Abstract: AIM:To explore the changes of right ventricular function in patients with pulmonary hypertension (PH) using time intervals of right ventricular motion from pulsedwave tissue Doppler imaging (PWTDI). METHODS: One hundred and fifty PH patients and 60 agematched controls were studied. Patients were divided into three PH groups according to their PH level. PWTDI was used to record the anterior tricuspid annulus motion in the apical fourchamber view. Parameters of time intervals including electromechanical delay (EMD), isovolumetric contraction time (ICT), preejection period (PEP), ejection time (ET), isovolumetric relaxation time (IRT) and filling time (FT) were measured and Tei index was calculated. Data were analyzed with statistical software. RESULTS: Compared with control group, IRT in mild PH group was prolonged (P<001), and IRT was prolonged and FT shortened in moderate PH group (P<001). In severe PH group, IRT, ICT and PEP were prolonged, whereas ET and FT were shortened (P<001). Tei index in PH groups all significantly increased compared with control group (P<001). Statistical differences in IRT and FT were found between severe group and mild group and moderate group (P<005). ICT, PEP, ET and Tei index were significantly different between severe PH group and mild PH group (P<005). No significant difference in EMD was observed among the three PH groups and control group. CONCLUSION: PH leads to the dysfunction of the right ventricle. Right ventricular diastolic dysfunction happens in the early stage of PH and precedes systolic dysfunction in PH patients.