Fig. 1From: Exhaled nitric oxide is not a biomarker for idiopathic pulmonary arterial hypertension or for treatment efficacyN-terminal pro b-type natriuretic peptide (NT-ProBNP) changes in the three WHO functional classes before and after treatment. Levels of NT-ProBNP before and after treatment in class I (n = 8 subjects), II (n = 17 subjects) and III (n = 11 subjects). Data are reported as mean ± semBack to article page