Sunday, July 21, 2002

Question: Please, what specialist would be the best for an individual with Marfan syndrome? What can be done to treat this disorder?

C. Blok
Jacksonville

Answer: Marfan syndrome is a rare congenital abnormality that afflicts about 1 in 10,000 live births. The Olympic volleyball player Flo Hyman succumbed to this condition. There is speculation Abraham Lincoln may have been affected. Clinical manifestations are numerous and varied. The most prominent features include enlargement of the aorta, the main blood vessel carrying blood from the heart to the body, heart valve prolapse, dislocation of the lenses in the eyes, nearsightedness and spontaneous collapse of the lung.

A number of musculoskeletal features are suggestive of the condition, including tall stature, long arms, legs and fingers, scoliosis or curvature of the spine, chest deformities and dental crowding. It may also predispose one to sleep apnea or osteoporosis.

Otherwise healthy individuals may share these physical features without any significant risk of the potentially serious non-musculoskeletal manifestations of the condition.

The fundamental abnormality in Marfan syndrome is a defect in the gene encoding the structural protein fibrillin. This protein is present throughout the body and contributes to a latticework of connective tissue that supports the organs of the body. The abnormality tends to be inherited. Offspring of an affected individual have a 50/50 chance of being affected. The condition affects people differently, in some cases even within the same family. This most likely represents an interaction with other genes influencing the connective tissues of the body.

Twenty-five percent of cases arise due to spontaneous mutations in reproductive cells. Thus the absence of a family history does not preclude the diagnosis.

The average life expectancy of persons with Marfan syndrome is reduced by about a third in the absence of appropriate surveillance, preventive medical care and timely cardiac surgery.

More than 90 percent of the deaths are related to cardiovascular problems. Most of these problems result from progressive enlargement of the aorta at its junction with the heart. This poses a risk of tearing or rupture of the aorta, a frequently fatal event. Congestive heart failure and arrhythmias can also develop from severe leaking of the aortic valve or a prolapsing mitral valve.

Fortunately, with timely diagnosis of the condition, proper surveillance, preventive medications to slow the rate of aortic enlargement, and timely prophylactic surgery to prevent rupture of the aorta or to fix leaking heart valves, a patient's life expectancy approaches that of persons who are not afflicted with Marfan syndrome.

The non-cardiovascular manifestations may also require intervention, including surgery to replace dislocated ocular lenses, treatment for detached retina, surgery or bracing to correct scoliosis, as well as treatment for collapsed lung, spinal cord compression or dislocated joints.

Despite a thorough understanding of the genetic cause of the condition, the diagnosis of Marfan syndrome is still based on clinical assessment. Occasionally, a definitive diagnosis is elusive. Under these circumstances, genetic testing may play a role.

With regards to your primary concern, I suggest the situation is best handled by an experienced multidisciplinary team dedicated to the management of such individuals and their families. Key personnel should have experience in treating such patients and include cardiologists, cardiothoracic surgeons, a medical geneticist with an interest in this area, an ophthalmologist with experience in evaluating such individuals, a competent echocardiography laboratory to perform serial ultrasound studies of the heart, and experienced consultants including orthopedics, rheumatology, radiology and obstetrics and gynecology.

Unfortunately, such specialty clinics are difficult to find. One of the nation's leaders in such clinics is at Johns Hopkins University in Baltimore. Preliminary attempts at developing a multidisciplinary program involving individuals from diverse medical institutions in Jacksonville are under way. In the interim, finding a physician with experience in evaluating and managing patients with Marfan syndrome and related connective tissue disorders is essential. Usually, that individual will be an adult or pediatric cardiologist or a medical geneticist.

Keith R. Oken, M.D.
Cardiologist
Mayo Clinic, Jacksonville