How is Tetralogy of Fallot diagnosed?


Tetralogy of Fallot is diagnosed by echocardiography. Diagnosis may occur just after birth when a heart murmur or low oxygen levels are found in a newborn.

However, many babies are now diagnosed with tetralogy of Fallot even before birth. Standard ultrasound imaging of the baby’s heart can detect TOF by 18 - 20 weeks, when the heart is large enough to be easily seen. A pediatric cardiologist can confirm the diagnosis with a fetal echocardiogram.

Additional tests may be done after birth to help determine your baby’s treatment:

  • EKG - While no longer used to determine a diagnosis, an EKG can be ordered for babies with rhythm problems associated with TOF
  • Chest X-ray - This test is rarely used to make the diagnosis, though the “boot-shaped” heart shadow on the X-ray can suggest the diagnosis of TOF and lead to further testing
  • Cardiac catheterization - A more invasive test in which thin, flexible tubes travel through the blood vessels of the baby’s leg to take pictures and measure blood pressures in the different chambers of the heart
  • MRI -In some cases of TOF, an MRI may provide important information about your child’s anatomy

How is Tetralogy of Fallot Treated?


Tetralogy of Fallot treatment involves open heart surgery, typically performed by a pediatric heart surgeon. The timing of the surgery depends on the health of the baby—most importantly, the oxygen levels in the baby’s blood.

If the baby is sick enough after birth, the surgery will be done before the baby goes home from the hospital. If the baby is doing well, the surgery can be delayed until they grow bigger. The procedure is typically done before children are 6 months old.

The complete repair of tetralogy of Fallot involves surgically removing the muscle that’s blocking the pathway to the lungs and placing a patch to close the VSD.  After tetralogy of Fallot surgery, the baby’s circulation and oxygen levels will return to normal.

Intracardiac repair

This form of open-heart surgery is usually done in the first year of life. A surgeon may use a patch to close the hole between the heart ventricles (lower chambers) or widen the right ventricle by removing excess muscle.

After surgery, the right ventricle will return to its normal size, which will increase oxygen levels in the blood and reduce TOF symptoms.

Temporary shunt surgery

Babies born with additional non-cardiac medical issues might not be well enough to tolerate a complete repair. They can have a less serious surgery for tetralogy of Fallot called a “shunt,” which provides an alternate pathway to get additional blood to the lungs and raise oxygen levels. Later, the shunt will be removed when the complete repair is done.

Post-surgical complications and care

The survival rate for infants with tetralogy of Fallot surgery is estimated at 97%. Most babies who undergo the procedure go on to lead active, healthy lives.

Here are some things parents can expect after tetralogy of Fallot repair surgery:

  • Your child may initially sleep more or feel tired
  • Tetralogy of Fallot medications can include antibiotics after surgery and heart medications in the future if other issues, such as arrhythmias, arise
  • Your child may need to take antibiotics into adulthood before certain types of surgeries and dental procedures to help prevent infection
  • Limiting exercise, especially if your child has irregular heart rhythms or blockage or leakage of the pulmonary valve
  • In some cases, blood flow to the lungs may still be obstructed. In other cases, the valves on the right side of the heart may leak. These issues may require additional surgery.
  • Arrhythmias (irregular heart rhythms) can develop after tetralogy of Fallot repair surgery. Medications, an ablation procedure, or a pacemaker may be recommended by your doctor.
  • In rare instances, some children may have a leaky or insufficient pulmonary valve that needs to be replaced
  • Continuous care into adulthood. Infants diagnosed and treated for tetralogy of Fallot will require life-long attention from a congenital cardiologist for routine testing and heart-health maintenance.
Get Care

Trust NewYork-Presbyterian for Tetralogy of Fallot Treatment

NewYork-Presbyterian is one of the world’s top providers of cardiovascular care for children and adults. We specialize in a range of congenital heart diseases, including TOF, pulmonary stenosis, hypertrophy of the right ventricle, ventricular septal defects (VSD), an overriding aorta, and patent foramen ovale (PFO).

We recognize the symptoms of tetralogy of Fallot and the anxiety it causes parents. Our compassionate, multidisciplinary teams of cardiac specialists are here to care for you and your baby’s heart. Contact NewYork-Presbyterian for the best in cardiac treatment options.