Marfan Syndrome

Marfan syndrome is a rare disorder that weakens the connective tissue in the body. Connective tissue holds together many structures in the body, such as tendons, ligaments, cartilage, blood vessels, heart valves, lungs, eyes, and other organ systems. Because the connective tissue is weaker in Marfan patients, it affects how the heart and blood vessels, eyes, and skeleton are formed and how they work. Approximately 200,000 people in the United States have Marfan syndrome, and it can occur in men or women of any race or ethnic group. Many affected individuals are young adults, adolescents, or children.

What Causes Marfan Syndrome?

Marfan syndrome is inherited (75%) or results from a genetic defect (25%). Children have a 50% chance of inheriting the gene from a parent. About 50,000 Americans are diagnosed with the condition each year. Marfan syndrome can affect both men and women. Due to its genetic component, patients with Marfan syndrome should talk to their doctor and a genetic counselor before having children.

What are the Risks to the Heart and Blood Vessels?

The defect in the gene that causes Marfan syndrome controls the production of a special protein found in connective tissue. This protein is called fibrillin. Without enough fibrillin, the walls of the major arteries are weakened. If the aorta is affected, it dilates and weakens. A weakened aorta can develop an aneurysm or a dissection.

A stretched and weakened aorta also affects the aortic valve. In some patients, blood leaks backward through the valve (regurgitation). This type of heart valve disease forces the heart to work harder so that over time, it becomes enlarged or dilated and less able to pump blood through the body.

Some people with Marfan syndrome also have mitral valve prolapse, in which the valve leaflets are enlarged and its chordae tendinae are too long. This structurally altered valve does not close properly, so it makes a clicking sound and then a murmur.

Other heart problems that can affect people with Marfan syndrome include a higher risk of heart attack, an abnormal heart rhythm (arrhythmia), and sudden cardiac death.

Symptoms

The signs and symptoms of Marfan syndrome develop over time. Only about 40% to 60% of patients with Marfan syndrome have symptoms, usually mitral valve prolapse or aorta problems. Other signs of Marfan syndrome may include:

• A tall, thin body frame, long and slender fingers, and long arms and legs.
• A curved or scoliotic spine.
• Chest-wall deformities, such as an indented, narrowed, or protruding sternum.
• Eye or vision problems, such as nearsightedness or a detached retina.
• Disproportionate growth, especially height.
• Flat feet.
• Loose joints or double jointed.
• Shortened, contracted muscles, tendons, and ligaments.

Diagnosis

Marfan syndrome diagnosis is sometimes difficult because the signs and symptoms are usually different in each patient, and it can be confused with other inherited disorders. A complete Marfan syndrome evaluation may include:

• Complete family history, medical history, and genetic evaluation.
• Complete physical examination.
• Echocardiogram and cardiac workup performed by a cardiologist.
• Eye examination performed by an ophthalmologist.
• Skeletal examination performed by an orthopedist.
• CT scan and/or MRI of the heart and aorta.

Patients with Marfan syndrome need regular checkups with their doctor. A chest x-ray and echocardiogram may be needed at least once a year to monitor the heart. Other tests may also be needed, such as an abdominal ultrasound.

Treatment

Treatment of Marfan syndrome may vary, depending on the affected organ systems. A cure does not currently exist, but advances in medical and surgical treatments can improve prognosis and life span. Many patients with Marfan syndrome live late into their 60s and beyond. Because Marfan syndrome affects people in different ways, different types of treatment are needed. Some patients need no treatment. Some patients may need to take beta blocker medicines to lower heart rate and blood pressure. For others, surgery may be needed if an aneurysm forms in the aorta or there is a problem with the aortic or mitral valve. Patients may also need to avoid strenuous exercise or playing contact sports. It is important for patients to learn how to manage their condition and to see their doctor regularly.

A note about pregnancy: During pregnancy (and especially during delivery) stress to the aorta’s walls greatly increases the risk of dissection or rupture. Therefore, pregnancy isn’t advised for women with Marfan syndrome who have a dilated aorta.

Further, people with Marfan syndrome who have an abnormal heart or who’ve had heart surgery for their Marfan syndrome risk developing endocarditis. The American Heart Association no longer recommends taking routine antibiotics before certain dental or surgical procedures except for people at the highest risk for bad outcomes if they develop endocarditis.


Resources

Texas Heart Institute www.texasheartinstitute.com/HIC/Topics/Cond/marfans.cfm
Mayo Clinic www.mayoclinic.org/marfan-syndrome/index.html
The National Marfan Foundation www.marfan.org
American Heart Association www.americanheart.org/presenter.jhtml?identifier=4672
Medline Plus www.nlm.nih.gov/medlineplus/marfansyndrome.html