Department of Mechanical, Aerospace and Civil Engineering (MACE), The University of Manchester, Manchester, M13 9PL, UK.
Division of Cardiovascular Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Oxford Road, Manchester, M13 9PL, UK.
Ann Biomed Eng. 2021 Sep;49(9):2196-2213. doi: 10.1007/s10439-021-02744-9. Epub 2021 Mar 2.
Atrial fibrillation (AF) can alter intra-cardiac flow and cardiac output that subsequently affects aortic flow circulation. These changes may become more significant where they occur concomitantly with ageing. Aortic ageing is accompanied with morphological changes such as dilation, lengthening, and arch unfolding. While the recognition of AF mechanism has been the subject of numerous studies, less focus has been devoted to the aortic circulation during the AF and there is a lack of such investigation at different ages. The current work aims to address the present gap. First, we analyse aortic flow distribution in three configurations, which attribute to young, middle and old people, using geometries constructed via clinical data. We then introduce two transient inlet flow conditions representative of key AF-associated defects. Results demonstrate that both AF and ageing negatively affect flow circulation. The main consequence of concomitant occurrence is enhancement of endothelial cell activation potential (ECAP) throughout the vascular domain, mainly at aortic arch and descending thoracic aorta, which is consistent with some clinical observations. The outcome of the current study suggests that AF exacerbates the vascular defects occurred due to the ageing, which increases the possibility of cardiovascular diseases per se.
心房颤动（AF）可改变心内血流和心输出量，进而影响主动脉血流循环。这些变化在与衰老同时发生时可能更为显著。主动脉老化伴随着形态学变化，如扩张、延长和弓展开。虽然 AF 机制的认识已经成为许多研究的主题，但在 AF 期间对主动脉循环的关注较少，并且在不同年龄段缺乏此类研究。目前的工作旨在解决这一空白。首先，我们使用通过临床数据构建的几何形状，分析了归因于年轻人、中年人、老年人的三种配置下的主动脉血流分布。然后，我们引入了两种代表关键与 AF 相关缺陷的瞬态入口流条件。结果表明，AF 和衰老都会对血流循环产生负面影响。同时发生的主要后果是整个血管区域内皮细胞激活潜能（ECAP）增强，主要在主动脉弓和降胸主动脉，这与一些临床观察结果一致。本研究的结果表明，AF 加剧了因衰老而导致的血管缺陷，从而增加了心血管疾病本身的可能性。
