Is there a change in P wave parameters following pulmonary vein isolation (PVI) using radiofrequency ablation (RF) vs. cryoballoon ablation (CRYO) for paroxysmal atrial fibrillation (PAF)?

Abstract Funding Acknowledgements Type of funding sources: None. Pulmonary vein isolation (PVI) is an effective and established therapy for paroxysmal atrial fibrillation (PAF) . PVI can be performed using point by point ablation with radiofrequency (RF) or with single shot techniques such as cryoballoon (CRYO). As P waves represent atrial depolarization, we aimed to study whether P wave metrics may change after PVI and if there are differences between RF and CRYO approaches. Methods We studied 88 matched patients who had PVI for PAF between January 2017 and December 2018 (RF = 44, CRYO = 44). Each patient was in sinus rhythm (SR) prior to ablation. Patients on amiodarone and those who had additional linear ablation were excluded. Patients had continuous ECG monitoring using Labsystem Pro (Boston Scientific Inc). Sampled at 1kHz during the procedure. One-minute recordings before and after PVI were exported and analysed using custom-written software using MatLab (v2018, bandpass 1-50Hz) to annotate P wave onset, peak and end. P wave duration was heart rate corrected (PWDc) by using the Hodges formula and P wave amplitude (PWA). Results P wave metrics were comparable before PVI between both cohorts. Successful PVI was achieved in all patients. There was a trend towards an increase in PWDc in some ECG leads with either RF or CRYO but no significant difference in P wave metrics as a result of PVI ablation or between both ablation modalities. Conclusion In this study, there was no significant change seen in PVI with RF or CRYO and no difference between the 2 ablation modalities. P wave metrics comparison, RF vs CRYO PWDc (ms) PRE, RF (n = 44) POST, RF (n = 44) P PRE, CRYO (n = 44) POST CRYO (n = 44) P P (RF vs CRYO) I 134.7 ± 32 133.5 ± 35 0.813 131.9 ± 36 132.7 ± 39 0.9 0.81 II 140.9 ± 34 144.1 ± 37 0.56 139.4 ± 42 134.4 ± 40 0.51 0.41 III 131.5 ± 31 143.3 ± 37 0.04 132.8 ± 41 130.6 ± 36 0.68 0.074 AVF 137 ± 32 144.7 ± 36 0.15 137.5 ± 42 127.4 ± 37 0.11 0.141 V1 143.9 ± 33 151.8 ± 37 0.17 133.6 ± 37 143.8 ± 38 0.09 0.745 PWA (mV) PRE, RF (n = 44) POST, RF (n = 44) P PRE, CRYO (n = 44) POST CRYO (n = 44) P P (RF vs CRYO) I 0.125 ± 0.08 0.09 ± 0.06 0.002 0.13 ± 0.08 0.14 ± 0.09 0.59 0.076 II 0.238 ± 0.1 0.238 ± 0.1 0.98 0.232 ± 0.1 0.278 ± 0.2 0.1 0.212 III 0.149 ± 0.1 0.153 ± 0.1 0.83 0.189 ± 0.1 0.187 ± 0.1 0.97 0.86 AVF 0.195 ± 0.1 0.196 ± 0.1 0.92 0.197 ± 0.1 0.247 ± 0.1 0.066 0.132 V1 0.122 ± 0.1 0.151± 0.1 0.05 0.138 ± 0.1 0.193 ± 0.2 0.002 0.543 PWDc and