B-type natriuretic peptide predicts adverse cardiovascular events in pediatric outpatients with chronic left ventricular systolic dysfunction

Background - Plasma B-type natriuretic peptide (BNP) levels are elevated in adults with heart failure and correlate with functional classification and prognosis. The range and predictive power of BNP concentrations in children with chronic heart failure, however, are not known. Methods and Results - Whole blood BNP concentrations were measured in 53 consecutive patients with chronic left ventricular (LV) systolic dysfunction (biventricular hearts, ejection fraction < 50%, > 3 months since diagnosis). Children who had been hospitalized within 3 months before potential enrollment and those < 2 months or > 21 years of age were excluded. BNP concentrations were measured with the Triage assay (Biosite Diagnostics, Inc, San Diego, Calif). Echocardiographers and clinicians were blinded to BNP levels. An adverse cardiovascular event was defined as cardiac death, cardiac-related hospitalization, or listing for cardiac transplantation. The median age of patients with LV dysfunction was 9.3 years (interquartile range [IQR], 2.7 to 15.1 years). BNP levels were elevated in children with LV dysfunction compared with healthy controls (median, 78 pg/mL [IQR, 22 to 551 pg/mL] versus median, 7 pg/mL [IQR, 5 to 11 pg/mL]; P < 0.0001). Whole blood BNP concentrations were increased in patients who had a 90-day adverse cardiovascular event compared with those who did not (median, 735 pg/mL [IQR, 685 to 1510 pg/mL] versus median, 37 pg/mL [IQR, 14 to 92 pg/mL]; P < 0.001). Patients with a BNP concentration >= 300 pg/mL were at increased risk of death, hospitalization, or listing for cardiac transplantation (adjusted hazard ratio, 63.6; P < 0.0001). Conclusions - BNP concentrations are elevated in children with chronic LV systolic dysfunction and predict the 90-day composite end point of death, hospitalization, or listing for cardiac transplantation.