摘要:

Background and Purpose—To identify risk factors for subarachnoid hemorrhage (SAH) and intracerebral hemorrhage, we designed a case-control study of men and women 18 to 49 years of age (the Hemorrhagic Stroke Project [HSP]). This report focuses on SAH.Methods—Patients were recruited from 44 hospitals in the United States. Cases with SAH must have had a ruptured aneurysm documented by angiography or surgery. Two controls, identified by random digit dialing and matched to each patient for age, sex, race, and telephone exchange, were sought for each case subject.Results—Between 1994 and 1999, 425 patients with SAH were enrolled in HSP, and 312 cases met the criteria for aneurysmal SAH. The present analyses also included 618 matched controls. Of the 312 cases, 66% were current cigarette smokers compared with 30% of controls (adjusted odds ratio [OR], 3.73; 95% CI, 2.67 to 5.21). Cocaine use within the previous 3-day period was reported by 3% of cases and no controls (bivariate exact OR, 24.97; 95% exact CI, 3.95 to ∞; adjusted estimate not calculable). Other independent risk factors in the multivariable model included hypertension (adjusted OR, 2.21; 95% CI, 1.48 to 3.29), low body mass index (OR, 1.59; 95% CI, 1.08 to 2.35), primary family history of hemorrhagic stroke (OR, 3.83; 95% CI, 1.73 to 8.46), caffeine in pharmaceutical products (OR, 2.48; 95% CI, 1.19 to 5.20), lower educational achievement (OR, 2.36; 95% CI, 1.44 to 3.87), and nicotine in pharmaceutical products (adjusted estimate not calculable).Conclusions—Aneurysmal SAH may be largely a preventable disease among the young and middle-aged because several prevalent risk factors can be modified by medication (eg, hypertension) or behavioral change (eg, cigarette smoking, cocaine use). The association of caffeine and nicotine in pharmaceutical products and aneurysmal SAH warrants further study.

ISSN:0039-2499    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background and Purpose—We sought (1) to identify early metabolic markers for the development of (ir)reversible neurological deficits and cerebral infarction in subarachnoid hemorrhage (SAH) patients by using the microdialysis technique and (2) to evaluate the influence of intracerebral hemorrhage (ICH) on microdialysis parameters.Methods—We performed a prospective study of 44 SAH patients with acute focal neurological deficits (AFND) occurring acutely with SAH (due to ICH) or directly after surgery (due to clip stenosis, thromboembolism, or early edema). Fifty-one nonischemic SAH patients served as a control group. A microdialysis catheter was inserted into the vascular territory of the aneurysm after clipping. The microdialysates were analyzed hourly for extracellular glucose, lactate, lactate/pyruvate ratio, glutamate, and glycerol with a bedside analyzer. Microdialysis-related CT findings were evaluated for the presence of ICH and cerebral infarction. Reversibility of neurological symptoms after 4 weeks and 6- and 12-month outcomes were assessed.Results—In patients with AFND, cerebral metabolism was severely disturbed when microdialysis started compared with controls (P<0.005). Infarction on CT was associated with pathological microdialysis parameters (P<0.002) and development of a fixed deficit (P<0.003), while the presence of ICH alone was not. A secondary neurological deterioration of AFND patients (n=11) was reflected by preceding (0 to 20 hours) changes of microdialysate concentrations.Conclusions—In the presence of ICH, pathological microdialysis values may indicate reversible tissue damage. Extreme microdialysis values and pathological microdialysis concentrations that further deteriorate 2-fold are highly indicative of the development of cerebral infarction and permanent neurological deficits. Therefore, the analysis of relative changes of microdialysis parameters is crucial for the detection of ischemia in SAH patients.

ISSN:0039-2499    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background and Purpose—The goal of this study was to examine the effects of hypertonic saline on cerebral blood flow (CBF) in poor-grade patients with subarachnoid hemorrhage.Methods—We administered 23.5% hypertonic saline (2 mL/kg IV) 1 time to 10 patients, 2 times to 7 patients, and 3 times to 1 patient. All patients had transcranial Doppler (TCD), intracranial pressure (ICP) monitoring, and analysis of serum sodium and osmolality; 6 had xenon CT (XeCT). Data were used to characterize the changes in CBF, cerebral vascular resistance (CVR), ICP, cerebral perfusion pressure (CPP), and potential rheological mechanisms of action.Results—In the first treatment episode, CPP increased 26.8% (P=0.0003, at 28.3 minutes) from a rise in mean arterial blood pressure (ABP) of 10.5% (P=0.02, at 22.2 minutes) and a fall in ICP (−74.7%,P=0.002, at 60.0 minutes). Flow velocity (FV) of the middle cerebral artery increased 70.8% (P=0.00005, at 20.0 minutes), resulting in a corresponding fall in estimated CVR (−26.6%,P=0.01, at 16.3 minutes). The half-lives of effects on ABP, CPP, ICP, FV, and estimated CVR were 20.0, 53.6, 139.1, 42.7, and 27.1 minutes, respectively. In the second treatment episode, all these parameters had the same response except estimated CVR, which did not reach statistical significance. XeCT confirmed the increase in CBF (22.9%,P=0.02) without regional differences. A fall in CBF after hypertonic saline was identified in only a single region of interest in a patient in whom baseline flow was low but not infarcted. Serum sodium rose by 11.4 and 8.8 mmol/L, and osmolality rose by 26.7 and 16.3 mosm/L in the first and second treatment episodes, respectively. Hemoglobin decreased by 0.7 and 0.6 g/L and hematocrit decreased by 1.9% and 2.4% in the first and second treatment episodes, respectively.Conclusions—We found that 23.5% hypertonic saline increases CBF in poor-grade patients with subarachnoid hemorrhage. These effects are associated with improved indexes of blood rheology. Potential therapeutic benefits are discussed.

ISSN:0039-2499    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background and Purpose—Our aim in this study was to assess the incidence and determining factors of angiographic recurrences after endovascular treatment of aneurysms.Methods—A retrospective analysis of all patients with selective endosaccular coil occlusion of intracranial aneurysms prospectively collected from 1992 to 2002 was performed. There were 501 aneurysms in 466 patients (mean±SD age, 54.20±12.54 years; 74% female). Aneurysms were acutely ruptured (54.1%) or unruptured (45.9%). Mean±SD aneurysm size was 9.67±5.91 mm with a 4.31±1.97-mm neck. The most frequent sites were basilar bifurcation (27.7%) and carotid ophthalmic (18.0%) aneurysms. Recurrences were subjectively divided into minor and major (ideally necessitating re-treatment). The most significant predictors of angiographic recurrence were determined by logistic regression. These results were confirmed by &khgr;2,ttests, or ANOVAs followed, when appropriate, by Tukey’s contrasts.Results—Short-term (≤1 year) follow-up angiograms were available in 353 aneurysms (70.5%) and long-term (>1 year) follow-up angiograms, in 277 (55%), for a total of 383 (76.5%) followed up. Recurrences were found in 33.6% of treated aneurysms that were followed up and that appeared at a mean±SD time of 12.31±11.33 months after treatment. Major recurrences presented in 20.7% and appeared at a mean of 16.49±15.93 months. Three patients (0.8%) bled during a mean clinical follow-up period of 31.32±24.96 months. Variables determined to be significant predictors (P<0.05) of a recurrence included aneurysm size ≥10 mm, treatment during the acute phase of rupture, incomplete initial occlusions, and duration of follow-up.Conclusions—Long-term monitoring of patients treated by endosaccular coiling is mandatory.

ISSN:0039-2499    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background and Purpose—The presence of carotid stenosis (CS) in a patient with lacunar stroke is usually considered an indication of atherosclerosis and not directly related to the development of this infarction subtype. This study was designed to determine the relationship between CS and lacunar infarction (LI) and to assess the differences between single and multiple LIs.Methods—We classified 330 patients with a first-ever cerebral infarction in the carotid territory into LI and non-LI (NLI) groups. In the LI group, patients with a single LI and those with multiple LIs were identified. In this last subgroup, 2 patterns were identified: 1 subtype with lacunar lesions distributed in both cerebral hemispheres, and another with lesions predominantly in 1 hemisphere.Results—In the LI group, isolated CS was significantly more frequent on the homolateral side than on the contralateral side (odds ratio [OR], 5.5; 95% CI, 1.2 to 23;P=0.03). A significant relationship between the pattern of distribution of the infarctions in only 1 hemisphere and homolateral CS >70% was observed (OR, 4.4; 95% CI, 0.9 to 19;P=0.03). In a multivariate analysis, the following variables were found to predict unilateral multiple LI: left ventricular hypertrophy (OR, 9.1; 95% CI, 2.5 to 33.6) and homolateral CS >75% (OR, 14.4; 95% CI, 2.0 to 99.6).Conclusions—The significant incidence of isolated ipsilateral CS in patients with LI located in the carotid territory and the relationship of CS to ipsilateral multiple LI suggest that CS has a very important role in the development of LI.

ISSN:0039-2499    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background and Purpose—Inflammation and hypercoagulability contribute to the development of acute cerebral ischemia. Both can be mediated by the CD40 system. This study investigated whether the CD40 system and related mediators are upregulated in patients with transient ischemic attack (TIA) or stroke.Methods—Seventeen patients with TIA, 60 patients with complete stroke, and 15 control subjects were investigated. CD154 and P-selectin were analyzed on platelets and CD40 on monocytes during and 3 months after acute cerebral ischemia by double-label flow cytometry. Blood concentrations of soluble CD154 and monocyte chemoattractant protein-1 (MCP-1) were evaluated.Results—Our main findings are as follows: (1) patients with acute cerebral ischemia showed a significant increase of CD154 on platelets and CD40 on monocytes compared with controls; (2) plasma levels of soluble CD154 were significantly higher in these patients; (3) these patients had significantly higher numbers of prothrombotic platelet-monocyte aggregates; (4) the chemoattractant MCP-1 was significantly elevated in cerebral ischemia; and (5) at 3 months’ follow-up, upregulation of CD154 still persisted in patients with previous acute cerebral ischemia.Conclusions—Patients with acute cerebral ischemia show upregulation of the CD40 system, which might contribute to the known proinflammatory, proatherogenic, and prothrombotic milieu found in these patients.

ISSN:0039-2499    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background and Purpose—Patients with carotid artery occlusion (CAO) and ipsilateral transient ischemic attack (TIA) can have lasting cognitive impairment, despite the recovery of focal neurological deficits. We sought to assess whether cognitive impairment in these patients is associated with hemodynamic compromise and/or impaired cerebral metabolism.Methods—In 39 consecutive patients with a TIA associated with an angiographically proven occlusion of the carotid artery, we examined (1) cognitive functioning, (2) cerebrovascular reserve capacity of the middle cerebral artery ipsilateral to the CAO as measured by transcranial Doppler ultrasound, and (3) metabolic ratios as measured by1H-MR spectroscopy in the centrum semiovale ipsilateral to the symptomatic CAO. Findings were compared with those in healthy control subjects.Results—As a group, patients were cognitively impaired. Mean CO2reactivity and the mean ratio ofN-acetyl aspartate to creatine were decreased. In approximately one third of patients, lactate was present in noninfarcted regions. The presence of lactate proved to be a stronger correlate of cognitive impairment than MRI-detected lesions (&bgr;=0.41 versus &bgr;=0.15). Cognitive impairment did not correlate with CO2reactivity or the ratio ofN-acetyl aspartate to creatine.Conclusions—This exploratory study in patients with CAO and ipsilateral TIA showed that1H-MR spectroscopy–detected lactate in noninfarcted regions is a better indicator of cognitive impairment than MRI-detected lesions. Cognitive impairment did not correlate with CO2reactivity.

ISSN:0039-2499    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background and Purpose—Identifying core, irreversibly infarcted tissue and salvageable penumbral tissue is crucial to informed, physiologically guided decision making regarding thrombolytic and other interventional therapies in acute ischemic stroke. Pretreatment perfusion MRI offers promise as a means to differentiate core from penumbral tissues.Methods—Diffusion-perfusion MRIs were performed before treatment and on day 7 in patients undergoing successful vessel recanalization with intra-arterial thrombolytic therapy. Perfusion maps of the time to peak of the residue function (Tmax) were generated after deconvolution of an arterial input function. Initial perfusion abnormalities and final infarct regions were outlined by hand. Posttreatment images were coregistered to the pretreatment study. Voxel-by-voxel and volume analyses were performed to identify thresholds of perfusion abnormalities that best predict core, irreversibly infarcted tissue.Results—Fourteen patients (4 men, 10 women) with vessel recanalization were studied. Mean age was 73 years, and median entry National Institutes of Health Stroke Scale score was 12. Mean time from symptom onset to start of intra-arterial infusion was 245 minutes and to recanalization was 338 minutes. With a voxel-by-voxel analysis, Tmax≥6 and ≥8 seconds (sensitivity, 71% and 53%; specificity, 63% and 80%) correlated most highly with day 7 final infarct. With a volume analysis, Tmax≥6 and ≥8 seconds (r2=0.704 andr2=0.705) correlated most highly with day 7 final infarct.Conclusions—Perfusion-weighted imaging measures of ischemia severity accurately differentiate irreversibly injured core from penumbral, salvageable tissue. The best threshold for identifying core infarcted tissue is adjusted Tmaxof ≥6 to 8 seconds.

ISSN:0039-2499    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background and Purpose—The aim of this study was to determine the effectiveness of pioglitazone compared with placebo for improving insulin sensitivity among nondiabetic patients with a recent transient ischemic attack (TIA) or nondisabling ischemic stroke and impaired insulin sensitivity.Methods—Eligible subjects were men and women >45 years of age who had no history of diabetes, fasting glucose <7.0 mmol/L, and impaired insulin sensitivity according to an index calculated from insulin and glucose blood levels obtained during an oral glucose tolerance test. Eligible subjects were randomized to pioglitazone 45 mg/d or placebo. After 3 months of therapy, the glucose tolerance test was repeated.Results—Between July 2000 and June 2001, we performed oral glucose tolerance tests on 75 patients with no history of diabetes, among whom 36 (50%) were found to have impaired insulin sensitivity and fasting glucose <7.0 mmol/L. Among these 36, 20 consented to the trial. Patients assigned to pioglitazone (n=10) and placebo (n=10) were similar in insulin sensitivity, age, obesity, and index event (stroke compared with TIA), but patients assigned to pioglitazone were less likely to be male (4 compared with 9). The mean proportional increase in insulin sensitivity was 62% among patients assigned to pioglitazone compared with a −1% decline among patients assigned to placebo (P=0.0006). Mean C-reactive protein concentration declined from 0.30 to 0.20 mg/L among patients assigned to pioglitazone and increased from 0.41 to 0.45 mg/L among patients assigned to placebo (P=0.06 for comparison of mean change).Conclusions—Pioglitazone is effective for improving insulin sensitivity among patients with recent TIA or stroke and impaired insulin sensitivity.

ISSN:0039-2499    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background and Purpose—Recombinant tissue plasminogen activator (rtPA; Actilyse) is not as widely used in clinical practice as it could be. Have new data since 1995 strengthened the evidence sufficiently to justify more widespread use of rtPA?Methods—We performed a sequential year-to-year cumulative meta-analysis of randomized controlled trials of rtPA in acute ischemic stroke.Results—Although the amount of data has doubled since 1995, effect estimates for key outcomes remain imprecise, and significant between-trial heterogeneity persists. In the most recent analysis, rtPA up to 6 hours after stroke yielded 55 fewer dead or dependent people per 1000 treated (95% CI, 18 to 92) despite some risk (nonsignificant excess of 19 deaths per 1000 patients treated; 95% CI, 6 fewer to 48 more). Severity of stroke, patient age, and aspirin use were possible sources of heterogeneity.Conclusions—Despite doubling of the data since 1995, the magnitude of risks and benefits with rtPA remains imprecise. This gap in knowledge may be hindering clinical use of rtPA and can be filled only by new trials designed to address these specific issues.

ISSN:0039-2499    

出版商:OVID    

年代:2003

数据来源: OVID