Atrial fibrillation in patients undergoing surgical revascularization: an update on pharmacologic prophylaxis

Atrial fibrillation occurs in 20-50% of patients after surgical revascularization (40% have more than 1 episode), with a peak between 2nd and 3rd postoperative days. Postoperative atrial fibrillation (POAF) has been associated with an increase in adverse events, length of hospital stay and, therefore, cost of care, and late mortality. A higher risk profile in patients who develop POAF may contribute to the higher late mortality rate. The pathogenesis of PAOF is multi factorial: transient ischemia during surgical procedure, neurohormonal activation, electrolyte imbalance, fluid overload and finally an exaggerated inflammatory response have been associated with POAF. Advanced age, an history of AF or heart failure and, finally, COPD are clinically independent risk factors related to POAF. The lower incidence of POAF reported after off-pump CABG in comparison to conventional cardiopulmonary by-pass CABG techniques has not been confirmed. The administration of antiarrhythmic drugs (amiodarone, metoprolol, sotalol and recently propafenone and landiolol) before and /or after surgical procedure has been extensively investigated and most of the investigators have demonstrated a favorable effect on POAF incidence. The decreased incidence of POAF and related shorter hospital stay by PUFA administration during hospitalization needs to be confirmed. Preliminary results suggest that pre-treatment with the antianginal drug ranolazine may significantly decrease POAF incidence. Treatments directed to antagonize inflammation are presently under investigation. Recently, a randomized study with naproxen, although effective on POAF, was interrupted due to increased risk of nephrotoxicty. Despite different action mechanisms, both hydrocortisone and statins have been shown to decrease post-operative AF risk. No data at present exist on the effects of association of these drugs. Aim of the present review was to update the current practice and report the recent results of research in the prophylaxis of atrial fibrillation in patients undergoing CABG.