Atrial fibrillation is a frequent complication after CABG. It occurs in 20-50% of patients, most often between the 2nd and 3rd postoperative day. About 40 % of patients experience more than 1 episode. Postoperative AF (POAF) is associated with an increase in adverse events and hospital stay and, therefore, costs of care. The incidence of POAF is not influenced by the technique of CABG with or without cardiopulmonary by-pass Neurohormonal activation, electrolyte imbalance, fluid overload, surgical practices and finally an exaggerated inflammatory response has been proposed to be etiological factor. Advanced age, history of AF or heart failure, COPD, postoperative withdrawal of β -blockers are independent risk factors of postoperative AF. Conversely, postoperative administration of β-blockers, ACE inhibitors, potassium supplementation and NSAID were associated with a reduced risk of POAF. Pharmacological strategies for prevention of POAF may be divided in two main groups : the first one encompasses the use of antiarrhythmic drugs (amiodarone, metoprolol, sotalol) before and /or after surgery and has been extensively investigated in the last two decades. Recently an Italian study has shown that PUFA administration during hospitalization in patients undergoing CABG significantly decreased the incidence of POAF and was associated with a shorter hospital stay. Since an exaggerated inflammatory reaction may play a significant role in POAF, treatments directed to antagonize inflammation are presently under investigation. Despite different action mechanisms both hydrocortisone and statins have been shown to decrease postoperative AF risk. These two prophylactic regimens are not mutually exclusive and some data suggest that their association may be useful to further decrease the risk of POAF.