Anomalous connection of the inferior vena cava to the left atrium: a surgical error in closing an atrial septal defect

The diagnosis of surgical error in closing an atrial septal detect using the Eustachian valve, a remnant of the right valve of the sinus venosus, protecting the upper and anterior end of the inferior vena cava (IVC), is presented. Misconnecting the IVC to the left atrium is a dangerous situation for the patient. It creates arterial desaturation, and provides a way for paradoxical embolism. The Eustachian valve can direct the caval inflow away from the tricuspid valve toward any interatrial septal opening, causing arterial desaturation. Surgical misplacement can lead to residual defects with a right to left shunt and arterial desaturation. A surgeon needs to use appropriate Eustachian valve to connect the IVC to the the left atrium with the superior vena cava supplying the residual right atrium and right ventricle.