Objectives This study described and analysed the termination of persistent atrial fibrillation (AF) by an intravenous bolus of common dosage midazolam in patients who underwent extensive catheter ablation.
Methods Radiofrequency catheter ablation was performed in 210 consecutive persistent AF patients (156 males, mean age 58.1±10.5 years), who under sedation with a bolus of midazolam and analgesia with a continuous infusion of fentanyl. An intravenous bolus of midazolam was used for inducing sedation for electrical cardioversion in patients whose atrial arrhythmias were not terminated by ablation.
Results After extensive ablation, inducing sedation for electrical cardioversion was attempted in 99 patients (47.1%, 74 males, meanage 57.9±10.3 years). Termination of atrial arrhythmias and restoration of sinus rhythm were observed in five patients (5.1%, all male, mean age 53.0±9.9 years old), 16.0±4.2 s after the administration of midazolam (1–2 mg) without antiarrhythmics or electrical cardioversion. Two patients encountered the recurrence of atrial flutter (AFL), and one of them had a second ablation. During 32.8±16.7 months post the last procedure, 4 (80%) patients were free of arrhythmias without the use of antiarrhythmics and one patient remained in drug-refractory persistent AFL.
Conclusions In patients who underwent extensive ablation for persistent AF, an intravenousbolus of common dosage midazolam may have the cardioversion effectiveness.