Outcomes of Ventricular Tachycardia Catheter Ablation in Pediatric Arrhythmogenic Right Ventricular Cardiomyopathy.

BACKGROUND

Radiofrequency catheter ablation (RFCA) of ventricular tachycardia (VT) in arrhythmogenic right ventricular cardiomyopathy is safe and reduces ventricular arrhythmia burden. Previous studies included adult patients, and data on pediatric patients are scarce. The objective of our study was to report on the safety and efficacy of RFCA in pediatric arrhythmogenic right ventricular cardiomyopathy.

METHODS

Fifteen patients who fulfilled the 2010 arrhythmogenic right ventricular cardiomyopathy task force criteria, clinically presented before the age of 18, and underwent VT RFCA procedures at ≤21 years old were included. Baseline characteristics, genotypic and phenotypic data, and ablation outcomes were collected.

RESULTS

The mean age at symptom onset was 15.5±1.6 years, and at the index procedure was 18.1±2 years, with 73% of the patients being male. Pathogenic mutation in desmosomal genes was detected in 87%. First presentation symptoms included palpitations (33%), syncope (27%), sustained VT (27%), and sudden cardiac arrest (13%). ECG repolarization abnormalities were present in 93% and 40% were reported to be athletes. In the index RFCA procedure, sustained monomorphic VT was induced in 60%. Electroanatomic mapping showed 100% basal RV epicardial substrate and 54% endocardial low voltage/scar. Repeat VT ablation was required in 80% over a mean follow-up of 16.4 months. The median number of procedures was 2 (interquartile range, 2-4), with sustained VT-free survival of 73% over a mean follow-up duration of 21.4 months. No acute periprocedural complications occurred. Bilateral cardiac sympathetic denervation due to recurrent ventricular arrhythmia was performed in 27%. Eventually, 2 patients (13%) developed advanced heart failure and underwent heart transplantation.

CONCLUSIONS

Pediatric arrhythmogenic right ventricular cardiomyopathy RFCA is safe, but early recurrences are common, requiring repeat ablations and sometimes bilateral cardiac sympathetic denervation. The substrate is mostly epicardial with preserved endocardial voltage. VT free survival is 73% after multiple procedures. Progressive heart failure requiring transplantation occurred in 13% within 2 decades of initial presentation.