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Health Information For Parents
Tetralogy of Fallot (fah-LO) is a congenital (present at birth) heart defect. In tetralogy of Fallot (TOF), four related heart defects change the way blood flows to the lungs and through the heart.
TOF is repaired through open-heart surgery soon after birth or later in infancy. Some infants need more than one heart surgery. Most babies who are treated do very well, but will need regular follow-up visits with a heart specialist.
In most cases of tetralogy of Fallot, too little blood goes to the lungs. This low-oxygen (blue) blood then circulates to the rest of the body, and too little oxygen reaches the body tissues.
Babies with TOF often have cyanosis — a blue or purple tint to the baby’s skin, lips, and fingernails.
If tetralogy of Fallot isn’t treated, a child may have:
Children whose TOF isn’t fixed usually become increasingly blue over time and have difficulty participating in physical activities (like playing sports). Most babies who have surgery to correct the defect do very well and can participate in normal kid activities.
“Tetralogy” means a combination of four related symptoms or problems. The four problems of tetralogy of Fallot are:
With pulmonary stenosis, the heart has to work harder than normal to pump blood to the lungs. There is also less blood traveling to the lungs because the pathway is narrowed. This leads to less blood becoming red, oxygen-rich blood. Sometimes, infants with TOF have pulmonary atresia, where the pulmonary valve is completely sealed off.
Cyanosis is a very common sign. Healthy babies can sometimes also have bluish skin around the mouth or eyes from prominent veins under the skin, but their lips and tongue look pink. Babies who have low oxygen levels in the blood usually have blue lips and tongues in addition to bluish skin.
A child with TOF might have sudden episodes of deep cyanosis, called “hypercyanotic spells” or “Tet spells,” during crying or feeding. Older children who have Tet spells will often instinctively squat down, which helps to stop the spell.
Other signs include:
The specific cause of tetralogy of Fallot isn’t always known. The TOF changes in a baby’s heart develop in the early weeks of pregnancy. In some cases, there are genetic causes of TOF — for example, children with Down syndrome or DiGeorge syndrome are more likely to have TOF. Someone born with TOF is more likely to have a child or sibling with it. Each year, roughly 1 out of every 2,500 babies born in the United States have the condition.
Babies of mothers who get rubella (German measles) or other viral illnesses during their pregnancies are at a higher risk for TOF. Other pregnancy-related risks include poor nutrition, alcohol abuse, poorly controlled diabetes, and the mother’s age (over 40). Certain environmental factors, such as air pollution, also may increase a mother’s chances of having a baby with TOF.
Most of the time, a child with TOF doesn’t have any other birth defects.
Doctors might do several tests to find out if a baby has tetralogy of Fallot and to get more details about the baby’s heart and blood vessels, including:
Doctors repair tetralogy of Fallot through open-heart surgery soon after birth or later in infancy, depending on the baby’s health and weight and severity of defects and symptoms.
The two surgical options are:
These repairs also fix the two remaining defects (overriding aorta and right ventricular hypertrophy). Because the right ventricle doesn’t have to work as hard to pump blood into the lungs, the thickness of the ventricle wall will decrease. And the patched VSD prevents blood with low oxygen from flowing into the aorta.
The full repair is done later when the baby grows stronger.
Most babies whose tetralogy of Fallot is repaired do very well, but will need regular follow-up visits with a heart specialist.
Heart defects happen when there’s a problem with a baby’s heart development during pregnancy. Most heart defects can be treated during infancy.
Ventricular septal defect (VSD) â also known as a “hole in the heart” â is a congenital heart defect. Most VSDs are diagnosed and treated successfully.
Pulmonary stenosis means the pulmonary valve is too small, narrow, or stiff. Many people have no symptoms, but kids with more severe cases will need surgery so that blood flows properly through the body.
An arrhythmia is an abnormal heartbeat usually caused by an electrical “short circuit” in the heart. Many are minor and not a health threat, but some can indicate a more serious problem.
If your child has a birth defect, you don’t have to go it alone – many people and resources are available to help you.
Heart murmurs are very common, and most are no cause for concern and won’t affect a child’s health.
The heart and circulatory system are our body’s lifeline, delivering blood to the body’s tissues. Brush up on your ticker with this body basics article.
Coarctation of the aorta (COA) is a narrowing of the aorta, the major blood vessel that carries blood away from the heart to the body.
Is your child scheduled to have an ECG? Find out how this test is performed and when you can expect the results.
Atrial septal defect (ASD) â also known as a “hole in the heart” â is a type of congenital heart defect. Most ASDs are diagnosed and treated successfully.
Your heart beats and sends oxygen throughout your entire body. Find out how it works and how heart problems can be fixed.
Your heart beats and sends blood all around your body. Find out more about the heart, from A to Z, in this glossary.
When someone has coarctation of the aorta, that person’s aorta (the major blood vessel that carries blood away from the heart to the body) is narrowed at some point.
Atrial septal defect, or ASD, is a heart defect that some people are born with. Most ASDs are diagnosed and treated successfully with few or no complications.
Ventricular septal defect, or VSD, is a heart condition that a few teens can have. Find out what it is, how it happens, and what doctors do to correct it.
The heart and circulatory system (also called the cardiovascular system) make up the network that delivers blood to the body’s tissues.
Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.
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