As reported, numerous variables, such as World Health Organization (WHO) functional class (FC) [3, 6, 8], 6-min walk distance (6MWD) [6, 8, 13, 14], right atrial pressure (RAP) [6, 13], cardiac index [13], pulmonary vascular resistance (PVR) [12, 14] and brain natriuretic peptide (BNP)/N-terminal pro-BNP (NT-proBNP) [8], have been reported to have prognostic value for CTEPH patients. Here, NPPB is linked to chronic thromboembolic pulmonary hypertension.