Arrhythmic Risk and Clinical Features in Catecholaminergic Polymorphic Ventricular Tachycardia: Results From a...

Area of Science:

• Pediatric Cardiology
• Clinical Genetics
• Cardiac Electrophysiology

Background:

• Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a rare, life-threatening inherited arrhythmia in children, often leading to sudden cardiac death (SCD).
• Risk stratification and effective management strategies for pediatric CPVT remain challenging.
• Understanding the clinical and genetic landscape of CPVT in specific populations is crucial for improving patient outcomes.

Purpose of the Study:

• To assess the clinical characteristics, genetic profiles, and risk factors for adverse outcomes in Korean pediatric patients with CPVT.
• To evaluate the effectiveness of current therapeutic interventions, including triple therapy and implantable cardioverter-defibrillators (ICDs).
• To provide data that can guide future therapeutic decision-making for pediatric CPVT.

Main Methods:

• A multicenter registry analysis of 39 pediatric CPVT patients from 16 centers in Korea.
• Evaluation of demographics, clinical management, and outcomes, including breakthrough cardiac events (BCE), aborted cardiac arrest (ACA), and SCD.
• Analysis of genetic testing results, primarily focusing on RYR2 mutations, and assessment of treatment efficacy (beta-blockers, flecainide, left cardiac sympathetic denervation (LCSD), ICDs).

Main Results:

• The mean age at diagnosis was 9.9 years, with a significant delay from symptom onset.
• RYR2 mutations were identified in the majority of genetically tested patients (24/29).
• Over a median follow-up of 59 months, 46.1% experienced BCE, 25.6% ACA, and 10.3% SCD. Triple therapy (beta-blockers, flecainide, LCSD) reduced BCEs (p=0.044) but not ACA/SCD (p=0.363). ICDs showed a trend in preventing ACA/SCD (p=0.067) but were associated with frequent complications.

Conclusions:

• Korean pediatric CPVT patients exhibit clinical and genetic features consistent with global cohorts.
• Triple therapy involving beta-blockers, flecainide, and LCSD is effective in reducing breakthrough cardiac events but does not prevent sudden cardiac death.
• While ICDs may offer a trend towards preventing aborted cardiac arrest or sudden cardiac death, their use in pediatric CPVT is associated with significant complications, necessitating careful consideration.