Idiopathic ventricular tachycardia (IVT) originating from the left ventricular septum is most often seen in healthy males aged 15-40 years, with a lower incidence in children than in adults, and the incidence of IVT was found to be about 0.2-0.8/10,000 during cardiac screening in schools. most of the children in this group had a long duration of disease with recurrent ventricular tachycardia that needed to be reversed by intravenous antiarrhythmic drugs, and the choice of radiofrequency ablation therapy was necessary. The choice of radiofrequency ablation is necessary. Currently, the conventional method of labeling for radiofrequency ablation treatment of ILVT originating from the left ventricular septum is the excitation sequence labeling method, which requires evoked tachycardia to be labeled, but there is instability of evoked tachycardia, including unsuccessful evocation, unsustained evoked tachycardia, or inability to repeat evocation, accounting for about 37.8%. The application of the agonistic sequential labeling method in children is limited because the suppression of myocardial excitability by surgical anesthesia increases the difficulty of ILVT induction. In our study group, 6/55 (10.9%) children with ILVT failed to induce ILVT successfully, and 28 (50.9%) ILVT could be induced by repeated sedative isoprenaline ventricular procedure stimulation, which prolonged the operation time and increased the risk of anesthesia. The literature on subsinus rhythm P-potential calibrations is poorly reported. In sinus rhythm P-potential labeling, the presence of a P-potential in sinus rhythm is indicative of catheter proximity to the target site. Because of the wide range of P potentials present, the key to success lies in the combination of radiographic localization. The advantages of the subsinus P-potential method are that it is not necessary to induce ventricular tachycardia intraoperatively, which makes it more suitable for pediatric patients requiring anesthesia; it is relatively simple to perform and significantly reduces the operative time. In our group, all 30 children with subsinus rhythm P-potential tagging were successfully ablated with a recurrence rate of 3.3% at follow-up. In China, the recurrence rate of 8.8% was reported in the literature for the agonistic sequential labeling method, which was also higher than that of the present group for the subsinus P-potential labeling method.