Coronary Sinus Blues: A Word of Caution When Placing the Coronary Sinus Ostium in the Left Atrium.

Complications related to the coronary sinus following cardiac surgery are rare and require a high index of suspicion to ensure timely diagnosis and treatment. We describe the clinical presentation and management of a patient with atrioventricular septal defect who developed coronary sinus ostial obstruction following left atrioventricular valve replacement. This manifested as a decline in ventricular function and supraventricular arrhythmias. Surgical enlargement of the coronary sinus ostium was initially successful but failed to produce a durable result.Meeting presentation: Oral presentation at the Congenital Heart Surgeons' Society Annual Meeting; October 19, 2023; Boston, MA.