Ebstein's anomaly is a rare heart defect that's present at birth (congenital). In Ebstein's anomaly, your tricuspid valve — the valve between the chambers on the right side of your heart — doesn't work properly. Blood leaks back through the valve, making your heart work less efficiently. Ebstein's anomaly may also lead to enlargement of the heart or heart failure.

If you have no signs or symptoms of Ebstein's anomaly, careful monitoring of your heart may be all that's necessary. If signs and symptoms become troublesome, or if the heart is enlarging or becoming weaker, treatment for Ebstein's anomaly may be necessary. Treatment options include medications and surgery.

Mild forms of Ebstein's anomaly may not cause symptoms until later in adulthood. Even some people with very abnormal valves may have minimal, if any, problems. Ebstein's anomaly symptoms may develop slowly over many years and include:

• Shortness of breath
• Fatigue, especially with exertion
• Leg swelling
• Heart palpitations or abnormal heart rhythms (arrhythmias)
• A bluish discoloration of the lips and skin caused by low oxygen (cyanosis)

Newborns and infants who are diagnosed with Ebstein's anomaly usually show signs of cyanosis early, in addition to signs and symptoms of heart failure. When signs and symptoms appear at such a young age, this usually indicates a severe defect that requires treatment.

Older children may show signs of heart failure, such as tiring easily or becoming short of breath during play. Their other symptoms may include heart pounding or racing or cyanosis, especially around the lips and fingertips.

When to see a doctor
If you or your child has signs or symptoms of heart failure — such as feeling easily fatigued or short of breath, even with normal activity — or is showing blue skin coloration around the lips and nails (cyanosis), talk to your doctor. He or she may refer you to a doctor who specializes in heart disease (cardiologist).

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Chambers and valves of the heart

Ebstein's anomaly is a heart defect that you have at birth (congenital). To understand how Ebstein's anomaly affects your heart, it helps to know a little about how the heart works to supply your body with blood.

How your heart works
Your heart is made up of four chambers. The top two chambers are the right and left atria (plural for atrium). The two lower chambers, the ventricles, are larger, thicker walled chambers that do the work of pumping blood. Separating the atria from the ventricles are valves, which keep the blood flowing in the right direction through the heart. Each valve consists of two or three strong, thin flaps (leaflets) of tissue. When closed, a valve prevents blood from flowing to the next chamber or from returning to the previous chamber.

Blood returning from your body, which lacks oxygen, flows into the right atrium, through the tricuspid valve and then into the right ventricle, which pumps the blood to your lungs to receive oxygen. On the other side of your heart, oxygen-rich blood from your lungs flows into the left atrium, through the mitral valve and then into the left ventricle, which then pumps the blood to the rest of your body.

What happens in Ebstein's anomaly
In Ebstein's anomaly, the tricuspid valve is farther down into the right ventricle than it would be in a normal heart. This makes it so that a portion of the right ventricle becomes part of the right atrium (becomes atrialized), causing the right atrium to be larger than usual. Because of this, the right ventricle can't work properly.

In addition to the problems with the placement of the tricuspid valve, the valve's leaflets are abnormally formed. This can lead to blood leaking backward (regurgitating) into the right atrium. In severe cases, the leaflets may be tethered to the wall of the right heart, inhibiting their movement and leading to severe leakage of blood into the atrium. One leaflet is often enlarged.

Where the valve is placed and how poorly it's formed varies from person to person. In some people, the valve is only mildly abnormal. In others, the valve may be extremely displaced and malformed, and it may leak severely. The more the valve leaks, the more the right atrium enlarges as it receives more blood. At the same time, the right ventricle enlarges (dilates) as it tries to cope with the leaky valve and still deliver blood to the lungs. Thus, the right-sided chambers of the heart enlarge, and as they do, they weaken, leading to heart failure.

Other heart conditions associated with Ebstein's anomaly
Other heart conditions may be associated with Ebstein's anomaly. Three common conditions are:

• Atrial septal defect. About half the people with Ebstein's anomaly have a hole between the two upper chambers of the heart called an atrial septal defect (ASD). This hole may allow deoxygenated blood in the right atrium to mix with oxygenated blood in the left atrium, decreasing the amount of oxygen available in your blood. This causes a bluish discoloration of the lips and skin (cyanosis). The ASD associated with Ebstein's anomaly can increase your risk of a blood clot passing from the veins in your heart into the blood vessels leading to your brain and causing a stroke. If you have surgery to repair your tricuspid valve, your surgeon will also close the ASD at the same time.
• Abnormal heartbeats (arrhythmias). Some people with Ebstein's anomaly have an abnormal heart rhythm (arrhythmia) characterized by rapid heartbeats (tachycardia). These types of arrhythmias (tachyarrhythmias) can make your heart work less effectively, especially when the tricuspid valve is leaking severely. In some cases, a very fast heart rhythm may cause fainting spells (syncope).
• Wolff-Parkinson-White (WPW) syndrome. Some people with Ebstein's anomaly may also have a condition known as Wolff-Parkinson-White syndrome — an abnormal electrical pathway in the heart. The presence of WPW syndrome can lead to very fast heart rates and fainting spells.

Congenital heart defects, like Ebstein's anomaly, happen early in the development of a baby's heart. It's uncertain what risk factors might cause the defect. Genetic and environmental factors are both thought to play a role. In rare cases, a mother's exposure to lithium or a viral infection may lead to Ebstein's anomaly.

Many people with mild Ebstein's anomaly have few complications. However, you may need to take some precautions in certain situations:

• Being active. If you have mild Ebstein's anomaly with a nearly normal heart size and no heart rhythm disturbances, you can probably participate in most physical activities. Depending on your signs and symptoms, your doctor may recommend that you avoid competitive sports, such as football or basketball. Your cardiologist can help you decide which activities are right for you.

• During pregnancy. In most cases, women with mild Ebstein's anomaly can safely have children. But pregnancy does have its risks. Being pregnant puts additional strain on your heart and circulatory system not only during pregnancy, but also during labor and delivery and for a period of time after your baby's birth. There is an increased risk of stroke if you have a hole between the upper chambers of the heart (atrial septal defect).

  Rarely, women with Ebstein's anomaly develop severe complications that can cause death during pregnancy. If you plan on becoming pregnant, be sure to talk to your cardiologist ahead of time. He or she can tell you if it's safe for you to become pregnant and help decide how much extra monitoring you may need throughout pregnancy and childbirth.

Other complications that may result from Ebstein's anomaly include heart failure, rhythm problems and, less commonly, sudden cardiac arrest or stroke.

If you don't have any signs or symptoms that may indicate a heart defect, the first clue may be an abnormal heart sound or heart murmur discovered during a regular checkup. However, most people with a heart murmur don't have any heart defects. A doctor uses a stethoscope to listen to your heart and evaluate the quality, frequency and duration of any abnormal sounds.

If your doctor suspects an underlying problem, such as congenital heart disease, or if you have other signs and symptoms that may suggest Ebstein's anomaly, your doctor may recommend the following tests:

• Chest X-ray. A chest X-ray shows a picture of your heart, lungs and blood vessels. It can reveal if your heart is enlarged, which may be due to Ebstein's anomaly.
• Echocardiogram. This noninvasive exam uses ultrasonic waves to show images of your heart. It can detect most congenital heart defects. Ultrasonic waves are transmitted through a device called a transducer, which a technician will move over your heart. The echoes of the waves are recorded and produce images of your heart on a computer monitor so that your doctor can see the valves and chambers of your heart.
• Electrocardiogram (ECG). An ECG uses sensors (electrodes) attached to your chest and limbs to measure the timing and duration of your heartbeat. An ECG can help your doctor detect irregularities in your heart's rhythm and structure, and offer clues as to the presence of an extra pathway.
• Holter monitor testing. This is a portable version of an ECG. It's especially useful in diagnosing rhythm disturbances that occur at unpredictable times. You wear the monitor under your clothing. It records information about the electrical activity of your heart as you go about your normal activities for a day or two.
• Cardiac catheterization. Doctors rarely use this more invasive technique for Ebstein's anomaly. In a few cases, however, a person may need cardiac catheterization to obtain additional information, to confirm findings from other tests, or to check heart arteries. During cardiac catheterization, a slender, flexible tube (catheter) is inserted into a vein or artery at the top of your leg (groin) or into your arm. Aided by X-ray images on a monitor, your doctor threads the catheter through that artery until it reaches your heart. A special dye injected through the catheter helps your doctor see the blood flow through your heart, blood vessels and valves, and allows your doctor to check for abnormalities inside the heart and lungs.

Treatment of Ebstein's anomaly depends on the severity of the defect and your signs and symptoms. The goal of treatment is to reduce your symptoms and avoid future complications, such as heart failure and arrhythmias. Treatments may include:

Regular monitoring
If you have no signs or symptoms or abnormal heart rhythms, your doctor may recommend only careful monitoring of your heart condition with regular checkups. Checkups typically include a physical exam, electrocardiogram, chest X-ray, echocardiogram and, if necessary, a Holter monitor test. Your doctor may also ask you to undergo an exercise test, such as walking on a treadmill. This test checks your heart's response to physical activity.

Medications
If you have heart rhythm disturbances, medications may help control heart rate and maintain normal heart rhythm. Doctors commonly use medications, including calcium channel blockers, beta blockers, digitalis and anti-arrhythmic drugs, such as amiodarone.

Your doctor may also prescribe medications for signs and symptoms of heart failure, if you need them. These may include diuretics and other medications.

Surgical heart repair
Your doctor may recommend surgical repair when your signs and symptoms are troublesome or when your heart begins to enlarge and overall heart function begins to decrease. Because Ebstein's anomaly is rare, choose a surgeon who's familiar with the defect and who has experience performing procedures to correct it. Different types of procedures can be used to surgically treat Ebstein's anomaly and associated defects, including:

• Tricuspid valve repair. This involves reducing the size of the valve opening and allowing the existing valve leaflets to come together to work properly. This procedure is usually done when there's enough valve tissue to allow for repair.
• Tricuspid valve replacement. If the existing valve can't be repaired, it may be replaced by removing the deformed valve and inserting either a mechanical valve or a specially treated biological tissue (bioprosthetic) valve. If a mechanical valve is used, you'll need to take a blood-thinning medication for the rest of your life.
• Closure of the atrial septal defect (ASD). If an ASD is present, your surgeon can close the hole during surgery to repair or replace the defective valve.
• Maze procedure. Another procedure that doctors may perform during valve repair or replacement surgery is called a maze procedure. It's used to help correct fast heart rhythms in the atrium (atrial tachyarrhythmias). To do the procedure, your surgeon makes a series of incisions in the right atrium with a scalpel or a device that destroys tissue by freezing it. When these incisions heal, the scars create a barrier of tissue in your heart that causes it to beat at a normal rate. The Maze procedure is an open-heart surgery.

Radiofrequency catheter ablation
Radiofrequency catheter ablation is another procedure that can help treat a fast heartbeat or WPW syndrome. In this procedure, one or more catheters are threaded through your blood vessels to your inner heart, where the electrical impulses that cause your heart to beat are generated. Electrodes at the catheter tips are heated with radiofrequency energy. This destroys (ablates) a small spot of heart tissue and creates an electrical block along the pathway that's causing your arrhythmia. Usually, this stops your arrhythmia.

Heart transplantation
If you have Ebstein's anomaly with a severely malformed valve and poor heart function, a heart transplant may be necessary.

If you or your child has mild Ebstein's anomaly, here are some steps that may help you cope:

• Follow up on medical care. Be sure to follow up with your cardiologist or pediatrician for regular evaluations. Be an active participant in monitoring the condition and report any new or worsening signs or symptoms. Timely treatment can keep the condition from becoming worse.
• Take medications as prescribed. Taking medications at the right dose and the right time can help improve symptoms such as racing heartbeats, fatigue and shortness of breath.
• Stay active. Be as physically active as your doctor allows. Exercise can help strengthen your heart and improve your blood circulation. If you're a parent of a child with Ebstein's anomaly, it's natural to want to protect your child from harm. But remember that your child needs to live life as normally as possible. Encourage playtime with breaks as needed. Ask your doctor for a note you can give to your child's teachers or caregivers describing any restrictions on his or her physical activity.
• Develop a support network. Although many people with congenital heart defects lead normal, healthy lives, living with a heart defect isn't always easy, particularly when you or your child needs continued specialized care. The physical, emotional and financial stress of coping with a serious health condition can be overwhelming. Having family and friends you can rely on is critical to successful coping. In addition, you may wish to ask your doctor about local support groups that may be helpful. Support groups can be a great source of practical information, comfort and friendship.