Tricuspid atresia is the third most common cyanotic congenital heart defect. It consists of complete lack of tricuspid valve formation, with no connection between the right atrium and the right ventricle. Severe cyanosis associated with diminished pulmonary blood flow is a prominent feature in tricuspid atresia. The malformation brings about high morbidity and mortality, thus requiring the utilization of an adequate surgical technique for its correction. The genetic mechanism responsible of tricuspid atresia is still obscure. However, animal models have suggested a role of cardiogenic Zfpm2/Fog2 and Hey2 genes in the pathogenesis.
