Clinical implications of serial serum N-terminal prohormone brain natriuretic peptide levels in the prediction of outcome in children with dilated cardiomyopathy

Abstract

N-terminal prohormone brain natriuretic peptide (NT-proBNP) is known to be valuable as a prognostic marker for the management of heart failure. This study aimed to assess the serial changes of serum NT-proBNP levels as a prognostic factor for outcomes of pediatric dilated cardiomyopathy (DC). A retrospective study reviewed echocardiographic measurements and serum NT-proBNP levels obtained at the time of diagnosis, 3 and 6 months after diagnosis, and at the last follow-up in 68 children with DC. They were classified into 3 groups according to the last follow-up of the left ventricular (LV) function: group I (n = 37) with LV fractional shortening (FS) ≥25%, group II (n = 15) with 10% ≤ LVFS < 25%, and group III (n = 16) with LVFS <10% or cardiac death. The median age at diagnosis was 30 months and median duration of follow-up was 45 months (range 8 to 108 months). The origin of DC varied. Serial serum NT-proBNP levels showed statistically significant differences among the 3 groups. Although initial levels of serum NT-proBNP at diagnosis were not different from each other, group III maintained a higher NT-proBNP level throughout the duration of the follow-up. On multivariate Cox analysis, only the NT-proBNP level at 3 months was a significant predictor of an adverse outcome (hazard ratio 2.012, p = 0.028). The percent changes of NT-proBNP from diagnosis were not significant. Patients with DC with a serum NT-proBNP level ≥681 pg/ml at 3 months after diagnosis showed an increased risk of severe LV dysfunction or cardiac death (p <0.001, area under the curve = 0.846). In conclusion, the level of NT-proBNP in serum at 3 months after diagnosis could predict an adverse outcome in pediatric DC and could be used as a guide for long-term treatment plans.