Altering end-to-side anastomosis junction hemodynamics: the effects of flow-splitting.

The long-term patency rate of peripheral artery bypass grafts remains low. Several theories exist which attempt to explain the disease forming mechanisms at the disease prone distal junction of the bypass graft. Common to these theories is that abnormal hemodynamics and wall mechanics contribute to the development of disease at the junction. This study describes a means by which the hemodynamics in the end-to-side anastomosis can be altered by inserting a flow-split into the junction, the function of which is to divert the flow away from the artery bed and toward the sidewalls. Velocity vectors through the junction are significantly altered, and artery centreline WSS magnitudes decrease by up to 36% during the deceleration phase of the flow pulse. Corresponding wall shear stress gradients are found to decrease by 49%. However, locations along the artery sidewall have been identified with increased WSS. It is possible to significantly alter junction hemodynamics using a flow-splitter.