The level of plasma NT-proBNP in CTEPH was 1,809.52±1,532.16 pg/ml with a range of 19.79–5,909.00 pg/ml, and the Septal angle had a strong correlation with NT-proBNP (r=0.668, P=0.000). Here, NPPB is linked to chronic thromboembolic pulmonary hypertension.