Abstract:OBJECTIVE: To evaluate the value of serum brain natriuretic peptide (BNP) in the diagnosis of hyperthyroid heart disease in children. METHODS: Fifty-eight children with hyperthyroidism were assigned to two groups according to their cardiac functions: hyperthyroid heart disease (n=28) and hyperthyroidism alone (n=30). Thirty healthy children served as the control group. Serum BNP level, left ventricular ejection fraction (LVEE) and E/A ratio were measured before and after treatment. The diagnostic value of BNP was evaluated in children with hyperthyroid heart disease. RESULTS: The serum BNP level in the hyperthyroid heart disease and the hyperthyroidism alone groups before treatment was significantly higher than that in the control group (P<0.05), while the LVEF and the E/A ratio were significantly lower than those in the control group (P<0.05). Serum BNP level was positively correlated with the TT3 (r=0.801, P<0.05) and TT4 levels (r=0.578, P<0.05) and negatively with the LVEF (r=-0.48, P<0.05) and the E/A ratio (r=-0.35, P<0.05) in the hyperthyroid heart disease group. The serum BNP, TT3 and TT4 levels in the hyperthyroid heart disease and the hyperthyroidism alone groups were reduced and the LVEF and the E/A ratio increased significantly three months after treatment (P<0.05). When serum BNP level of >323.62 pg/mL was proposed as a cutoff point, the sensitivity, specificity, positive predictive value and negative predictive value were 92.86%, 90.00%, 89.66% and 93.10% respectively for the diagnosis of hyperthyroid heart disease. CONCLUSIONS: BNP may serve as a reliable marker for the diagnosis of hyperthyroid heart disease in children. Serum BNP level along with the LVEF and the E/A ratio may be useful in the evaluation of the severity and the cardiac function in children with this disease.[Chin J Contemp Pediatr, 2009, 11 (8):631-634]