Correlations between B-type natriuretic peptide levels and nongeometric echocardiographic parameters in pediatric cardiomyopathies

Abstract

B-type natriuretic peptide is a conventional cardiac biomarker in adult cardiology, however, it is not commonly used in pediatric cases. After introducing B-type natriuretic peptide measurements in pediatric patients for the evaluation of systemic right ventricular function, the authors wanted to evaluate the value of plasma B-type natriuretic peptide and compare the results with systolic and diastolic myocardial parameters obtained with conventional echocardiography and tissue Doppler imaging in children with cardiomyopathy. Between 2007 and 2010, 58 plasma B-type natriuretic peptide measurements were performed in 32 children (dilated cardiomyopathy in 20, hypertrophic cardiomyopathy in 10 and non-compacted cardiomyopathy in 2 cases). The age of the patients was 7.9±6.6 years (mean±SD). Plasma B-type natriuretic peptide was measured using an electrochemiluminescent assay within one day from echocardiographic evaluation. As compared to normal values, children with the 3 types of cardiomyopathies showed significant differences in plasma B-type natriutretic peptide levels (dilated cardiomyopathy vs normal, p<0.001; hypertrophic cardiomyopathy vs. normal, p<0.01; non-compacted cardiomyopathy vs. normal, p<0.001). There was a significant negative correlation (r = -0,63; p<0,01) between B-type natriuretic peptide levels (range, 12-7002 ng/L; mean±SD, 1531±1750 ng/L) and linEF values (range, 4-50%; mean±SD, 22.5±13%). For B-type natriuteric peptide, a cut-off point of 1000 ng/L proved to differentiate significantly decreased linEF values (<17%). B-type natriuretic peptide levels significantly correlated with left ventricular end-diastolic diameter (r = 0.899; p<0.001), with left ventricular anular S wave parameters (r = 0.689; p<0.001) and with E/e ratio (r = 0.43; p<0.05). B-type natriuretic peptide measurements are recommended in all types of cardiomyopathies.