Ibutilide is efficacy but not safe in cardioversion of atrial fibrillation for patients aged over 75 years

Abstract

Background: Atrial fibrillation (AF) is the common arrhythmia resulting in high morbidity and mortality. Ibutilide is used to convert AF to sinus rhythm pharmacologically. We aimed to evaluate the clinical efficacy and safety of ibutilide for patients over 75 years old with recent onset AF.Methods: 81 patients over 75 years old with recent onset AF less than 72 hours, range from 75 to 85 years, were analyzed retrospectively from January 2015 to January 2019. 40 patients received ibutilide, and another 41 patients received propafenone as the control group. In ibutilide group, patients weighing over 60 kg were received 1 mg of ibutilide, and ibutilide at 0.01 mg / kg were administrated when the patient’s body weight was less than 60 kg. If cardioversion failed, 1 mg or 0.01 mg/kg of ibutilide would be given after 10 minutes. In control group, patients were received propafenone at 75mg. If there was no effect on cardioversion, 35 mg of propafenone would be given after 10 minutes.Results: In control group 26 patients (63.4%) converted to sinus rhythm, and in ibutilide group, 35(87.5%) converted to sinus rhythm (p<0.05, vs control group). The converting time of ibutilide group was shorter than control group(13.5±9.27s vs 43.72±10.27s,P<0.05 ). The corrected QT (QTc) intervals was significantly prolonged in patients after the administration of ibutilide(P<0.05). In ibutilide group, five patients (12.5%) appeared torsades de pointes (TdP) and converted to sinus rhythm via electrical cardioversion. Six patients (14.6%) developed severe bradycardia in control group, and the bradycardia alleviated after discontinuation of propafenone. Nine patients (21.9%) who failed in cardioversion with 24 hours by propafenone converted to sinus rhythm via electrical cardioversion.Conclusion: Ibutilide could effectively convert recent onset (<72 hours) AF in patients aged over 75 years. However, it was worth noting that the high rate of TdP emerged in these elderly patients after the treatment of ibutilide.