A mathematical analysis has been presented to study the effect of a mild stenosis on blood flow characteristics with the representation of blood by couple stress fluid. The equations governing the flow of the proposed model are solved and closed form expressions for the blood flow characteristics, namely, dimensionless resistance to flow and wall shear stress at maximum height of the stenosis a...

BACKGROUND AND PURPOSE Saccular intracranial aneurysm is a common disease that may cause devastating intracranial hemorrhage. Hemodynamics, wall remodeling, and wall inflammation have been associated with saccular intracranial aneurysm rupture. We investigated how saccular intracranial aneurysm hemodynamics is associated with wall remodeling and inflammation of the saccular intracranial aneurys...

The effects of an overlapping stenosis on blood flow characteristics in a narrow artery have been investigated. To account for the non-Newtonian behavior, blood has been represented by a Casson fluid. The equation describing the flow has been solved and the expressions for the flow characteristics, namely, the impedance, the wall shear stress, the shear stress at the stenosis throats and the sh...

Cyclic circumferential stretch and shear stress caused by pulsatile blood flow work in concert, yet are very different stimuli capable of independently mediating endothelial function by modulating eNOS expression, oxidative stress (via production of superoxide anion) and NO bioavailability. Porcine carotid arteries were perfused using an ex vivo arterial support system for 72 h. Groups we creat...

The distribution of the wall shear stress on the bed and sidewalls of an open channel receiving lateral inflow was obtained from experimental measurements of the distribution of the velocity in the viscous sublayer using a laser doppler velocimeter. The experiments were conducted in a 0.4 m wide by 7.5 m long flume. Lateral inflow was provided into the channel from above via sets of nozzles pos...

BACKGROUND Aortic stenosis (AS) leads to variable stress for the left ventricle (LV) and consequently a broad range of LV remodeling. The aim of this study was to describe blood flow patterns in the ascending aorta of patients with AS and determine their association with remodeling. METHODS AND RESULTS Thirty-seven patients with AS (14 mild, 8 moderate, 15 severe; age, 63±13 years) and 37 hea...

The effect of shear stress at the endothelium in the attenuation of the noradrenaline-induced constriction of the femoral vascular bed perfused at a constant blood flow was investigated in 16 anesthetized cats. It is known that the adrenergic vasoconstriction of the femoral vascular bed is considerably greater at a constant pressure perfusion than at a constant blood flow. This difference may d...

Vasoactive drugs are known to affect impedance (pressure/flow) and vessel wall motion in arteries. The nonlinear theory of oscillatory flow in straight elastic vessels indicates that wall shear rate is affected by changes in impedance phase angle and wall motion. To test whether wall shear rate depends on impedance phase angle and wall motion in vivo, wall shear rate was measured in the abdomin...