Department of Neurology, Adelaide and Meath Hospital, Dublin, incorporating the National Children's Hospital (AMNCH)/Tallaght University Hospital, Dublin, Ireland.
Stroke Service, Adelaide and Meath Hospital, Dublin, incorporating the National Children's Hospital (AMNCH)/Tallaght University Hospital, Dublin, Ireland.
Thromb Haemost. 2019 May;119(5):821-833. doi: 10.1055/s-0039-1678666. Epub 2019 Feb 15.
Cerebral micro-embolic signals (MES) predict risk of stroke in carotid stenosis patients. However, MES-negative 'recently symptomatic patients' also have a higher stroke risk than 'asymptomatic patients'. Differences in platelet activation status may contribute to this disparity in risk.
This prospective, observational study assessed platelet biomarkers and their relationship with MES in asymptomatic versus symptomatic moderate (≥50-69%) or severe (≥70-99%) carotid stenosis patients. Full blood count parameters were measured and whole-blood flow cytometry was used to quantify platelet surface CD62P and CD63 expression and leucocyte-platelet complex formation. Bilateral simultaneous transcranial Doppler ultrasound of the middle cerebral arteries classified patients as 'MES positive' or 'MES negative'.
Data from 34 asymptomatic patients were compared with those from 43 symptomatic patients in the 'early phase' (≤ 4 weeks) and 37 of these symptomatic patients in the 'late phase' (≥ 3 months) after transient ischaemic attack/ischaemic stroke. There were no differences in %CD62P or %CD63 expression between early or late symptomatic and asymptomatic patients overall ( > 0.05). The percentage of lymphocyte-platelet complexes was higher in early symptomatic than in asymptomatic patients (2.8 vs. 2.16%; < 0.001). MES were more commonly observed in early symptomatic (31.4%; = 0.027) but not in late symptomatic (6.7%; = 0.996) versus asymptomatic patients (7.1%). The percentage of lymphocyte-platelet complexes was higher in early symptomatic than in asymptomatic MES-negative patients (2.7 vs. 2.17%; = 0.02).
These data add to the evidence that leucocyte-platelet complex formation/platelet activation is increased in recently symptomatic versus asymptomatic patients, and may contribute to the pathogenesis of first and subsequent strokes in carotid stenosis patients, including those who are MES negative.
脑微栓子信号（MES）可预测颈动脉狭窄患者发生中风的风险。然而，MES 阴性的“近期症状性患者”的中风风险也高于“无症状患者”。血小板激活状态的差异可能导致这种风险差异。
这项前瞻性、观察性研究评估了无症状与症状性中度（≥50-69%）或重度（≥70-99%）颈动脉狭窄患者之间血小板生物标志物及其与 MES 的关系。测量全血细胞参数，并使用全血流式细胞术定量血小板表面 CD62P 和 CD63 表达以及白细胞-血小板复合物形成。双侧同时经颅多普勒超声检查大脑中动脉将患者分类为“MES 阳性”或“MES 阴性”。
将 34 名无症状患者的数据与 43 名早期（≤4 周）和这些症状性患者中的 37 名晚期（≥3 个月）短暂性脑缺血发作/缺血性中风后症状性患者的数据进行了比较。在总体上，早期或晚期症状性与无症状患者之间的%CD62P 或%CD63 表达无差异（>0.05）。与无症状患者相比，早期症状性患者中淋巴细胞-血小板复合物的百分比更高（2.8%比 2.16%；<0.001）。MES 在早期症状性患者中更为常见（31.4%；=0.027），而在晚期症状性患者中则不常见（6.7%；=0.996）（无症状患者为 7.1%）。与无症状 MES 阴性患者相比，早期症状性患者中淋巴细胞-血小板复合物的百分比更高（2.7%比 2.17%；=0.02）。
这些数据进一步证明，与无症状患者相比，新近出现症状的患者中白细胞-血小板复合物形成/血小板激活增加，这可能导致颈动脉狭窄患者首次和随后发生中风的发病机制，包括那些 MES 阴性的患者。
