OBJECTIVETo study the hemodynamics of the pulmonary artery (PA) in pulmonary artery hypertension (PAH).

METHODSWith combined clinical hemodynamic measurements and CT data, the 3D model of PA and its branches was reconstructed to obtain the real 3D geometric structure of PA and its branches. Computational fluid dynamics (CFD) simulation was carried out for the reconstructed 3D geometric model of the PA and its branches with Womersley velocity as main pulmonary entrance conditions; then hemodynamic parameters of the PA and its branches in cardiac cycle were calculated and the changes of flow field, pressure, wall shear stress (WSS) at different times, and its impact on physiological processes were analyzed.

RESULTSimulation showed that the pressure of the main PA and the branches of the left and right PA was higher in the systolic period than that in the diastolic period; especially, the that of right PA and its interlobular artery was significantly higher than that of the left. The blood flow velocity of the main PA and its branches of right and left PA was significant different, the velocity was much higher at the distal of the right PA than that at the left. High WSS field formed at the proximal of the right PA before the branches during the systolic.

CONCLUSIONThe right PA at the proximal and lower lobe artery are affected by much larger pressure and change firstly, so the change of morphological and functional of theses segments will be have more important value to prompt existence of the early PAH.