Background: There is significant interpatient variability regarding the timing of the earliest local activation relative to surface QRS during
premature ventricular complex (PVC) ablation. The aim of the present study is to evaluate whether catheter-induced premature ventricular
complexes (PVCs) produced at the presumptive ablation site may aid in the identification of the optimal timing of the earliest local activation
for the successful ablation of clinical PVCs.
Methods: Sixty-three consecutive patients (35 males, age: 53.5 ± 14.4 years) without any exclusion criteria who had undergone PVC ablation
between 01/07/2018 and 01/07/2019 constituted our study population. Catheter-induced PVCs were generated at the site with presumptive
PVC origin according to the ECG criteria during the procedure of PVC ablation. Five PVCs were induced by mechanical stimulation
in separate points, and the time interval between the beginning of EGM at catheter tracing and the beginning of the QRS complex of each
catheter-induced PVC was noted. The mode of five time intervals (Cath EGM-ECG) was used in the analysis. The time interval between the
beginning of local EGM of clinical PVCs at the earliest site and the beginning of the QRS complex of clinical PVCs (PVC earliest EGM-ECG)
was also noted. The value of Cath EGM-ECG as a reference for procedural success of ablation was evaluated by examining the relationship
between Cath EGM-ECG and PVC earliest EGM-ECG.
Results: Fifty-two patients had successful ablation, and 43 of them (82.7%) had PVC earliest EGM-ECG values greater than or equal to
Cath EGM-ECG. Eleven patients had procedural failure, and all of them had PVC earliest EGM-ECG values lower than Cath EGM-ECG
(Table 1). A PVC earliest EGM-ECG value -1.5 ms greater than Cath EGM-ECG predicted successful ablation with a sensitivity of 90.4%
and a specificity of 100.0% in the general patient population (Figure 1).
Conclusion: The results of the present study indicate that catheter-induced PVCs generated at the site of the presumptive source of origin
of clinical PVCs may guide the timing of the earliest site during clinical PVC ablation. Further studies are required to validate our results and
test the predictive value of Cath EGM- ECG interval for long-term success of PVC ablation.