Choi Hyoung Gwon, Vo Duc Huynh, Yoo Jung Yul, Ha Sang Truong, Lee Kwan Yong
Department of Mechanical and Automotive Engineering, Seoul National University of Science and Technology, Seoul, Republic of Korea.
Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea.
Sci Rep. 2025 Apr 8;15(1):11977. doi: 10.1038/s41598-025-89427-w.
The occurrence of atherosclerotic lesions in the coronary bifurcation tends to progress confined to specific areas depending on blood flow patterns. We conducted a numerical investigation into the three-dimensional bifurcation flow of the coronary artery, focusing on a side branch vessel branching off at a specified bifurcation angle. This study examined the impact of the bifurcation angle on flow characteristics around the bifurcation region, including wall shear stress, static pressure, the size of the reverse flow zone, and the flow rate distribution to the side branch vessel. Unsteady pulsatile flow has been considered at Re = 300 assuming blood as a Newtonian fluid. Our numerical results indicate that as the bifurcation angle increases, the pressure drop between the inlet and outlet increases, while the flow rate to the side branch vessel decreases. Additionally, in our study, a reverse flow zone near the outer wall of the side branch was observed, and it was found that the reverse flow becomes stronger as the bifurcation angle increases due to the lower momentum of blood near the outer wall and the central part of the side branch vessel. The height of reverse flow zone of the side branch rapidly increases as the bifurcation angle increases up to about 60 degrees and then mildly saturates as the bifurcation angle increases. Flow stagnation in the reverse flow zone of the side branch may promote platelet aggregation and lipid deposition, accelerating the formation of atherosclerotic plaques.
冠状动脉分叉处动脉粥样硬化病变的发生往往会根据血流模式局限于特定区域发展。我们对冠状动脉的三维分叉血流进行了数值研究，重点关注以特定分叉角度分支的侧支血管。本研究考察了分叉角度对分叉区域周围血流特性的影响，包括壁面剪应力、静压、逆流区大小以及流向侧支血管的流量分布。假设血液为牛顿流体，在雷诺数Re = 300时考虑了非定常脉动流。我们的数值结果表明，随着分叉角度的增加，进出口之间的压降增加，而流向侧支血管的流量减少。此外，在我们的研究中，观察到侧支血管外壁附近存在一个逆流区，并且发现由于侧支血管外壁和中心部分附近血液的动量较低，随着分叉角度的增加，逆流变得更强。随着分叉角度增加到约60度，侧支血管逆流区的高度迅速增加，然后随着分叉角度的增加而略有饱和。侧支血管逆流区的血流停滞可能会促进血小板聚集和脂质沉积，加速动脉粥样硬化斑块的形成。
