Background

Circadian variability has been implicated in timing of stroke onset, yet the full impact of underlying biological rhythms on acute stroke perfusion patterns is not known. We aimed to describe the relationship between time of stroke onset and perfusion profiles in patients with large vessel occlusion (LVO).

Methods

A retrospective observational study was conducted using prospective registries of four stroke centers across North America and Europe with systematic use of perfusion imaging in clinical care. Included patients had stroke due to ICA, M1 or M2 occlusion and baseline perfusion imaging performed within 24h from last-seen-well (LSW). Stroke onset was divided into eight hour intervals: (1) Night: 23:00-6:59, (2) Day: 7:00-14:59, (3) Evening: 15:00-22:59. Core volume was estimated on CT perfusion (rCBF <30%) or DWI-MRI (ADC <620) and the collateral circulation was estimated with the Hypoperfusion Intensity Ratio (HIR = [Tmax>10s]/[Tmax>6s]). Non-parametric testing was conducted using SPSS to account for the non-normalized dependent variables.

Results

A total of 1506 cases were included (median age 74.9 years, IQR 63.0-84.0). Median NIHSS, core volumes, and HIR were 14.0 (IQR 8.0-20.0), 13.0mL (IQR 0.0-42.0), and 0.4 (IQR 0.2-0.6) respectively. Most strokes occurred during the Day (n = 666, 44.2%), compared to Night (n = 360, 23.9%), and Evening (n = 480, 31.9%). HIR was highest, indicating worse collaterals, in the Evening compared to the other timepoints (p = 0.006). Controlling for age and time to imaging, Evening strokes had significantly higher HIR compared to Day (p = 0.013).

Conclusion

Our retrospective analysis suggests that HIR is significantly higher in the evening, indicating poorer collateral activation which may lead to larger core volumes in these patients.

中文翻译：

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在夜间出现的大血管闭塞 (LVO) 患者中观察到低灌注强度比 (HIR) 升高

背景

昼夜节律变异与中风发作的时间有关，但潜在生物节律对急性中风灌注模式的全面影响尚不清楚。我们旨在描述大血管闭塞 (LVO) 患者中风发作时间与灌注曲线之间的关系。

方法

使用北美和欧洲四个卒中中心的前瞻性登记系统进行了一项回顾性观察研究，并在临床护理中系统地使用了灌注成像。包括的患者因 ICA、M1 或 M2 闭塞而发生中风，并且基线灌注成像在最后一孔 (LSW) 的 24 小时内进行。中风发作分为八小时间隔：(1) 夜间：23:00-6:59，(2) 白天：7:00-14:59，(3) 晚上：15:00-22:59。根据 CT 灌注 (rCBF <30%) 或 DWI-MRI (ADC <620) 估算核心体积，并根据低灌注强度比 (HIR = [Tmax>10s]/[Tmax>6s]) 估算侧支循环。使用 SPSS 进行非参数测试以说明非标准化因变量。

结果

共纳入 1506 例（中位年龄 74.9 岁，IQR 63.0-84.0）。中位 NIHSS、核心体积和 HIR 分别为 14.0 (IQR 8.0-20.0)、13.0mL (IQR 0.0-42.0) 和 0.4 (IQR 0.2-0.6)。大多数中风发生在白天 (n = 666, 44.2%)，而夜间 (n = 360, 23.9%) 和晚上 (n = 480, 31.9%)。与其他时间点相比，晚上的 HIR 最高，表明侧支循环较差 (p = 0.006)。控制年龄和成像时间后，夜间卒中的 HIR 明显高于白天 (p = 0.013)。

结论

我们的回顾性分析表明，HIR 在晚上明显更高，表明侧支激活较差，这可能导致这些患者的核心体积更大。