Two 3D models of an arterio-venous graft, a connection between an artery and a vein as vascular access for hemodialysis, were studied. One model of a conventional straight loop graft, the other of a graft with helical configuration (e.g. SwirlGraft (Veryan Medical, London, UK)). The statement that the helical design reduces Intimal Hyperplasia (IH) formation was studied by evaluating low wall shear stress and high oscillatory shear stress zones next to the helicity flow index. The IH-inducing zones were reduced but were not eliminated and the helicity of the flow was increased. The statement that the SwirlGraft avoids stenosis should however be considered with care in clinical practice.