Abstract
Background: Catheter ablation of atrial fibrillation (AF) remains a challenging procedure. We aim to describe the EP characteristics of patients who underwent 2 or more ablations for AF. Methods: 17.7% of 243 patients (n=43) underwent repeat ablation for drug refractory AF. All patients underwent instrumentation of the left atrium (LA) after LA clots were excluded. Mapping of the pulmonary veins (PVs) and ablation to achieve PV isolation was performed. Additional triggers after induction were ablated. Results: The types of AF were paroxysmal AF (PAF) (n=25) or non-paroxysmal AF (NPAF) (n=18). Recovered PV potentials were seen in 97.7%: LSPV: 93%, RSPV 86%, RIPV 84% and LIPV 76%. 76.7% (n=33) of patients required additional ablation. NPAF patients required more ablation than PAF: CFAE (77.8% vs 8%, p<0.001), CTI (61.1% vs 20% p=0.006), LA septum (55.6% vs 24% p=0.035), coronary os (38.9% vs 4%, p=0.004), LA anterior wall (33.3% vs 0% p=0.002). Cardioversion was conducted more frequently (44.4% vs 8%, p=0.005) and procedural time (281.8mins±22.9 vs 219mins±15.7 p=0.024) was longer in NPAF vs PAF patients. Conclusion: In patients who underwent repeat AF ablation, PV recovery was seen in almost all patients. 76.7% of patients required additional ablation, especially those with NPAF.
