ACE inhibitor therapy: Possible effective prevention of new-onset atrial fibrillation following cardiac surgery

Abstract

Background: Atrial fibrillation (AF) is a common complication after coronary artery bypass grafting (CABG). The aims of the study were to assess possible predictors and identify modes of prevention of new-onset AF following coronary surgery.
Methods: Retrospective clinical and statistical analysis was made of the medical records of 217 patients who had undergone coronary surgery.
Results: AF occurred in 28% (61/217) of the patients. In univariate analysis the age of the patients with AF was higher (p = 0.0033), they had a longer history of coronary disease (p = 0.0417) and more had > 3 grafts (p < 0.05). Low ejection fraction (< 40%) was also a risk factor of arrhythmia (p < 0.0001). In multivariate regression analysis two independent predictors of AF were identified: no ACE inhibitor treatment before surgery (p = 0.0005) and age > 60 years (p < 0.01). Patients with AF had a higher mean heart rate after the procedure: 115 ± 34 vs. 78 ± 21/min (p < 0.0005). Patients treated with ACE inhibitors before and after surgery had a lower incidence of AF than non-treated patients: 8% vs. 48% (p < 0.0001) and 4% vs. 61%, p < 0.0001) respectively. Beta-blocker treatment before and after surgery resulted in a lower incidence of AF: at 23% vs. 75% (p < 0.001) and 19% vs. 96% (p < 0.0001), respectively.
Conclusions: No ACE inhibitor therapy before surgery, advanced age, low ejection fraction, high post-procedure heart rate, duration of coronary disease and the number of grafts (corresponding to the length of the procedure) were found to be strong probable predictors of AF following cardiac surgery. ACE inhibitor therapy may be effective in the prevention of newonset AF. Treatment based on individual variables is crucial for proper treatment and to diminish the risk of arrhythmia. (Cardiol J 2007; 14: 274-280)