Hybrid therapy with right atrial catheter ablation and previously ineffective antiarrhythmic drugs for the management of atrial fibrillation

Background: Many patients with paroxysmal atrial fibrillation (AF) become refractory to antiarrhythmic drugs (AADs). Early studies suggested that linear catheter ablation in the right atrium may provide sufficient substrate modification to reestablish therapeutic efficacy of previously ineffective AADs. Methods: This prospective before-after multicenter trial evaluated the safety and effectiveness of hybrid therapy that included right atrial catheter ablation coupled with a regimen of previously ineffective AADs on AF episode frequency and symptoms in drug refractory patients with paroxysmal AF. A standard linear lesion set (lateral, septal, isthmus) was used in all subjects. AF episode frequency, clinical arrhythmia symptoms, condition-specific (AFSS) and global health-related quality of life (SF-36) were assessed prior to ablation and at 6 months. Results: Ninety-three subjects, refractory to an average 2.9 AADs at baseline, qualified for inclusion and underwent right atrial catheter ablation. Eighty-four subjects (90%) provided 6 month AF episode frequency data which demonstrated a significant decrease compared to baseline (3.4 vs. 9.5, p < 0.0001). Forty-nine subjects (58%) were considered a clinical success by virtue of achieving a pre-specified target level episode frequency reduction of 50% or greater. Substantial and statistically significant improvements were realized almost uniformly for all measured arrhythmia symptoms as well as for both quality of life measures. The incidence of major complications was 5.4%. Conclusions: The addition of right atrial catheter ablation to a regimen of previously ineffective AADs is associated with a significant reduction in the frequency, duration and severity of AF episodes and symptoms.