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Symptoms of Tetralogy of Fallot

The main effect of tetralogy of Fallot is that there’s not as much oxygen in the baby’s blood as there should be. A low oxygen level can make the baby’s skin, lips and fingernails look blue. This is called cyanosis.

Cyanosis can range from mild to severe, depending on how much oxygen-poor (blue) blood makes it to their lungs and how much goes out to their body. Some babies with this condition do not appear bluish at birth. They may become cyanotic later as their pulmonary stenosis gets worse.

Your baby may also have trouble feeding and failure to thrive.

Some babies with tetralogy of Fallot have episodes called Tet spells, when they suddenly turn bluish and may faint. These spells are serious. Your doctor will talk with you about what do to if this happens to your child.

A Tet spell may be triggered by activities that change the pressure in the heart and increase flow of oxygen-poor blood to the body. This may include crying, moving the bowels or kicking the legs after waking up. Tet spells occur most often in babies between 2 and 4 months of age.

Tetralogy of Fallot Diagnosis

To diagnose this condition, your doctor will examine your child and use a stethoscope to listen to their heart. In children with tetralogy of Fallot, doctors almost always hear a heart murmur — the sound of blood moving in the heart in a way that’s not normal.

The doctor will ask for details about your child’s symptoms, their health history and your family health history.

Your child will also need tests that provide information about how their heart looks and works. These may include blood tests, a chest X-rays or MRI (magnetic resonance imaging) of the heart, echocardiographyelectrocardiogram and sometimes cardiac catheterization.

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Summer 2014: Good Growing Newsletter

In This Issue

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Download Summer 2014 (PDF)