Related terms: connective tissue disorder, genetic defect, congenital
| February 2012–in the news |
Getting to the heart of Marfan syndrome
Some doctors might see a patient with Marfan syndrome once a year. But Dr. Joseph Coselli sees one or more a week and with his team has treated hundreds of patients. He also participates in the GenTAC (National Registry of Genetically Triggered Thoracic Aortic Aneurysms and Conditions) study, and seeks to enroll as many of his patients as possible. Read the article from BCM News.
Marfan syndrome is a rare disorder that causes the connective tissue in the body to be weaker than it should be. Connective tissue is the material that holds together many structures in your body, such as tendons, ligaments, cartilage, blood vessels, heart valves, and more. 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.
What causes Marfan syndrome?
Marfan syndrome is thought to be an inherited disease that is caused by a defect in a gene. About 50,000 people in the United States are diagnosed with the condition each year. Marfan syndrome can affect both men and women. Because the gene defect can be passed down to children, Marfan patients should talk to their doctor and a genetic counselor before having children. In about 25% of Marfan patients, neither parent had the condition. In these patients, the condition is thought to develop because of a mutation in the egg or the sperm.
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 the connective tissue. This protein is called fibrillin. Without enough proper fibrillin, the walls of the major arteries are weakened. If the aorta (the main blood supplier to the body) is affected, it gets bigger (or dilates), making it weaker. The weakened area of the aorta can bulge outward, creating an aortic aneurysm. Or, the aorta can tear, and blood can leak through these tears and between the tissue of the aortic wall. This is called aortic dissection.
If the aorta is stretched and weakened, this can also affect the aortic valve. In some patients, blood leaks backward through the valve instead of moving in the proper one-way, forward flow. This is called regurgitation. If too much blood flows backward, only a small amount can travel forward to your body's organs. Your heart tries to make up for this by working harder, but with time your heart will become enlarged (dilated) and less able to pump blood through the body.
Some people with Marfan syndrome also have mitral valve prolapse (MVP). Mitral valve prolapse means that one or both of the valve flaps (called cusps or leaflets) are enlarged, and the flaps' supporting tendon-like cords (called chordae tendineae) are too long. Instead of closing evenly, one or both of the flaps collapse or bulge into the left atrium. MVP is often called click-murmur syndrome because when the valve does not close properly, 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 (called arrhythmia), and sudden cardiac death.
What are the signs and symptoms of Marfan syndrome?
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 problems with the aorta.
Other signs of Marfan syndrome may include
- A tall and thin body frame, long and slender fingers, and long arms and legs.
- A curved spine (called scoliosis).
- Chest-wall deformities, such as a breast bone (sternum) that is caved in (indented) or sticking out (protruding). If the breast bone is indented, it may also be very narrow.
- Eye or vision problems, such as nearsightedness (only being able to see objects close up) or a detached retina that can lead to sudden loss of eyesight. A detached retina can be repaired by an eye surgeon.
- Disproportionate growth, meaning people with Marfan syndrome are usually very tall. This may be especially noticeable in children, because they may be much taller than other children their own age.
- Flat feet.
- Loose joints (called joint laxity) or being double jointed.
- Shortened muscles, tendons, and ligaments (called contracture).
How is Marfan syndrome diagnosed?
The signs and symptoms of Marfan syndrome can be different in each patient, so diagnosing the condition can be hard. Here is a list of some of the tests that may be used to diagnose Marfan syndrome:
- A physical examination and a history that includes information about your family history of diseases.
- Using a stethoscope, the doctor will listen to your heart. This is called auscultation, which means the study of heart sounds. Doctors are able to hear any abnormal heart sounds through the stethoscope.
- Echocardiography can be used to see valve function, heart wall motion, and overall heart size.
- Computed tomography (CT or CAT scan) is an x-ray technique that uses a computer to create cross-sectional images of the body, in this case the aorta.
- Magnetic resonance imaging (MRI) is a scan that lets doctors see inside your body without having to perform surgery. The test gives doctors a detailed picture of the heart and the aorta.
How is Marfan syndrome treated?
Patients with Marfan syndrome will need to visit their doctor regularly. Tests such as chest X-rays and an echocardiogram may be needed at least once a year to monitor the heart and how it is working. Other tests may also be needed, such as an abdominal ultrasound.
Because Marfan syndrome affects people in different ways, different types of treatment are needed. Some patients may not need any treatment at all. Some patients may need to take beta-blockers to lower heart rate and blood pressure. And for others, surgery may be needed if an aneurysm forms in the aorta or there is a problem with the aortic or mitral valves.
If you have Marfan syndrome, you should talk to your doctor about taking antibiotic medicine before dental procedures or general surgery. The medicine will prevent any bacteria that might enter the bloodstream during the procedure from causing an infection in the heart valves.
Patients may also need to avoid strenuous exercise or playing any contact sports. Women should talk to their doctor and a genetic counselor before becoming pregnant.
Many patients with Marfan syndrome live late into their 60s and beyond. It is important for patients to learn how to manage their condition and to see their doctor regularly.
See also on this site: Aneurysms, Mitral Valve Prolapse, Diagnostic Tests and Procedures
See on other sites:
National Heart Lung and Blood Institute
What Is Marfan Syndrome?
The National Marfan Foundation
Updated August 2012