Gao Shan, Wong Ka Sing, Hansberg Tjark, Lam Wynnie W M, Droste Dirk W, Ringelstein E Bernd
Department of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong SAR.
Stroke. 2004 Dec;35(12):2832-6. doi: 10.1161/01.STR.0000147035.31297.b6. Epub 2004 Oct 28.
Cerebral embolism is a common cause of stroke. Microembolic signals (MES) detected by transcranial Doppler represent ongoing embolisms, but the lack of reliable data about its clinical relevance hinders its widespread use in clinical practice.
We prospectively monitored 114 consecutive acute ischemic stroke patients with middle cerebral artery (MCA) stenosis for MES. The signals on digital audio tape were analyzed by an independent observer who was blinded to all other data. All patients were followed-up for the occurrence of recurrent stroke or transient ischemic attack (TIA) in the indexed MCA territory.
MES was detected in 25 (22%) patients. The mean number of MES was 18 (range, 1 to 102). MES were more common in patients with severe stenosis (10/21, 48%) than in those with mild-moderate stenosis (4/26, 15%) (Pearson chi2 P=0.02). During follow-up for a mean of 13.6 months (range, 1 to 32), 12 (12%) patients had further ischemic events (10 strokes and 2 TIAs) in the affected MCA region during follow-up. Among these, 7 (58%) had recurred within 1 month (1 recurred within 1 week, the other 6 patients had recurrences in week 3 or 4 after discharge), 3 within 6 months, 1 within 6 to 12 months, and the remaining 1 recurred after 1 year. The presence of MES was the only predictor of a further ischemic stroke/TIA by Cox regression (adjusted odds ratio, 8.45; 95% CI, 1.69 to 42.22; P=0.01) even after controlling for age, sex, diabetes, hypertension, previous stroke, smoking, and acute treatment.
In acute stroke patients with MCA stenosis, MES predicts further cerebral ischemia. This procedure should be considered as part of routine investigation and might identify a group of patients who are most likely to benefit from antithrombotic treatment.
脑栓塞是卒中的常见病因。经颅多普勒检测到的微栓子信号（MES）代表正在发生的栓塞，但缺乏关于其临床相关性的可靠数据阻碍了其在临床实践中的广泛应用。
我们前瞻性地监测了114例连续的大脑中动脉（MCA）狭窄的急性缺血性卒中患者的MES。数字录音带上的信号由一名对所有其他数据均不知情的独立观察者进行分析。所有患者均随访索引MCA区域复发性卒中或短暂性脑缺血发作（TIA）的发生情况。
25例（22%）患者检测到MES。MES的平均数量为18个（范围1至102个）。严重狭窄患者中MES更常见（10/21，48%），而轻度至中度狭窄患者中为4/26（15%）（Pearson卡方检验P=0.02）。在平均13.6个月（范围1至32个月）的随访期间，12例（12%）患者在随访期间受影响的MCA区域发生了进一步的缺血事件（10次卒中，2次TIA）。其中，7例（58%）在1个月内复发（1例在1周内复发，其他6例患者在出院后第3或4周复发），3例在6个月内复发，1例在6至12个月内复发，其余1例在1年后复发。即使在控制了年龄、性别、糖尿病、高血压、既往卒中、吸烟和急性治疗因素后，MES的存在仍是Cox回归分析中进一步缺血性卒中/TIA的唯一预测因素（校正比值比，8.45；95%可信区间，1.69至42.22；P=0.01）。
在MCA狭窄的急性卒中患者中，MES可预测进一步的脑缺血。该检查应被视为常规检查的一部分，可能识别出最有可能从抗栓治疗中获益的一组患者。
