Adherence to CLOSE protocol, high-power and low baseline generator impedance predicts durable pulmonary vein isolation

Abstract

Abstract Background Atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI) is predominantly attributed to pulmonary vein reconnection (PVR). Predictors of AF recurrence were widely studied. However, data are scarce on the procedural parameters that predict chronic PVR. Aims to study the PVR rates and the predictors of PVR after initial PVI procedure. Methods We included 100 consecutive patients who underwent repeated ablation due to AF recurrence after initial PVI with the CARTO system, both procedures performed between 2018 and 2023. Results The mean age of the patients was 60 ± 12 years, 36% were female, and 44% had persistent AF. Thirty-eight patients underwent initial CLOSE-guided, and sixty-two underwent initial non-CLOSE PVI. Repeat procedure was performed 21 ± 14 months after the initial procedure. In total, PVR was found in 192 of 373 PVs (51.5%) and all PVs were isolated in 17/100 (17%) patients. Factors associated with all PVs being isolated were adherence to the CLOSE protocol (39.5% vs. 3.5%, p < 0.0001), higher delivered mean power (37.5W vs 30W, p = 0.027), presence of first-pass isolation (88.2% vs 40.4%, p = 0.0007), and lower baseline generator impedance (127.6 vs 136.6 Ω, p = 0.0027; respectively). Baseline generator impedance >130 Ω (AUC = 0.7403, sensitivity: 77.1%, specificity: 68.8%, p = 0.0032) was associated with significantly higher probability of PVR (OR = 6.757; p < 0.0001). Conclusions Our findings indicate that adherence to the CLOSE protocol, higher power setting, first-pass isolation, and baseline generator impedance <130 Ω during AF ablation improves the durability of PVI and reduces the incidence of PVR.