High-frequency areas identified by omnipolar technology near-field mapping as a precise landmark for successful accessory pathway ablation

Background/Introduction Catheter ablation (CA) is the established curative therapy for atrioventricular reentrant tachycardia (AVRT). However, precise localisation of accessory pathways (APs) using conventional local activation time (LAT) mapping can be challenging due to far-field signal interference and broad conduction patterns on standard maps. Omnipolar technology near-field (OTNF) offers a novel frequency-based analysis to isolate true localised signals, yet its clinical utility in guiding AP ablation remains to be established in large case series. Purpose We aimed to comprehensively characterise the spatial relationship between high-frequency areas identified by OTNF-derived peak frequency maps and successful AP ablation sites to determine its potential as a novel electrophysiological landmark for precise targeting. Methods In this multicentre retrospective study, we enrolled 33 consecutive patients undergoing CA for AVRT. High-density mapping was performed using a grid-style multi-electrode catheter. Offline peak frequency analysis was conducted by incrementally increasing the upper-frequency cutoff on OTNF maps to delineate localised high-frequency areas. We quantitatively measured four parameters: (1) peak frequency at the exact successful ablation site, (2) the highest peak frequency in its immediate vicinity, (3) the spatial distance between these two points, and (4) the directional displacement of the highest frequency area relative to the successful site when viewed from the annulus. Results Acute procedural success was achieved in all 33 patients (mean age 52 ± 18 years; 64% concealed APs). Successful ablation sites consistently exhibited high peak frequencies (mean 332 ± 206 Hz). However, in every case, a discrete area with a significantly higher peak frequency (mean 435 ± 56 Hz; p < 0.01) was identified in the immediate vicinity, rather than at the exact successful site. This highest-frequency area was spatially dissociated from the successful ablation site by a mean distance of 2.8 ± 2.9 mm. Analysis of this spatial displacement revealed that while 21 cases (64%) showed co-localisation within the resolution of the map, a distinct directional shift was observed in others: 9 cases (27%) exhibited a counter-clockwise shift and 3 cases (9%) showed a clockwise shift along the annulus. Conclusion(s) OTNF-derived peak frequency maps consistently identify critical high-frequency areas that are adjacent to, but often spatially distinct from, the requisite site for durable AP ablation. This quantifiable spatial dissociation likely reflects the oblique anatomical course of APs. Recognition of this "highest frequency" landmark may serve as a novel roadmap to improve the precision and efficiency of AP catheter ablation.