Studying the formation and stability of atherosclerotic plaques in the hemodynamic field is essential for understanding the growth mechanism and preventive treatment of atherosclerotic plaques. In this paper, based on a multiplayer porous wall model, we established a two-way fluid–solid interaction with time-varying inlet flow. The lipid-rich necrotic core (LRNC) and stress in atherosclerotic plaque were described for analyzing the stability of atherosclerotic plaques during the plaque growth by solving advection–diffusion–reaction equations with finite-element method. It was found that LRNC appeared when the lipid levels of apoptotic materials (such as macrophages, foam cells) in the plaque reached a specified lower concentration, and increased with the plaque growth. LRNC was positively correlated with the blood pressure and was negatively correlated with the blood flow velocity. The maximum stress was mainly located at the necrotic core and gradually moved toward the left shoulder of the plaque with the plaque growth, which increases the plaque instability and the risk of the plaque shedding. The computational model may contribute to understanding the mechanisms of early atherosclerotic plaque growth and the risk of instability in the plaque growth.

Graphic abstract

中文翻译：

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血流动力学对动脉粥样硬化斑块发展和稳定性的影响

研究动脉粥样硬化斑块在血流动力学领域的形成和稳定性对于了解动脉粥样硬化斑块的生长机制和预防治疗至关重要。在本文中，基于多层多孔壁模型，我们建立了具有时变入口流的双向流固相互作用。描述了动脉粥样硬化斑块中的富脂坏死核心（LRNC）和应力，通过有限元法求解平流-扩散-反应方程来分析动脉粥样硬化斑块生长过程中的稳定性。研究发现，当斑块中凋亡物质（如巨噬细胞、泡沫细胞）的脂质水平达到指定的较低浓度时，LRNC出现，并随着斑块的生长而增加。LRNC与血压呈正相关，与血流速度呈负相关。最大应力主要位于坏死核心，并随着斑块的生长逐渐向斑块左肩移动，增加了斑块的不稳定性和斑块脱落的风险。该计算模型可能有助于理解早期动脉粥样硬化斑块生长的机制以及斑块生长不稳定的风险。

图文摘要