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There may be different mechanisms underlying internal (IBZ) and cortical (CBZ) borderzone infarcts in intracranial atherosclerotic stenosis. In 84 patients with symptomatic, 50-99% atherosclerotic stenosis of M1 middle cerebral artery (MCA-M1) with acute borderzone infarcts in diffusion-weighted imaging, we classified the infarct patterns as isolated IBZ (n = 37), isolated CBZ (n = 31), and IBZ+CBZ (n = 16) infarcts. CT angiography-based computational fluid dynamics models were constructed to quantify translesional, post-stenotic to pre-stenotic pressure ratio (PR) in the MCA-M1 lesion. Those with IBZ infarcts were more likely to have a low PR (indicating impaired antegrade flow across the lesion) than those without (p = 0.012), and those with CBZ infarcts were more likely to have coexisting small cortical infarcts (indicating possible embolism) than those without (p = 0.004). In those with isolated IBZ or CBZ infarcts, low PR was independently associated with isolated IBZ infarcts (adjusted odds ratio = 4.223; p = 0.026). These two groups may also have different trajectories in the stroke risks under current medical treatment regimen, with a higher risk of same-territory ischemic stroke recurrence within 3 months in patients with isolated IBZ infarcts than isolated CBZ infarcts (17.9% versus 0.0%; log-rank p = 0.023), but similar risks later in 1 year., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

We aimed to investigate the roles of antegrade residual flow and leptomeningeal collateral flow in sustaining cerebral perfusion distal to an intracranial atherosclerotic stenosis (ICAS). Patients with apparently normal cerebral perfusion distal to a symptomatic middle cerebral artery (MCA)-M1 stenosis were enrolled. Computational fluid dynamics models were built based on CT angiography to obtain a translesional pressure ratio (PR) to gauge the residual antegrade flow. Leptomeningeal collaterals (LMCs) were scaled on CT angiography. Cerebral perfusion metrics were obtained in CT perfusion maps. Among 83 patients, linear regression analyses revealed that both translesional PR and LMC scale were independently associated with relative ipsilesional mean transit time (rMTT). Subgroup analyses showed that ipsilesional rMTT was significantly associated with translesional PR ( p  < 0.001) rather than LMC scale in those with a moderate (50-69%) MCA stenosis, which, however, was only significantly associated with LMC scale ( p  = 0.051) in those with a severe (70-99%) stenosis. Antegrade residual flow and leptomeningeal collateral flow have complementary effects in sustaining cerebral perfusion distal to an ICAS, while cerebral perfusion may rely more on the collateral circulation in those with a severe stenosis.

Background: Short course of dual antiplatelet therapy for early secondary prevention is a promising treatment for patients with minor stroke or transient ischemic attack at high risk of recurrence., Methods: We examined the efficacy and safety of dual antiplatelets in patients with transient ischemic attack or minor stroke, defined as National Institute of Health Stroke Scale scores 0-3, in a subgroup analysis of Clopidogrel plus aspirin versus Aspirin alone for Reducing embolization in patients with acute symptomatic cerebral or carotid artery stenosis (CLAIR) study. Microembolic signals on transcranial Doppler monitoring was used as surrogate marker for recurrent stroke risk. Patients with ≥1 microembolic signals at baseline were randomized to receive dual therapy (aspirin 75-160 mg daily and clopidogrel 300 mg day 1 then 75 mg daily) or monotherapy (aspirin 75-160 mg daily) for seven-days., Results: Sixty-five of 100 patients recruited had transient ischemic attack or minor stroke: 30 received dual therapy and 35 received monotherapy. Mean onset-to-randomization was 2·3 days in dual therapy group and 3·2 days in monotherapy group (P = 0·03). At day 7, the proportion of patients with ≥1 microembolic signals was 9 of 29 patients in dual therapy group and 18 of 34 patients in monotherapy group (adjusted relative risk reduction 41·4%, 95% CI 29·8-51·1, P < 0·001). The median number of microembolic signals on day 7 was 0 in dual therapy group and 1·0 in monotherapy group (P = 0·046). No patients had intracranial or severe systemic hemorrhage., Conclusions: Early dual therapy with clopidogrel and aspirin reduces microembolic signals in patients with minor ischemic stroke or transient ischemic attack, without causing significant bleeding complications., (© 2013 The Authors. International Journal of Stroke © 2013 World Stroke Organization.)

Background: Dual antiplatelet therapy with clopidogrel and aspirin reduces the presence and number of microembolic signals in patients with large artery disease. However, whether it is effective in patients with intracranial disease alone remains uncertain. We performed a subgroup analysis of the The CLopidogrel plus Aspirin for Infarction Reduction (CLAIR in acute stroke or transient ischemic attack patients with large artery stenosis and microembolic signals) study of only patients with intracranial occlusive disease, excluding those with extra cranial disease., Methods: CLAIR was a randomized-controlled, open-label, multicenter clinical trial with blinded outcome evaluation, which recruited patients with symptoms of ischemic stroke or transient ischemic attack within seven-days of onset, with large artery stenosis verified by transcranial Doppler and carotid ultrasound, and with microembolic signals detected by transcranial Doppler recording. All patients were randomized to receive clopidogrel plus aspirin daily for seven-days (dual treatment), or aspirin alone for seven-days (monotherapy). Repeated transcranial Doppler recordings for microembolic signals were made on day one, two, and seven. This subgroup study only analyzed the patients with purely intracranial large artery disease and excluded those with extra cranial stenosis., Results: There were 70 patients recruited with purely intracranial stenosis, 34 in the dual treatment group and 36 in the monotherapy group. The proportion of the patients with positive emboli at day seven in the dual treatment group was significantly lower than that in the monotherapy group (relative risk reduction 56·5%, 95% confidence interval 2·5-80·6; P = 0·029). The number of emboli in the dual treatment group decreased significantly at day two (P = 0·043) and day seven (P = 0·018) compared with the monotherapy group. After adjustment for the number of emboli at day one, the effect of dual treatment was still significant for the reduction of presence (relative risk reduction 56·0%; 95% confidence interval 5·4-79·6; P = 0·036) and number (adjusted mean difference -0·9; 95% confidence interval -1·5 to -0·3; P = 0·004) of positive emboli at day seven., Conclusions: Dual treatment with clopidogrel and aspirin for seven-days is more effective than aspirin alone to reduce microembolic signals in patients with intracranial arterial stenosis., (© 2012 The Authors. International Journal of Stroke © 2012 World Stroke Organization.)

Background: International guidelines recommend oral anticoagulation in patients with atrial fibrillation according to their level of stroke risk. This study aimed to determine oral anticoagulation use in atrial fibrillation patients with recent ischemic stroke and examine factors that impact such management in China., Methods: Among the patients with acute ischemic stroke (n = 4782) from the China QUality Evaluation of Stroke Care and Treatment study, a multicenter, prospective, 62-hospital registry in China, there were 499 (10%) (mean age 70 ± 12 years, 49% female) with documented atrial fibrillation with outcome data over 12 months of follow-up. Logistic regression analysis was used to identify the independent predictors of oral anticoagulation use in these patients., Results: Of the 499 stroke patients with atrial fibrillation, oral anticoagulation use was 20% overall but varied from 8% prestroke and 11% in-hospital (poststroke), to 13% and 10% at three-months and 12 months, respectively. Oral anticoagulation use was independently associated with younger age (odds ratio 0.95, 95% confidence interval 0.93-0.97, P < 0.001), nonmanual occupation (odds ratio 0.44, 95% confidence interval 0.25-0.80, P = 0.006), and less cardiovascular risk factors (odds ratio 0.81, 95% confidence interval 0.68-0.96, P = 0.02)., Conclusions: These data indicate oral anticoagulation use is lower in stroke patients with atrial fibrillation in China than that in Western countries, being applied more often in those of younger age, nonmanual occupation, and having less cardiovascular risk factors., (© 2011 The Authors. International Journal of Stroke © 2011 World Stroke Organization.)

Background and Purpose: Of the stroke types, intracerebral hemorrhage is the most debilitating and fatal. The aim of the current study was to determine factors that influence the severity and in-hospital mortality after primary intracerebral hemorrhage., Methods: Data were collected retrospectively on 1268 patients with primary intracerebral hemorrhage admitted to stroke units at participating hospitals in Guangzhou between January 2005 and August 2008. Logistic regression analysis was used to determine factors associated with severity on admission and in-hospital mortality., Results: Of the 1268 patients, 20·4% were reported to have a severe stroke on admission, and the in-hospital mortality rate was 12·5%. Severity on admission was strongly associated with Glasgow Coma Scale score on admission (odds ratio = 0·89, 95% confidence interval 0·85-0·94) and hematoma location. Notably, basal ganglia hemorrhages were associated with increased severity (odds ratio = 1·40, 95% confidence interval 1·03-1·90), and cerebellar hemorrhages were associated with reduced severity (odds ratio = 0·29, 95% confidence interval 0·10-0·84). In-hospital mortality was not only correlated with Glasgow Coma Scale score on admission (odds ratio = 0·79, 95% confidence interval 0·74-0·84) and basal ganglia location (odds ratio = 0·47, 95% confidence interval 0·26-0·83), but also with dysnatremia (odds ratio = 1·91, 95% confidence interval 1·08-3·40) and comorbidities such as upper gastrointestinal hemorrhage (odds ratio = 2·28, 95% confidence interval 1·33-3·91), pneumonia (odds ratio = 3·50, 95% confidence interval 2·17-5·63), urinary incontinence (odds ratio = 2·22, 95% confidence interval 1·40-3·51), and renal dysfunction (odds ratio = 2·28, 95% confidence interval 1·42-3·65)., Conclusion: Glasgow Coma Scale score and hematoma locations were independently associated with severity on admission and in-hospital mortality after primary intracerebral hemorrhage. The study also highlights the deleterious effect of comorbidities on in-hospital mortality following primary intracerebral hemorrhage in China., (© 2011 The Authors. International Journal of Stroke © 2011 World Stroke Organization.)

Despite extensive research into poststroke depression (PSD), the role played by lesion location in the pathogenesis of PSD remains uncertain. The aim of this study was to estimate the magnetic resonance imaging (MRI) correlates of PSD in Chinese patients with first or recurrent stroke. A total of 591 patients with acute ischemic stroke admitted to the acute stroke unit of a university-affiliated regional hospital in Hong Kong were recruited. A psychiatrist assessed all the patients 3 months after the stroke. The psychiatrist used the Structured Clinical Interview for Diagnostic and Statistical Manual, fourth edition (DSM-IV) to confirm whether the patients met the criteria of a depressive disorder. In addition, a host of demographic, clinical, and radiological variables were examined. A tota; of 475 and 116 patients had first and recurrent strokes, respectively. In all, 75 (12.7%) patients received a diagnosis of PSD. In univariate analysis of the MRI findings, the presence of infarcts in the frontal subcortical circuits ([FSC], 66.7% vs 53.3%) was significantly associated with PSD (P = .03) compared to the patients without PSD. The FSC infarct-PSD association remained significant (odds ratio = 2.6) in subsequent logistic regression analysis after adjusting for gender, history of depression, neurological impairment, level of social support, and major life events. In conclusion, FSC infarcts are independent predictors of PSD. Further work is needed to clarify whether these infarcts have an impact on the clinical presentation, treatment responses, and prognosis of PSD.

Environmental and genetic factors may both affect the risk of vascular cognitive impairment developing after a stroke. To identify factors affecting this risk, the cognitive status of 121 patients was examined 3 months after an ischemic stroke. In all patients and in 270 control subjects, 7 polymorphisms reported to affect risk of vascular ischemic disease were genotyped. In 51 patients (42.1%), vascular cognitive impairment resulted, defined by a Mini-Mental State Examination score of less than 24. These patients were older and more likely to be women. Alleles of none of the polymorphisms differed between patients with or without vascular cognitive impairment, except for glutamate-cysteine ligase modifier (GCLM) (odds ratio = 2.8, P = .006). When all stroke patients were considered, the GCLM genotype did not affect Mini-Mental State Examination scores. Testing the GCLM genotype in an independent group of stroke patients may determine whether this association with vascular cognitive impairment is genuine.

Although the Virchow's triad on thrombosis includes reduced blood flow as a factor, there has been relatively little data on the importance of total cerebral blood flow on the risk of subsequent stroke. In the current study, we investigate whether total cerebral blood flow helps predict stroke recurrence. Extracranial arterial blood flow volume estimated by color velocity imaging quantification ultrasound (CVIQ) is an index of cerebral blood flow measurement. We performed a cohort study of 210 consecutive acute stroke patients. Patients were studied with transcranial Doppler and duplex ultrasound for intra- and extracranial large artery disease within 3 days of symptom onset. The association between the risk of recurrent stroke and CVIQ was analyzed with Cox proportional hazards model. Thirty-nine patients (17.7%) developed an ischemic stroke during a mean follow-up of 47.5 months. The mean extracranial blood flow volume was significantly lower for patients who had a recurrent stroke than those without (594.4+/-130.3 versus 683.8+/-176.9 mL/min; P=0.003). In a Cox proportional hazards model adjusting for potential confounding variables, extracranial blood flow volume (hazard ratio (HR) for lowest tertile, 4.1; 95% confidence interval (CI), 1.5 to 11.0) along with male sex (HR, 2.5; 95% CI, 1.3 to 5.1), diabetes (HR, 2.5; 95% CI, 1.2 to 5.0) and large artery stenosis (HR, 2.2; 95% CI, 1.1 to 4.4) were independent predictors for stroke recurrence. Our data indicated that patient with low amount of blood flow to the brain is at risk of recurrent stroke.