International Multicenter Cohort Study on Beta-Blocker-Free Treatment Strategies for Catecholaminergic Polymorphic Ventricular Tachycardia Patients

JACC Clin Electrophysiol. 2024 Nov 5:S2405-500X(24)00869-7. doi: 10.1016/j.jacep.2024.10.005. Online ahead of print.

Abstract

Background: Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a rare, potentially life-threatening genetic heart disease. Nonselective beta-blockers (BBs) are highly effective in reducing CPVT-triggered arrhythmic events. However, some patients suffer from unacceptable BB side effects and might require strategies without a BB.

Objectives: This study sought to review the spectrum of and outcomes associated with BB-free treatment configurations in patients with CPVT enrolled in the International CPVT Registry.

Methods: From the Registry, patients with RYR2 variant-positive CPVT treated with a BB-free strategy for ≥6 months were included. Two treatment groups were defined: patients classified as very low risk and treated with intentional nontherapy (INT) and patients who needed to be treated but did not tolerate BBs and were treated with 3 different strategies.

Results: Overall, 100 of 1,017 patients (10%) were on a BB-free treatment strategy. There were 73 patients (33 female [42%]) in the INT group. In patients 66 (90%), INT was pursued after low-risk assessment in asymptomatic patients and absent or negligible stress test phenotype. Twenty-seven patients (22 female,81%) were treated using 3 different BB-free treatment strategies (flecainide monotherapy, n = 21; left cardiac sympathetic denervation monotherapy, n = 2; flecainide + left cardiac sympathetic denervation, n = 4). In total, 25 patients (93%) were previously treated with BBs. During a median follow-up of 6 years (interquartile range, 3-9 years), 2 patients (2%) had a CPVT-associated event.

Conclusions: Although nonselective BBs remain the cornerstone treatment for CPVT, 10% of patients with CPVT required a BB-free treatment strategy. After careful risk assessment, safe and effective BB-free treatment strategies can be configured.

Keywords: Beta-blockers; CPVT; side effects.