Objectives To investigate the success rate, factors associated with recurrence, safety and effects of age on results of radiofrequency catheter ablation (RFCA) for different types of tachyarrhythmias in children.
Methods 1000 children diagnosed as tachyarrhythmias underwent electrophysiological study (EPS), mean age 7.6 ± 3.8 years (0.33∼16.5 years). Analyse RFCA methods and results for different kinds of tachyarrhythmias along with recurrence and complications. Compare RFCA results for different age groups.
Results 1000 children underwent EPS. Results showed the numbers of atrioventricular reentrant tachycardia (AVRT) was 560 (56%), atrioventricular nodal reentrant tachycardia (AVNRT was 210 (21%), ventricular tachycardia/ventricular premature contraction (VT/PVC) was 159 (15.9%), Focal atrial tachycardia (FAT) was 49 (4.9%), atrial flutter/incisional reentrant atrial tachycardia (AF/IRAT) was 22 (2.2%). Totally 958 children underwent RFCA, success rate was 96.2%, recurrence rate 8.1%. EPS performed on recurred cases showed restoration of primary pathway/origin was 5.3%, appearence of new pathway/origin was 2.8%. 533 AVRT cases underwent RFCA, success rate was 98%, recurrence rate 8.4%, restoration of primary pathway 4%, appearence of new pathway was 4.4%. Success rate for right anterior/mid septal pathway was relatively low (85.3%), and its rate for restoration of primary pathway was high (31%). 205 AVNRT cases underwent RFCA, success rate was 100%, recurrence rate 5.9%, restoration of primary origin 4.9%. 22 AF/IRAT cases underwent RFCA, success rate was 95.5% with no recurrence. 46 FAT cases underwent RFCA, success rate was 84.8%; success rates for two-dimensional mapping group and three-dimensional mapping combined with cool-tip ablation group were 62.5% and 96.7% individually and the difference was significant (P < 0.05),10 cases recurred of which 7 originating from atrial appendages, and these 7 cases were successfully cured by appendectomy. 152 VT/PVC cases underwent RFCA, success rate was 89.5%, recurrence rate 6.6%, restoration of primary origin was 5.9%. There’re no difference of success rates between different age groups. The gross success rates and success rates for different types of arrhythmias between early and late periods were not different, while recurrence rates for AVNRT and left anterior pathways in early periods were significant higher than late periods (P < 0.05). There’re totally 8 complications (0.84%), including 2 complete atrioventricular block and 1 anaesthetic accident which happened in early period. The other 5 were vascular complications, and there’re no death.
Conclusions 1) RFCA can be safely used as frontline treatment to cure some kinds of tachyarrhythmias in children with high success rate and low recurrence rate. 2) There’re no difference for rates of success, recurrence and complication between younger and older children, while difficulty for procedure increased for the former so that caution should be made for selection of patients. 3) Application of three-dimensional mapping for difficult arrhythmias can increase success rate for ablation. 4) Proficient experience and skillful manipulation are the main factors to avoid complications.