What is Fontan operation?

Fontan operation is an operation used for treatment of certain birth defects of the heart like tricuspid atresia. In tricuspid atresia there is no opening for the tricuspid valve. Tricuspid valve is the valve between the right upper and lower chambers of the heart. It guards the opening from the right atrium to the right ventricle and prevents backflow of blood when the right ventricle contracts. When there is tricuspid atresia, blood reaches the left atrium through a defect in the wall between the two, which is mandatory for survival in such cases.