Does pulsed field ablation regress over time? A quantitative temporal analysis of pulmonary vein isolation

Abstract

BACKGROUND The tissue specificity of pulsed field ablation (PFA) makes it an attractive energy source for pulmonary vein (PV) isolation (PVI). However, beyond each PFA lesion's zone of irreversible electroporation and cell death, there may be a surrounding zone of reversible electroporation and cell injury that could potentially normalize with time.OBJECTIVE The purpose of this study was to assess whether the level of electrical PVI that is observed acutely after PFA regresses over time.METHODS In a clinical trial, patients with paroxysmal atrial fibrillation underwent PVI using a biphasic PFA waveform delivered through a dedicated, variably deployable multielectrode basket/ flower catheter. Detailed voltage maps were created using a multispline diagnostic catheter immediately after PFA and again w3 months later in a prospective, protocol-specified reassessment procedure. We analyzed 20 patients who underwent PFA with durable PVI and available maps from both time points. To compare the ablated zones, the left-and right-sided PV antral isolation areas and nonablated posterior wall area were quantified and the distances between left and right PV low-voltage edges were measured.RESULTS A comparison of voltage maps immediately after PFA and at a median of 84 days (interquartile range 69-90 days) later revealed that there was no significant difference in either the leftand right-sided PV antral isolation areas or nonablated posterior wall area. The distances between low-voltage edges on the posterior wall were also not significantly different between the 2 time points.CONCLUSION This study demonstrates that the level of PV antral isolation after PFA with a multielectrode PFA catheter persists without regression.

Pulsed‐field ablation combined with ultrahigh‐density mapping in patients undergoing catheter ablation for atrial fibrillation: Practical and electrophysiological considerations

“…The therapeutic waveform was structured as a hierarchical set of biphasic, microsecond‐scale pulses released in a bipolar fashion between the electrodes. The generator output ranged from 1.8 to 2.0 kV) per application, 3 with 1.9 kV selected for PVI in our study protocol.…”

“…In patients who received only PVI : The following spatial measurements were made consistent with a previously‐published method 3 : (1) the surface areas of the posterior left‐ and right‐sided PV antral isolation, (2) the LAPW surface area with voltage pre‐ and post‐PFA, and (3) the distance between the ipsilateral, antral levels of isolation at superior, middle and inferior latitudes of the LAPW, 3 (Figures 1A,B and 1D). The surface area of each PV ostium and the area of the circular antral ablation lesion was measured around each ipsilateral PV pair (Figure 1C).…”

“…Additionally, peri-and postprocedurally, the included signal processing software (Lumipoint™, Boston Scientific) was used to analyze fractionation and complex components of activation (peak cutoff: 5-7) along the ablation sites and border zone of ablation lesions. 6 In patients who received only PVI: The following spatial measurements were made consistent with a previously-published method 3 : (1) the surface areas of the posterior left-and right-sided PV antral isolation, (2) the LAPW surface area with voltage pre-and post-PFA, and (3) the distance between the ipsilateral, antral levels of isolation at superior, middle and inferior latitudes of the LAPW, 3 (Figures 1A,B and 1D). The surface area of each PV ostium and the area of the circular antral ablation lesion was measured around each ipsilateral PV pair (Figure 1C).…”

“…1,2 One study using high-density mapping demonstrated that the level of antral pulmonary vein (PV) lesion does not regress over time. 3 Visualization of the current multielectrode PFA catheter within a threedimensional (3D) mapping system potentially facilitates catheter handling and enhances ablation while decreasing the need for fluoroscopy. In this study, we assessed acute PFA lesion formation (by the Farwave catheter, Farapulse Inc.) and level of PV isolation using ultrahigh-density mapping (UHDx; with the multi-electrode Orion™ mapping catheter and the Rhythmia™ 3D mapping system, Boston Scientific) combined with PFA catheter visualization in symptomatic AF patients undergoing PVI by PFA, including persistent AF patients receiving additional PFA lesions.…”

“…Yet, clinical experience is limited and especially data regarding lesion characterization is sparse but highly relevant 1,2 . One study using high‐density mapping demonstrated that the level of antral pulmonary vein (PV) lesion does not regress over time 3 . Visualization of the current multielectrode PFA catheter within a three‐dimensional (3D) mapping system potentially facilitates catheter handling and enhances ablation while decreasing the need for fluoroscopy.…”