Abstract: Objective To explore the clinical effect of radiofrequency catheter ablation (RFCA) guided by Carto 3 for ventricular premature beats (VPBs) and the changes of autonomic nerve function before and after RFCA of the right ventricular outflow tract in children. Methods The clinical data of 42 children with frequent VPBs admitted from January 2015 to December 2019 were retrospectively analyzed. The heart rate variability (HRV) and deceleration capacity of rate (DC) of children with VPBs originated from the right ventricular outflow tract (RVOT) before and 3 months after operation were compared. Results There were 23 cases of VPBs originated from the RVOT, 5 cases from tricuspid annulus, 4 cases from right ventricular free wall, 4 cases from left ventricular outflow tract, 2 cases from mitral annulus and 2 cases from left posterior branch. Among them, 2 cases had delayed postoperative healing, 1 case recurred. The other 2 cases failed. The surgical success rate was 92 . 9 % ( 39 / 42 ), and there were no surgical complications. The 24 -hour dynamic ECG HRV index before and 3 months after RFCA of the right outflow tract in 23 children with VPBs showed that the time domain index, namely the standard deviation of normal R-R intervals (SDNN), was higher than that before RFCA, and the difference was statistically significant (P< 0 . 05 ). The frequency index, namely high frequency power (HF), was higher after RFCA than before, and the ratio of high and low frequency power (LF/ HF) was lower after RFCA than before, and the differences were statistically significant (P< 0 . 05 ). The DC value after RFCA was higher than that before RFCA, and the difference was statistically significant (P< 0 . 05 ). Conclusions The RFCA guided by Carto 3 is safe and effective in the treatment of VPBs in children. The children with VPBs originated from right ventricular outflow tract show impaired autonomic nerve function, mainly weakened vagus nerve tone.

Key words: radiofrequency catheter ablation; ventricular premature beats; right ventricular outflow tract; antonomic nerve; child