Tricuspid atresia with atrial septal defect (ASD)

Tricuspid atresia is a birth defect of the tricuspid valve, which is the valve that controls blood flow from the right atrium (upper right chamber of the heart) to the right ventricle (lower right chamber of the heart). Tricuspid atresia occurs when this valve doesn’t form at all, and no blood can go from the right atrium through the right ventricle to the lungs for oxygen. Because a baby with tricuspid atresia may need surgery or other procedures soon after birth, this birth defect is considered a critical congenital heart defect. Congenital means present at birth.