The incidence of postoperative atrial fibrillation in cardiac surgery is still high despite major advances in anesthetic, pharmacological and surgical techniques. Its precise mechanism is still totally unknown. Postoperative atrial fibrillation increases length of stay as well as hospital costs. Rate of postoperative atrial fibrillation spontaneous conversion is high. Several protocols have been developed for prevention and/or treatment of postoperative atrial fibrillation. Beta-blockers, amiodarone and atrial pacing reduce.atrial fibrillation incidence as compared to placebo. On the other hand, amiodarone and propafenone achieve a high conversion rate of installed postoperative atrial fibrillation. However, among many pharmacological options, the best treatment is still to be defined.