Abstract: The influence of the relative intraatrial anastomoses positions of IVC to SVC on the hemodynamic performance is studied for surgical planning.First,to provide a theoretical basis for the clinical treatment,a 3D geometry model including pulmonary artery (PA),left (LPA) and right (RPA) pulmonary arteries,SVC,and IVC is reconstructed from medical images.Second,based on virtual environment,three surgical option models are sculptured according to the relative positions between the IVC and the SVC in a free form deformation.Finally,numerical simulations of hemodynamics are carried out.The flow structures,total pressures,power losses,and flow splits are analyzed to evaluate the optimal options.Results show that the right-IVC model performs a less power loss and relative balanced flow split,which may be the optimal option.