We report two cases with persistence of the hepatic venous complex, underdevelopment of the inferior caval vein and azygos continuation to the superior caval vein. We suggest that the hepatic venous complex is a true congenital malformation rather than the result of passive enlargement of venous channels subsequent to high venous pressures. Preoperative diagnosis is important in patients with complex congenital heart disease undergoing palliative venous redirection procedures if a postoperative right-to-left shunt and cyanosis are to be avoided.
