Abstract:

Objective To investigate the clinical manifestations, treatment and follow-up of RYR2 gene variation-related catecholaminergic polymorphic ventricular tachycardia (CPVT). Methods The clinical data of CPVT children admitted from January 2017 to January 2023 were retrospectively analyzed, and the course of treatment and follow-up results were summarized. Results A total of 6 children (4 boys and 2 girls) with CPVT were admitted, and the mean age of the patients was (3.5±0.5) years old when the first symptoms appeared. The median time from first symptom onset to diagnosis was 1.5 (0.1-5.9) years. The most common clinical manifestation was syncope, with exercise and emotions being the main triggers. All 6 children had de novo missense mutations in the RYR2 gene identified through whole-exome sequencing. In dynamic electrocardiography, atrial arrhythmias and sinoatrial node dysfunction were commonly observed in younger children. Four patients underwent exercise stress testing, with 2 experiencing bidirectional ventricular premature contractions and 2 experiencing bidirectional ventricular premature contractions and polymorphic ventricular tachycardia. Initial treatment involved oral propranolol or metoprolol. If arrhythmias persisted, flecainide or propafenone was added as adjunctive therapy. Two patients received permanent cardiac pacemaker treatment (VVI). The mean follow-up time was (24.3±3.7) months, and all patients survived. During the follow-up period, 3 children had occasional syncope, 1 had intermittent palpitation, and 2 had no discomfort. Conclusions CPVT associated with RYR2 gene variations in children can present with various clinical manifestations. Atrial arrhythmias combined with sinoatrial node dysfunction are commonly observed in younger children. The combination of pharmacological therapy and cardiac pacemaker treatment yields favorable treatment outcomes.

Key words: RYR2 gene, catecholaminergic polymorphic ventricular tachycardia, child