Two 3D computer models of an arterio-venous graft, used as vascular access for hemodialysis were studied: a conventional straight loop graft and a graft with helical configuration. The hypothesis that the helical design would reduces Intimal Hyperplasia formation was studied by evaluating zones of low wall shear stress and high oscillatory shear stress. These zones, considered to promote IH, were reduced in the helical configuration but were not eliminated. The statement that the SwirlGraft avoids stenosis should therefore be considered with care in clinical practice. Keyword: artificial organs.