Anatomy
Tetralogy of Fallot (TOF) consists of 4 congenital heart anomalies that exist in a single heart defect. They are a ventricular septal defect, overriding aorta, right ventricular hypertrophy and anomaly of the pulmonary artery which includes pulmonary stenosis, pulmonary atresia, or absence of the pulmonary valve. Severity of TOF, timing of surgery, and long term outcomes are significantly influenced by the associated disease of the pulmonary artery.