What Happens If Hepatic Veins Drain to the Pulmonary Venous Atrium?

In rare instances in congenital cardiac surgery, ≥1 of the hepatic veins may end up incorporated either intentionally or inadvertently with the pulmonary venous atrium (oxygenated blood) while the remainder of the hepatic veins are left to drain normally with the systemic venous blood (less oxygenated blood). What happens when this is done? As it turns out, hepatic venous connections end up forming between the lobes of the liver, and a significant shunt results. The direction of shunting, however, depends on the physiology. We present 2 cases in which a single hepatic vein was left connected to the pulmonary venous atrium and produced very different hemodynamic consequences.