Blood flow through a stenosed catheterized artery: Effects of hematocrit and stenosis shape

The problem of blood flow through a narrow catheterized artery with an axially nonsymmetrical stenosis has been investigated. Blood is represented by a two-phase macroscopic model, i.e., a suspension of erythrocytes (red cells) in plasma (Newtonian fluid). The coupled differential equations for both fluid (plasma) and particle (erythrocyte) phases have been solved and the expression for the flow characteristics, namely, the flow rate, the impedance (resistance to flow), the wall shear stress and the shear stress at the stenosis throat have been derived. It is found that the impedance increases with the catheter size, the hematocrit and the stenosis size (height and length) but decreases with the shape parameter. A significant increase in the magnitude of the impedance and the wall shear stress occurs even for a small increase in the catheter size. The flow resistance increases and the shear stress at the stenosis throat decreases with the increasing catheter size and assume an asymptotic value at about the catheter size half of the artery size.