Haemodynamic of blood flow through stenotic aortic valve

Abstract

Aortic valve (AV) stenosis is described as the deposition of calcium within the valve leaflets. With the growth of stenosis, haemodynamic, mechanical performances of the AV and blood flow through the valve are changed. In this study, we proposed two fluid–structure interaction (FSI) finite element (FE) models. The hyperelastic material model was considered for leaflets tissue. The leaflet tissue was considered stiffer in stenotic valve than the healthy leaflets because of its calcium content. Therefore, the valve could not open completely and this led to a decrease in the orifice area of the valve. The orifice area decreased from 2.4 cm2 for the healthy AV to 1.4 cm2 for the stenosis case. Mean pressure gradient increased in mid systole and the axial velocity experienced a three times increment in magnitude. Higher blood shear stress magnitudes were observed in stenotic valve due to the structure of the leaflet. In addition, strain concentration and higher stress values were observed on the leaflets in stenotic valve and the effective stress was greater than healthy case. In addition, pressure and velocity results were consistent with the echocardiography data literature. We have compared the performance of healthy and stenotic AV models during a complete cardiac cycle. Although improvements are still needed, there was good agreement between our computed data and other published studies.