Computer-Simulated Fluid Dynamics of Arterial Perfusion in Extracorporeal Circulation: From Reality to Virtual Simulation

Abstract

Atheroembolism due to aortic manipulation remains an unsolved problem in surgery for thoracic aortic aneurysm. The goal of the present study is to create a computer simulation (CS) model with which to analyze blood flow in the diseased aorta. A three-dimensional glass model of the aortic arch was constructed from CT images of a normal, healthy person and a patient with transverse aortic arch aneurysm. Separately, a CS model of the curved end-hole cannula was created, and flow from the aortic cannula was recreated using a numerical simulation. Comparison of the data obtained by the glass model analyses revealed that the flow velocity and the vector of the flow around the exit of the cannula were similar to that in the CS model. A high-velocity area was observed around the cannula exit in both the glass model and the CS model. The maximum flow velocity was as large as 1.0 m/s at 20 mm from the cannula exit and remained as large as 0.5 to 0.6 m/s within 50 mm of the exit. In the aortic arch aneurysm models, the rapid jet flow from the cannula moved straight toward the lesser curvature of the transverse aortic arch. The locations and intensities of the calculated vortices were slightly different from those obtained for the glass model. The proposed CS method for the analysis of blood flow from the aortic cannulae during extracorporeal circulation can reproduce the flow velocity and flow pattern in the proximal and transverse aortic arches.