Background: We aimed to assess whether levels of B-type natriuretic peptide (BNP)--an established marker of ventricular dysfunction--relate to functional status and outcome in children with idiopathic and associated pulmonary hypertension (PH).
Methods and results: BNP was measured in 50 children with PHT aged 8.4 +/- 5.1 years, all receiving PH specific therapies. Twenty-seven patients were diagnosed with idiopathic PH (IPAH), while 23 patients had associated PH [congenital heart disease (n = 17), lung disease (n = 4), other (n = 2)]. Functional status, six-minute walk test, echocardiographic and haemodynamic data were assessed. Mean BNP value was 143.5 +/- 236.2 pg/ml (range <5-1250). BNP correlated with Functional Class II, III, and IV (50.8 +/- 61.3, 196.9 +/- 291.2 and 280.0 +/- 276.5 respectively; p = 0.01), with echocardiographic assessment of right ventricular function (p < 0.01), hypertrophy (p < 0.01) and dilatation (p < 0.01). In IPAH BNP correlated with pulmonary arterial pressure and, on inhaled nitric oxide also with vascular resistance. During a mean follow-up of 14.0 +/- 7.5 months seven patients died, five underwent transplantation and two were listed for transplantation. Using ROC analysis, a BNP value >130 pg/ml predicted death or need for transplantation (p < 0.04). However, six children who died or were transplanted had a BNP value lower than this.
Conclusion: BNP correlated positively with functional status in children with pulmonary hypertension, but had limited sensitivity (57%) for predicting death or need for transplantation.