Flow studies in three-dimensional aorto-right coronary bypass graft system

Area of Science:

• Cardiovascular fluid dynamics
• Biomedical engineering
• Computational modeling

Background:

• Coronary artery bypass grafting (CABG) is a critical procedure for treating coronary artery disease.
• Graft patency, the long-term success of the bypass, is influenced by various factors, including hemodynamics.
• Understanding blood flow patterns within bypass grafts is essential for improving surgical outcomes.

Purpose of the Study:

• To investigate the fluid dynamics of blood flow in a aorto-right coronary bypass model.
• To analyze velocity and wall shear stress distributions within the graft and surrounding arteries.
• To identify regions of disturbed flow that may impact graft performance and contribute to arterial disease.

Main Methods:

• Three-dimensional computational fluid dynamics (CFD) simulations were performed using FLUENT 6.0.1.
• Simulations modeled blood flow in coronary artery-bypass systems during specific cardiac cycle intervals.
• Input data included physiological flow rates from the aorta, derived from prior studies.

Main Results:

• Calculated flow-field distributions of velocity and wall shear stress at four cardiac cycle instants (two systole, two diastole).
• Visualized velocity vectors and wall shear stress within the aorto-graft-coronary arterial domain.
• Identified disturbed flow patterns primarily at the graft entrance (aorta to graft) and exit (graft to coronary artery).

Conclusions:

• Disturbed flow patterns at graft junctions are significant factors influencing coronary artery perfusion.
• These hemodynamic insights can help elucidate the link between fluid dynamics and arterial diseases.
• Understanding these factors is crucial for improving graft patency and long-term CABG success.