The patients were classified into the non-PAH (mPAP < 25 mmHg, n = 37) or PAH (mPAP ≥ 25 mmHg, n = 15) group based on mPAP measured by RHC. No significant differences in age, gender, body mass index, log brain natriuretic peptide, or carbon monoxide diffusion capacity by body surface were found between the non-PAH and PAH groups, although, significant differences in pulmonary arterial wedge pressure (p < 0.0001) and pulmonary vascular resistance were found (p = 0.003) (Table 1). Meanwhile, no significant differences in conventional echocardiographic parameters were found between the non-PAH group, PAH group and controls, but post-exercise blood pressure and heart rate were higher in the non-PAH and PAH groups than the controls