Fig. 4From: Prevalence and risk prediction value of tricuspid regurgitation by echocardiography in precapillary pulmonary hypertensionA comparison of WHO heart function III or IV class (A), 6MWD (B) and NT-proBNP (C) among the four groups. TR: tricuspid regurgitation; WHO: World Health Organization; 6MWD: 6-minute walk distance; NT-proBNP: N-terminal pro-B-type natriuretic peptideBack to article page