Fluid flow and plaque formation in an aortic bifurcation

Area of Science:

• Biomedical Engineering
• Fluid Dynamics
• Computational Biology

Background:

• Atherosclerosis, or plaque buildup, is a major cause of cardiovascular disease.
• Understanding the relationship between blood flow patterns and plaque formation is crucial for developing effective treatments.
• Branching arteries, like the aorta, are common sites for atherosclerotic lesions.

Purpose of the Study:

• To develop a computational model simulating blood flow and plaque formation in symmetric branching channels.
• To investigate the influence of hemodynamic factors such as Reynolds number, bifurcation angle, and lumen reduction on plaque deposition.
• To test hypotheses correlating critical wall shear stress levels with atheroma formation and progression.

Main Methods:

• A finite element model was developed to simulate steady laminar flow.
• The model analyzed velocity fields, pressure profiles, and wall shear stress distributions.
• A submodel was incorporated to simulate pseudo-transient plaque formation and deposition rates based on flow characteristics.

Main Results:

• The model identified reverse flow regions and characterized pressure and wall shear stress distributions.
• Plaque deposition was simulated in areas of critically low and high wall shear stress.
• Two conflicting hypotheses on critical wall shear stress and atheroma were tested, leading to a postulated solution.

Conclusions:

• The validated computer simulation model serves as a predictive tool for analyzing vascular changes.
• It can assess the impact of surgical reconstruction and atherosclerotic lesions on blood flow.
• The model aids in designing aortic bifurcations that minimize plaque formation.