Marfan syndrome

What is Marfan syndrome, and how common is it?

Marfan syndrome (sometimes called Marfan's) is an inherited condition of the connective tissue, the tissue that supports your bones, muscles and organs. You are born with it¹. It mainly affects the aorta (the large artery that carries blood from the heart), the skeleton and the eyes².

About 1 in 5,000 people have it³. How it shows up varies widely. Some people have mild signs in only one or two parts of the body, while others have serious problems in several organs⁴. Two people with Marfan syndrome can therefore look and feel quite different.

What causes Marfan syndrome, and who gets it?

Marfan syndrome is caused by a change in a gene called FBN1. This gene makes fibrillin-1, a protein that forms elastic fibres in connective tissue¹. With the gene change, there is less fibrillin-1 or it doesn't work properly².

It is passed on in an autosomal dominant way, which means one changed copy of the gene is enough. A child of a parent with Marfan syndrome has a 1 in 2 (50%) chance of inheriting it². It can help to note down any family history of Marfan syndrome, or of aortic aneurysm or dissection, to share with your health professionals.

How does Marfan syndrome show up, and what can make it serious?

Bone and joint signs are often the first clue⁵. People with Marfan syndrome are often tall and slender, with long limbs, long fingers and toes, loose joints and an arm span greater than their height⁶. A curved spine, a chest wall that sticks out or sinks in, and flat feet (pes planus) are also common⁵. Other signs include stretch marks, hernias, a heart murmur and breathlessness⁷. Not everyone has the full range of features². Doctors use an agreed set of criteria, called the Ghent criteria, to help make the diagnosis⁶.

Some features mark the condition as more serious:

• The aorta. Widening of the aorta close to the heart can cause a leaking heart valve or a tear in the aortic wall (aortic dissection). This is the main cause of illness and death in Marfan syndrome, and rarely a sudden heart problem is the first sign².
• Signs of a tear. Chest pain is the most common symptom, and some people feel a sudden, crushing pain⁸. Back pain or fainting can also be signs⁹. A dissection is treated with surgical repair, and the risk rises with the size of the aorta and with pregnancy⁷.
• Back pain with headaches. Long-lasting back pain, or headaches that are worse when upright, can reflect dural ectasia, a widening of the sac around the spinal cord that is common in Marfan syndrome⁵.
• Eye problems. These are common and mostly appear before age 30, so regular eye checks from early childhood are recommended⁵. Glaucoma and retinal detachment (both causing vision problems) can occur⁷.

Marfan syndrome overlaps with other conditions that affect the aorta, including Loeys–Dietz syndrome, Shprintzen-Goldberg syndrome, the MASS phenotype and familial thoracic aortic aneurysm and dissection⁶.

What can help first with Marfan syndrome?

Staying active in the right way is the main step you can take yourself. Mild to moderate activities such as swimming, walking and cycling are generally encouraged, while strenuous activity and contact sports are best avoided¹⁰. Contact sports, competitive sports and isometric exercise (static, straining effort) are the ones to avoid⁶. They put extra stress on the aorta, risk chest or eye injury, and can damage loose ligaments and joints¹¹.

Because joints can be unstable, advice may need to be tailored to the individual, especially for children and young people¹¹. A cardiologist (a heart doctor) can advise which sports and activities suit each person¹².

Some blood pressure medicines (angiotensin receptor blockers) act on aortic growth, with a bigger effect in people with a confirmed FBN1 change³.

What helps if that isn't enough?

If the aorta tears, the repair is surgical and immediate. Dissection or rupture becomes more likely as the aorta gets larger and during pregnancy, and this is managed by a cardiologist⁷.

Activity advice stays the same: avoid contact, competitive and isometric exercise, and take care during activity to avoid unnecessary strain on your joints⁷. For a child aged 12 to 16, PE and out-of-school activities become more competitive, so what they join in may need adapting, or they may take up a different activity¹¹.

It isn't clear yet which treatments help flat feet or foot pain in Marfan syndrome, including insoles, footwear and foot surgery.

What is the outlook for Marfan syndrome?

The outlook depends mainly on the aorta. Aortic complications, above all dissection, can lead to early death or disability³. A tear in an aortic aneurysm (a bulge in the wall of the aorta) is the greatest threat to life⁴. The most severe form appears in newborns and generally has a poor prognosis, so outlook varies widely between people⁴.

Marfan syndrome is present from birth¹, so it's something to manage over time. Keeping up regular moderate activity and a balanced diet supports your general health¹². Staying active also helps keep your heart and circulation fit, while steering clear of activities that substantially raise the risk of dissection².