Determining the optimal cutoff values of plasma N-terminal pro-B-type natriuretic peptide levels for the diagnosis of heart failure in children of age up to 14 years.

BACKGROUND: Plasma N-terminal fragment of pro-B-type natriuretic peptide (NT-proBNP) is a biomarker of heart failure (HF). However, the optimal cutoff value of plasma NT-proBNP for the diagnosis of HF in children is unknown. The objective of this study was to determine the appropriate cutoff value of plasma NT-proBNP for the diagnosis of HF in children ≤14 years old. METHODS AND RESULTS: Plasma NT-proBNP concentrations were detected in pediatric HF patients using standard clinical assays. Patients were stratified into 4 groups by age: 0-1 year, 1-3 years, 4-7 years, and 8-14 years. Case-matched healthy children were recruited as control subjects. HF was diagnosed with the use of the modified Ross score. The optimal cutoff value of plasma NT-proBNP for the diagnosis of HF was determined by analyzing receiver operating characteristic (ROC) curves and the resulting sensitivity, specificity, and Youden index (J). In healthy children, plasma NT-proBNP level and age were negatively correlated (r = -0.739; P < .001). In HF patients aged 0-1 year, 1-3 years, 4-7 years, and 8-14 years, respectively, areas under the ROC curves were 0.795, 0.786, 0.783, and 0.696; 95% confidence intervals were 0.689-0.901, 0.669-0.903, 0.662-0.904, and 0.487-0.905; and J values were 0.715, 0.708, 0.706, and 0.679. Optimal cutoff values of plasma NT-proBNP for the diagnosis of HF were 502 ng/L, 456 ng/L, 445 ng/L, and.355 ng/L. CONCLUSIONS: Age-stratified analysis of plasma NT-proBNP levels in children provides new parameters for diagnosing HF.

[Clinical importance of preoperative measurement of plasma amino-terminal pro-B-type natriuretic peptide in infants with congenital heart disease].

OBJECTIVE: To define cut-off values of plasma amino-terminal pro-B-type natriuretic peptide (NT-ProBNP) for the diagnosis of congenital heart failure (CHF) and evaluate the importance of plasma NT-ProBNP measurement in the assessment of cardiac function prior to heart surgery in infants with congenital heart disease (CHD). METHODS: Plasma levels of NT-proBNP were measured in 120 infants with CHD before heart surgery and in 100 age-matched healthy infants between June 2010 and June 2013. The data were stratified based on the presence or absence of CHF in the whole group of CHD infants and on age (i.e., <1 year and ≥1 year) and time (i.e., before surgery) within the subgroup of CHF infants. RESULTS: Of the 120 infants with CHD, 41 met the criteria for CHF defined in the Ross Classification for Heart Failure in Infants.The cut-off values of plasma NT-ProBNP were ≥498 ng/L for infants of all ages, 557 ng/L for <1 year age group and 452 ng/L for ≥1 year age group, respectively, in the 41 CHF patients. In CHF infants, plasma NT-proBNP was significantly decreased after protecting of cardiac function (P<0.001). CONCLUSIONS: The cut-off values of plasma NT-ProBNP for CHF differ between infants <1 year and infants ≥1 year. Moreover, plasma NT-ProBNP can be used as an additional parameter in the preoperative assessment of cardiac function in CHD infants.