MP-PIC simulation of blood cell movement through a LAD with high stenosis

Abstract

Computed Tomography Angiography (CTA)-based computational fluid dynamics (CFD) has been proposed as a non-invasive method for the diagnosis of coronary artery stenosis. Although blood contains a huge amount of blood cells, it is still treated as a single-phase fluid in most of the current CFD models. This may result in inaccurate estimations of the pressure drop through a stenotic artery. In this study, a multiphase particle in cell (MP-PIC) model that includes particle movement in fluid, was proposed to simulate the pressure drop through coronary artery stenosis. A male patient with high stenosis at his left anterior descending (LAD) was chosen as a patient-specific model. Both conventional single-phase model and MP-PIC were used to simulate the pressure drop at this patient-specific model. Specifically, two types of spherical particles were used in MP-PIC to represent the non-spherical red blood cells. Particle 1 has the equivalent volume while particle 2 has the equivalent surface area of a red blood cell. The comparison of simulation results and clinical invasive measurement showed that the single-phase fluid model greatly underestimated the pressure drop; the predicted pressure drop is 6 mm Hg while the measured pressure drop is 20 mm Hg. Particle model 1 also underestimated the pressure drop (15 mm Hg) while particle model 2 overestimated the pressured drop (25 mm Hg). This study indicated that accurate estimation of pressure drop through artery stenosis requires reasonable multiphase models.