The Effects of Ibutilide and Amiodarone on Tpeak-End/QT Ratio for the Treatment of Atrial Fibrillation / 天津医药

ABSTRACT

Objective To investigate the effects of ibutilide and amiodarone on the ventricular transmural heteroge-neity of repolarization and ventricular arrhythmia for the treatment of atrial fibrillation. Methods Eighty-seven patients with paroxymal atrial fibrillation at 48 h~7 d were enrolled and randomized to two groups, ibutilide and amiodarone treat-ment groups. The successful rate of cardioversion to sinus rhythm was compared between two groups. The electrocardiograph-ic QT interval and Tpeak-end/QT ratio were also analyzed before and after treatment in two groups. Results The successful rate of cardioversion was significantly higher in ibutilide group than that of amiodarone group (61.7%vs 40.7%, P＜0.05). The QT intervals and Tpeak-end/QT ratio were both significantly increased in ibutilide group (P＜0.05), which were re-turned to the levels before treatment in 2 hours and 1 hour, respectively (P＜0.05). The QT intervals were significantly in-creased in the amiodarone group (P＜0.01), which were continued until 4 h after treatment. There were no significant differ-ences in the Tpeak-end/QT ratios before and after treatment (P>0.05). Conclusion The successful rate of cardioversion to sinus rhythm for atrial fibrillation by ibutilide was significantly higher compared with that of amiodarone. Ibutilide slightly in-creased the transmural heterogeneity of repolarization within the first hour, which may increase the risk of ventricular arrhyth-mia.