Characterization of gap location patterns following pulmonary vein isolation with commercial pulsed-field catheters in de novo and redo AF procedures

Abstract Background Initial real-world results of pulsed-field ablation (PFA) to treat atrial fibrillation (AF) show promising efficacy and efficiency results. However, there remain cases where additional applications are required to achieve isolation. A greater understanding of factors contributing to these cases is warranted. A number of recent publications have examined the durability of lesion sets in patients with arrhythmia recurrence following PFA (1-6); however, a quantification of lesion gaps and locations has not been studied in a real-world setting. Objectives The objective of this analysis is to identify patterns of gap locations in de novo and redo AF cases following PFA. Methods Acute observational data from 850 AF procedures in which PFA was used was prospectively collected from 109 operators at 49 centers in the US, Europe, and Australia between February and October 2024. Results In this dataset, 57.6% of cases were de novo paroxysmal AF (dnPAF, 490/850), 22.5% de novo persistent AF (dnPsAF, 191/850), 7.5% redo PAF (rPAF, 64/850), and 12.4% redo PsAF (rdPsAF, 105/850). A pentaspline variable conformation PFA catheter was used in 82.1% of procedures (698/850) and a fixed loop PFA catheter was used in 17.9% of procedures (152/850). Mapping was used in 100% of procedures (EnSite X). Pulmonary vein isolation (PVI) was confirmed in 82.8% of de novo cases (82.9% of PAF and 82.7% of PsAF) and 72.2% of redo cases (73.4% of PAF and 71.4% of PsAF). First-pass isolation (FPI) was defined as isolation on first check after ablation of each set of PVs. In procedures where PVI was assessed, FPI was achieved in 79.8% of dnPAF cases (324/406) and 74.7% of dnPsAF cases (118/158, p<.05), and in 93.6% of rPAF cases (44/47) and 81.3% of rPsAF cases (61/75) (p<.05). In cases where FPI was not achieved, 112 total gaps were found in the dnPAF group (n=82/406, 20.2%),and 54 gaps were found in the dnPsAF group (n=40/158, 25.3%, p=0.2). 3 gaps were found in the rPAF group (n=3/47, 6.4%) and 17 gaps were found in the rPsAF group (n=14/75, 18.7%, p<.05). Gap occurrences by location are shown in Figure 1. Notably, gaps occurred most frequently in the left compared to the right PVs for de novo PAF and PsAF and for redo PsAF. Gaps were also found most frequently in the anterior-superior aspect of the veins in both the left and right PVs for all case types. Conclusions Gaps in AF PFA procedures occurred most commonly in the anterior-superior aspect of both the left and right pulmonary veins, consistent with findings from smaller previous studies (1-3). Further work to determine the impact of catheter shape and ablation workflows on this observed trend is warranted.Figure 1.