Overview

Tetralogy of Fallot (teh-TRAL-uh-jee of fuh-LOW) is a rare condition caused by a combination of four heart defects that are present at birth (congenital).

These defects, which affect the structure of the heart, cause oxygen-poor blood to flow out of the heart and to the rest of the body. Infants and children with tetralogy of Fallot usually have blue-tinged skin because their blood doesn't carry enough oxygen.

Tetralogy of Fallot is often diagnosed while the baby is an infant or soon after. Sometimes, depending on the severity of the defects and symptoms, tetralogy of Fallot is not detected until adulthood.

All babies who have tetralogy of Fallot need corrective surgery. People with tetralogy of Fallot need regular doctor's checkups for the rest of their life and may have activity restrictions.