Mild forms of Ebstein's anomaly may not cause symptoms until later in adulthood. If signs and symptoms are present, they may include:
- Shortness of breath, especially with exertion
- Heart palpitations or abnormal heart rhythms (arrhythmias)
- A bluish discoloration of the lips and skin caused by low oxygen (cyanosis)
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).
Ebstein's anomaly is a heart defect that you have at birth (congenital). Why it occurs is still unknown. 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 called the right and left atria ("atria" is 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.
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 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 of those 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).
- 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, such as 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. People with a family history of heart defects may be more likely to have Ebstein's anomaly. A mother's exposure to certain medications, such as lithium or benzodiazepines, has been associated with Ebstein's anomaly in the child.
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 doctor can help you decide which activities are right for you.
During pregnancy. In many cases, women with mild Ebstein's anomaly can safely have children. But pregnancy does have risks. If you plan on becoming pregnant, be sure to talk to your doctor 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.
Being pregnant puts additional strain on your heart and circulatory system not only during pregnancy, but also during labor and delivery. However, vaginal delivery may be possible. Rarely, severe complications can develop that can cause death to the mother or baby.
Other complications that may result from Ebstein's anomaly include heart failure, heart rhythm problems and, less commonly, sudden cardiac arrest or stroke.