Flow behavior in a model of an end-to-side vascular graft

Abstract

Summary form only given. The results from canine experiments performed at the University of Chicago School of Medicine to provide information for an anastomosis geometry and flow waveforms are discussed. From these in vivo data, a scaled end-to-side anastomosis model was constructed. The model was placed in a flow system which could be operated under either steady or pulsatile flow conditions. Steady flow experiments were conducted at Reynolds numbers 1000, 650, and 200. The flow divisions between the proximal-distal exits were 0%-100%, 20%-80%, 50%-50%, and 100%-0%. Laminar flow patterns were observed for steady flow in all configurations except the 100%-0% flow division at Reynolds numbers 650 and 1000. Pulsatile experiments revealed that regions of low and oscillatory shear stress are present within an anastomosis along the opposite wall and near the distal exit. A region of high particle residence time was also discovered. The results from the flow visualization experiments suggest that the anastomotic regions susceptible to intimal hyperplasia are along the hood near the distal exit, along the floor of the native artery, and around the side walls of the sinus formed by the anastomosis. >