Efficacy of intravenous propafenone in acute atrial fibrillation complicating open-heart surgery.

Early postoperative atrial fibrillation (AF) is a frequent complication of major cardiovascular surgery. To assess the effectiveness of intravenous propafenone in this setting, we studied 50 patients who developed AF within 48 hours after open-heart surgery. Intravenous propafenone (2 mg/kg in 10 minutes) was administered 15 minutes after the onset of the arrhythmia. Sinus rhythm was restored in 35 patients (70%) after a mean time of 22 +/- 6 minutes after the beginning of the infusion. The conversion was obtained in 28 of 32 patients (88%) who had a coronary artery bypass graft and in 7 of 18 patients (39%) who had valvular or septal surgery (p less than 0.01). In those whose arrhythmia did not convert to sinus rhythm, the ventricular rate was reduced from 142 +/- 14 beats/min to 108 +/- 9 beats/min (p less than 0.01). In patients whose arrhythmia was converted to sinus rhythm, mean cardiac index increased from a mean baseline value of 2.7 +/- 0.4 L/min/m2 to 3.4 +/- 0.1 L/min/m2 (p less than 0.05), while it remained virtually unchanged in those whose arrhythmia did not convert. No significant side effects were observed. We conclude that intravenous propafenone is effective in converting to sinus rhythm the majority of patients with AF complicating open-heart surgery. Heart rate was reduced in those who did not convert to sinus rhythm and no side effects nor hemodynamic deterioration were observed in any case.