Hemodynamic effects of conduit position on systemic-to-pulmonary shunt: A Numerical study using virtual design

Abstract

The systemic-to-pulmonary shunt is a widely used palliative procedure in the therapy of congenital heart defect (CHD). Although it improved over the years, the anastomosis position of the conduit related to the control of pulmonary flow in the procedure is still one of the controversial issues. Based on patient-specific medical images, a three-dimensional (3D) vascular model was reconstructed in the present study. Four possible surgical positions of the conduit implantation for the systemic-to-pulmonary shunt were virtually devised by computer-aided design (CAD). Pulsatile simulations were done by the technique of computational fluid dynamics (CFD) to capture the physiological information of blood flow. The results indicated that higher pressure and wall shear stress were generated in the conduit. It may increase the risk of blood cell damage. While, the quantitative analysis showed that a relatively good balance of blood flow distribution and appropriate pressure drop between systemic and pulmonary circulations were achieved when the conduit was anastomosed at the innominate artery or subclavian artery than it was at the ascending aorta. The numerical study based on the virtual design is a useful approach for the preoperative prediction of local hemodynamics and provides more detailed information for the choice of patient-specific surgical design.