Changes in Lead Parameters of Cardiac Implantable Electronic Devices After VT/VF Ablation Using a Dual-Energy...

Interactions between cardiac implantable electronic devices (CIEDs) and pulsed field ablation (PFA) have been studied mainly in the context of atrial ablation, whereas the effects of ventricular ablation using a dual-energy lattice-tip catheter on ventricular leads remain unclear.

This retrospective study involved 79 patients (mean age 60.9 ± 13.6 years) with an implantable cardioverter-defibrillator or cardiac resynchronization therapy defibrillator who underwent ventricular ablation using a lattice-tip catheter between February 2024 and November 2025. Pacing thresholds were assessed before, immediately after, and 3 months after ablation and standardized to a pulse width of 0.4 ms using the Lapicque-Weiss model. Marked acute threshold elevation was defined as an increase in pacing threshold of ≥ 1.0 V immediately after ablation. The anatomical relationship between ablation sites and ventricular lead locations was assessed based on the American Heart Association 17-segment model of the left ventricle and classified as corresponding when ablation involved the same or opposing ventricular region as the lead location, adjacent when ablation involved a directly adjacent region, and remote otherwise.

Marked acute pacing-threshold elevation occurred in 5 of 79 right ventricular (RV) leads (6.3%) and 2 of 22 evaluable left ventricular (LV) leads (9.1%). For RV leads, marked threshold elevation occurred in 4 of 14 patients (28.6%) in the corresponding group, 1 of 19 (5.3%) in the adjacent group, and none of 46 (0%) in the remote group. When threshold change was analyzed as a continuous variable, the acute increase was significantly greater in the corresponding group (+ 0.74 V; 95%CI 0.465-1.018) than in the adjacent (+ 0.31 V; 95%CI 0.076-0.550) and remote (+ 0.007 V; 95%CI - 0.145-0.160) groups. For LV leads, the pacing threshold increased significantly after ablation involving the corresponding segment (+ 0.71 V; 95%CI 0.167-1.245), although the overall association between anatomical relationship and threshold change was not significant. At 3 months, pacing thresholds in the corresponding groups were not significantly different from baseline for either RV or LV leads.

Marked acute pacing-threshold elevation was observed in both RV and LV leads after ventricular arrhythmia ablation using a dual-energy lattice-tip catheter. However, both RV and LV thresholds were no longer significantly different from baseline at 3 months. These findings suggest the importance of considering the anatomical relationship between ablation sites and CIED leads and of careful peri-procedural assessment of lead function during ventricular ablation.