Comprehensive Atrial Fibrillation Burden and Symptom Reduction Post-Ablation: Insights from DECAAF II

Introduction Traditional AF recurrence after catheter ablation is reported as a binary outcome. However, a paradigm shift towards a more granular definition, considering arrhythmic or symptomatic burden, is emerging. Hypothesis We hypothesize that ablation reduces AF burden independently of conventional recurrence status in persistent AF patients, correlating with symptom burden reduction. Methods 98 patients with persistent AF from the DECAAFII trial with pre-ablation follow-up were included. Patients recorded daily single-lead ECG strips, defining AF burden as the proportion of AF days among total submitted ECG days. The primary outcome was atrial arrhythmia recurrence. The Atrial Fibrillation Severity Scale (AFSS) was administered pre-ablation and at 12-months post-ablation. Results At follow-up, 69 patients had atrial arrhythmia recurrence and 29 remained in sinus rhythm. These patients were categorized into a recurrence (n=69) and no-recurrence group (n=29). Both groups had similar baseline characteristics, but recurrence patients were older (p=0.005), had a higher prevalence of hyperlipidemia (p=0.007), and a larger LA volume (p=0.01). There was a reduction in AF burden in the recurrence group when compared to their pre-ablation burden (65% vs. 15%, p<0.0001). Utah Stage 4 fibrosis and diabetes predicted less improvement in AF burden. The symptom severity score at 12 months post-ablation was significantly reduced compared to the pre-ablation score in the recurrence group, and there was a significant correlation between the reduction in symptom severity score and AF burden reduction (R=0.39, p=0.001). Conclusion Catheter ablation reduces AF burden irrespective of arrhythmia recurrence post-procedure. There's a strong correlation between AF burden reduction and symptom improvement post-ablation. Notably, elevated left atrial fibrosis impedes AF burden decrease following catheter ablation.