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Marfan Syndrome

(Marfan's Syndrome)


Frank Pessler

, MD, PhD, Helmholtz Centre for Infection Research

Reviewed/Revised Dec 2022
Topic Resources

Marfan syndrome is a rare hereditary disorder of connective tissue, resulting in abnormalities of the eyes, bones, heart, blood vessels, lungs, and central nervous system.

  • This syndrome is caused by mutations in the gene that codes for a protein called fibrillin.

  • Typical symptoms can range from mild to severe and include long arms and fingers, flexible joints, and heart and lung problems.

  • The diagnosis is based on symptoms and family history.

  • Most people with this syndrome live into their 70s.

  • There is no cure for Marfan syndrome or any way to correct the abnormalities in the connective tissue.


Marfan syndrome is caused by mutations in the gene that codes for a protein called fibrillin. Fibrillin helps connective tissue maintain its strength. Connective tissue Overview of Connective Tissue Disorders in Children Connective tissue is the tough, often fibrous tissue that binds the body's structures together and provides support and elasticity. Muscles, bones, cartilage, ligaments, and tendons are built... read more is the tough, often fibrous tissue that binds the body's structures together and provides support and elasticity.

If the fibrillin gene is mutated, some fibers and other parts of connective tissue undergo changes that ultimately weaken the tissue. The weakening affects bones and joints as well as internal structures, such as the heart, blood vessels, eyes, lungs, and central nervous system (the brain and spinal cord). Weakened tissues stretch, distort, and can even tear. For example, the aorta (the main artery of the body) may weaken, bulge, or tear. Weak tissues in a heart valve can cause the valve to leak. Connective tissues that join structures may weaken or break, separating formerly attached structures. For example, the lens or retina of the eye may separate from its normal attachments.

Symptoms of Marfan Syndrome

Symptoms of Marfan syndrome can range from mild to severe. Many people with Marfan syndrome never notice symptoms. In some people, symptoms may not become apparent until adulthood.

Musculoskeletal problems

People with Marfan syndrome are taller than expected for their age and family. Their arm span (the distance between fingertips when the arms are outstretched) is greater than their height. Their fingers are long and thin. Often, the breastbone (sternum) is deformed and pushed outward or inward. The joints may be very flexible. Flat feet Pes planus (flat feet) Clubfoot (talipes equinovarus) is a birth defect in which the foot and ankle are twisted out of shape or position. Birth defects, also called congenital anomalies, are physical abnormalities... read more Pes planus (flat feet) , a deformity of the knee joint that causes the knee to bend backward, and a humpback with an abnormal curve of the spine (kyphoscoliosis Scheuermann Disease Kyphosis is an abnormal curving of the spine that causes a humpback. (See also Overview of Bone Disorders in Children.) The upper back normally curves forward somewhat. Some children have a... read more ) are common, as are hernias. Usually, the person has little fat under the skin. The roof of the mouth is often high.

Heart problems

The most dangerous complications develop in the heart and lungs. Weakness may develop in the connective tissue of the wall of the aorta. The weakened wall may result in blood seeping between the inner layers of the aorta’s wall (aortic dissection Aortic Dissection An aortic dissection is an often fatal disorder in which the inner layer (lining) of the aortic wall tears and separates from the middle layer of the aortic wall. Most aortic dissections occur... read more ), which causes a tear, or in a bulge (aneurysm Overview of Aortic Aneurysms and Aortic Dissection The aorta, which is about 1 inch (2.5 centimeters) in diameter, is the largest artery of the body. It receives oxygen-rich blood from the left ventricle of the heart and distributes it to all... read more ) that can rupture. These problems sometimes develop before a child is 10 years old.

Lung problems

Air-filled sacs (cysts) may develop in the lungs. The cysts may rupture, bringing air into the space that surrounds the lungs (pneumothorax Pneumothorax A pneumothorax is partial or complete collapse of the lung due to the presence of air between the two layers of pleura (thin, transparent, two-layered membrane that covers the lungs and also... read more Pneumothorax ). These disorders can cause pain and shortness of breath.

Eye problems

The lens of one or both eyes may be displaced (dislocated). People are very nearsighted (unable to see distant objects clearly). The light-sensitive area at the back of the eye (retina) may detach from the rest of the eye (see Detachment of the Retina Detachment of the Retina Detachment of the retina is separation of the retina (the transparent, light-sensitive structure at the back of the eye) from the underlying layer to which it is attached. People notice a sudden... read more ). Displacement of the lens and detachment of the retina may cause permanent loss of vision.

Spinal cord problems

The sac that surrounds the spinal cord may widen (called dural ectasia). Dural ectasia is common in people with Marfan syndrome and most frequently occurs in the lower portions of the spine. It may cause headache, lower back pain, or other neurologic problems such as bowel or bladder weakness.

Diagnosis of Marfan Syndrome

  • A doctor's evaluation

  • Genetic testing

  • Echocardiography

  • Magnetic resonance imaging (MRI)

  • X-rays

  • Eye examinations

Doctors may suspect the diagnosis of Marfan syndrome if an unusually tall, thin person has any of the characteristic symptoms or if Marfan syndrome has been recognized in other family members (first-degree relatives such as the father, mother, or a sibling). Doctors also base the diagnosis on specific criteria regarding the extent to which certain organ systems, such as the heart, eyes, and bones, are affected.

Doctors may do an analysis of genes, usually from a sample of blood, to help diagnose Marfan syndrome.

Doctors monitor for complications that can cause serious symptoms. People should have their heart, bones, and eyes checked every year to see if they are getting worse. This annual evaluation usually includes echocardiography Echocardiography and Other Ultrasound Procedures Ultrasonography is a type of medical imaging that uses high-frequency (ultrasound) waves to produce a moving image of internal organs and other tissues. Echocardiography is ultrasonography of... read more Echocardiography and Other Ultrasound Procedures of the heart and aorta; x-rays of the hand, spine, pelvis, chest, foot, and skull; and an eye examination. MRI Magnetic Resonance Imaging (MRI) Magnetic resonance imaging (MRI) is a type of medical imaging that uses a strong magnetic field and very high frequency radio waves to produce highly detailed images. During an MRI, a computer... read more Magnetic Resonance Imaging (MRI) can also be done to evaluate heart and brain problems. Echocardiography and eye examinations are also done whenever symptoms develop.

Prognosis for Marfan Syndrome

Years ago, most people with Marfan syndrome died in their 40s. Today, people who have Marfan syndrome have nearly the same life expectancy as people who do not have this condition. Prevention of aortic dissection and rupture probably explains why the life span has been lengthened.

Treatment of Marfan Syndrome

  • Beta-blockers

  • Sometimes surgical repair of the aorta and valves

  • Sometimes a brace and sometimes surgical repair for curving of the spine

There is no cure for Marfan syndrome or any way to correct the abnormalities in the connective tissue.

Treatment of Marfan syndrome is aimed at preventing and/or fixing dangerous complications.

Beta-blockers (such as atenolol and propranolol) are medications that slow the heart rate and decrease the force of heart contractions. These medications are given to make blood flow more gently through the aorta. However, if the aorta has widened or developed an aneurysm, the affected section should be repaired or replaced surgically. Severe valve regurgitation is also surgically repaired. Pregnant women are at especially high risk of complications with their aorta, so repair of the aorta before conception should be discussed. Angiotensin II receptor blockers (such as losartan and candesartan) are other medications that may be given to lower blood pressure.

A displaced lens or retina can usually be reattached surgically.

A brace is used to treat abnormal curving of the spine (scoliosis Scoliosis Scoliosis is abnormal curvature of the spine. Scoliosis can be present at birth or can develop during adolescence. Mild forms may cause only mild discomfort, but more severe forms can cause... read more Scoliosis ) for as long as possible. However, some children need a surgical procedure to correct the curve.

People should receive genetic counseling. People and their families may obtain additional information from the The Marfan Foundation.

More Information

The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

  • The Marfan Foundation: A resource providing support, education, and community information about Marfan syndrome

Drugs Mentioned In This Article

Generic Name Select Brand Names
HEMANGEOL, Inderal, Inderal LA, Inderal XL, InnoPran XL
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