What characterizes tricuspid atresia?

Tricuspid atresia is characterized by the absence of the tricuspid valve, which leads to an underdeveloped or hypoplastic right ventricle. In this condition, blood from the right atrium cannot flow into the right ventricle as it normally would, since the tricuspid valve is not present. Instead, the blood must flow through a combination of other structures, typically involving the foramen ovale or a shunt, to reach the lungs for oxygenation. This absence of the valve and the corresponding underdevelopment of the right ventricle are hallmark features that distinguish tricuspid atresia from other congenital heart defects. The combination of these abnormalities significantly impacts the heart's ability to pump blood effectively, contributing to the clinical presentation of this condition.