Scarsoglio S, Saglietto A, Anselmino M, Gaita F, Ridolfi L
Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Torino, Italy
Division of Cardiology, Department of Medical Sciences, 'Città della Salute e della Scienza' Hospital, University of Turin, Torino, Italy.
J R Soc Interface. 2017 Apr;14(129). doi: 10.1098/rsif.2017.0180.
There has recently been growing evidence that atrial fibrillation (AF), the most common cardiac arrhythmia, is independently associated with the risk of dementia. This represents a very recent frontier with high social impact for the number of individuals involved and for the expected increase in AF incidence in the next 40 years. Although a number of potential haemodynamic processes, such as microembolisms, altered cerebral blood flow, hypoperfusion and microbleeds, arise as connecting links between the two pathologies, the causal mechanisms are far from clear. An approach is proposed that combines in sequence two lumped-parameter schemes, for the cardiovascular system and the cerebral circulation. The systemic arterial pressure is obtained from the cardiovascular system and used as the input for the cerebral circulation, with the aim of studying the role of AF on the cerebral haemodynamics with respect to normal sinus rhythm (NSR), over a 5000 beat recording. In particular, the alteration of the haemodynamic (pressure and flow rate) patterns in the microcirculation during AF is analysed by means of different statistical tools, from correlation coefficients to autocorrelation functions, crossing times, extreme values analysis and multivariate linear regression models. A remarkable signal alteration, such as a reduction in signal correlation (NSR, about 3 s; AF, less than 1 s) and increased probability (up to three to four times higher in AF than in NSR) of extreme value events, emerges for the peripheral brain circulation. The described scenario offers a number of plausible cause-effect mechanisms that might explain the occurrence of critical events and the haemodynamic links relating to AF and dementia.
最近，越来越多的证据表明，最常见的心律失常——心房颤动（AF）与痴呆风险独立相关。鉴于涉及的个体数量以及预计未来40年AF发病率的上升，这代表了一个具有重大社会影响的全新领域。尽管一些潜在的血液动力学过程，如微栓塞、脑血流改变、灌注不足和微出血，作为两种病理之间的联系而出现，但其因果机制仍远未明确。本文提出了一种方法，该方法依次结合了两种集总参数方案，分别用于心血管系统和脑循环。从心血管系统获取体循环动脉压，并将其用作脑循环的输入，目的是在5000次心跳记录期间研究AF相对于正常窦性心律（NSR）对脑血流动力学的作用。特别是，通过不同的统计工具，从相关系数到自相关函数、交叉时间、极值分析和多元线性回归模型，分析了AF期间微循环中血液动力学（压力和流速）模式的变化。对于外周脑循环，出现了显著的信号改变，如信号相关性降低（NSR约为3秒；AF小于1秒）以及极值事件的概率增加（AF比NSR高两到四倍）。所描述的情况提供了一些合理的因果机制，可能解释关键事件的发生以及与AF和痴呆相关的血液动力学联系。
