Incidence and Impact on Arrhythmia Recurreces of Atrial Fibrillation Termination During Linear Radiofrequency Ablation in the Left Atrium

Abstract Atrial Fibrillation Termination During Linear Radiofrequency Ablation in the Left Atrium: Incidence and Impact on Arrhythmia Recurrences Background Termination of atrial fibrillation (AF) during persistent atrial fibrillation (peAF) ablation is infrequent and has shown no clear association with reduced recurrences during follow-up. Linear ablation, often considered to have minimal impact on efficacy, has been primarily explored through creating ablation lines from the mitral annulus to the inferior pulmonary vein or by isolating the posterior wall. Purpose This study aims to assess the incidence of AF termination using an alternative linear ablation approach and its correlation with arrhythmia recurrence during follow-up. Methods Patients enrolled in the PowerFast III trial (a multicenter randomized trial comparing high- power short-duration radiofrequency (RF) application to conventional RF application) with peAF and undergoing linear ablation were included in this sub-study. Conventional pulmonary vein isolation (PVI) was performed using two different RF settings along with a set of RF lines, including anteroseptal (AS), anterolateral (AL), posterior wall isolation between the pulmonary veins, and between the two anterior lines. Patients were categorized into two groups based on AF termination or flutter organization (Group 1) or no AF termination (Group 2) during RF application. All patients were monitored with EKG transmission for one year. Results Fifty-one consecutive patients (mean age 61 years, male 39) were included. AF terminated in 21 patients (41%) during RF application (9 converting to AF and 12 to atrial flutter). AF did not terminate during RF application for PVI, except for one patient during right PV ablation following left PVI. AF termination occurred by posterior wall lines in three patients, roof line in three, and anterior line in two. AF converted into atrial flutter during ablation by a roof line in 5 patients and by an anterior line in 7. No significant differences in atrial arrhythmia recurrence were observed between the two groups (three patients in Group 1 vs. eleven in Group 2, P = 0.11). However, Group 1 exhibited fewer AF recurrences (zero patients) than Group 2 (eight patients, P = 0.015). Conclusions Extensive linear RF ablation resulted in a substantial proportion of patients experiencing AF termination or conversion into atrial flutter. AF termination or conversion did not appear to be correlated with atrial arrhythmia freedom during follow-up but was associated with fewer AF recurrences.Any arrhythmia recurrenceAF recurrence