Non-invasive diagnostics of blockage growth in the descending aorta-computational approach

Abstract

Atherosclerosis causes blockages to the main arteries such as the aorta preventing blood flow from delivering oxygen to the organs. Non-invasive diagnosis of these blockages is difficult, particularly in primary healthcare. In this paper, the effect of arterial blockage development and growth is investigated at the descending aorta on some possible non-invasive assessment parameters including the blood pressure waveform, wall shear stress (WSS), time-average WSS (TAWSS) and the oscillation shear index (OSI). Blockage severity growth is introduced in a simulation model as 25%, 35%, 50% and 65% stenosis at the descending aorta based on specific healthy control aorta data clinically obtained. A 3D aorta model with invasive pulsatile waveforms (blood flow and pressure) is used in the CFD simulation. Blockage severity is assessed by using blood pressure measurements at the left subclavian artery. An arterial blockage growth more than 35% of the lumen diameter significantly affects the pressure. A strong correlation is also observed between the ascending aorta pressure values, pressure at the left subclavian artery and the relative residence time (RRT). An increase of RRT downstream from the stenosis indicates a 35% stenosis at the descending aorta which results in high systolic and diastolic pressure readings. The findings of this study could be further extended by transferring the waveform reading from the left subclavian artery to the brachial artery. Graphical abstract

Prediction of Hemodynamic-Related Hemolysis in Carotid Stenosis and Aiding in Treatment Planning and Risk Stratification Using Computational Fluid Dynamics

“…The information obtained thanks to imaging methods allowed for the visualization of stenoses and the creation of accurate CFD simulation models. CFD simulations can be a valuable tool in a wide range of blood flows in the circulatory system [10,27,[63][64][65][66][67][68][69][70][71][72][73], providing valuable information for physicians. CFD can provide information on high shear stress [10,[63][64][65], which is one of the factors causing blood hemolysis, which negatively affects patients' health [74].…”

Aneurysm Rupture Prediction Based on Strain Energy-CFD Modelling

“…The mesh method was set to use Sweep with a mapped face of two and with an internal number of divisions equal to three. Based on our previous studies [22][23][24], the mesh quality was acceptable, which was considered a good mesh for these types of non-uniform geometries.…”

“…The fluid domain, shown in Figure 6b, is assumed to be an incompressible Newtonian fluid with a dynamic viscosity of 3.5 × 10 −3 and a density of 1050 kg/m 3 , as recommended by the literature [22][23][24]. The fluid domains were fixed at the inlet and outlet.…”

Intraluminal Thrombus Characteristics in AAA Patients: Non-Invasive Diagnosis Using CFD

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