Aim: Atrial fibrillation (AF) is common after cardiac surgery, but prophylaxis for patients especially prone to developing this arrhythmia has not been studied to date. We investigated amiodarone as prophylaxis for AF in selected patients after open-heart surgery.
Methods: In the first stage we studied a group of 204 consecutive cardiac surgery patients and devised a formula from some of the known risk factors of AF for each sex to serve as a predictor model. In this first group we were able to quantify the probability of developing this arrhythmia. In the second stage we applied this formula to a group of 231 consecutive cardiac surgery patients and then selectively treated the high-risk patients for AF: 25 men (16.1%) and 29 women (53.7%). In the first 24 h of treatment with amiodarone, 22 patients (10 men and 12 women) were excluded from the study due to sinus bradycardia. Therapy consisted of amiodarone 900 mg intravenously every 24 h for the first 2 postoperative days, followed by 600 mg intravenously every 24 h until discharge from the Intensive Care Unit.
Results: Expected AF in males fell from 34.4% (52/151) in the observation group to 11% (17/155) in the treated group, and in females from 50.9% in the observation group (27/53) to 9.3% (5/54) in the treated group (P<0.001).
Conclusions: Patient-selective prophylaxis of AF with amiodarone can be a highly effective measure.