Fluid-structure interaction analysis of pulsatile flow within a layered and stenotic aorta

Area of Science:

• Biomedical Engineering
• Fluid Dynamics
• Computational Mechanics

Background:

• Aortic stenosis, a narrowing of the aorta, significantly alters blood flow dynamics and biomechanical stresses.
• Understanding the fluid-structure interaction (FSI) in a stenotic aorta is critical for elucidating disease progression.

Purpose of the Study:

• To investigate the hemodynamic characteristics and stress distribution in layered, stenotic aortas.
• To clarify the influence of stenosis morphology (symmetrical vs. unsymmetrical) and severity on aortic responses.

Main Methods:

• Utilized computational modeling incorporating in-vivo pulsatile waveforms.
• Performed fully fluid-structure interaction (FSI) analysis between the layered elastic aorta and blood.
• Introduced symmetrical and unsymmetrical stenosis models to analyze varying stenotic ratios.

Main Results:

• Abnormal blood flow patterns, including whirlpool formation, were observed in stenotic regions.
• Maximum wall shear stresses (WSS) concentrated at the stenosis throat, increasing with stenotic ratio.
• Unsymmetrical stenosis led to localized peak Von Mises stresses and varied shear stress distribution across aortic layers.

Conclusions:

• Stenosis morphology and severity critically influence hemodynamic alterations and stress distribution within the aorta.
• Findings offer insights into the pathogenesis and progression of diseases such as arteriosclerosis and aortic dissection.
• The study highlights the importance of considering FSI in stenotic aorta biomechanics.