The use of high-density electroanatomic mapping catheter (Advisor™ HD Grid) in detecting critical Purkinje potentials (P1-P2) in patients with left posterior fascicular VT.

BACKGROUND: In patients with left posterior fascicular ventricular tachycardia (LPF-VT), the most critical determinant of successful radiofrequency ablation (RFA) is the accurate identification of the antegrade and retrograde pathways (P1-P2) within the reentrant circuit. The aim of this study was to evaluate the impact of HD Grid-guided RFA on P1 potential detection, procedural duration, acute procedural success, and arrhythmic recurrence in patients with LPF-VT. METHODS: In this retrospective-cohort study, 25-patients with inducible tachycardia during electrophysiological study and a confirmed diagnosis of LPF-VT were included. Patients were divided into two-groups according to the use of the HD Grid Mapping Catheter during RFA: standard RFA group (Group-I) and standard RFA + HD Grid group (Group-II). Patients were followed for a mean duration of 24.8 ± 14.8 months after RFA. RESULTS: In Group-II, the frequency of P1 recording during VT and, consequently, P1-targeted RF applications was significantly higher than in Group-I (92% vs 39%, and, p = 0.008). Acute procedural success was achieved in all 12-patients (100%) in Group-II and in 9-patients (69%) in Group-I (p < 0.047). During follow-up, LPF-VT recurrence occurred in 7-patients (54%) in Group-I and 1-patient (8%) in Group-II (p < 0.020). CONCLUSION: In this study, the use of the HD Grid Mapping Catheter during RFA for LPF-VT was associated with a higher detection rate of P1 potentials compared with the standard RFA approach. Given the critical role of P1 potentials in determining procedural success, this finding may suggest a potential relationship with shorter procedural and fluoroscopy times, higher acute procedural success rates, and lower LPF-VT recurrence rates in this patient population.