The effect of a high dose of atorvastatin on the occurrence of atrial fibrillation after coronary artery bypass grafting.

BACKGROUND: Recent studies have suggested that statins reduce the incidence of atrial fibrillation (AF) after cardiac operations. Statin therapy at intensive doses, however, has yet to be thoroughly investigated. METHODS: We retrospectively studied 1,839 consecutive patients (1,177 men [73.2%]) who underwent isolated coronary artery bypass grafting and had no history of previous AF, pacemaker implantation, or antiarrhythmic medication. Data recorded included the atorvastatin dose during hospitalization, demographic, echocardiographic, and angiographic data, medical history, drug treatment, and procedural characteristics. Continuous telemonitoring during the first 72 postoperative hours assessed for AF, which was defined as episodes lasting more than 5 minutes. The dose-related effect of atorvastatin on postoperative AF was investigated by logistic analysis in 1,607 patients: 75 (4.7%) did not receive atorvastatin vs 1,047 (65.1%) and 485 (30.2%) who received 40 mg/d or 80 mg/d, respectively, for at least 3 days before the operation. RESULTS: The study population was a mean age of 60.6 ± 9.5 years. Multivariate logistic regression demonstrated that a lack of atorvastatin pretreatment along with older age, enlarged left atrium, and male sex, and not taking ß-blockers, tended to be associated with an increased risk of postoperative AF. There was no significant difference between the effect of a higher (80 mg/d) and a lower dose (40 mg/d) in reducing postoperative AF. CONCLUSIONS: Atorvastatin pretreatment significantly reduced the occurrence of AF after bypass grafting; nonetheless, the difference between the beneficial effects of intensive and routine atorvastatin treatments on postoperative AF was not significant.