BMC Cardiovasc Disord. 2026 Oct 19;26(1):973. doi: 10.1186/s12872-026-06779-5.
ABSTRACT
BACKGROUND: Slow-pathway (SP) ablation is the established therapy for atrioventricular nodal re-entrant tachycardia (AVNRT). While conventional anatomical and electrogram-guided approaches are effective, SP localization may be challenging in a subset of procedures. Omnipolar near-field (OTNF) peak frequency (PF) mapping has been proposed as a signal-based approach to support SP localization; however, prospective multicenter data remain limited.
METHODS: Fifty consecutive adults with inducible typical AVNRT underwent catheter ablation in three Italian hospitals. High-density right atrial mapping was performed during sinus rhythm using a 16-pole grid catheter (Advisor™ HD Grid) with OTNF on the EnSite X system. PF maps were generated (high-frequency threshold > 250 Hz), and RF applications were delivered to the region of highest PF. Voltage maps were also created to delineate low-voltage bridge (LVB) regions (typically 0.04-2 mV) for retrospective overlap/localization analyses; LVB was not used to select ablation targets.
RESULTS: Acute procedural success was achieved in all patients, with no procedural complications. The effective ablation site (junctional beats with subsequent SP modification and/or non-inducibility) corresponded to the highest PF region in 45/50 patients (90%). In a retrospective overlap/localization analysis, the effective site fell within the LVB region in 36/50 patients (72%); concordance between PF-defined and LVB-defined regions at the effective site was observed in 35/50 patients (70%). Mean PF in the SP target region was 424 ± 86 Hz versus 272 ± 57 Hz in surrounding tissue (P < 0.05 on paired testing). Exploratory ROC analysis yielded an AUC of 0.937 with an optimal cutoff of 357 Hz (sensitivity 0.87; specificity 0.94); these estimates should be interpreted cautiously because PF guided RF target selection (incorporation/target-selection bias).
CONCLUSION: In this prospective multicenter cohort, OTNF-derived PF mapping was feasible and reproducibly identified a discrete region used to guide SP ablation in typical AVNRT. ROC-derived thresholds and performance estimates are exploratory and require independent validation in cohorts where ablation targets are not selected using PF criteria.
PMID:42926208 | DOI:10.1186/s12872-026-06779-5

