Shear-Induced Platelet Activation in Tortuous Coronary Artery: A Numerical Study

High fluid shear stresses (FSSs) were observed in tortuous coronary arteries, especially during the strenuous exercise condition. Whether these high FSSs would enhance the shear-induced platelet activation is still unknown. A computational fluid dynamics (CFD) study was conducted to evaluate the impact of coronary tortuosity (CT) on the shear-induced platelet activation during various conditions. A patient-specific left anterior descending (LAD) coronary artery model (CT model) and the corresponding non tortuous model (nCT model) were reconstructed to perform three-dimensional CFD analysis. Lagrangian particle analysis was performed to further obtain the platelet activation state (PAS) of the platelet-like particles. No significant difference was observed between CT and nCT models on the PAS values reached by the platelet-like particles at all simulated conditions. PAS values for particles within both CT and nCT models were decreased during exercise conditions, as compared to those during the rest condition. These results confirmed that CT could not enhance the platelet activation even with extreme high FSSs existing at bend sections during the strenuous exercise condition, and the results also implied that high FSSs might not be the critical factor leading to the platelet activation during the strenuous exercise for persons without the coronary obstructive.