Chin KM, et al. - The prognostic value of N-terminal pro brain natriuretic peptide (NT-proBNP) thresholds in pulmonary arterial hypertension (PAH) was assessed in the GRIPHON trial, along with the response to selexipag according to these thresholds. Either selexipag or placebo was randomly received by patients in the GRIPHON trial. Based on two independent sets of thresholds, baseline tertiles (<271 ng/L; 271-1,165 ng/L; >1,165 ng/L) and 2015 ESC/ERS guideline cut-offs (<300 ng/L; 300-1,400 ng/L; >1,400 ng/L), participants were classified post-hoc into low, medium and high NT-proBNP subgroups. According to findings, NT-proBNP levels had prognostic relevance in PAH. A link was evident, for the first time ever, between NT-proBNP level and treatment response. Low, medium and high NT-proBNP categories were pertinent as part of the multiparametric risk evaluation tactic described in the ESC/ERS guidelines for managing PAH patients.