Diagnostic role of N-terminal pro-B-type natriuretic peptide (NT-proBNP) in pediatric syncope in the emergency department: a prospective study.

Cardiac syncope in children is a critical risk and demands a prompt, accurate diagnosis. This study aimed to elucidate the diagnostic efficacy and clinical relevance of N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels in distinguishing between cardiac and non-cardiac syncope in children. A prospective study was conducted in a tertiary pediatric emergency department (ED), enrolling patients who were diagnosed with syncope. Conventional cardiac biomarkers, serum NT-proBNP, telecardiography, and 12-lead electrocardiography were performed. All patients underwent echocardiography, while TILT testing and 24-h Holter monitoring were performed by a pediatric cardiologist in a subset of patients. Electroencephalography (EEG) was performed after cardiac syncope had been ruled out and the patient had been evaluated by a pediatric neurologist. Overall, 197 patients and 50 healthy children were included. Cardiac etiology was identified in 8.6% of patients, while vasovagal, idiopathic, neurologic, orthostatic, and psychogenic syncope accounted for 27.9%, 28.9%, 15.2%, 5.6%, and 7.6% of cases, respectively. The TILT test was performed on only 19.8% of patients, and 46.2% were positive. The median serum NT-proBNP levels were 437.4 ng/L, 44.5 ng/L, and 37.1 ng/L in children with cardiac syncope, non-cardiac syncope, and healthy children (p < 0.001, p = 0.008, and p = 0.971, respectively). The optimum diagnostic cut-off point for cardiac syncope in 7-18-year-old children was 145.0 ng/L, the AUROC was 0.761 (95% CI:0.589-0.934), sensitivity 64.3%, specificity 98.2%, PPV 75.0%, and NPV 97.1%. Conclusion: Serum NT-proBNP levels have been shown to be a promising biomarker for predicting cardiac syncope in children. An NT-proBNP level above 145 ng/L may help identify children at increased risk of a cardiac etiology.