Long-term clinical course of patients with catecholaminergic polymorphic ventricular tachycardia: A more than 10-year follow-up cohort study.

Background: Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an inherited disorder characterized by ventricular arrhythmias induced by physical or emotional stress. Currently, there are limited data available on the long-term prognosis of CPVT.

Methods and results: In this study, which included both retrospective and prospective components, 12 patients with CPVT (7 males and 5 females) under 18 years old were enrolled to gather and evaluate demographic, clinical, and genetic data. The mean age at diagnosis onset was 7.0 ± 3.1 years. All patients experienced syncope. The mean follow-up duration was 20.1 years. During the follow-up period, all patients experienced at least one episode of supraventricular tachycardia (SVT). Despite beta-blocker therapy, nine patients experienced syncope (75%), and four patients were noncompliant with their treatment. An implantable cardiac defibrillator (ICD) implantation was performed in 10 patients (83%), and among those 5 (50%) experienced appropriate shocks. Inappropriate shocks were observed in all patients with an ICD. The left cardiac sympathetic denervation was performed in 6 patients (50%). One patient died during the follow-up period. Genetic testing was performed in eight patients, five of whom had RYR2 mutations, one patient had mutations in CASQ2, one in TECRL, and one was gene-elusive.

Conclusions: The prevalence of cardiac events, even after the initiation of beta-blocker therapy, was found to be distressingly high during long-term follow-up. SVT, such as atrial fibrillation, were found to be more common than previously thought. Combination therapy with a beta-blocker and an IC antiarrhythmic drug shows promise. An individualized approach to the selection of treatment strategies is essential.