CFD Analysis of Diameter Mismatch Effects on Hemodynamics and Thrombosis Risk in Saphenous Vein Grafts

A digital arterial disease in the upper extremity is uncommon compared to arterial disease in the lower extremity. A microvascular anastomosis is performed as a vascular reconstruction. However, mismatching in size between end-to-end anastomosis of venules-arterioles internal diameter. might cause blockage in the new vascular reconstruction region. In a previous study, internal diameter discrepancy in vessel size (small-large or vice versa) caused abnormal blood flow behavior. Then it will initiate the thrombosis formations and be supported by clinical theory. This study aims to analyze the blood flow behavior through mismatching in size anastomosis models and their flow patterns that might affect the initiation of thrombus formation in venule models. A three-dimensional computational fluid dynamic (3-D CFD) method is employed to investigate blood flow velocity, vascular resistance, and wall shear stress (WSS) on ideal straight (well matched between the internal diameter of the venule and recipient arteriole) and internal diameter mismatched anastomosis models. In this experiment, we expect that steady-state laminar blood flow demonstrates abnormal flow patterns in mismatched internal diameter anastomosis models compared to an ideal matched model. In conclusion, any abnormal blood flow pattern will initiate the formation of a thrombus and reduce the anastomosed venule-arterioles survival.