Silent stroke in patients with transient ischemic attack or minor ischemic stroke. The Dutch TIA Trial Study Group.

BACKGROUND AND PURPOSE: We studied silent stroke (i.e., infarcts on computed tomographic scan not related to later symptoms) in patients after transient ischemic attack or minor ischemic stroke. METHODS: Ours is a cross-sectional study of 2,329 patients who were randomized in a secondary prevention trial after transient ischemic attack or minor ischemic stroke and had no residual deficit after the qualifying event. RESULTS: Silent stroke was observed in 13% of the 2,329 patients. Lacunes formed 79%, cortical lesions 14%, and border zone lesions 7% of all silent strokes. Silent lacunes were most often located in the basal ganglia and symptomatic lacunes most often in the corona radiata. Age, hypertension, and current cigarette smoking were related to the presence of silent stroke. Silent stroke was equally common in different types of transient ischemic attack, including transient monocular blindness. Residual symptoms of any kind were more common in patients with silent stroke than in those without. CONCLUSIONS: Because only the sites of silent stroke infarcts differed slightly from those of symptomatic infarcts and the frequency of vascular risk factors was similar to that of symptomatic infarcts, silent stroke may have the same bearing on future risk as known prior stroke.     

Headache in transient or permanent cerebral ischemia. Dutch TIA Study Group

We studied headache features in 3,126 patients with acute cerebral or retinal ischemia. Headache occurred in 18% of these patients (in 16% of all patients with transient ischemic attacks, in 18% of patients with reversible ischemic neurologic deficits, and in 19% of patients with minor strokes) and was mostly continuous in all types of attacks. Headache was present in 16% of patients with monocular visual symptoms. The occurrence of headache was not related to the mode of onset, mode of disappearance, or duration of the attack. Patients with headache more often were known to have heart disease. Headache was less frequent in patients with small deep infarcts, who were more often hypertensive, and in patients with infarcts in the anterior circulation; headache was more frequent in patients with cortical infarcts and in patients with infarcts in the posterior circulation. Patients with a relevant small deep infarct on computed tomographic scan and accompanying headache relatively often reported symptoms compatible with cortical ischemia, such as language disorders or a visual field defect. We conclude that headache is a frequent accompanying symptom in patients with acute cerebral and retinal ischemia and that the occurrence of headache is partly related to the underlying cause of the ischemic lesion.     

Recurrent stroke after transient ischaemic attack or minor ischaemic stroke: does the distinction between small and large vessel disease remain true to type? Dutch TIA Trial Study Group.

The incidence and vascular type of recurrent ischaemic stroke was studied in patients with supratentorial transient ischaemic attacks or non-disabling ischaemic strokes, who were treated with aspirin (30 or 283 mg). Patients were divided into groups with small vessel disease (SVD) (n = 1216) or large vessel disease (LVD) (n = 1221) on the grounds of their clinical features and CT at baseline. Patients with evidence of both SVD and LVD (n = 180) were excluded from further analyses. During follow up (mean 2.6 years) annual stroke rate was 3.6% in both groups. Of the 107 patients with SVD at baseline who had recurrent strokes, 83 proved to have an identifiable infarct: 30 (28%) again had a small vessel infarct, 39 (36%) had a large vessel ischaemic stroke and in 14 (13%) the recurrent ischaemic stroke was in the posterior fossa. Of the 110 patients with LVD at baseline and recurrent stroke, 91 had an identifiable infarct: 67 (61%) again had a large vessel ischaemic stroke, 16 (15%) had a small vessel ischaemic stroke, and eight (7%) had the recurrent ischaemic stroke in the posterior fossa. Thus patients with a transient ischaemic attack or non-disabling ischaemic stroke caused by LVD were more likely to have an ischaemic stroke of the same vessel type during follow up than patients with SVD (relative risk 2.2; 95% confidence interval 1.5-3.4). Possible explanations for this difference are: (1) patients with a small vessel ischaemic stroke at baseline had both SVD and LVD or were misdiagnosed; (2) recurrent small vessel ischaemic stroke may have occurred more often than reported, because they were silent or only minimally disabling; (3) recurring large vessel ischaemic strokes occurring in patients initially diagnosed as having SVD might have been related to potential cardiac sources of emboli that had not been previously recognized; (4) the antiplatelet drug aspirin (30 or 283 mg) prescribed in this patient group may have prevented thrombosis in small vessels better than in large vessels.     

TIA,RIND, minor stroke: a continuum,or different subgroups? Dutch TIA Study Group.

The results of CT were studied prospectively in 606 patients with a transient ischaemic attack (TIA), 422 patients with a reversible ischaemic neurological deficit (RIND), and 1054 patients with a minor stroke, were all entered into a multi-centre clinical trial. CT scanning showed a relevant ischaemic lesion in 13% (95% confidence interval 10-16%) of TIAs, 35% (95% confidence interval 30-40%) of RINDs, and 49% (95% confidence interval 46-52%) of minor strokes (p less than 0.000001). Even within the 24 hour margin, relevant infarcts occurred more often with longer attacks, but were still found in some patients with attacks lasting less than a minute. The type and location of the infarcts were similar in the three groups. These findings suggest that the differences between TIAs, RINDs, and minor strokes are quantitative rather than qualitative.     

Intellectual function in patients with transient ischaemic attacks (TIA) or minor stroke

Psychological testing was performed in 25 patients (mean age 56 years) with transient ischaemic attacks and/or minor strokes and with angiographically verified internal carotid artery stenosis. The effects of carotid endarterectomy on intellectual functions were evaluated postoperatively at 2 weeks and 8 months respectively. Preoperatively the mean test values were below the normal level for all tests indicating a general intellectual impairment for the group as a whole. This may reflect multiinfarct dementia in statu nascendi . At the early postoperative test session some test results were statistically significantly worse than the preoperative. 8 months postoperatively the mean values for all tests had improved as compared with the preoperative values. This improvement reached a statistically significant level in 6 tests. When the side of operation was considered a pattern emerged: in the 12 patients with left-sided endarterectomies improvement was significant for tests mainly related to left-hemisphere function (Word Pairs Test, Story Recall, Trail Making B, Similarities) and in the 13 patients with right-sided endarterectomies significant improvement occurred in the functions mainly related to the right hemisphere (Visual Gestalts, Block Design, Digit Span backwards). This relationship between side of operation and improvement in lateralized functions cannot be explained by retest effects.
It is concluded that TIA's and minor strokes per se may impair intellectual function, and that reversal of deterioration and even improved mental state may follow carotid endarterectomy.     

脑梗死患者脑白质病变及其危险因素

目的 探讨脑梗死患者脑白质病变(white matter lesions,WML)患病情况及其危险因素.方法 采用多中心横断面研究和病例-病例对照研究.收集全国12家医院2004年5月至12月连续就诊的1～6个月内脑梗死患者720例的临床资料.分别对头MRI显示的脑梗死部位、大小、血管分布、血管类型做出判断,用年龄相关性白质改变评分法(Age-Related White Matter Changes Scales,ARWMC)测量脑白质病变,阅片者不了解患者的临床资料.采用Logistic回归检验独立危险因素.结果 MRI图像质量完好700例[平均年龄(59.93±9.86)岁,男/女为481/219],WML患病率77.4%,随年龄增长患病率和病变严重程度增加.额叶病变最多,程度最重.Logistic回归显示高龄(OR 1.09,95% CI 1.067～1.114)、舒张压升高(OR 1.039,95% CI 1.018～1.06)、基底节梗死(OR2.244,95% CI 1.609～3.708)与WML存在独立相关.结论 脑梗死患者WML普遍存在.病变以额叶最明显.高龄、舒张压升高、基底节梗死是发生WML的独立危险因素.