Postoperative arrhythmias in the pediatric population remain a significant source of morbidity and mortality despite advances in surgical techniques. Although our understanding of these arrhythmias has improved, the number of therapeutic options to treat them has not increased significantly in recent years. However, in the specific case of bradyarrhythmias, the use of pacemakers has reduced morbidity and mortality significantly. Additionally, various antiarrhythmic medications, in conjunction with physiologic maneuvers when necessary, have improved our ability to treat postoperative tachyarrhythmias. The prompt recognition and proper treatment of postoperative arrhythmias can reduce morbidity and mortality for these patients.