Comparison of P-wave parameter changes after radiofrequency ablation and cryoballoon ablation for paroxysmal atrial fibrillation: An observational cohort study.

Abstract

Background: Pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (PAF) can be performed using one-shot cryoballoon ablation (cryo) or point-by-point radiofrequency ablation (RF). This study compares the changes in P-wave parameters between both ablation methods.

Methods: This single-centre retrospective study included contact force RF and second-generation cryo for PAF between 2018 and 2019. Procedure success was defined by freedom of ECG-documented AF at 12 months. Digital 12‑leads ECGs with 1-50 hertz bandpass filters were monitored directly during the procedure. Corrected P-wave duration (PWDc), P-wave voltage (PWV), P-wave dispersion (PWDisp), and P-wave terminal force in V1 (PTFV1) were measured and compared between RF and cryo. Additional ablations outside pulmonary veins were excluded.

Results: The final analysis included 226 patients, and the freedom of AF rate was similar at the 12-month follow-up between RF and cryo (76 % vs 74 %, P = 0.12). PWDc and PWV increased and decreased, respectively in both arms. PTFV1 decreased in RF (-3.3 mm.s to -4.6 mm.s, P < 0.001) and cryo (-3.4 mm.s to -5.3 mm.s,P = 0.002). There were similar changes after RF and cryo in PWDc (F_{11, 1032} = 0.80, P = 0.85), PWV (F_{11, 1032} = 0.19,P = 0.06), and PWDisp (F_{11, 1032} = 0.16,P = 0.34) and PTFV1 (P = 0.39). Increased PWDc was correlated with failure of RF (hazard ratio [2.3], 95 % confidence interval [CI]: 1.4-5.9, p = 0.01) and cryo (HR: 2.1, 95 % CI (1.3-4.6), p = 0.02). Results were similar when patients on antiarrhythmic drugs were excluded.

Conclusion: RF and cryo caused similar freedom of AF rate at 12 months in PAF and similar P-wave parameter changes.