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Tetralogy Of Fallot In Children

What is tetralogy of Fallot?

  • Tetralogy of Fallot, also called TOF, is a congenital heart disease. A congenital heart disease is one that a person is born with. TOF is the most common heart disease that causes cyanosis (bluish color of the skin). Cyanosis occurs when blood from the right side of the heart goes directly to the left side. The blood does not pass through the lungs, and it will not carry enough oxygen to give to the body. Normally, veins bring blood from your child's body to his heart. The blood from the body enters the right atrium first, then is pumped down into the right ventricle. The right ventricle then pumps the blood into the lungs where oxygen is added. The blood goes back to the heart into the left atrium and down into the left ventricle. The left ventricle then pumps the blood out to the body where the oxygen can be used.

  • With TOF, four different problems happen in your child's heart while he is still inside the womb. The first problem is that the wall separating the two ventricles does not completely close, forming a hole. The second problem is that the blood vessel that connects the heart to the lungs is narrowed. The third problem is that the aorta (major artery) abnormally grows from both ventricles, rather than from the left ventricle only. The fourth problem is that the increased backflow of blood causes the muscles of the right ventricle to enlarge and thicken. These four defects may lead to decreased blood flow to the lungs and weakening of the heart. These problems may make it difficult for the heart and lungs to supply oxygen to your child's body.

What causes tetralogy of Fallot?

It is not exactly known what causes TOF. Caregivers think that problems during the development of your child's heart may cause TOF. The following are possible factors or conditions which may increase your child's risk of having TOF:

  • The expectant mother drinking too much alcohol while pregnant. Alcohol is found in beer, wine, liquor, such as vodka and whiskey, or other adult drinks.

  • Family history of congenital heart problems.

  • The expectant mother having a viral (germ) infection or taking medicines, such as those used for seizures (convulsions), during her pregnancy.

  • If your child has other congenital conditions, such as Down syndrome.

  • Problems with your child's genes. A gene is a little piece of information that tells the body what to do or what to make.

What are the signs and symptoms of tetralogy of Fallot?

Signs and symptoms of TOF may be present shortly after birth, during infancy, or later in childhood. The most common sign is cyanosis, where your child will have bluish-colored skin, lips, and nail beds. Your child may have tetralogy (tet) spells, where he may suddenly turn blue especially when crying or feeding. He may often squat or place his knees on his chest when he is tired. Other signs and symptoms may include any of the following:

  • Clubbing of fingertips and nails (large and bulb-like appearance).

  • Fainting (passing out).

  • Heart murmurs (abnormal changes in the heart sounds).

  • More irritable or fussy.

  • Poor appetite, slow growth, or problems putting on weight.

  • Tires easily or feels tired more than the usual.

  • Troubled breathing, such as deep and rapid breathing when eating or crying.

How is tetralogy of Fallot diagnosed?

Your child may need any of the following tests:

  • Blood tests: Your child may need blood tests to give caregivers information about how his body is working. The blood may be taken from your child's arm, hand, finger, foot, heel, or IV.

  • Cardiac catheterization: A cardiac catheterization is a test to see how well your child's heart is working. It is also used to see how well the blood vessels connected to the heart are doing. A special tube is threaded into your child's heart through a blood vessel in his arm, leg, or neck. Dye may be given so x-ray pictures of your child's blood vessels show up better on a TV-like screen. Your child's caregiver may also measure the pressure inside your child's heart.

  • Chest x-ray: This is a picture of your child's lungs and heart. A chest x-ray may be used to check your child's heart, lungs, and chest wall. It can help caregivers diagnose your child's symptoms, or suggest or monitor treatment for medical conditions.

  • Doppler: A doppler test is done to check blood flow in the heart. A small metal disc with gel is placed on your child's chest. Caregivers may hear abnormal sounds when TOF is present.

  • An echocardiogram is a type of ultrasound. Sound waves are used to show the structure and function of your child's heart.

  • 12 Lead EKG: This test helps caregivers see your child's heart activity. It helps caregivers look for changes or problems in different areas of the heart. Sticky pads are placed on your child's chest, arms, and legs. Each pad has a wire that is hooked to a machine or TV-like screen. This machine shows a tracing of your child's heartbeat. This test takes about five to ten minutes. Your child must lie very still during the test.

How is tetralogy of Fallot treated?

Your caregiver may suggest that your child squat or hug his knees to his chest when having tet spells. He may also have any of the following:

  • Surgery: Surgery is the main treatment for TOF. This may be done by making a cut through your child's chest to correct TOF. Ask your caregiver for more information about surgery for TOF.

    • Early or temporary correction: This is usually done in smaller children to increase blood flow to the lungs for a period of time. Your child's caregiver may connect one blood vessel to another. This may allow your child to grow big enough to prepare him for a complete correction surgery.

    • Complete correction: When your child is ready for a complete surgery, the problems present with TOF are corrected. The hole in the heart ventricles is closed with a patch, and the narrowed blood vessel is widened. These surgical corrections will help blood to go into the lungs and carry more oxygen to your child's body.

  • Medicines: Your child may need any of the following to prevent further problems caused by TOF:

    • Antibiotics: Ask your child's caregiver if antibiotics may be given when your child is having his teeth cleaned. Antibiotics are medicines that kill bacteria and prevent infections. Antibiotics may also be given if your child has been exposed to someone with certain infections.

    • Heart medicine: This medicine may be given to make your child's heart beat stronger or more regularly. There are many different kinds of heart medicines. Talk with caregivers to find out what your child's medicine is and why he is taking it.
With treatment of TOF such as surgery, your child's quality of life may be improved.

Where can I find support and more information?

Accepting that your child has TOF may be hard. You, your child, and those close to you may feel scared, depressed, or angry. These are normal feelings. Talk to your child's caregivers, family, or friends about your and your child's feelings. You may also want to join a support group. This is a group of people who also have children with TOF. Contact the following for more information:

  • American Heart Association
    7272 Greenville Avenue
    Dallas , TX 75231-4596
    Phone: 1- 800 - 242-8721
    Web Address:
  • National Heart, Lung and Blood Institute
    Health Information Center
    P.O. Box 30105
    Bethesda , MD 20824-0105
    Phone: 1- 301 - 592-8573
    Web Address:

Care Agreement

You have the right to help plan your child's care. Learn about your child's health condition and how it may be treated. Discuss treatment options with your child's caregivers to decide what care you want for your child. The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

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