Korean Circ J.  2024 Dec;54(12):853-864. 10.4070/kcj.2024.0183.

Treatment Outcomes in Children With Catecholaminergic Polymorphic Ventricular Tachycardia: A Single Institutional Experience

• Lee J
• Kwon BS
• Song MK
• Lee SY
• Ko JM
• Kim GB
• Bae EJ

• KMID: 2563801
• DOI: http://doi.org/10.4070/kcj.2024.0183

Abstract

Background and Objectives
Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a life-threatening inherited arrhythmogenic disorder. Recently, RYR2, the major CPVTcausative gene, was associated with neuropsychiatric manifestations. We aimed to analyze the clinical presentations, neuropsychiatric manifestations, and treatment outcomes of children with CPVT.
Methods
We retrospectively reviewed 23 patients diagnosed with CPVT before 19 years of age. Genetic analysis, history of neuropsychiatric manifestations, changes in ventricular arrhythmia burden before and after treatment, occurrence of cardiac events, and overall survival (OS) were investigated.
Results
RYR2 variants were identified in 17 patients, and 14 were classified as pathogenic or likely pathogenic. Neuropsychiatric manifestations, including intellectual disability and attention deficit hyperactivity disorder, were identified in 10 patients (43.5%). The 5-year cardiac event-free survival rate was 31.2%, and the 10-year OS rate was 73.1%. Patients diagnosed since 2009 had a higher cardiac event-free survival rate than those diagnosed before 2009 (p=0.0028). Combined beta-blocker and flecainide therapy demonstrated a lower risk of cardiac events than beta-blocker monotherapy (hazard ratio [HR], 0.08; 95% confidence interval [CI], 0.02–0.38; p=0.002). Left cardiac sympathetic denervation (LCSD) reduced the ventricular arrhythmia burden in Holter monitoring. Occurrence of near-fatal cardiac events after diagnosis was an independent predictor of death (HR, 33.40; 95% CI, 6.23–179.95; p<0.001).
Conclusions
Neuropsychiatric manifestations are common in children with CPVT. Flecainide and/or LCSD, when added to beta-blocker therapy, reduce the ventricular arrhythmia burden and cardiac events, thereby improving treatment outcomes in recent years.

Keyword

Catecholaminergic polymorphic ventricular tachycardia; Channelopathies; Ryanodine receptor calcium release channel; Intellectual disability; Attention deficit disorder with hyperactivity

Figure

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  Figure 1 Flowchart of the study population and treatment.BB = beta-blocker; CPVT = catechoaminergic polymorphic ventricular tachycardia; FCN = flecainde; LCSD = left cardaic sympathetic denervation.

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  Figure 2 Typical bidirectional polymorphic VT was observed during Holter monitoring, and subsequently, implantable cardioverter-defibrillator shock therapy (blue arrow) was delivered. However, the VT was not terminated; instead, it accelerated.pVT = polymorphic ventricular tachycardia; VE = ventricular ectopy; VT = ventricular tachycardia.

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  Figure 3 Cardiac event-free survival and overall survival. Kaplan–Meier estimates of (A) cumulative cardiac event-free survival and (B) OS in patients with catecholaminergic polymorphic ventricular tachycardia after diagnosis.

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  Figure 4 Cardiac event-free survival and overall survival according to year of diagnosis. Kaplan–Meier estimates of (A) cumulative cardiac event-free survival and (B) OS according to year of diagnosis in patients with catecholaminergic polymorphic ventricular tachycardia after diagnosis.

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