Statin therapy may influence the incidence of postoperative atrial fibrillation: what is the evidence?

Atrial fibrillation is the most common postoperative arrhythmia in patients who undergo cardiac surgery. We sought to determine whether the administration of statins reduces the incidence of postoperative atrial fibrillation in cardiac surgery patients. We performed a meta-analysis on all studies published between 2004 and 2008 that reported comparisons between statin treatment or nontreatment in these patients. Our primary focus was the incidence of postoperative atrial fibrillation. Random-effects modeling and sensitivity analysis were used to evaluate the consistency of the calculated treatment effect. Ten qualifying studies generated a total of 4,459 patients. The incidence of postoperative atrial fibrillation was 22.6% (622/2,758) in the statin-treated group and 29.8% (507/1,701) in the untreated group. Using the random-effects model, we calculated an odds ratio (OR) of 0.60 (95% confidence interval [CI], 0.48-0.76). When we considered only the 4 randomized studies (919 patients) in order to reduce the effects of heterogeneity, this significant reduction in the incidence of postoperative atrial fibrillation in the statin group was maintained (OR, 0.55; 95% CI, 0.41-0.73) with no heterogeneity (chi2 of heterogeneity, 2.96; P = 0.4). In studies wherein only coronary artery bypass grafting was performed, statin treatment decreased postoperative atrial fibrillation (OR, 0.64; 95% CI, 0.43-0.95). We conclude that statin administration results in a reduction in the incidence of atrial fibrillation in patients who undergo cardiac surgery. Further research into the underlying mechanism can elucidate possible relationships between the dosage and type of statin used.