Rare coexistence of unroofed coronary sinus, coronary sinus atresia and rheumatic mitral stenosis demonstrated by multimodality imaging.

Unroofed coronary sinus (CS) with CS orifice atresia and persistent left superior vena cava (PLSVC) is an exceptionally rare congenital anomaly that may coexist with acquired valvular disease, as illustrated in this case of severe rheumatic mitral stenosis. Multimodality imaging including echocardiography and cardiac CT was essential for precise anatomical delineation, guiding safe surgical intervention. Recognition of this complex anatomy is critical to avoid catastrophic complications such as inadvertent PLSVC ligation without ensuring adequate CS drainage. This case highlights the importance of comprehensive preoperative imaging in managing combined congenital and acquired cardiac pathologies.