[A rare case of total anomalous pulmonary venous connection to the right atrium confounding with cor triatrium].

Three-days-old newborn baby underwent ligation of the ductus arteriosus under the diagnosis of TAPVC and PDA with high flow heart failure. Her UCG showed the direct connection of common pulmonary venous chamber (CPVC) to the upper and medial portion of right atrium. CPVC positioned just above the left atrium but does not communicated with the left atrium. These findings characterized this anomaly as II A cor triatriatum classified by Lucus-Schumidt. At 5-month-old, corrective operation was performed. Both right and left venous chambers joined just before the connection to right atrium and drained to right atrium at the upper portion of atrial septum. CPVC and left atrium had independent wall. Accordingly, operative diagnosis was made as TAPVC (IIb). Intraatrial routing was performed using porcine pericardial patch. At 6 months after operation, patient is doing well without the sign of venous obstruction. This type of TAPVC is rare and may confound with cor triatriatum. Our case may suggest the pathological mechanism of cor triatriatum and that at least some of cor triatriatum may be identical with TAPVC.