Serum NT-proBNP Concentrations in Pediatric Patients with a History of Idiopathic Cardiac Arrhythmias: A Pilot Study

Diagnosis and management of pediatric cardiac arrhythmias is challenging due to heterogeneous clinical presentation and limited availability of validated biomarkers. N-terminal pro-B-type natriuretic peptide (NT-proBNP) is a well-established marker of myocardial stress; its role in pediatric arrhythmias has not been fully elucidated. This pilot study included 26 children and adolescents with a history of idiopathic ventricular arrhythmias (VAs, n = 17) or supraventricular tachycardia (SVT, n = 9) and 20 hospital-based controls without arrhythmias. Serum NT-proBNP was measured by ELISA. Group differences were tested with the Mann–Whitney U test and correlations with Spearman’s coefficient. NT-proBNP concentrations were significantly higher in pediatric patients with a history of cardiac arrhythmias than in controls, with the difference remaining statistically significant for the VAs subgroup. The treated patients had significantly lower levels than the untreated individuals. NT-proBNP showed no significant associations with age, sex, echocardiography, or other laboratory parameters. In the VAs subgroup, NT-proBNP was moderately negatively correlated with baseline QRS duration. Given a limited patient population, these findings represent a pilot exploratory analysis. NT-proBNP should be considered a supportive biomarker reflecting functional myocardial strain rather than a stand-alone diagnostic tool for pediatric arrhythmia classification.