Echocardiographic Discovery of Doubled Interatrial Septum: An Incidental Finding

A double-walled interatrial septum is a rare congenital cardiac anomaly characterized by a distinct echolucent cavity between the atria formed by 2 separate interatrial septae. It may be a variant of other well-recognized cardiac anomalies such as persistent venous valve of the sinus venosus or cor triatriatum. Although uncommon, it may be associated with thromboembolic disease due to stagnant flow in the septal cavity. Awareness of this rare entity and its clinical significance along with a thorough echocardiographic examination to rule out similarly presenting or coexisting conditions are the key to an accurate diagnosis and appropriate management.