What is "tetralogy of fallot"

n. a congenital heart defect producing cyanosis; characterized by four symptoms: pulmonary stenosis and ventricular septal defect and malposition of the aorta over both ventricles and hypertrophy of the right ventricle [syn: Fallot's tetralogy, Fallot's syndrome]

Tetralogy of Fallot (TOF) is a congenital heart defect which is classically understood to involve four anatomical abnormalities of the heart (although only three of them are always present). It is the most common cyanotic heart defect and the most common cause of blue baby syndrome. TOF is usually a right-to-left shunt, in which higher resistance to right ventricular outflow results in more severe cyanosis symptoms.

TOF is treated with corrective surgery, usually within the first year of life, but presents with long-term problems including arrhythmia, pulmonary regurgitation, and re-operation.

In the United States, the prevalence of TOF is 3.9 per 10,000 live births and accounts for 7-10% of congenital heart diseases. It was described in 1672 by Niels Stensen, in 1773 by Edward Sandifort, and in 1888 by the French physician Étienne-Louis Arthur Fallot, after whom it is named.