Atresia of coronary sinus ostium with retrograde drainage via persistent left superior vena cava.

Atesia of the coronary sinus ostium (ACSO) with retrograde drainage of cardiac veins via the left superior vena cava (LSVC) is a very rare abnormality. This condition is usually asymptomatic during life and a majority of the cases were reported as incidental postmortem findings. If there is retrograde venous drainage via persistent LSVC, this communication cannot be ligated irrespective of its size or the presence of a communicating vein because of resultant cardiac congestion and edema. We report herein a 9-month-old Chinese female who underwent repair of a perimembranous ventricular septal defect, patent ductus arteriosus and secundum atrial septal defect. During the operation, ligation of LSVC resulted in myocardial congestion and distension of the heart. The release of ligature decompressed the heart immediately.