Pharmacologic prophylaxis of postoperative atrial fibrillation in patients undergoing cardiac surgery: beyond beta-blockers.

Postoperative atrial fibrillation (POAF) is a frequent complication of cardiac surgery that increases patient morbidity, length of stay, and hospital costs. A substantial body of evidence exists evaluating various pharmacologic and nonpharmacologic methods to decrease the occurrence of POAF in an effort to decrease its burden on the health care system. Evidence-based guidelines support the use of beta-blockers as standard prophylaxis of POAF in patients undergoing cardiac surgery. Traditional prophylactic therapy for POAF targets the sympathetic nervous system, refractory period, and atrial conduction. However, associations between the development of POAF and the inflammatory process, oxidative stress, and atrial remodeling have prompted the investigation of novel therapies targeting these processes. To evaluate the role of pharmacologic strategies beyond beta-blockers in the prevention of POAF, we conducted a search of the PubMed database to identify studies published from 1950-February 2009. Emphasis was placed on how these therapies could be used in patients intolerant to beta-blockers or as additive therapy in high-risk patients. We found that sufficient evidence exists to recommend the use of amiodarone, sotalol, and possibly magnesium as monotherapy in patients unable to take beta-blockers or as add-on therapy for the prevention of POAF. Currently, available evidence does not support the use of propafenone, procainamide, digoxin, thiazolidinediones, triiodothyronine, or calcium channel blockers in the prevention of POAF. Preliminary evidence suggests that dofetilide, angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins), nonsteroidal antiinflammatory drugs, corticosteroids, omega-3 fatty acids, ascorbic acid, N-acetylcysteine, and sodium nitroprusside may be effective in preventing POAF. Additional large-scale, adequately powered clinical studies are needed to determine the benefit of these agents before they can be considered for routine use.