Mathematical modelling of triple arterial stenoses

Area of Science:

• Biomedical Engineering
• Fluid Dynamics
• Computational Science

Background:

• Arterial stenoses, or narrowing, significantly impact blood flow dynamics.
• Understanding the hemodynamic effects of multiple stenoses in series is crucial for cardiovascular health.
• Previous models often simplify the complex interactions of multiple, sequential arterial blockages.

Purpose of the Study:

• To investigate the fluid dynamics of blood flow through three stenoses positioned in series within an artery.
• To analyze how varying degrees of stenosis severity influence pressure drop and flow patterns.
• To elucidate the compensatory mechanisms, such as pressure recovery, in multiply stenosed arterial segments.

Main Methods:

• Development of an axi-symmetric computational model for blood flow.
• Application of Newtonian fluid assumptions and the Navier-Stokes and continuity equations.
• Numerical solution using the Finite Element Method (FEM) with the FIDAP computational fluid dynamics (C.F.D.) package.

Main Results:

• Simulations reveal that the hemodynamic impact of milder stenoses is reduced when adjacent to more severe stenoses.
• Analysis of pressure drop profiles indicates significant alterations due to combined stenosis severity.
• Streamline plots demonstrate flow disturbances and recirculation zones influenced by stenosis configurations.
• Observed pressure recovery downstream of a severe stenosis when followed by a milder one.

Conclusions:

• The severity of arterial stenosis plays a dominant role in determining overall hemodynamic impact in series.
• The presence of multiple stenoses can lead to complex flow patterns and altered pressure gradients.
• The phenomenon of pressure recovery following a severe-to-mild stenosis sequence suggests a potential localized hemodynamic adaptation.