contact sports, are often necessary to reduce the risk of injury to the aorta.

A single abnormal gene causes the Marfan syndrome. Usually, this gene is inherited from a parent who is also affected. Approximately one-quarter of the cases occur as a result of a spon­taneous mutation.

The Marfan syndrome is autosomal dominant, indicating that someone with the condition has a 50-50 chance that any offspring will inherit it.