Background and objective

The accumulation of plaque in the coronary artery of the human heart restricts the path of blood flow in that region and leads to Coronary Artery Disease. This study's goal is to present the pulsatile blood flow conduct through four different levels of constrictions, i.e., healthy, 25%, 50%, and 75% in human left coronary arteries.

Methods

Using CT scan data of a healthy person, the two-dimensional coronary model is constructed. A non-Newtonian Carreau model is used to study the maximum flow velocity, streamline effect, and maximum Wall Shear Stress at the respective constricted areas over the entire cardiac cycle. Finite Volume Method is executed for solving the governing equations. The fluctuating Wall Shear Stress (WSS) at different levels was assessed using Computational Fluid Dynamics (CFD).

Results

The comparative study of the diseased arteries showcases that at the systolic phase, the 75% blocked artery attains the maximum velocity of 0.14 m/s and 0.53 m/s at t=0.005 s and t=0.115 s, respectively. While the maximum velocity takes a significant drop at t=0.23 s and t=0.345 s, this marks the diastolic phase. The streamline contour showcased the blood flow conduct at different phases of the cardiac cycle. At the peak systolic phase, a dense flow separation was observed near the blocked regions. It highlights the disturbed flow in that particular region. The most severely diseased artery acquires the maximum WSS of 18.81 Pa at the peak systolic phase, i.e., at t=0.115 s.

Conclusions

The computational study of the hemodynamic parameters can aid in the early anticipation of the degree of the severity of the diseased arteries. This study, in a way, could benefit doctors/surgeons to plan an early treatment/surgery on the grounds of the severity of the disease. Thus, a before time prognosis could restrain the number of deaths caused due to Coronary Artery Disease.

中文翻译：

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通过收缩的人类左冠状动脉进行血液血液动力学的数值计算：脉冲模拟。

背景和目标

人心脏冠状动脉中斑块的积聚限制了该区域的血流路径，并导致了冠状动脉疾病。这项研究的目的是通过四个不同水平的收缩来显示脉动血流的传导，即健康的人左冠状动脉中分别为25％，50％和75％。

方法

Using CT scan data of a healthy person, the two-dimensional coronary model is constructed. A non-Newtonian Carreau model is used to study the maximum flow velocity, streamline effect, and maximum Wall Shear Stress at the respective constricted areas over the entire cardiac cycle. Finite Volume Method is executed for solving the governing equations. The fluctuating Wall Shear Stress (WSS) at different levels was assessed using Computational Fluid Dynamics (CFD).

Results

The comparative study of the diseased arteries showcases that at the systolic phase, the 75% blocked artery attains the maximum velocity of 0.14 m/s and 0.53 m/s at t=0.005 s and t=0.115 s, respectively. While the maximum velocity takes a significant drop at t=0.23 s and t=0.345 s, this marks the diastolic phase. The streamline contour showcased the blood flow conduct at different phases of the cardiac cycle. At the peak systolic phase, a dense flow separation was observed near the blocked regions. It highlights the disturbed flow in that particular region. The most severely diseased artery acquires the maximum WSS of 18.81 Pa at the peak systolic phase, i.e., at t=0.115 s.

Conclusions

血液动力学参数的计算研究可以帮助早期预测患病动脉的严重程度。从某种意义上说，这项研究可以使医生/外科医生从疾病的严重程度出发计划早期治疗/手术。因此，预先的预后可以抑制由于冠状动脉疾病引起的死亡人数。