High-density mapping guided the modified box and driver ablation for non-paroxysmal atrial fibrillation: a retrospective single-center study

BACKGROUND: For patients with non-paroxysmal atrial fibrillation (AF), the necessity of linear ablation remains uncertain, and the benefits of posterior wall BOX isolation continue to be controversial. Recent evidence has demonstrated positive effects of driver ablation. Therefore, we designed a novel strategy termed modified posterior wall BOX isolation (m-BOX, roof line and inferior line along coronary sinus projection to connect pulmonary veins), and hybrid m-BOX and driver ablation (HOT). OBJECTIVE: To evaluate the effectiveness of high-density mapping-guided m-BOX or HOT in patients with non-paroxysmal AF. METHODS: The study is retrospective, non-randomized, and single center. A total of 148 patients who underwent HOT and 113 patients who underwent m-BOX ablation were included in the study. All patients were scheduled for a 12-month follow-up after the procedure. Recurrence was defined as AF, atrial tachycardia, or atrial flutter lasting ≥ 30 s after the blanking period. RESULTS: The HOT group exhibited a statistically lower 12-month recurrence rate compared to the m-BOX group (21.8% vs. 34.8%, HR 0.49, 95% CI 0.30-0.80; P = 0.005). Among patients in the HOT group, those in whom sinus rhythm (SR) was restored by ablation demonstrated a numerically lower recurrence rate compared to those without SR restoration (16.7% vs. 26.7%, HR [95% CI]:0.60 [0.28-1.28]; P = 0.37). Irrespective of the ablation strategy, restoration of SR by ablation was associated with a lower recurrence rate (16.2% vs. 34.4%, HR [95% CI]:0.43 [0.24-0.76]; P = 0.01). CONCLUSION: Compared to those receiving m-BOX ablation, patients who underwent HOT ablation were associated with lower recurrence.