High-Frequency Electrograms Abolition as a Valuable Target for Remap During Ventricular Tachycardia Ablation. The HF REMAP Study.

Background

peak frequency (PF) analysis has recently emerged as a novel tool to assess electrogram properties through their frequency spectrum. PF is an indirect marker of local myocardial activity, and its reduction after radiofrequency ablation reflects effective tissue modification.

Objective

our study aims to evaluate PF analysis as an objective method to validate lesion efficacy during ventricular tachycardia (VT) ablation.

Methods

we retrospectively analyzed 43 (out of 247) consecutive patients who underwent VT ablation between January 2023 and December 2024, using the EnSite X mapping system with Advisor HD Grid catheter (Abbott, Minneapolis, USA). Complete pre- and post-ablation high-density sinus rhythm maps were obtained. PF analysis was applied offline to quantify the residual high-frequency (HF) electrogram burden, expressed as a percentage of the ablated area. Patients were stratified according to residual HF burden, and outcomes were assessed with Kaplan-Meier survival analysis and Cox regression analysis.

Results

During a median follow-up of 372 days, 11 patients reached the primary endpoint (VT recurrence or arrhythmic storm). Patients with <70% residual HF post-ablation had significantly higher VT-free survival (≈90% at 12 months) compared to those with ≥70% residual HF (≈25%; log-rank p<0.001). Cox regression confirmed residual HF ≥70% as an independent predictor of recurrence (HR 13.36; 95% CI 3.52-50.7; p<0.001).

Conclusion

PF analysis during re-mapping provides an operator-independent, reproducible tool to validate lesion efficacy. A low post-ablation residual HF burden is associated to a significantly increased VAs-free survival rate.