Tetralogy of Fallot (TOF)

What is tetralogy of Fallot?

Tetralogy of Fallot (TOF) is a serious congenital heart defect affecting about two in 10,000 babies. In TOF, a set of four abnormalities in the heart’s anatomy prevent enough oxygen-poor (blue) blood from flowing to the lungs to receive oxygen. As a result, people with TOF have a lower than normal amount of oxygen in their blood and will typically need surgery to correct the flow. Infants born with TOF were once called “blue babies.”