European prospective multicentre study of hybrid thoracoscopic and transcatheter ablation of persistent atrial fibrillation: The HISTORIC-AF trial

OBJECTIVES: The HISTORIC-AF trial is a prospective, multicentre, single-arm study designed to evaluate the outcomes of a staged endoscopic and transcatheter ablation in patients with stand-alone, persistent or long-standing persistent atrial fibrillation (AF). METHODS: From 2012 to 2015, 100 consecutive patients were enrolled and underwent thoracoscopic left atrial epicardial isolation ('box lesion') followed by transcatheter ablation in case of AF recurrency. The safety end point was the composite outcome of freedom from major adverse events at 30-days, while efficacy end points were: (i) primary: freedom from AF and stable sinus rhythm following isolated thoracospic ablation > 60% and (ii) secondary: freedom from AF and stable sinus rhythm > 80% following hybrid ablation (as per HRS criteria). RESULTS: No death occurred and surgical thoracoscopic procedure was successfully completed in all patients. Survival free from major adverse events at 30 days was 94%: there were 3 permanent pacemaker implants, 2 episodes of stroke and 1 revision for bleeding. At discharge, 87% of patients were in sinus rhythm. A staged transcatheter ablation was carried out in all patients with AF recurrences at the end of 3 months blanking period (17% of patients). At 12-months follow-up, a stable restoration of sinus rhythm was achieved in 75% and 88% of patients following isolated thoracoscopic ablation and hybrid ablation, respectively. CONCLUSIONS: The HISTORIC-AF trial showed that thoracoscopic isolated surgical ablation reached both the safety and the efficacy end points. Hybrid ablation steadily improved rhythm outcomes and may be considered in the future as the treatment of choice for patients with persistent and long-standing persistent AF.