Prevention of atrial fibrillation or flutter by acebutolol after coronary bypass grafting.

Supraventricular tachyarrhythmias are common after coronary artery bypass graft surgery (CABG) and may have deleterious hemodynamic consequences. To determine if acebutolol, a cardioselective beta-blocking drug, prevents such tachyarrhythmias after CABG, 100 consecutive patients, aged 30 to 77 years (mean +/- standard deviation 53 +/- 9), were entered into a randomized, controlled study. Exclusion criteria were: contraindications to beta-blocking drugs, left ventricular aneurysm, major renal failure, history of cardiac arrhythmia and cardiac arrhythmia during the immediate postoperative period. From 36 hours after surgery until discharge (usually on the seventh day), 50 patients were given 200 mg of acebutolol (or 400 mg if weight was more than 80 kg) orally twice a day (dosage than modified to maintain a heart rate at rest between 60 and 90 beats/min). The 50 patients in the control group did not receive beta-blocking drugs after CABG. The 2 groups were comparable in angina functional class, ejection fraction, number of diseased vessels, antianginal therapy before CABG, number of bypassed vessels and duration of cardiopulmonary bypass All patients were clinically evaluated twice daily and had continuous electrocardiographic monitoring and daily electrocardiograms. A 24-hour continuous electrocardiogram was recorded in the last 20 patients.(ABSTRACT TRUNCATED AT 250 WORDS)