Supplementary Material for: Association between Rapid Ventricular Response and Stroke Outcomes in Atrial Fibrillation-Related Cardiac Embolic Stroke

<b><i>Introduction:</i></b> Patients with atrial fibrillation-related stroke (AF-stroke) are prone to developing rapid ventricular response (RVR). We investigated whether RVR is associated with initial stroke severity, early neurological deterioration (END) and poor outcome at 3 months. <b><i>Methods:</i></b> We reviewed patients who had AF-stroke between January 2017 and March 2022. RVR was defined as having heart rate &gt;100 beats per minute on initial electrocardiogram. Neurological deficit was evaluated with National Institutes of Health Stroke Scale (NIHSS) score at admission. END was defined as increase of ≥2 in total NIHSS score or ≥1 in motor NIHSS score within first 72 h. Functional outcome was score on modified Rankin Scale at 3 months. Mediation analysis was performed to examine potential causal chain in which initial stroke severity may mediate relationship between RVR and functional outcome. <b><i>Results:</i></b> We studied 568 AF-stroke patients, among whom 86 (15.1%) had RVR. Patients with RVR had higher initial NIHSS score (<i>p</i> &lt; 0.001) and poor outcome at 3 months (<i>p</i> = 0.004) than those without RVR. The presence of RVR [adjusted odds ratio (aOR) = 2.13; <i>p</i> = 0.013] was associated with initial stroke severity, but not with END and functional outcome. Otherwise, initial stroke severity [aOR = 1.27; <i>p</i> = &lt;0.001] was significantly associated with functional outcome. Initial stroke severity as a mediator explained 58% of relationship between RVR and poor outcome at 3 months. <b><i>Conclusion:</i></b> In patients with AF-stroke, RVR was independently associated with initial stroke severity but not with END and functional outcome. Initial stroke severity mediated considerable proportion of association between RVR and functional outcome.

**引言：** 心房颤动相关性卒中（atrial fibrillation-related stroke, AF-stroke）患者易出现快速心室反应（rapid ventricular response, RVR）。本研究旨在探讨快速心室反应是否与卒中初始严重程度、早期神经功能恶化（early neurological deterioration, END）及3个月不良预后相关。
**方法：** 回顾性分析2017年1月至2022年3月期间收治的心房颤动相关性卒中患者。快速心室反应定义为初始心电图提示心率＞100次/分。采用美国国立卫生研究院卒中量表（National Institutes of Health Stroke Scale, NIHSS）评分评估入院时的神经功能缺损情况。早期神经功能恶化定义为入院后72小时内总NIHSS评分升高≥2分或运动项NIHSS评分升高≥1分。采用改良Rankin量表评分评估患者3个月时的功能预后。本研究通过中介分析探讨初始卒中严重程度在快速心室反应与功能预后之间可能存在的因果关联路径。
**结果：** 本研究共纳入568例心房颤动相关性卒中患者，其中86例（15.1%）存在快速心室反应。与无快速心室反应的患者相比，合并快速心室反应的患者初始NIHSS评分更高（p＜0.001），且3个月不良预后发生率更高（p=0.004）。快速心室反应的存在[校正比值比（adjusted odds ratio, aOR）=2.13；p=0.013]与初始卒中严重程度显著相关，但与早期神经功能恶化及功能预后无显著关联。反之，初始卒中严重程度[aOR=1.27；p＜0.001]与功能预后显著相关。中介分析显示，初始卒中严重程度可解释快速心室反应与3个月不良预后之间58%的关联。
**结论：** 在心房颤动相关性卒中患者中，快速心室反应与初始卒中严重程度独立相关，但与早期神经功能恶化及功能预后无独立关联。初始卒中严重程度在快速心室反应与功能预后的关联中发挥了可观的中介作用。