Intraoperative 2D and 3D transesophageal echocardiographic assessment of cor triatriatum with ostium secundum atrial septal defect in an adult patient

Cor triatriatum is a rare congenital cardiac anomaly. Majority of the cases present in the childhood with an incidence of 0.4%. However, we report a case of cor triatrium sinister with ostium secundum atrial septal defect (ASD) in a 39-year-old female. The intraoperative 3D transesophageal echocardiography (TEE) offers an advantage over 2D TEE in visualizing the interatrial septum and the attachments of the fibromuscular accessory membrane in the left atrium (LA), which could help in surgical decision-making in this patient.