Pulmonary arterial hypertension (PAH) is an important determinant of morbidity and mortality in children. In this study, we aimed to investigate the value of brain natriuretic peptide (BNP) in a cohort of children with PAH, with respect to monitoring disease severity as assessed by hemodynamic and echocardiographic parameters.
We performed a prospective study to determine whether BNP varies over time in this population and whether these changes track with hemodynamic or echocardiographic parameters. The population included a group of 78 pediatric patients from January 2005 to April 2008. All patients had received a diagnosis of PAH and had serum BNP, catheterization, and echocardiographic variables collected longitudinally.
The median BNP level, for all observations, was 36 pg/mL (interquartile range, 18 to 76 pg/mL). There was no strong correlation found between commonly used echocardiographic or hemodynamic data and BNP. However, using a bivariate model, the change in BNP measurements over time significantly correlated with the change in the hemodynamic and echocardiographic parameters. Patients with a BNP value > 180 pg/mL had a decreased survival rate.
BNP could be a useful marker to monitor disease severity in pediatric PAH. We show that simple correlations between variables and BNP are not likely to illustrate its usefulness due to variations in the normative levels. Instead, we propose that patient BNP levels should be monitored over time, as changes in BNP within a patient are likely to be more informative.