Incidental diagnosis of right-to-left atrial shunt by computed tomography.

The existence and direction of an atrial shunt is normally diagnosed using echocardiography. A right-to-left atrial shunt, uncovered on routine computed tomography angiography, is presented. Transthoracic echocardiography verified the atrial shunt. TTE with intravenous agitated saline revealed the appearance of microbubbles in the left side of the heart. Atrial septal defects are a common cause of congenital heart diseases in adulthood. It may remain silent for decades because of the asymptomatic nature of the disease. Right-to-left atrial shunt is uncommon in patients with ASD.