Angular difference in human coronary artery governs endothelial cell structure and function.

Area of Science:

• Cardiovascular Biology
• Biomedical Engineering
• Hemodynamics

Background:

• Atherosclerosis primarily develops at blood vessel branch points with oscillatory/turbulent flow and low wall shear stress (WSS).
• Vascular endothelial functions are critically dependent on biomechanical forces like WSS.

Purpose of the Study:

• To investigate how blood vessel bifurcation angles influence hemodynamic alterations.
• To examine the associated changes in endothelial function in response to varying bifurcation angles.

Main Methods:

• Computer-aided design (CAD) of human coronary artery bifurcations with varying angles.
• 3D printing of these designs.
• Computational fluid dynamics (CFD) analysis to assess hemodynamics.
• Biochemical marker detection (eNOS, ICAM1) and monocyte attachment assays in endothelial cells (EC).

Main Results:

• Larger branching angles resulted in more complex turbulent/oscillatory hemodynamics.
• Minimum WSS was observed at branching points with larger angles.
• Significant alterations in eNOS, ICAM1, and monocyte attachment were recorded in ECs at a 60° branching angle, correlating with lower WSS.

Conclusions:

• Blood vessel branching angle is a critical factor in determining atherogenic-endothelial dysfunction.
• Hemodynamic forces, particularly WSS, at bifurcations are significantly influenced by branching angle.
• Understanding these relationships can inform strategies for preventing atherosclerosis.