Cardiac complication following the surgical closure of a secundum atrial septal defect (ASD) is extremely uncommon in the current era. We report a case of 39-year-old male presented with hemoptysis following an ASD closure 21 years prior and diagnosed to have iatrogenic closure of the coronary sinus at the time of surgical ASD closure. To our best knowledge, this is the first case of such complication reported in the literature.