Curvature is everywhere, in man or nature made devices. Its implication on physiological flows may be as important as other inertial or viscous effects. Relatively to an otherwise straight vessel, the so called centrifugal forces induce secondary flow that modify the whole flow structure and give rise to Dean vortices. Since the pioneering work of Dean many fundamental and applied investigations were performed. More specifically, in the blood dynamics studies, experimental and numerical simulations were also achieved. On the other hand many studies dealt with stenoses or aneurysms mainly situated in otherwise straight vessels. Thus the coupling between the global curvature effects and local section variations due to stenoses or aneurysms is not enough investigated. In the present work we will quantify how the impact of a stenosis or an aneurysm is modified when it occurs in a curved vessel compared to when it is located in a straight environment
