How to easily detect residual conduction gaps in redo procedure of pulmonary vein isolation: Post Encircling Mapping (PEM)

Abstract

Abstract Background Pulmonary vein isolation (PVI) is the cornerstone of the interventional catheter-based treatment of atrial fibrillation. Unfortunately, persistent pulmonary vein isolation is difficult to achieve, and up to 70% of pulmonary vein reconnection rate has been documented (1). Atrial mapping during pacing from CS in combination with LAT (local activation time) mapping may help to identify these residual gaps (2). Methods We collected data from consecutive radiofrequency (RF) redo PVI procedures performed in our center from 01/01/2022 to 01/10/2023. Re-isolation was obtained based on bipolar map and Local Activation Time (LAT) map during pacing from distal coronary sinus (CS) -table 1 for the workflow-. We compared data obtained from analysis of bipolar maps and LAT maps; "discrepancy" between bipolar map and LAT map was defined as a difference which may lead to a different approach to the ablation strategy (figure 1); then, we compared procedural timing (radiofrequency time, fluoroscopy time, and skin-to-skin time) with our historical cohort of RF redo PVI procedures (01/01/2011 – 31/12/2021). Results We performed 34 radiofrequency redo procedure from 01/01/2022 to 01/10/2023. In 13 out of 112 veins treated (11.6%), we observed discrepancy between bipolar map and LAT map. We observed a lower radiofrequency time for patients treated on the basis of LAT map (01-01-2022 – 01-10-2022) when compared with our historical cohort (1023.21 ± 521.51 sec vs 1358.50 +/- 746.53 sec, p= 0.038); no differences were found in terms of skin-to-skin time and fluoroscopy time. Conclusions To perform a LAT map during pacing from distal CS may help to better identify residual gaps in redo AF procedures, allowing a reduction in radiofrequency time, without increasing skin to skin time and fluoroscopy time.Discrepancy between bipolar and LAT map