Ibutilide is a type III antiarrhythmic agent for the pharmacological conversion of atrial fibrillation (AF) and flutter (AFl). Previous studies conducted outside the Emergency Department (ED) setting have demonstrated conversion rates of 60 to 80%. This response has been highest in patients with recent onset AF. These observations and Ibutilide’s 6-hour half-life, suggest that it may be an excellent drug with which to treat AF-AFl in the ED. The purpose of this study was to examine Ibutilide’s efficacy in terminating AF-AFl in patients who present to the ED with symptoms of < 3 days’ duration, neither angina nor heart failure and no co-morbid condition that required admission.
Ibutilide 1mg was administered intravenously over 10 minutes. If normal sinus rhythm (NSR) was not present 10 minutes after its conclusion, a second dose of 1mg was infused. Successful conversion was defined as restoration of NSR within 1 hour after the last dose of ibutilide. All patients underwent echocardiography and were monitored > 3 hours after Ibutilide infusion was completed.
Among 36 enrolled patients (22 men, mean age 68 + 12 years) the admission ECG demonstrated AF in 26 and AFl in 10. Serum TSH was normal in all. Mean symptom duration was 11 + 6 hours. All patients demonstrated normal LV function without hypertrophy. Sixteen (62%) of 26 patients with AF and 9 (90%) of 10 with AFl converted to NSR (overall conversion rate = 69%). The mean time to conversion was 19  9 minutes. The mean ED stay was 16.2  7.4 hours. No complications were observed.
Ibutilide safely and rapidly converts AF and AFl of < 3 days’ duration in the majority of patients who present without symptoms of angina or heart failure without the need to delay care to prepare for electrical cardioversion, administer anesthesia or admit patients for telemetry monitoring.
We recommend Ibutilide therapy in the ED to treat healthy patients with recent onset atrial fibrillation - flutter.
S. Mountantonakis, None.