The diagnosis of cor triatriatum sinistrum in children: a continuing dilemma.

Cor triatriatum (CT) is a rare congenital cardiac anomaly. The salient clinical, roentgenographic, electrocardiographic, echocardiographic, and hemodynamic findings are presented in two asymptomatic children and one with nonspecific dyspnea on exertion. Two male children had a classical form of cor triatriatum with normal physical and inconsequential roentgenographic and electrocardiographic findings. One of the male patients had surgery for a large atrial septal defect ostium secundum (ASD 2 degrees) and pulmonary hypertension in infancy. The female patient had CT with a communicating accessory chamber to right atrium and a rare patent foramen ovale. Her clinical findings confirmed an atrial level shunt. All patients had excision of the fibromuscular membrane from the right and left atrial transseptal approach with excellent results and with no recurrence during 2 to 4 year follow-up. We report the dilemma encountered in the clinical diagnosis of CT in children and the pivotal role played by echocardiography in the diagnosis of this anomaly.