Marfan Syndrome

What is Marfan Syndrome?

Marfan syndrome affects many parts of the body, including the heart, blood vessels, skeleton, and eyes. 1 in 5,000 people in the United Kingdom have Marfan syndrome and both men and women can be affected.

People with Marfan syndrome produce abnormal ‘connective tissue’. Connective tissue helps hold the body together, binding tendon to muscle and muscle to bone and is made of microscopic fibres.

This tissue provides the stretchy strength of tendons and ligaments around joints and in blood vessel walls. In Marfan syndrome, a fibre called fibrillin is made abnormally which makes weaker tissue.

Marfan syndrome is inherited from parents in 75% of cases, usually due to a mutation in the fibrillin gene. In the remaining 25% of cases it is caused by a new or ‘de novo’ mutation. The condition is inherited and, as such, children of a person with Marfan syndrome have a 50% chance of developing the condition.


The severity and pattern of disease are variable in Marfan syndrome, even within families. Diagnosis requires a careful physical examination and co-operation of different medical specialties. People with Marfan syndrome may be very tall and suffer from spine problems. Their arms, legs and fingers may be long and their arm span may even be longer than their height. The joints of the hands and wrist may also be very flexible. The roof of the mouth can be high and arched and the teeth may seem overcrowded. There may also be problems with vision caused by problems with the lens of the eye.

One of the main concerns in Marfan syndrome is that the main blood vessel in the body, the aorta, can become stretched, enlarged and may tear (aortic dissection) or burst (aortic rupture). This can be very dangerous. People with Marfan syndrome may also develop leaking heart valves that can be heard by a doctor as a heart murmur. Enlargement of the aorta can also cause the aortic valve to become leaky (aortic regurgitation). The function of the aortic valve is to prevent blood from flowing back into the heart once it has been pumped out. Leakage of blood back into the heart can cause breathlessness. Leaking of the mitral valve can also be caused by Marfan syndrome. Constant leaking of the mitral valve causes the main pumping chamber to work harder and may again cause breathlessness sometimes with palpitations.

Not everyone with Marfan syndrome has all of these problems.


Diagnosis is made after a careful physical examination, particularly focusing on the three main systems involved:

  • Eyes
  • Heart
  • Skeleton (including the jaw).

Certain tests such as an Echocardiogram (an ECG is insufficient); chest and skeletal X-rays; and a careful eye examination using a slit lamp, are useful in making the diagnosis.

A genetic test can provide a definite diagnosis in at least 90% of cases.

What treatment is available?

The complications of Marfan syndrome can be corrected. The importance of diagnosis is to allow careful observation so that the life-threatening risks of aortic dissection or rupture can be avoided. Enlargement of the aorta usually occurs very slowly, so an ECHO once a year will identify patients with this problem. Tablets called beta-blockers can slow the enlargement down. If dangerous enlargement occurs then plans can be made for an operation to replace that part of the aorta. Mitral and/or aortic valve can be replaced or repaired during an operation if needed.

Eye, mouth and skeleton problems are not life-threatening and each problem can be corrected if necessary.

There are only four rare complications requiring emergency care:

  • Tear of the aorta – this may cause severe chest and/or back pain and even a collapse.
  • Collapse of lung – this may occur during periods of exertion and presents with severe breathlessness. You may become blue and complain of chest pain.
  • Glaucoma – the lens problem may produce a sudden increase of pressure in the eye and cause acute eye pain.
  • Dislocations – loose ligaments do not provide adequate support for joints, and can cause a joint to become separated, known as dislocation.