Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT) – the Paediatric Experience in New South Wales (NSW)

To describe the mode of presentation, diagnosis, and management outcomes in children with catecholaminergic polymorphic ventricular tachycardia (CPVT) in NSW since 2000. An ongoing retrospective audit of medical records was performed at The Sydney Children’s Hospital Network. Children (0-18 years of age) with CPVT diagnosed after January 1, 2000, were identified from the hospital’s inherited arrhythmia and out of hospital cardiac arrest (OOHCA) database. Descriptive statistical analysis was performed on Microsoft Excel. Ethics:2021/STE02841. To date, 25 children, 15 (60%) male, were identified with CPVT. Modes of presentation included: 16 (64%) OOHCA, 5 (20%) syncope, and 4 (16%) familial screening. The mean age at diagnosis was 8.7 years (range, 0.3–15.6 years). Diagnosis was suspected clinically in 22 and on genetic testing in 3. Pathological variants on genetic testing were found in 19/24 [14 RYR2, 2 CASQ2, 1 CALM1, 1 CALM2, 1 TECRL] and a variant of uncertain significance (VUS) in 1/24. Initial treatment included a beta blocker medication in 24 (96%) and combination beta blocker/flecainide in 1 (4%). Flecainide was subsequently added to beta blocker treatment in 9 children, and one received combination Sotalol/Verapamil. An Automatic Implantable Cardioverter-Defibrillator (AICD) was implanted in 15 (60%) participants. Left cardiac sympathetic denervation was performed in 5 (20%). Eleven cardiac events occurred in 8 (32%) children after diagnosis. Two children had multiple events and there was one death. CPVT in children usually presents with cardiac arrest and RYR2 is the dominant genotype. Further analysis regarding concerning breakthrough cardiac events is underway.