随着时间的推移,AVF中的血液动力学:血管改造对稳定流量的保护作用
Luca Soliveri1, Michela Bozzetto1, Paolo Brambilla2,3
1Department of Biomedical Engineering, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy.
The International journal of artificial organs
|September 27, 2023
概括
动脉静脉 (AVF) 中血流不稳定可能引发内脏增生和狭窄. 血管改造旨在调节这种流动,可能导致血液透析患者的AVF衰竭.
科学领域:
- 生物医学工程 生物医学工程
- 心血管研究研究心血管研究
- 医疗成像医学成像
背景情况:
- 动脉静脉 (AVF) 狭窄是导致血液透析无法进入的常见原因.
- AVF狭窄的潜在机制,特别是内脏增生,尚未完全理解.
- 以前的计算流体动力学 (CFD) 研究表明,不稳定的流量有助于狭窄,但往往缺乏纵向数据.
研究的目的:
- 研究AVF中血液动力学条件和血管重塑之间的纵向关系.
- 用CFD模拟来分析AVF形态和血液流量的变化.
- 探索流动模式在AVF狭窄的发展中的作用.
主要方法:
- 长度CFD研究利用MRI和多普勒超声波的患者特定数据.
- 在多个时间点获取成像数据:手术后3天,40天,6个月,1年和1.5年.
- 使用患者特定边界条件的pimpleFoam进行的高准确度CFD模拟.
主要成果:
- 在6个月内,AVF表现出成功的成熟,具有显著的扩张和增加的血流.
- 在成熟阶段观察到流动不稳定性.
- 在6个月至1年之间,在近静脉静脉中形成了狭窄,导致1.5年后的AVF衰竭.
- 狭窄的发展与流量规范化相关,并减少近壁扰乱流量指标.
结论:
- 不稳定的流动和相关的血液动力学障碍可能会引发内脏增生和AVF狭窄.
- 血管重塑似乎是对规范流式流动的反应.
- 这些发现提供了对AVF失效机制和潜在治疗点的见解.
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