Abstract 17461: Clinical Significance of No Pulmonary Vein Potential at Redo-procedure After Catheter Ablation for Atrial Fibrillation

Introduction: Long-lasting pulmonary vein isolation (PVI) has been shown to be the key determinants for clinical outcome in both patients with paroxysmal and persistent atrial fibrillation (AF). Hypothesis: Although reconnected PV potential (PVP) has been regarded as a main mechanism of AF recurrence after catheter ablation, PVIs are well preserved in some patients at redo-procedure after recurrence. Therefore, we explored the characteristics and clinical outcome of the patients with negative PVP at redo-procedure. Methods: Among 1522 patients with AF who underwent catheter ablation, 143 patients (79.0% male, 56.1±10.0 years old, 65.0% paroxysmal AF) refractory to antiarrhythmic drug underwent redo-procedure. PVP was not shown in 52 patients (PVP- group, 36.4%), but remaining 91 patients showed PVP (PVP+ group, 234/364 (64.3%) of PVs). We mapped triggers with isoproterenol infusion in both groups (after PVI in PVP+ group). Depending on mapping finding, we ablated non-PV foci and added linear ablation or complex fractionated atrial electrogram (CFAE)-guided ablation. Results: 1. PVP- group was independently associated with female gender (OR 2.64 95%CI 1.13~6.21, p=0.026) and later de novo clinical recurrence timing (OR 1.02 95% CI 1.00~1.04, p=0.047). 2. Additional linear ablations were more likely to be performed in PVP- group (92.2% vs. 61.5%, p<0.001), but total ablation time (2411.3±1082.8 vs. 3144.8 ± 1412.5 sec, p=0.003) and procedure time (164.2± 51.4 vs. 144.2±47.1 min, p=0.027) were shorter in PVP- group than in PVP+ group. 3. During 18.4±10.2 months follow-up after redo-ablation, PVP- group showed significantly higher clinical recurrence rate than PVP+ group regardless of redo-ablation strategies (Kaplan Meier, Log Rank p=0.011). The presence of recurred PV connection (PVP+) was independently associated with lower recurrence of AF after repeat ablation (HR 0.46, 95% CI 0.21 - 0.98, p=0.043). Conclusions: AF patients with well-preserved PVI recurred later timing after de novo ablation, but showed poor clinical outcome after redo-ablation procedure, suggesting a potential AF progression.