Clinical research on intravenous ibutilide versus propafenone for immediate cardioversion of recent-onset atrial fibrillation

Objective To compare the efficacy and safety of intravenous ibutilide versus propafenone for immediate cardioversion of recent-onset atrial fibrillation.Methods Sixty-nine consecutive patients with atrial fibrillation (onset within 1.5 h～89 d) were randomly and single-blinded assigned to two groups:the ibutilide group(n=34) and the propafenone group(n=35).Patients in the ibutilide group received ibutilide 1 mg IV over 10 min.Patients in propafenone group received propafenone 70 mg IV over 10 min.If atrial fibrillation persisted ten minutes later,repeat the first loading.Results The rate of cardioversion of the ibutilide group is significantly higher than that of propafenone group for up to 1.5 h (70.59% vs 42.86%,P0.05).The conversion rate was higher in patients whose atrial fibrillation had persisted within 24 h than that over 24 h (71.05% vs 38.71% P0.01).The efficacy was higher in patients whose left atrial diameter was below 4.0 cm than that over 4.0 cm (75.68% vs 34.38%,P0.01).The most serious adverse effect of ibutilide was nonsustained monomorphic ventricular tachycardia (8.82%),which was associated with ibutilide within 5～90 min after starting the infusion.Hypotension (2.86%) and heart pause (RR interval2.0 s,11.43%) were the most serious adverse events in patients who received propafenone.Conclusion Intravenous ibutilide is a safe and effective agent for cardioversion of recent-onset atrial fibrillation.