Incidence and Clinical Management of Supraventricular Arrhythmias in Patients With Catecholaminergic Polymorphic...

Smaller studies suggest supraventricular arrhythmias (SVAs) are common in patients with catecholaminergic polymorphic ventricular tachycardia (CPVT).

This study aimed to determine the incidence, type, and clinical management of SVAs observed within a large, single-center cohort of CPVT cases.

The electronic medical records of 206 patients (51% female; average age at diagnosis 21 ± 17 years) diagnosed clinically with CPVT between January 2000 and September 2023 were reviewed for electrocardiographic evidence of SVAs, including atrial fibrillation (AF), atrial flutter (AFL), atrial tachycardia (AT), and supraventricular tachycardia. SVAs were considered clinically significant when sustained for >30 seconds, with or without symptoms, ultimately necessitating clinical evaluation. SVA type, symptoms, and therapeutic efficacy were assessed.

Overall, 17 (8.3%) of 206 patients had evidence of an SVA (AF/AFL in 8, AT in 9, and supraventricular tachycardia in 1 [1 patient experienced both AT and AF/AFL]). The median age at SVA diagnosis was 28 years (Q1-Q3: 16-34 years). A total of 11 (65%) of 17 patients were symptomatic, 3 (27%) of whom experienced inappropriate shocks. All patients were trialed on antiarrhythmics. Owing to drug failure, intolerance, or patient/provider preference; 5 (29%) of 17 patients with SVAs underwent radiofrequency ablation. Notably, over a median follow-up duration of 11 months (Q1-Q3: 5-45 months), 1 SVA recurrence was observed in a patient treated medically.

In comparison with prior studies, the incidence of SVAs in this large, single-center CPVT cohort was substantially lower (8.3% vs 26%-35%). Although a larger multicenter study is needed to confirm, this study suggests that radiofrequency ablation durably treats CPVT-associated SVAs.