Flow patterns in three-dimensional porcine epicardial coronary arterial tree

Area of Science:

• Cardiovascular physiology
• Biomedical engineering
• Computational fluid dynamics

Background:

• Epicardial coronary arteries exhibit complex 3D branching patterns.
• Understanding blood flow dynamics is crucial for explaining atherosclerotic plaque formation.

Purpose of the Study:

• To conduct a detailed hemodynamic analysis of a left anterior descending (LAD) arterial tree.
• To identify flow disturbances and their relationship with atherosclerotic-prone regions.

Main Methods:

• Utilized a 3D finite element method for hemodynamic analysis.
• Incorporated computed tomography (CT) scans for arterial geometry.
• Measured inlet flow velocity and estimated outlet pressure boundary conditions.

Main Results:

• Low wall shear stress (WSS) and high oscillatory shear index (OSI) correlate with disturbed flow patterns (stagnated, reversed flow) at bifurcations.
• High time-averaged WSS gradient (WSSG) was observed at flow dividers.
• Low WSS and high OSI showed a power-law relationship and were amplified by larger diameter ratios and higher flow rates.

Conclusions:

• Disturbed flow patterns, characterized by specific WSS, WSSG, and OSI levels, explain focal atherosclerotic-prone regions.
• Arterial diameter ratio significantly impacts flow dynamics and atherogenesis.
• Findings provide insights into the physical mechanisms underlying atherosclerosis development.