Clinical significance of ECG characteristics from single-lead ECG patch on atrial fibrillation recurrences after pulmonary vein isolation

Abstract Background Pulmonary vein isolation (PVI) is a well-established treatment for symptomatic atrial fibrillation (AF), demonstrating high efficacy and safety. However, early depolarization variabilities are observed after PVI due to acute inflammation and oedema resulting from energy delivery and tissue healing process. The prognostic value of those changes remains uncertain. Objective We aimed to analyse the clinical significance of atrial and ventricular depolarization properties on AF recurrences (RAF) in the CAMAFIB trial participants, where patients after cardioversion or after PVI were recruited and monitored with a single-lead ECG-patch (Zio XT, iRhythm, CA) for 14 days. Methods Only patients after the first PVI were included. Patients without known follow-up were excluded. The ECG tracings were processed using custom software providing signal averaged beats and used to measure the duration of the P wave PR duration, and QRS complex. P wave morphology (positive, negative, biphasic, notched) and P and QRS amplitudes were also collected. All measurements were extracted from the patch ECG the first day after PVI; all were manually adjudicated. Results There were 36 women (34%) out of 107 subjects analysed. Patients who had RAF during the first 12 months had lower mean ejection fraction (56% vs. 60%, p=0.034). No other significant differences in baseline population characteristics were observed. Patients with RAF had higher QRS amplitude (2.6 vs 2.2, p=0.044). In the subanalysis of patients who had the patch placed for at least 7 days patients with RAF more often had abnormal P wave morphology (p=0.033). Moreover, a cutoff P wave duration for predicting AF recurrence has been established at 100ms (OR=3.46 [95% 1.42-8.30], p=0.006). Conclusions We identified a set of ECG characteristics, recorded using a single-lead ECG patch, that are associated with RAF at 12 months.ECG characteristics