NPPB and chronic thromboembolic pulmonary hypertension: Notably, using ROC analysis, we observed a serum NT-proBNP level of ≥1,433 pg/ml has a similar value to a Septal angle of ≥67.5° for predicting the PVR ≥1,000 (dynes.sec.mm−5) in PH and CTEPH patients, suggesting the predictive value of a Septal angle ≥67.5° may also be used to evaluate the long-term prognosis in PH patients.