Search

Background and Purpose: We assessed the outcomes of dabigatran versus aspirin in a prespecified subgroup analysis of East Asian patients with embolic stroke of undetermined source in the RE-SPECT ESUS trial (Randomized, Double-Blind, Evaluation in Secondary Stroke Prevention Comparing the Efficacy and Safety of the Oral Thrombin Inhibitor Dabigatran Etexilate Versus Acetylsalicylic Acid in Patients With Embolic Stroke of Undetermined Source). Methods: Patients with a recent embolic stroke of undetermined source were randomized to dabigatran (150 or 110 mg BID) or aspirin (100 mg QD). The primary efficacy outcome was recurrent stroke; the primary safety outcome was major bleeding. The East Asia cohort was compared with patients from all other countries (non-East Asia cohort). Results: Overall, 988 of 5390 patients (18%) were randomized in East Asia. During a median follow-up of 18.8 months, there was no statistically significant difference in recurrent stroke (hazard ratio, 0.65 [95% CI, 0.41–1.03]) or major bleeding (hazard ratio, 1.04 [95% CI, 0.57–1.91]) in East Asian patients receiving dabigatran versus aspirin. Death from any cause occurred more often in the dabigatran versus the aspirin group (hazard ratio, 3.98 [95% CI, 1.32–12.01]). Conclusions: The treatment effect of dabigatran versus aspirin was consistent between cohorts, with no apparent superiority for dabigatran over aspirin in preventing recurrent stroke in patients with embolic stroke of undetermined source. Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT02239120.

Background and Purpose— Posterior circulation ischemic stroke (IS) is generally considered an illness with a poor prognosis. However, there are no effective rating scales to predict recurrent stroke following it. Therefore, our aim was to identify clinical or radiological measures that could assist in predicting recurrent cerebral ischemic episodes. Methods— We prospectively enrolled 723 noncardiogenic posterior circulation IS patients with onset of symptoms Results— A total of 40 patients (5.5%) had recurrent IS or TIA within 1 year of posterior circulation IS. Multivariate Cox regression identified chief complaint with dysphagia (hazard ratio [HR], 4.16; 95% confidence interval [CI], 1.69–10.2; P =0.002), repeated TIAs within 3 months before the stroke (HR, 15.4; 95% CI, 5.55–42.5; P P =0.05), multisector infarcts (HR, 5.38; 95% CI, 1.25–23.3; P =0.02), and not on antithrombotics treatment at discharge (HR, 3.06; 95% CI, 1.09–8.58; P =0.03) as independent predictors of recurrent IS or TIA. Conclusions— Some posterior circulation IS patients are at higher risk for recurrent IS or TIA. Urgent assessment and preventive treatment should be offered to these patients as soon as possible.

Background and Purpose— Poststroke autonomic dysfunction portended an unfavorable prognosis. We investigated whether blood pressure variability (BPV), heart rate variability, and baroreflex sensitivity might predict stroke functional outcome. Methods— We calculated BPV, heart rate variability, baroreflex slope, and baroreflex effectiveness index from a 5-minute beat-to-beat blood pressure and heart rate monitoring within 7 days from the stroke onset. We compared the parameters between patients with a good outcome (modified Rankin Scale score, 0–2) and those with a poor outcome. Results— Among 142 patients (mean age, 63.9±10.2 years; 88.0% men), functional outcome was good in 112 (78.9%) and poor in 30 (21.1%). There were significant differences in admission National Institutes of Health Stroke Scale, prior stroke, high-frequency systolic BPV, low/high-frequency ratio of BPV, baroreflex sensitivity-up, and baroreflex sensitivity-total between the 2 groups (all P P P =0.041), and baroreflex effectiveness index-down (OR, 0.958 [95% CI, 0.924–0.992]; P =0.017) independently predicted a poor functional outcome. Conclusions— A decreased low/high-frequency ratio of systolic BPV and impaired baroreflex sensitivity predicted an unfavorable stroke outcome, in addition to the established prognostic factor such as the National Institutes of Health Stroke Scale.

Background and Purpose— High signal on T1-weighted fat-suppressed images in middle cerebral artery plaques on ex vivo magnetic resonance imaging was verified to be intraplaque hemorrhage histologically. However, the underlying plaque component of low signal on T1-weighted fat-suppressed images (LST1) has never been explored. Based on our experience, we hypothesized that LST1 might indicate the presence of lipid core within intracranial plaques. Methods— 1.5 T magnetic resonance imaging was performed in the postmortem brains to scan the cross sections of bilateral middle cerebral arteries. Then middle cerebral artery specimens were removed for histology processing. LST1 presence was identified on magnetic resonance images, and lipid core areas were measured on the corresponding histology sections. Results— Total 76 middle cerebral artery locations were included for analysis. LST1 showed a high specificity (96.9%; 95% confidence interval, 82.0%–99.8%) but a low sensitivity (38.6%; 95% confidence interval, 24.7%–54.5%) for detecting lipid core of all areas. However, the sensitivity increased markedly (81.2%; 95% confidence interval, 53.7%–95.0%) when only lipid cores of area ≥0.80 mm 2 were included. Mean lipid core area was 5× larger in those with presence of LST1 than in those without (1.63±1.18 mm 2 versus 0.32±0.31 mm 2 ; P =0.003). Conclusions— LST1 is a promising imaging biomarker of identifying intraplaque lipid core, which may be useful to distinguish intracranial atherosclerotic disease from other intracranial vasculopathies and to assess plaque vulnerability for risk stratification of patients with intracranial atherosclerotic disease. In vivo clinical studies are required to explore the correlation between LST1 and clinical outcomes of patients with intracranial atherosclerotic disease.

Background and Objectives: External counterpulsation (ECP) is a non-invasive method used to augment cerebral blood flow of patients with ischaemic stroke via induced hypertension. We aimed to investigate whether the cerebral augmentation index (CAI) evaluated by ECP can predict clinical outcomes after acute ischemic stroke. Methods: We enrolled acute ischemic stroke patients within 7 days after stroke onset. Bilateral middle cerebral arteries of patients were monitored using transcranial Doppler (TCD). Flow velocity changes before, during and after ECP were, respectively, recorded for 3 mins. The cerebral augmentation index (CAI) was the increase in percentage of the middle cerebral artery mean flow velocity during ECP compared with baseline. TCD data were analysed based on the side ipsilateral or contralateral to the infarct. The modified Rankin Scale (mRS) (good outcome: mRS 0∼2; poor outcome: mRS 3∼6) was evaluated 3 months after the index stroke. Results: 200 patients were included (mean age, 64.5±8.9 years; 86.5% males). At month 3 after stroke onset, univariate analysis showed that the National Institutes of Health Stroke Scale at recruitment was significantly higher in the poor outcome group, while the bilateral CAIs were significantly lower in the good outcome group than those in the poor outcome group (ipsilateral 3.72±2.94 vs 7.92±6.25, p=0.032; contralateral 4.04±3.82 vs 6.98±6.05, p=0.048). Multivariate logistic regression showed that bilateral CAIs were independently correlated with an unfavorable functional outcome after adjusting for confounding factors. Conclusions: The higher degree of cerebral blood flow velocity augmentation on the both sides ipsilateral and contralateral to the infarct induced by ECP is independently correlated with an unfavorable functional outcome after acute ischemic stroke.

Background and Purpose— Intracranial artery calcification detected by computed tomography is associated with ischemic stroke as an indicator of intracranial atherosclerosis. However, little is known about its histopathology. This study aimed to explore the intracranial calcification patterns and their associations with atherosclerotic plaques. Methods— We recruited 32 adult autopsy cases to assess the calcification patterns and distributions in the middle cerebral artery, vertebral artery, and basilar artery. The relationships of calcification patterns with plaque phenotype and luminal stenosis were evaluated. The calcification patterns on computed tomography were correlated with that on histology. Results— Visible calcifications were detected within 37 (39%) segments, including 25 segments with intimal calcification, 6 segments with internal elastic lamina calcification, 3 segments with adventitial calcification, and 3 segments with concurrent calcification. Calcification occurred more often in the vertebral artery (51%), followed by the middle cerebral artery (35%) and basilar artery (14%; P P P Conclusions— Our histological findings indicate that the presence of intracranial artery calcification has 3 patterns, including intimal, internal elastic lamina, and adventitial calcifications. But only intimal calcification is related with progressive atherosclerotic lesions, indicative of a proxy for intracranial atherosclerosis.

Background and Purpose— Clinical trial studies show that plaque eccentricity (symmetry) is among the plaque features that have been associated with more frequent cerebrovascular events. Plaque eccentricity of intracranial atherosclerotic disease is unclear because of lacking of cerebral artery specimens. Methods— 1.5T magnetic resonance imaging was performed in the postmortem brains to scan the cross sections of middle cerebral artery. Plaque eccentricity of histology-verified middle cerebral artery atherosclerosis was calculated on T1-weighted fat-suppressed sequence. Results— Validated by histology, concentric atherosclerotic plaques were identified in 46 middle cerebral arteries (63.9%) on magnetic resonance imaging and eccentric plaques in 26 arteries (26.1%). Eccentric plaques showed higher maximum wall thickness and lower minimum wall thickness than concentric plaques (both P Conclusions— Intracranial atherosclerosis presents as eccentric or concentric in geometry, which may be not linked to intracranial plaque risk. Further in vivo imaging studies are needed to identify morphological features of intracranial plaques and to verify its association with brain infarctions.

Background and Purpose: Vasa vasorum, which constitutes a network of microvasculature, plays a nutritive and drainable role in vessel walls of arteries. The existence of vasa vasorum within brain vasculature is rarely reported. Based on a series of cerebral artery specimens, we aimed to describe the distribution features of vasa vasorum among intracranial arteries, including middle cerebral arteries (MCAs), basilar arteries (BAs) and vertebral arteries (VAs) and potential effects of vasa vasorum on atherosclerosis morphology. Methods: One hundred and fifty- seven arteries (64 MCAs, 32 Bas and 61 VAs) were obtained from consecutively recruited 32 autopsy cases aged 45 years or above. Routine histology and immunostaining processing were performed to identify the presence of adventitial vasa vasorum and to study the phenotypes and specific components of intracranial atherosclerotic lesions. Results: Among 157 intracranial cerebral arteries, adventitial vasa vasorum were present most frequently in the vertebral arteries (77%), followed by basilar arteries (44%) and middle cerebral arteries (20%). Arteries with adventitial vasa vasorum had greater thickness of tunica adventitia (0.10±0.06 mm vs. 0.06±0.03 mm, p &lt 0.001) and larger size in diameters (3.41± 0.73 mm vs. 2.97± 0.66 mm, p &lt 0.001). The occurrence of adventitial vasa vasorum correlated with high frequency of complicated plaques and higher rate of concentric atherosclerotic lesions (70% vs. 36%, p &lt 0.001). Conclusion: For the first time, our study demonstrated the presence of adventitial vasa vasorum within brain vasculature, especially at vertebral arteries. The correlations between adventitial vasa vasorum and intraplaque hemorrhage, inflammation and calcification suggest that adventitial vasa vasorum may serve as a predictor of unstable atherosclerotic lesions. Further studies are required to explore the biological behavior of adventitial vasa vasorum within cerebral arteries.

Introduction: Intracranial arterial calcification (IAC) is frequently observed on brain computed tomography (CT) in stroke patients. However, the association between IAC and stroke recurrence after hospital discharge has received little attention. In this study, we aim to explore the effect of IAC on the long-term stroke recurrence. Subjects and methods: We prospectively recruited consecutive patients with ischemic stroke or transient ischemic attack during December 2004 and March 2005 from a population-based stroke registry at Prince of Wales Hospital. Demographic characteristics, stroke risk factors, and stroke etiology were recorded at baseline. IAC volume and IAC Agatston score were both measured on 16-slice CT with a semi-automatic system. All patients were regularly followed up for stroke recurrence till July 2016. Results: Total 694 patients (age 71.6±12.4; male sex 50.3%; median follow-up period 8.8 years) were followed up. Stroke recurred in 156 patients (22.5%). Multivariate Cox proportional hazard model found higher IAC Agatston score was predictive factor for both recurrent stroke (HR per 1-SD increment 1.301; 95% CI, 1.084-1.561, p =0.005) and stroke death (HR per 1-SD increment, 1.441; 95% CI, 1.061-1.956, p =0.019). In addition, among different stroke etiological subtypes, IAC Agatston score was independent risk factor of stroke recurrence for index small-vessel occlusive stroke patients (HR per 1-SD increment, 1.674; 95% CI, 1.061-2.639, p =0.027). Conclusions: Quantitative-evaluated IAC scores can predict long-term stroke recurrence and stroke death.

Background and Purpose— Central autonomic dysfunction increases stroke morbidity and mortality. We aimed to investigate whether poststroke autonomic dysfunction graded by Ewing battery can predict clinical outcome. Methods— In this prospective observational study, we assessed autonomic function of ischemic stroke patients within 7 days from symptom onset by Ewing battery. On the basis of the magnitude of autonomic dysfunction, we stratified patients into significant (definite, severe, or atypical) or minor (normal or early) autonomic function impairment groups and correlated the impairment with the 3-month modified Rankin Scale score (good outcome: modified Rankin Scale score 0≈2; poor outcome: modified Rankin Scale score 3≈6). Results— Among the 150 patients enrolled (mean age, 66.4±9.9 years; 70.7% males), minor autonomic dysfunction was identified in 36 patients (24.0%), and significant autonomic dysfunction was identified in 114 patients (76.0%) based on Ewing battery. In 3 months, a poor functional outcome was found in 32.5% of significant group patients compared with 13.9% in the minor group ( P =0.031). Crude odds ratios of the magnitude of autonomic dysfunction and 3-month unfavorable functional outcome after acute ischemic stroke were 2.979 (95% confidence interval, 1.071–8.284; P =0.036). After adjusting for confounding variables with statistical significance between the 2 functional outcome subgroups identified in univariate analysis (including sex and National Institutes of Health Stroke Scale score on admission), the magnitude of autonomic dysfunction still independently predicted an unfavorable outcome, with an odds ratio of 3.263 (95% confidence interval, 1.141–9.335; P =0.027). Conclusions— Autonomic dysfunction gauged by Ewing battery predicts poor functional outcome after acute ischemic stroke.

Background and Purpose— Cerebral microbleeds (CMBs) are common in stroke survivors and community-dwelling elderly. The clinical significance of CMBs in the outcome of poststroke depression (PSD) is unknown. This study examined the association between the 1-year outcome of PSD and CMBs. Methods— The study population comprised 774 Chinese patients with acute ischemic stroke who were admitted to the acute stroke unit of a university-affiliated regional hospital in Hong Kong. Three and 15 months after the onset of the index stroke, a research assistant administered the locally validated 15-item Geriatric Depression Scale. PSD was defined as a Geriatric Depression Scale score of ≥7. Of the 213 patients with PSD at the 3-month follow-up, 135 (63.4%) attended the 15-month follow-up, at which time 89 (65.9%) patients remained depressed (nonremitters), and 46 (34.1%) had recovered (remitters). The presence and location of CMBs were evaluated with magnetic resonance imaging. Results— In comparison with the remitters, nonremitters were more likely to have lobar CMBs (18.4% versus 4.3%; P =0.024). Lobar CMBs remained an independent predictor of PSD in the multivariate analysis, with an odds ratio of 4.96 ( P =0.039). Conclusions— The results suggest that lobar CMBs may influence the outcome of PSD. The importance of CMBs in the clinical course of depression in stroke survivors warrants further investigation.

Background and Purpose— Geographic variation and sex difference in the distribution of intracranial atherosclerosis (ICAS) have not been fully discussed before in Chinese patients with cerebral ischemia. We performed this study with the aim to investigate geographic and sex difference in the distribution of ICAS in China. Methods— In this prospective multicenter study, we evaluated 2864 consecutive patients who experienced an acute cerebral ischemia within 7 days of symptom onset in 22 hospitals in China. All the inclusive patients underwent 3-dimensional time-of-flight MR angiography and duplex color Doppler ultrasound or contrast-enhanced MR angiography to document the presence of intracranial or extracranial stenosis. Intracranial large-artery atherosclerosis was defined as ≥50% diameter reduction on MR angiography. Results— The proportion of patients with ICAS was significantly higher in north China than in south China (50.22% versus 41.88%; P 63 years, the percentage of ICAS in women was notably higher than in men (51.51% versus 45.40%; P =0.028). In elderly patients, women had higher proportion of diabetes mellitus, hypertension, hyperlipidemia, and heart disease than men. Conclusions— There exists geographic and sex difference in the distribution of symptomatic ICAS in China. Public health measures should strengthen improving social determinants of health and risk factor prevention/control in high-risk populations for decreasing stroke risk.

Background and Purpose— Large artery intracranial occlusive disease (LAICOD) is a predominant cause of ischemic stroke in China. Carotid intima-media thickness (CIMT) and presence of carotid plaque are also related to subsequent ischemic stroke. However, the correlation between these and LAICOD is less clear. Methods— This was a community-based cross-sectional study. All subjects underwent carotid duplex ultrasonography and transcranial Doppler. Mean CIMT value of bilateral common carotid arteries was used. Plaque was defined as a focal CIMT of >1.5 mm. LAICOD in transcranial Doppler was defined by peak systolic velocity and age, and presence of turbulence or musical sound was also considered. Results— For the 537 subjects studied (mean age, 54.7±10.1 years; 46.9% males), mean CIMT was 0.74±0.12 mm, with the 75th percentile of 0.80 mm. CIMT ≥1.0 mm was identified in 13 subjects (2.4%). Plaques were detected in 79 subjects (14.7%). Compared with those without LAICOD, the 48 subjects (8.9%) with LAICOD had greater CIMTs (0.77±0.09 versus 0.73±0.12 mm; P =0.044), more with CIMT of higher quartiles ( P =0.007), and more with carotid plaques (25.0% versus 13.7%; P =0.035). However, after adjusting for confounding factors, CIMT and presence of carotid plaque were not significantly associated with LAICOD. Conclusions— The results suggest that CIMT and presence of carotid plaque probably are not independently correlated with LAICOD in Chinese community residents, which supported the existence of pathologic and pathophysiologic differences in atherogenesis of intra- and extracranial arteries.

Background and Purpose— Cerebral microbleeds (CMB) are common in stroke survivors and the community-dwelling elderly. The clinical significance of CMB in the development of depression after a stroke is unknown. This study examined the association between poststroke depression (PSD) and CMB. Methods— A cohort of 235 patients with acute lacunar stroke admitted to the stroke unit of a university-affiliated regional hospital in Hong Kong was recruited. Three months after the onset of the index stroke, a research assistant administered the locally validated 15-item Geriatric Depression Scale. PSD was defined as a Genetic Depression Scale score of ≥7. The presence and location of CMB were evaluated with MRI. Results— In comparison with the non-PSD group, PSD patients were more likely to have lobar CMB (33.3% versus 19.9%; P =0.022). Lobar CMB remained an independent predictor of PSD in the multivariate analysis, with an odds ratio of 2.08 ( P =0.032). Conclusions— The results suggest that lobar CMB may play a role in the development of PSD. The importance of CMB in the pathogenesis of depression in stroke survivors and the general elderly population warrants further investigation.

Introduction: In SAMMPRIS, the benefit of aggressive medical therapy over stenting persisted throughout the extended follow-up. It is uncertain how modern medical management could diminish stroke relapses. Method: In a prospective academic-initiated study, we recruited 40 patients (mean age 63.4±9.0 years) with acute strokes attributed to high-grade (≥70%) intracranial atherosclerotic stenosis for 3D-rotational angiograms before and after intensive medical therapy for 12 months. Treatment targets included low-density lipoprotein Results: Overall, the risk factor control reached the pre-specified intensity. Plaque thickness, and hence luminal narrowing, significantly diminished at one year (from 1.50±0.48 to 1.24±0.42mm; p Conclusion: Intracranial plaques might regress and positively remodel under intensive risk factor control. These morphologic changes might stabilise the plaques, alleviate unfavourable hemodynamics across the steno-occlusion, and hence reduce the risk of plaque rupture or platelet aggregation.

Background and Objectives: Blood pressure variability (BPV), heart rate variability (HRV) and baroreflex sensitivity (BRS) as measures of autonomic function might provide prognostic information in ischemic stroke. We aimed to study noninvasive beat-to-beat assessment of BPV, HRV and BRS in the acute phase of ischemic stroke to determine whether any of them predicted clinical outcome. Methods & Patients: Consecutive ischemic stroke patients within 7 days of symptom onset were enrolled. The frequency components of BPV and HRV by means of power spectral analysis [very low frequency (VLF; < 0.04 Hz); low frequency (LF; 0.04-0.15 Hz); high frequency (HF; 0.15-0.40 Hz); power spectral density (PSD; Results: 82 patients were recruited (mean age, 64.6 ± 9.9 years; 89.3% males). Univariate analysis showed that there were significant differences in National Institutes of Health Stroke Scale (NIHSS) at recruitment, VLF diastolic BPV, VLF, HF and PSD systolic BPV, and down ramp BEI between the good and poor outcome groups (all P < 0.05). After adjusting for NIHSS, multivariate logistic regression showed that only HF systolic BPV (OR 1.320; 95% CI, 1.050-1.659; P=0.017) and down BEI (OR 0.950; 95% CI, 0.912-0.990; P=0.014) were independently correlated with poor functional outcome. Conclusions: Beat-to beat highly variable systolic blood pressure and impaired BRS as evaluated by decreased down BEI are associated with an unfavorable functional outcome after acute ischemic stroke. Important prognostic information can be readily obtained from a short period of noninvasive hemodynamics monitoring in the acute stroke patient.

Objective: Although Magnetic Resonance Imaging (MRI) vessel wall imaging could visualize the pathology of intracranial arterial disease, signal changes are poorly interpreted due to lacking of cerebral artery specimens. Based on a MRI-histology comparison study on a series of post-mortem cerebral arteries, we aimed to examine the occurrence of hyper-, iso- and hypo-intensity on T1-weighted fat-suppressed images of MCA plaques, which might be suggestive of different plaque components. Methods: Fifty-eight pairs of MCAs were imaged at 1.5T MRI with T1-weighted Table 1: The distribution of different atherosclerotic phenotypes among MCA plaques with iso-, hyper- and hypo-intensity on T1-weighted fat-suppressed images fat-suppressed- and T2-weighted sequence. MRI was performed in the postmortem brains to scan the cross-sections of MCAs with barium expanding the artery lumen. The MCAs were then removed for histopathologic processing and atherosclerotic plaque classification, which was used as a reference standard to interpret the signal changes on MRI pictures. Results: A total of 76 MRI vessel wall images were adequate for signal changes interpretation. On T1-weighted fat-suppressed images of MCA plaques, hyper-intensity was revealed on 34 vessels (44.7%), iso-intensity on 24 vessels (31.6%) and hypo-intensity was revealed on 18 samples (23.7%). There was a trend that iso-intensity indicated lower grade atherosclerosis and hypo-intensity represented advanced atherosclerosis, while hyper-intensity was suggestive of median grade atherosclerotic plaques. Further analysis demonstrated that nearly all hypo-intensity was found to be histology-verified advanced atherosclerosis with lipid core formation. Interpretation: Signals of hypo-intensity on T1-weighted fat-suppressed images of MCA plaques may be useful in stratification of stroke patients with intracranial atherosclerosis.

Background: Intracranial arterial stenosis (ICAS) is a predominant cause of ischemic stroke in Asia. Changes of the signal intensities across ICAS lesions on time-of-flight magnetic resonance angiography (MRA) have been indicated to partially reflect the hemodynamic significance of the lesions, which we aimed to verify by correlating with cerebral perfusion features provided by CT perfusion imaging. Methods: Ischemic stroke or transient ischemic attack patients with unilateral symptomatic stenosis (≥50%) of intracranial internal carotid artery or middle cerebral artery were included in this study. Change of signal intensities across an ICAS lesion on time-of-flight MRA was calculated by the distal and proximal signal intensity ratio (SIR). Cerebral blood volume (CBV), cerebral blood flow (CBF), and mean transit time (MTT) within the middle cerebral artery territory of ipsilateral and contralateral hemispheres were evaluated on the CT perfusion images at the basal ganglia level. Relative CBV, CBF and MTT were defined as the ratios of the parameters obtained from ipsilateral and contralateral hemispheres. The relationships between SIR and CT perfusion parameters were analyzed. Results: Fifty subjects (74% male, mean age 62.84) were recruited. Overall, mean SIR was 0.77 ± 0.17. SIR of ICAS significantly, linearly and negatively correlated with ipsilateral CBV (r = -0.335, P = 0.017), CBF (r = -0.312, P = 0.028), and MTT (r = -0.301, P = 0.034), and relative MTT (r = -0.443, P = 0.001). Conclusions: Changes of the signal intensities across ICAS lesions on time-of-flight MRA may be a simple marker to reflect cerebral perfusion changes in patients with symptomatic ICAS.

Background and Purpose— Both dementia and stroke are major health problems in Chinese societies. Stroke is a frequent cause of dementia. Only a few studies have been published on poststroke dementia (PSDE), none of which has investigated a consecutive stroke cohort in Asian patient populations. The objective of this study was to examine the prevalence and clinical correlates of PSDE in Chinese stroke patients in Hong Kong. Methods— Two hundred eighty stroke patients consecutively admitted to the medical wards of a university-affiliated regional hospital were interviewed by a psychiatrist 3 months after stroke. The presence of dementia and vascular dementia was diagnosed according to the Diagnostic and Statistical Manual , 4th edition. In addition, a wide range of demographic and clinical variables were examined. Results— Fifty-five participants (20%) had PSDE. Univariate analysis found that PSDE was associated with age; level of education; prestroke Rankin Scale score; prestroke Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) score; National Institutes of Health Stroke Scale (NIHSS) best language score, dysarthria score, and total score; urinary incontinence; cortical infarct; leukoaraiosis; bilateral lesions; number of lesions; involvement of middle cerebral artery circulation; and cerebral atrophy index. Multivariate logistic regression suggested that prestroke IQCODE score, NIHSS total score, leukoaraiosis, involvement of middle cerebral artery territory, and cerebral atrophy index were independent risk factors of PSDE. After removal of 22 patients with prestroke dementia, which was defined as a prestroke IQCODE score ≥4.0, the frequency of PSDE dropped to 15.5%. Furthermore, involvement of the middle cerebral artery territory and cerebral atrophy index were replaced by level of education and bilateral lesions as independent predictors in the final logistic model. Conclusions— PSDE is common among Chinese stroke patients in Hong Kong. Its frequency is comparable to that in white populations. The clinical determinants of PSDE, after the exclusion of patients with prestroke dementia, include premorbid level of cognitive function, severity of stroke, leukoaraiosis, level of education, and bilateral lesions.

Background and Purpose— Cerebral microbleeds (MBs) detected by gradient-echo MRI are considered evidence of advanced microangiopathy with potential for further bleeding. The goal of this study was to determine whether the presence of MBs is a risk factor for subsequent intracerebral hemorrhage among patients with acute ischemic stroke. Methods— We prospectively examined patients hospitalized with acute cerebral infarction with gradient-echo T2*-weighted MRI for the presence of MBs. We recorded demographics, medical history, and stroke severity. Patients were then followed up for the development of stroke, other vascular events, and death. Results— One hundred twenty-one consecutive patients with a mean age of 67.96±10.97 years were recruited. MBs were present in 43 patients (35.5%). During follow-up of 27.15±11.68 months, 16 patients had recurrent stroke. There was no difference between patients with or without MB for the development of ischemic stroke (5 and 6 respectively, P =0.841). However, 4 patients (9.3%) with MBs and 1 patient (1.3%) without an MB had intracerebral hemorrhage during follow-up ( P =0.053). Of the 5 patients who developed subsequent intracerebral hemorrhages, 3 were treated with aspirin and 2 with anticoagulation. Two of the intracerebral hemorrhages occurred in the site where asymptomatic MBs were found at baseline. Conclusions— MBs appear to be a risk factor for subsequent intracerebral hemorrhage among patients with ischemic stroke in this small cohort of Chinese stroke patients. A large cohort study is required to confirm this observation.

Background: Success in clinical trials of intracranial atherosclerosis (ICAS) hinges upon the definition of high-risk patients. Noninvasive computational fluid dynamics (CFD) of stenotic lesions may enhance therapeutic decision-making, yet the wide hemodynamic variation may limit the snapshot data of CFD. We determined whether different physiologic parameters may change downstream cerebral hemodynamics in patients with ICAS. Methods: Based on degree of stenosis, patients were divided into a moderate (50-69%) and severe group (70-99%). CFD models were made using CTA source images of patients with symptomatic middle cerebral artery stenosis. Inlet boundary conditions were defined using three ranges (2.5, 50, and 97.5 percentiles) of systolic BP (109.2, 158, and 225 mmHg) and hematocrit (27.3, 40.2, and 48.8). According to systolic BP and hematocrit, 9 distinct scenarios were simulated. Ratio of pressure was calculated using the simulated pressure at pre- and post-stenotic segments. Ratio of shear strain rate (SSR) and velocity were assessed between throat and proximal normal segment. A linear mixed model was used for the statistical analysis of repeated simulations. Results: Among the 56 patients, 32 (57.1%) patients had moderate stenosis and 24 (42.9%) had severe stenosis. Patients with severe stenosis showed unfavorable hemodynamics in terms of ratio of pressure, velocity, and SSR comparing with moderate stenosis group. A linear mixed model revealed that ratio of pressure was predicted by systolic BP X stenosis group interaction (p = 0.036). These pressure drops were associated with systolic BP (p Conclusions: Downstream blood flow may be significantly altered by systolic BP along with severity of stenosis. As individual patient’s specific anatomy influences hemodynamics, physiologic conditions may superimpose further changes in post-stenotic blood flow in patients with ICAS.

Background — Serial changes of flow velocities of transcranial Doppler ultrasound (TCD) in symptomatic middle cerebral artery (MCA) occlusive disease may be related to the occurrence of further vascular events, but prospective data are lacking. Methods — We conducted a prospective study on patients with cerebral ischemia who were hospitalized with symptomatic MCA stenosis or occlusion. We repeated TCD examinations 6 months after the initial examinations and recorded any stroke or coronary events during this period. The changes of MCA flow velocities were categorized as normalized artery, stable artery, and progressed artery, which were determined according to the changes of MCA velocities at 6 months. Results — We studied 143 consecutive patients who had relevant MCA occlusive diseases (107 with stenosis and 36 with occlusion). At 6 months, the velocities in the MCA returned to normal in 42 patients (29%), they were stable in 80 patients (62%), and they progressed in 13 patients (9%). The number of clinical events varied significantly among the 3 groups: there were 2 patients (4.8%) with clinical events in the normal group, 11 patients (12.5%) with clinical events in the stable group, and 5 patients (38.5%) with clinical events in the progressed group ( P =0.004). The 18 recurrent events included 10 recurrent strokes, 5 transient ischemic attacks, and 3 acute coronary syndromes. Conclusions — Progression of MCA occlusive diseases is associated with an increased risk of vascular events. Further studies are required to establish the value of serial TCD examinations in predicting future clinical events.

Background and Purpose— Single subcortical infarction (SSI) may be classified as proximal SSI (pSSI) or distal SSI (dSSI) according to its location within the middle cerebral artery territory. Few studies have examined the differences in clinical outcome between the two. Our study investigated such differences in patients with pSSI or dSSI and examined their baseline characteristics and indicators for small-vessel disease. Methods— We prospectively enrolled 400 patients with SSI (208 pSSI and 192 dSSI) who had no middle cerebral artery disease on MR angiography. Data compared included clinical information, lesion size, prevalence of lacune and leukoaraiosis at baseline, National Institutes of Health Stroke Scale score and modified Rankin Scale score at discharge, and any deterioration during admission or recurrence of ischemic stroke Results— In multivariable logistic regression analysis, dSSI was independently associated with patient’s history of stroke, admission National Institutes of Health Stroke Scale score ≤3, Fazekas score ≥3, presence of lacune, but not hyperlipidemia. Patients with dSSI had shorter length of hospital stay, lower rate of functional dependence at discharge (modified Rankin Scale score ≥2), and lower deterioration or recurrence risk of ischemic stroke in 1 year. Multivariable logistic regression analysis showed that factors associated with higher deterioration or recurrence risk of ischemic stroke at 1 year included female sex, history of coronary heart disease, pSSI, and not on antithrombotics Conclusions— Compared with pSSI, patients with dSSI likely had small-vessel diseases but better clinical outcome.

Background and Purpose: External counterpulsation (ECP) is a novel noninvasive method used to augment cerebral blood flow which may benefit ischemic stroke patients. We aimed to explore the association between the degree of cerebral blood flow augmentation by ECP and clinical outcome after acute ischemic stroke. Methods: Acute ischemic stroke patients within 7 days of symptom onset were recruited into this study. On admission, bilateral middle cerebral arteries of subjects were monitored using transcranial Doppler (TCD). Flow velocity changes before, during, and after ECP were, respectively, recorded for 3 minutes. Cerebral augmentation index (CAI) was the increase in percentage of middle cerebral artery mean flow velocity during ECP compared with baseline. TCD data were analyzed based on ipsilateral or contralateral to the infarct side. Modified Rankin Scale (mRS) was evaluated 3 months, 6 months and 1 year after ischemic stroke onset. We stratified the patients into two groups (good outcome: mRS 0~2; poor outcome: mRS 3~6) at each measurement time point. Results: 72 patients were recruited (mean age, 63.8±10.7 years; 87.5% males). At month 6 and year 1 after stroke onset, univariate analysis showed that admission National Institutes of Health Stroke Scale (NIHSS) was significantly lower and ECP therapy duration was longer in good outcome group; while the ipsilateral CAI was significantly lower in good outcome group than those in poor outcome group (3.71±4.94 versus 7.73±7.66, P=0.044; 3.50±4.73 versus 8.58±7.72, P=0.015 respectively). Multivariate logistic regression showed that ipsilateral CAI and baseline NIHSS were independent predictors for a favourable outcome at these two measurement points. Conclusions: The degree of cerebral augmentation on ipsilateral to the infarct side by ECP is found to be an important predictor for long-term good outcome in acute ischemic stroke patients, in addition to the well-known prognostic factors such as NIHSS.

Intracranial atherosclerosis (ICAS) is an important cause of ischemic stroke throughout the world, accounting for ≈30% to 50% and 10% of ischemic stroke and transient ischemic attack in Asians and whites, respectively.1 Several imaging modalities, such as transcranial Doppler (TCD), magnetic resonance angiography (MRA), computed tomographic angiography (CTA), and digital subtraction angiography (DSA), are used commonly in routine clinical practice to detect and assess ICAS, as well as in selection criteria of clinical trials.2–4 Although some of these imaging modalities yield flow information, such as TCD revealing velocity data or waveform turbulence and time-of-flight MRA (TOF-MRA) depicting arterial patterns based on blood flow, most attention has been drawn to the maximal percent stenosis of the arterial lumen. The focus on severity of stenosis has been reinforced because severe (70%–99%) atherosclerotic stenosis was demonstrated as an independent predictor for stroke recurrence in the territory of the stenotic artery, with the risk of ≈20% at 1 year, in the Warfarin versus Aspirin for Symptomatic Intracranial Disease (WASID) trial.5 However, those patients with a traditionally considered moderate (50%–69%) atherosclerotic stenosis were also at considerable risk of recurrent stroke, ≈10% at 1 year in the WASID study.5,6 In more recent studies, the role of percent stenosis in predicting subsequent stroke risk has been superseded by collateral flow and hemodynamics in the same patient cohort.7,8 Characterization of the atherosclerotic lesion is also represented poorly by percentage of stenosis measured at the narrowest vessel diameter alone. Beyond the maximal luminal stenosis, many other features may reflect the characteristics of ICAS, such as plaque morphology and components, which might also be promising markers in risk stratification of patients with symptomatic ICAS.9 However, from the view of intracranial stenosis, it could also be attributed to causes …

Background: External counterpulsation (ECP) is a noninvasive method used to augment cerebral perfusion but the optimal use of ECP in ischemic stroke has not been well documented. We aim to investigate the effects of increasing ECP treatment pressure on cerebral blood flow and blood pressure (BP). Methods: We recruited 38 acute ischemic stroke patients with large artery occlusive disease and 20 healthy elderly. Mean cerebral blood flow velocities (CBFV) of bilateral middle cerebral artery were monitored using transcranial dopper. Continuous beat-to-beat BP was measured via finger cuffs. We started ECP treatment pressure from 150mmHg, then gradually increased to 187.5mmHg, 225mmHg and 262.5mmHg. CBFV and BP were recorded before ECP and during each pressure increment respectively for 3 minutes. CBFV data of patients was analyzed based on whether it was ipsilateral or contralateral to the infarct. Results: Median NIHSS of stroke patients was 5.5 and mean time after stroke onset was 5.24 days. Mean BP was significantly elevated from baseline in both groups after ECP started. BP increase percentages of two groups similarly kept augmented following raised ECP pressure and reach maximium at 262.5mmHg (patients 16.9% vs. controls 16.52% compared with baseline). Under different ECP pressures, ipsilateral mean CBFV of stroke patients increased 5.15% (150mmHg), 4.35% (187.5mmHg), 4.55% (225mmHg) and 3.52% (262.5mmHg) from baseline. All were significantly higher than baseline but did not differ among different pressures. Contralateral mean CBFV changed likewise (5.16%, 4.02%, 3.7% and 3.34% increase from baseline). Mean CBFV of controls under ECP pressures did not increase from baseline. Conclusion: The increasing treatment pressure of external counterpulsation continuously augments blood pressure but not cerebral blood flow velocity of ischemic stroke patients with large artery occlusive disease. Cerebral blood flow velocity of stroke patients significantly increases from baseline under ECP pressure of 150mmHg but it reaches a plateau as ECP pressure further raises. Among 4 ECP pressures above, 150mmHg is the optimal treatment pressure for ischemic stroke due to higher risks of hypertension-related complications in acute stroke with higher ECP pressure.

Background and Purpose: Ethnic differences have been reported between Asians and Whites in the prevalence of certain stroke subtypes. However, it is unknown if such differences exist with respect to manifestations of cerebral small vessel disease. We compared the prevalence of white matter lesions [WML], lacunes, and microbleeds between Han Chinese and White Australian individuals randomly selected from their respective populations. Methods: Magnetic resonance imaging (1.5 Tesla) was performed on participants of the Shanghai Aging Study (n=321, mean age 69±6 years) and Tasmanian Study of Cognition and Gait (n=397, mean age 72±7 years). A single expert rater recorded measures of WML, lacunes, and microbleeds. We compared lesion prevalence between age- and gender-matched subgroups from the two study population. Among all subjects (n=718), we used multivariable logistic regression to examine if ethnicity was associated with the presence of these lesions. Results: The prevalence rates of confluent WML, lacunes, and microbleeds among Chinese and Whites were 37% vs. 34% (p=0.09), 29% vs. 34% (p=0.24), and 9% vs. 11% (p=0.59), respectively. Subgroup analysis among age- and gender- matched subjects confirmed that confluent WML was more common among Chinese (38.5%) than Whites (28.4%, p=0.01). In multivariable regression, Chinese had a higher risk of confluent WML (odds ratio 1.53, 95% confidence interval 1.04-2.24, p=0.03) independent of other risk factors, but no differences were seen for lacunes and micro bleeds. Conclusion: In this population-based cross-national comparison, Chinese had a greater risk of moderate-to-severe WML than white Australians, but had a similar risk of lacunes and microbleeds.

Background and Purpose:— Intracranial arterial stenosis (ICAS) is the predominant cause of ischemic stroke or transient ischemic attack (TIA) in Asia. Change of signal intensities (SI) across an ICAS on magnetic resonance angiography (MRA) may reflect hemodynamic severity of such lesions. Methods:— In-patients with a symptomatic single ICAS of anterior circulation on 3D time-of-flight MRA were recruited. Baseline and 1-year follow-up data were collected. Signal intensity ratio (SIR) was calculated to represent change of SIs across an ICAS on maximum intensity projections: SIR=(mean post-stenotic SI - mean background SI)/(mean pre-stenotic SI - mean background SI). Acute infarct volume was measured on diffusion-weighted images (DWI). Relationships of SIR and baseline characteristics as well as 1-year outcomes were evaluated. Results:— Thirty-six subjects (86.1% males, mean age 55.0 years) were recruited. Overall, mean SIR was 0.84±0.23. Mean SIR of the 23 (63.9%) anatomically severe stenoses was insignificantly lower than the 13 (36.1%) moderate stenoses (0.80±0.23 versus 0.92±0.21, p=0.126). The median baseline infarct volume for the 28 (77.8%) subjects with lesions on DWI was 2.40 cm 3 (IQR 0.80 to 5.78). SIR and acute infarct volume were significantly, linearly and negatively correlated, Spearman correlation coefficient being -0.471 (p=0.011). Two patients (5.6%) had recurrent ischemic strokes at 1-year follow-up. SIR values or acute infarct volumes were unrelated to 1-year outcomes in this initial study. Conclusion:— Change of signal intensity across ICAS on MRA may reflect hemodynamic and functional severity of the lesion. Future studies are warranted to further verify the relationship between this index and prognosis of stroke patients.

Background and Purpose— Carotid atherosclerosis is not neglectable as a cause for stroke in China, despite of low prevalence. This study was performed to evaluate the association between its ultrasonographic markers with metabolic syndrome (MetS). Methods— This was a community-based cross-sectional study. Demographics, common vascular risk factors, and results of fasting blood analysis were collected at baseline. MetS was defined as ≥3 following conditions or receiving specific treatment: abdominal obesity, elevated triglycerides, low high-density lipoprotein cholesterol, hypertension and impaired fasting blood glucose. All subjects underwent carotid duplex ultrasonography. Mean carotid intima-media thickness (CIMT) of bilateral common carotid arteries was used as the CIMT value for a single subject. CIMT within the 4th quartile was regarded as increased CIMT. Carotid plaque was defined as a focal CIMT of >1.5 mm. Results— A total of 653 subjects (mean age 55.1±10.4; 47.2% male) were recruited. MetS was found in 188 (28.8%) subjects (30.8% in male and 27.0% in female). Mean CIMT was 0.74±0.12 mm. Increased CIMT and carotid plaques were detected in 163 (25.0%) and 95 (14.5%) subjects, respectively. In multivariate linear regression, CIMT significantly increased with increasing numbers of MetS components (P Conclusion— MetS may be independently associated with early stage but not later and advanced stages of carotid atherosclerosis in community residents in China.

Background and Purpose— Occlusive radiation vasculopathy (ORV) predisposes head-and-neck cancer survivors to ischemic strokes. Methods— We analyzed the digital subtraction angiography acquired in 96 patients who had first-ever transient ischemic attack or ischemic strokes attributed to ORV. Another age-matched 115 patients who had no radiotherapy but symptomatic high-grade (>70%) carotid stenoses were enrolled as referent subjects. Digital subtraction angiography was performed within 2 months from stroke onset and delineated carotid and vertebrobasilar circulations from aortic arch up to intracranial branches. Two reviewers blinded to group assignment recorded all vascular lesions, collateral status, and infarct pattern. Results— ORV patients had less atherosclerotic risk factors at presentation. In referent patients, high-grade stenoses were mostly focal at the proximal internal carotid artery. In contrast, high-grade ORV lesions diffusely involved the common carotid artery and internal carotid artery and were more frequently bilateral (54% versus 22%), tandem (23% versus 10%), associated with complete occlusion in one or both carotid arteries (30% versus 9%), vertebral artery (VA) steno-occlusions (28% versus 16%), and external carotid artery stenosis (19% versus 5%) (all P Conclusions— ORV angiographic features and corresponding collaterals are distinct from atherosclerotic patterns at initial stroke presentation. Clinical decompensation, despite more extensive collateralization, may precipitate stroke in ORV.

Background and Purpose— We explored the association between pulsatility index (PI) as derived from transcranial Doppler ultrasound with various measures of small vessel disease in the community. Methods— We performed transcranial Doppler and magnetic resonance imaging in 205 consecutive community-dwelling elderly subjects who were participants of the Shanghai Aging Study. We investigated the association between middle cerebral artery (MCA) PI with measures of white matter lesions (WML), lacunes, and microbleeds. Results— Multiple logistic regression found that MCA PI was associated with severe WML (odds ratio, 1.33 per 0.1 increase in PI; 95% confidence interval, 1.04–1.70; P =0.02). At optimal MCA PI cut-off, the area under curve, positive predictive value, and negative predictive value were 0.70 (95% confidence interval, 0.60–0.80), 34.9%, and 85.6%, respectively, for detection of severe WML. No association was found between MCA PI and measures of lacunes or microbleeds. Conclusions— PI correlates with WML severity. With a high negative predictive value, the chance of having severe WML with a normal PI is low. Transcranial Doppler may guide selective magnetic resonance imaging scanning for the detection of WML in the community.

Background: Radiation-induced vasculopathy (RIV) predisposes survivors of head-and-neck cancers to refractory ischemic strokes. We aimed to investigate the angiographic extent and morphological attributes of symptomatic RIV. Methods: The study was approved by the Institutional Review Board and each participant provided an informed consent. One hundred thirty patients with ischemic strokes attributed to high-grade carotid stenoses (>60%) were recruited for digital subtraction angiograms (DSA). Among the enrolled patients, 65 had prior curative intent radiotherapy for head-and-neck cancers. The remaining 65 control patients who had no radiotherapy were presumed to have atherosclerotic vasculopathy. DSA revealed both carotid and vertebro-basilar circulations from the level of aortic arch up to intracranial branches. A radiologist blind to the group assignment recorded the distribution and characteristics of both stenotic and non-stenotic lesions. Fetal variant or incompetence of the circle of Willis, if any, was also documented. Results: The baseline characteristics of RIV and control patients were comparable except a lower prevalence of hypertension and diabetes mellitus in RIV group (p were atherosclerotic. Atherosclerotic stenoses were predominantly focal, involving the internal carotid artery adjacent to the bifurcation (93/103, 90.29%). RIV stenoses, in contrast, harbored more frequently at common carotid artery (96/176, 54.55%) and was associated with more tandem lesions (29.23% vs 10.77%, p Conclusion: Radiation-induced carotid disease was frequently bilateral and associated with concurrent tandem and vertebra-basilar steno-occlusions. Fetal variant or incompetence of the Circle of Willis may potentiate further the hemodynamic insufficiency.

Background and Purpose— This study examined the association between poststroke anxiety symptoms (PSA) and frontal lobe infarcts. Methods— A cohort of 693 patients was recruited. PSA was defined as an anxiety subscale of the Hospital Anxiety and Depression Scale score of 8 or above. The presence and location of infarcts were evaluated with MRI. Results— Compared with the non-PSA group, PSA patients were more likely to have right frontal acute infarcts. Right frontal infarcts remained independent predictors of PSA in the multivariate analysis, with an odds ratio of 4.44 ( P =0.002). Conclusions— The results suggest that right frontal acute infarcts may play a role in the development of PSA.

Background and Purpose— The ABCD 2 score is able to predict the short-term risk of stroke after a transient ischemic attack/minor stroke. We aimed to explore its predictive value for long-term recurrent stroke. Methods— Consecutive patients with a transient ischemic attack/minor stroke, hospitalized during a 2-year period, were followed up to document any further stroke and death stratified by a 7-point ABCD 2 score. Result— A total of 490 patients were followed for an average of 40.5 months (SD, 10.7 months). Further stroke were identified in 76 (15.5%) patients and 62 (12.7%) patients died during follow-up. Multivariate Cox regression analysis showed that an ABCD 2 score >4 was found to be an independent risk factor for further stroke (hazard ratio, 2.27; 95% CI, 1.36 to 3.80) and for death (hazard ratio, 1.68; 95% CI, 0.99 to 2.85). Conclusions— In addition to predicting short-term stroke risk, ABCD 2 score is a useful tool to predict long-term stroke risk after a transient ischemic attack or minor ischemic stroke.

Background and Purpose— Concurrent atherosclerosis of the intracranial and extracranial cerebrovascular system is common in Asians. The typical lesion patterns and the mechanisms of stroke in patients with concurrent stenoses are unclear. This study aimed to determine these stroke features of such patients in Hong Kong. Methods— We conducted a cross-sectional cohort study in a university hospital from January 2002 to December 2003. Consecutive Chinese patients with acute ischemic stroke underwent CT brain, MRI brain (with MR angiography and diffusion-weighted imaging sequences), and carotid duplex. Results— In total, 251 patients were included in the analysis. Of these, 109 (43%) had concurrent stenoses. Patients who had concurrent stenoses, as compared with those without concurrent stenoses, had more symptomatic stenoses (84% versus 58%; OR, 4.0; 95% CI, 2.1 to 7.3; P P =0.007), more multiple diffusion-weighted imaging lesions (55% versus 37%; OR, 2.1; 95% CI, 1.3 to 3.4; P =0.005), and more infarcts in the territory of the leptomeningeal branches of middle cerebral artery (26% versus 13%; OR, 2.2; 95% CI, 1.2 to 4.3; P =0.01). In multivariate regression analysis, smoking; prior stroke; the presence of concomitant pial infarct, pial infarct, and borderzone infarcts; multiple diffusion-weighted imaging lesions; and symptomatic stenoses were significantly associated with concurrent stenoses. Among patients with concurrent stenoses, those who had tandem lesions, as compared with those who had nontandem lesions, had more perforating artery infarct and borderzone infarcts (27% versus 8%; OR, 4.3; 95% CI, 0.9 to 19.8; P =0.04); more concomitant pial infarct, pial infarct, and borderzone infarcts (18% versus 0%; P =0.02), and more multiple diffusion-weighted imaging lesions (65% versus 23%; OR, 6.2; 95% CI, 2.2 to 17.2; P Conclusions— Concomitant perforating artery infarct, pial infarct, and borderzone infarcts; multiple diffusion-weighted imaging lesions, and infarcts in the leptomeningeal branches of the middle cerebral artery were more common in patients with concurrent stenoses, especially those with tandem lesions. This study suggested that the combination of hemodynamic compromise attributable to concurrent stenoses and artery-to-artery embolization is a common stroke mechanism in these patients.

Background and Purpose— 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. Methods— 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. Results— 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 χ 2 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. Conclusions— 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.

Background and Purpose—Cerebral white matter changes (WMC) and lacunar infarct are both believed to be consequence of small vessel disease. Whether the extent of WMC affect the type and degree of cognitive impairment in patients with lacunar infarct is not clear. The study was undertaken to determine if WMC influences cognition in patients with lacunar infarcts.Methods—We recruited consecutive patients who were admitted to the acute stroke unit because of acute lacunar infarcts, mainly documented by diffusion-weighted magnetic resonance imaging. WMC were measured qualitatively and quantitatively. Patients were divided into quartiles according to the distribution of the volume of WMC. Cognition was assessed 12 weeks after stroke by psychometric tests (Chinese version of Mini-Mental State Examination [MMSE], Alzheimer’s Disease Assessment Scale-cognition [ADAS-cog], Mattis Dementia Rating Scale-Initiation/ Perseveration subscale [MDRS I/P]) and was compared between patients with varying severity of WMC. Multivariate linear regression analysis was performed to find variables that influenced performance in the psychometric tests.Results—Among the 94 included patients with acute lacunar infarcts, those patients (n=25) within the highest quartile of WMC were older, had more lacunar infarcts, more severe stroke, and lower prestroke cognitive function compared with those with less WMC. In addition, their performances in psychometric tests were significantly more impaired. Multivariate linear regression analysis revealed that WMC significantly influenced performance in MDRS I/P. WMC did not independently influence performance in MMSE and ADAS-cog.Conclusions—Extent of WMC appears to be associated with executive dysfunction in stroke patients with lacunar infarcts. Further large prospective studies with extensive scales of executive function testing are required to confirm this issue.

Background and Purpose —Intracranial large-artery occlusive disease is the predominant vascular lesion found in stroke patients of Asian, African, and Hispanic ancestry, making it numerically perhaps the most common vascular cause of stroke in the world. Relatively little is known about the clinical significance of finding such lesions. We investigate whether the presence and the extent of these vascular lesions help predict outcome after stroke. Methods —On the basis of transcranial Doppler of the intracranial arteries with supplementary duplex ultrasound of the carotid arteries, we determined the number of occlusive arteries in the craniocervical circulation of consecutive patients who were hospitalized for acute cerebral ischemia. Patients were followed for 6 months for further vascular events (including transient ischemic attack, stroke, and acute coronary syndrome) or death. Results —Among 705 consecutive Chinese patients studied, occlusive arteries were found in 345 patients (49%): 258 patients (37%) had intracranial lesions only, 71 (10%) had both extracranial and intracranial lesions, and 16 (2.3%) had extracranial lesions only. Sixty-three (18%) of the 345 patients with occlusive arteries and 35 (9.7%) of the 360 patients without occlusive arteries had further vascular event or death within 6 months. The risk of vascular events or death increased rapidly with rising numbers of occlusive arteries, after adjustment for vascular risk factors and stroke severity (adjusted odds ratio [OR] 1.25 per occlusive artery, 95% CI 1.12 to 1.39). Other independent risk factors included age (OR 1.03 per year of age, 95% CI 1.01 to 1.05) and atrial fibrillation (OR 3.00, 95% CI 1.40 to 6.69). Conclusions —In patients with predominantly intracranial large-artery occlusive disease, the presence and the total number of occlusive arteries in the craniocervical circulation predict further vascular events or death within 6 months after stroke. Transcranial Doppler ultrasound is an important investigation for the evaluation of patients with stroke in populations at risk of intracranial atherosclerotic disease.

Our purpose was to assess the feasibility and risk of performing a double-blind placebo-controlled study of low-molecular-weight heparin in the treatment of acute ischemic stroke. Fifty-five patients were treated within 48 hours of stroke onset. Pretreatment computed tomography was performed to rule out cerebral hemorrhage. Fraxiparine (6000 IU per day) was given subcutaneously for 7 days. No adverse reaction was encountered during the treatment period. At 3 months, 26 patients were independent, 21 moderately disabled, 4 severely disabled, and 4 dead. It would be safe and practical to conduct a clinical trial on the use of Fraxiparine in the treatment of acute ischemic stroke.

To the Editor: Norrving and Adams, in the recent series of articles entitled “Advances in Stroke 2005,” clearly state the evidence for organized stroke care as inpatients after hospital admission.1 It is clear from their review that stroke unit care confers major survival benefits and reductions in disability. We …