Three-dimensional simulation of coronary artery bypass grafting with the use of computational fluid dynamics.

In search of an optimal anastomosis conformation in coronary artery bypass grafting surgery and flow visualization, three-dimensional simulation of the anastomosis has been developed with the use of computational fluid dynamics. To simulate the surgery, a Y-figure model with proximal stenosis was developed in three cases according to angles ranging from 10 degrees to 30 degrees. The boundary condition of velocity and flow of the model were given based on the average velocity and flow of coronary artery measured intraoperatively. Using this information, the fluid dynamics of three models were calculated by commercial computation fluid dynamics code. The convergent results showed the least recirculating jet in the 10 degrees anastomosis without back flow into the graft. The total energy loss in the field was most affected in 30 degrees anastomosis. The wall shear stress profile showed maximum values at the heel region where recirculating jet takes place. This simulation suggests that the more acute is the angle of anastomosis, the smaller is the energy loss. Based on this phenomenon, surgery should therefore be designed to obtain as acute an angle as possible in light of the fluid dynamics.