A single bolus of intravenous dofetilide (8 mcg/kg) terminated sustained atrial fibrillation or flutter in 31% of patients compared to 0% with placebo (p < 0.01).
RCT (n=91)
Double-blind
randomized
Yes
Does a single bolus of intravenous dofetilide improve the termination of sustained atrial fibrillation or flutter in patients with these arrhythmias?
Intravenous dofetilide is effective for the acute termination of sustained atrial fibrillation and flutter, with particularly high efficacy in atrial flutter.
Absolute Event Rate: 31% vs 0%
p-value: p=< 0.01
OBJECTIVES: This study sought to determine the safety and efficacy of a single bolus of intravenous dofetilide, a pure class III antiarrhythmic agent, for the termination of sustained atrial fibrillation or flutter. BACKGROUND: Dofetilide is a highly selective blocker of the rapid component of the delayed rectifier current causing action potential prolongation. These effects, and preliminary clinical data, suggest that it may be effective in the treatment of atrial fibrillation and flutter. METHODS: Ninety-one patients with sustained atrial fibrillation (75 patients) or flutter (16 patients) were entered into a double-blind, randomized multicenter study of one of two doses of dofetilide (4 or 8 micrograms/kg body weight) or placebo. RESULTS: Dofetilide effectively terminated the arrhythmia in 31% of patients receiving 8 micrograms/kg, a statistically significant difference from those receiving 4 micrograms/kg (conversion rate 12.5%, p < 0.05) or placebo (no conversion, p < 0.01). Patients with atrial flutter had a greater response to dofetilide (54% conversion rate) than those with atrial fibrillation (14.5% conversion rate, p < 0.001). CONCLUSIONS: Intravenous dofetilide can convert sustained atrial fibrillation or flutter to sinus rhythm. However, its efficacy is greater in flutter--a response that contrasts with the poorer response seen with class I agents. This finding potentially represents an important advance in the pharmacologic termination of atrial flutter.
Falk et al. (1997) conducted an RCT in Sustained atrial fibrillation or flutter (n=91). Intravenous dofetilide vs. Placebo was evaluated on Termination of sustained atrial fibrillation or flutter (p=< 0.01). A single bolus of intravenous dofetilide (8 mcg/kg) terminated sustained atrial fibrillation or flutter in 31% of patients compared to 0% with placebo (p < 0.01).