Clinical Neuroscience, St. George's University of London, Cranmer Terrace, London, SW17 0RE, UK.
Stroke. 2009 Dec;40(12):3711-7. doi: 10.1161/STROKEAHA.109.563056. Epub 2009 Oct 22.
Asymptomatic embolic signals (ES) detected using transcranial Doppler have been reported in patients with potential cerebral embolic sources. They may be useful in risk stratification and in assessing therapies. First, it is essential to show whether they predict stroke risk.
A systematic review and meta-analysis was performed to determine the prognostic value of ES in different potential cerebral embolic sources. Studies were identified that used transcranial Doppler to detect ES and included prospective stroke/TIA follow-up. Numbers of ES-positive and ES-negative patients were extracted with stroke/TIA and stroke alone outcomes.
ES are most frequent in large artery disease, less frequent in cardioembolic stroke, and infrequent in lacunar stroke. Data relating ES to future stroke risk were available for acute stroke, large artery disease, and the perioperative period of carotid endarterectomy. For symptomatic carotid stenosis, ES predicted stroke alone (OR, 9.57; 95%CI, 1.54 to 59.38; P=0.02) and stroke/TIA (OR, 6.36; 95% CI, 2.90-13.96; P<0.00001). For asymptomatic carotid stenosis, ES predicted stroke alone (OR, 7.46; 95% CI, 2.24-24.89; P=0.001) and stroke/TIA (OR, 12.00; 95% CI, 2.43-59.34; P=0.002) but with heterogeneity (P=0.004). In acute stroke ES predicted stroke alone (OR, 2.44; 95% CI, 1.17-5.08; P=0.02) and stroke/TIA (OR, 3.71; 95% CI, 1.64-8.38; P=0.002). A high frequency of ES immediately after carotid endarterectomy predicted stroke alone (OR, 24.54; 95% CI, 7.88-76.43; P<0.00001) and stroke/TIA (OR, 32.04; 95% CI, 11.36-90.39; P<0.00001).
ES predict stroke risk in acute stroke, symptomatic carotid stenosis, and postoperatively after carotid endarterectomy; in asymptomatic carotid stenosis, data are less robust. In these conditions ES may be useful in risk stratification and in assessing therapeutic efficacy. For other embolic sources, further prospective data are required.
经颅多普勒检测到的无症状栓塞信号（ES）已在潜在脑栓塞源患者中报告。它们可能在风险分层和评估治疗中有用。首先，必须证明它们是否可以预测中风风险。
进行了系统评价和荟萃分析，以确定不同潜在脑栓塞源中 ES 的预后价值。确定了使用经颅多普勒检测 ES 并包括前瞻性中风/TIA 随访的研究。提取 ES 阳性和 ES 阴性患者的中风/TIA 和中风单独的结果。
ES 在大动脉疾病中最常见，在心源性中风中较少见，在腔隙性中风中罕见。与未来中风风险相关的数据可用于急性中风、大动脉疾病和颈动脉内膜切除术的围手术期。对于有症状的颈动脉狭窄，ES 预测中风单独发生（OR，9.57；95%CI，1.54-59.38；P=0.02）和中风/TIA（OR，6.36；95%CI，2.90-13.96；P<0.00001）。对于无症状性颈动脉狭窄，ES 预测中风单独发生（OR，7.46；95%CI，2.24-24.89；P=0.001）和中风/TIA（OR，12.00；95%CI，2.43-59.34；P=0.002），但存在异质性（P=0.004）。在急性中风中，ES 预测中风单独发生（OR，2.44；95%CI，1.17-5.08；P=0.02）和中风/TIA（OR，3.71；95%CI，1.64-8.38；P=0.002）。颈动脉内膜切除术后立即出现大量 ES 预测中风单独发生（OR，24.54；95%CI，7.88-76.43；P<0.00001）和中风/TIA（OR，32.04；95%CI，11.36-90.39；P<0.00001）。
ES 预测急性中风、有症状性颈动脉狭窄和颈动脉内膜切除术后的中风风险；在无症状性颈动脉狭窄中，数据的可靠性较低。在这些情况下，ES 可能在风险分层和评估治疗效果方面有用。对于其他栓塞源，需要进一步的前瞻性数据。
