Showing papers in "Stroke in 2013"

Guidelines for the Early Management of Patients With Acute Ischemic Stroke A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association

Abstract: Background and Purpose—The authors present an overview of the current evidence and management recommendations for evaluation and treatment of adults with acute ischemic stroke. The intended audienc...

An Updated Definition of Stroke for the 21st Century A Statement for Healthcare Professionals From the American Heart Association/American Stroke Association

Abstract: Despite the global impact and advances in understanding the pathophysiology of cerebrovascular diseases, the term "stroke" is not consistently defined in clinical practice, in clinical research, or in assessments of the public health. The classic definition is mainly clinical and does not account for advances in science and technology. The Stroke Council of the American Heart Association/American Stroke Association convened a writing group to develop an expert consensus document for an updated definition of stroke for the 21st century. Central nervous system infarction is defined as brain, spinal cord, or retinal cell death attributable to ischemia, based on neuropathological, neuroimaging, and/or clinical evidence of permanent injury. Central nervous system infarction occurs over a clinical spectrum: Ischemic stroke specifically refers to central nervous system infarction accompanied by overt symptoms, while silent infarction by definition causes no known symptoms. Stroke also broadly includes intracerebral hemorrhage and subarachnoid hemorrhage. The updated definition of stroke incorporates clinical and tissue criteria and can be incorporated into practice, research, and assessments of the public health.

Recommendations on Angiographic Revascularization Grading Standards for Acute Ischemic Stroke A Consensus Statement

Abstract: See related article, p 2509 Intra-arterial therapy (IAT) for acute ischemic stroke (AIS) has dramatically evolved during the past decade to include aspiration and stent-retriever devices. Recent randomized controlled trials have demonstrated the superior revascularization efficacy of stent-retrievers compared with the first-generation Merci device.1,2 Additionally, the Diffusion and Perfusion Imaging Evaluation for Understanding Stroke Evolution (DEFUSE) 2, the Mechanical Retrieval and Recanalization of Stroke Clots Using Embolectomy (MR RESCUE), and the Interventional Management of Stroke (IMS) III trials have confirmed the importance of early revascularization for achieving better clinical outcome.3–5 Despite these data, the current heterogeneity in cerebral angiographic revascularization grading (CARG) poses a major obstacle to further advances in stroke therapy. To date, several CARG scales have been used to measure the success of IAT.6–14 Even when the same scale is used in different studies, it is applied using varying operational criteria, which further confounds the interpretation of this key metric.10 The lack of a uniform grading approach limits comparison of revascularization rates across clinical trials and hinders the translation of promising, early phase angiographic results into proven, clinically effective treatments.6–14 For these reasons, it is critical that CARG scales be standardized and end points for successful revascularization be refined.6 This will lead to a greater understanding of the aspects of revascularization that are strongly predictive of clinical response. The optimal grading scale must demonstrate (1) a strong correlation with clinical outcome, (2) simplicity and feasibility of scale interpretation while ensuring characterization of relevant angiographic findings, and (3) high inter-rater reproducibility. To address these issues, a multidisciplinary panel of neurointerventionalists, neuroradiologists, and stroke neurologists with extensive experience in neuroimaging and IAT, convened at the “Consensus Meeting on Revascularization Grading Following Endovascular Therapy” with the goal …

Endovascular Treatment of Intracranial Aneurysms With Flow Diverters A Meta-Analysis

Abstract: Background and Purpose— Flow diverters are important tools in the treatment of intracranial aneurysms. However, their impact on aneurysmal occlusion rates, morbidity, mortality, and complication rates is not fully examined. Methods— We conducted a systematic review of the literature searching multiple databases for reports on the treatment of intracranial aneurysms with flow-diverter devices. Random effects meta-analysis was used to pool outcomes of aneurysmal occlusion rates at 6 months, and procedure-related morbidity, mortality, and complications across studies. Results— A total of 29 studies were included in this analysis, including 1451 patients with 1654 aneurysms. Aneurysmal complete occlusion rate was 76% (95% confidence interval [CI], 70%–81%). Procedure-related morbidity and mortality were 5% (95% CI, 4%–7%) and 4% (95% CI, 3%–6%), respectively. The rate of postoperative subarachnoid hemorrhage was 3% (95% CI, 2%–4%). Intraparenchymal hemorrhage rate was 3% (95% CI, 2%–4%). Perforator infarction rate was 3% (95% CI, 1%–5%), with significantly lower odds of perforator infarction among patients with anterior circulation aneurysms compared with those with posterior circulation aneurysms (odds ratio, 0.01; 95% CI, 0.00–0.08; P P Conclusions— This meta-analysis suggests that treatment of intracranial aneurysms with flow-diverter devices is feasible and effective with high complete occlusion rates. However, the risk of procedure-related morbidity and mortality is not negligible. Patients with posterior circulation aneurysms are at higher risk of ischemic stroke, particularly perforator infarction. These findings should be considered when considering the best therapeutic option for intracranial aneurysms.

Forecasting the Future of Stroke in the United States A Policy Statement From the American Heart Association and American Stroke Association

Abstract: Background and Purpose—Stroke is a leading cause of disability, cognitive impairment, and death in the United States and accounts for 1.7% of national health expenditures. Because the population is aging and the risk of stroke more than doubles for each successive decade after the age of 55 years, these costs are anticipated to rise dramatically. The objective of this report was to project future annual costs of care for stroke from 2012 to 2030 and discuss potential cost reduction strategies. Methods and Results—The American Heart Association/American Stroke Association developed methodology to project the future costs of stroke-related care. Estimates excluded costs associated with other cardiovascular diseases (hypertension, coronary heart disease, and congestive heart failure). By 2030, 3.88% of the US population >18 years of age is projected to have had a stroke. Between 2012 and 2030, real (2010$) total direct annual stroke-related medical costs are expected to increase from $71.55 billion to $184.1...

Carotid Plaque MRI and Stroke Risk A Systematic Review and Meta-analysis

Abstract: Background and Purpose— MRI characterization of carotid plaque has been studied recently as a potential tool to predict stroke caused by carotid atherosclerosis. We performed a systematic review and meta-analysis to summarize the association of MRI-determined intraplaque hemorrhage, lipid-rich necrotic core, and thinning/rupture of the fibrous cap with subsequent ischemic events. Methods— We performed a comprehensive literature search evaluating the association of carotid plaque composition on MRI with ischemic outcomes. We included cohort studies examining intraplaque hemorrhage, lipid-rich necrotic core, or thinning/rupture of the fibrous cap with mean follow-up of ≥1 month and an outcome measure of ipsilateral stroke or transient ischemic attack. A meta-analysis using a random-effects model with assessment of study heterogeneity and publication bias was performed. Results— Of the 3436 articles screened, 9 studies with a total of 779 subjects met eligibility for systematic review. The hazard ratios for intraplaque hemorrhage, lipid-rich necrotic core, and thinning/rupture of the fibrous cap as predictors of subsequent stroke/transient ischemic attack were 4.59 (95% confidence interval, 2.91–7.24), 3.00 (95% confidence interval, 1.51–5.95), and 5.93 (95% confidence interval, 2.65–13.20), respectively. No statistically significant heterogeneity or publication bias was present in the 3 main meta-analyses performed. Conclusions— The presence of intraplaque hemorrhage, lipid-rich necrotic core, and thinning/rupture of the fibrous cap on MRI of carotid plaque is associated with increased risk of future stroke or transient ischemic attack in patients with carotid atherosclerotic disease. Dedicated MRI of plaque composition offers stroke risk information beyond measurement of luminal stenosis in carotid atherosclerotic disease.

Natural History of Unruptured Intracranial Aneurysms A Long-term Follow-up Study

Abstract: Background and Purpose— Unruptured intracranial aneurysms are increasingly being detected and are a notable healthcare burden. We investigated the long-term natural history of unruptured intracranial aneurysms and risk factors predictive of subsequent rupture. Methods— A total of 142 patients with 181 unruptured intracranial aneurysms diagnosed between 1956 and 1978, when these were not treated, were followed up until death or subarachnoid hemorrhage, or until 2011 to 2012. Annual and cumulative incidences of aneurysm rupture and risk factors for rupture were studied using Kaplan–Meier survival analysis and Cox proportional hazards regression models. Results— The median follow-up time was 21.0 (range, 0.8–52.3) years. During 3064 person-years, there were 34 first episodes of aneurysm rupture, giving an average annual incidence of 1.1%. Eighteen patients died on account of an initial or recurrent aneurysm rupture. The cumulative rate of bleeding was 10.5% (95% confidence interval [CI], 5.2–15.8) at 10 years, 23.0% (95% CI, 15.4–30.6) at 20 years, and 30.1% (95% CI, 21.3–38.9) at 30 years. None of the index aneurysms bled after a follow-up of 25 years. Cigarette smoking (adjusted hazard ratio, 2.44; 95% CI, 1.02–5.88), location of the aneurysm in the anterior communicating artery (adjusted hazard ratio, 3.73; 95% CI, 1.23–11.36), patient age inversely (0.96 per year, 95% CI, 0.92–1.00) and aneurysm diameter ≥7 mm (adjusted hazard ratio, 2.60; 95% CI, 1.13–5.98) independently predicted subsequent aneurysm rupture, as did alcohol consumption (1.27 per 100 g/week; 95% CI, 1.05–1.53; P <0.05), but only in univariable analysis. Conclusions— Cigarette smoking, patient age inversely, and the size and location of the unruptured intracranial aneurysm seem to be risk factors for aneurysm rupture. The risk of bleeding decreases with a very long-term follow-up.

Review of Cerebral Aneurysm Formation, Growth, and Rupture

Abstract: Cerebral aneurysms (CAs) occur in 3% to 5% of the general population and are characterized by localized structural deterioration of the arterial wall, with loss of the internal elastic lamina and disruption of the media.1 The most dreaded complication of CAs is rupture, the likelihood of which is related to several modifiable and nonmodifiable risk factors. Despite advances in surgical techniques and perioperative management, the mortality and morbidity associated with aneurysm rupture remain high.2 Current therapeutic options are limited to invasive therapies, namely microsurgical clipping and endovascular treatment, both of which carry a non-negligible risk of procedural morbidity. In recent years, it has become obvious that CAs are not passively enlarging vascular structures but exhibit prominent features of inflammation and tissue degeneration. Other factors mainly hemodynamic, genetic, hormonal, and environmental may also play an important role. Knowledge of the pathogenic pathways of CAs may pave the way for the development of noninvasive therapies. The purpose of this review is to summarize the most relevant data on the molecular mechanisms, genetics, and risk factors for aneurysm formation, growth, and rupture. Although there are different forms of CAs, the present discussion focuses on saccular aneurysms, which represent the most common type of CAs and are also the most common cause of subarachnoid hemorrhage (SAH). ### Cerebral Aneurysms: an Inflammatory Disease Increasing evidence points to inflammation as the leading factor in the pathogenesis of CAs. The inflammatory process is initiated by a hemodynamic insult and leads to matrix metalloproteinases (MMPs)–mediated degradation of the extracellular matrix and apoptosis of smooth muscle cells (SMCs), which are the predominant matrix-synthesizing cells of the vascular wall. These processes act in concert to weaken the arterial wall progressively, resulting in dilatation, aneurysm formation, and ultimately rupture (Figure; Table 1). The data supporting a major role for inflammation in CA pathogenesis are …

Stent-Assisted Coiling of Intracranial Aneurysms: Predictors of Complications, Recanalization, and Outcome in 508 Cases

Abstract: Background and Purpose—Self-expanding stents are increasingly used for treatment of complex intracranial aneurysms. We assess the safety and the efficacy of intracranial stenting and determine predictors of treatment outcomes. Methods—A total of 508 patients with 552 aneurysms were treated with Neuroform and Enterprise stents between 2006 and 2011 at our institution. A multivariate analysis was conducted to identify predictors of complications, recanalization, and outcome. Results—Of 508 patients, 461 (91%) were treated electively and 47 (9%) in the setting of subarachnoid hemorrhage. Complications occurred in 6.8% of patients. In multivariate analysis, subarachnoid hemorrhage, delivery of coils before stent placement, and carotid terminus/middle cerebral artery aneurysm locations were independent predictors of procedural complications. Angiographic follow-up was available for 87% of patients at a mean of 26 months. The rates of recanalization and retreatment were, respectively, 12% and 6.4%. Older age, p...

Prevalence of Poststroke Cognitive Impairment South London Stroke Register 1995–2010

Abstract: Background and Purpose—Stroke is a common long-term condition with an increasing incidence as the population ages. This study evaluates temporal changes in the prevalence of cognitive impairment after first-ever stroke stratified by sociodemography, vascular risk factors, and stroke subtypes, up to 15 years after stroke. Methods—Data were collected between 1995 and 2010 (n=4212) from the community-based South London Stroke Register covering an inner-city multiethnic population of 271 817 inhabitants. Patients were assessed for cognitive function using Abbreviated Mental Test or Mini-Mental State Examination at the onset, 3 months, and annually thereafter. All estimates were age adjusted to the European standard. Results—The overall prevalence of cognitive impairment 3 months after stroke and at annual follow-up remained relatively unchanged at 22% (24% [95% CI, 21.2–27.8] at 3 months; 22% [17.4–26.8] at 5 years to 21% [3.6–63.8] at 14 years). In multivariate analyses, the poststroke prevalence ratio of co...

Dabigatran Versus Warfarin Effects on Ischemic and Hemorrhagic Strokes and Bleeding in Asians and Non-Asians With Atrial Fibrillation

Abstract: Background and Purpose-Intracranial hemorrhage rates are higher in Asians than non-Asians, especially in patients receiving warfarin. This randomized evaluation of long-term anticoagulation therapy subgroup analysis assessed dabigatran etexilate (DE) and warfarin effects on stroke and bleeding rates in patients from Asian and non-Asian countries. Methods-There were 2782 patients (15%) from 10 Asian countries and 15 331 patients from 34 non-Asian countries. A Cox regression model, with terms for treatment, region, and their interaction was used. Results-Rates of stroke or systemic embolism in Asians were 3.06% per year on warfarin, 2.50% per year on DE 110 mg BID (DE 110), and 1.39% per year on DE 150 mg BID (DE 150); in non-Asians, the rates were 1.48%, 1.37%, and 1.06% per year with no significant treatment-by-region interactions. Hemorrhagic stroke on warfarin occurred more often in Asians than non-Asians (hazard ratio [HR], 2.4; 95% confidence interval [CI], 1.3-4.7; P=0.007), with significant reductions for DE compared with warfarin in both Asian (DE 110 versus warfarin HR, 0.15; 95% CI, 0.03-0.66 and DE 150 versus warfarin HR, 0.22; 95% CI, 0.06-0.77) and non-Asian (DE 110 versus warfarin HR, 0.37; 95% CI, 0.19-0.72 and DE 150 versus warfarin HR, 0.28; 95% CI, 0.13-0.58) patients. Major bleeding rates in Asians were significantly lower on DE (both doses) than warfarin (warfarin 3.82% per year, DE 110 2.22% per year, and DE 150 2.17% per year). Conclusions-Hemorrhagic stroke rates were higher on warfarin in Asians versus non-Asians, despite similar blood pressure, younger age, and lower international normalized ratio values. Hemorrhagic strokes were significantly reduced by DE in both Asians and non-Asians. DE benefits were consistent across Asian and non-Asian subgroups.

Minimally Invasive Surgery Plus Recombinant Tissue-type Plasminogen Activator for Intracerebral Hemorrhage Evacuation Decreases Perihematomal Edema

Abstract: Background and Purpose—Perihematomal edema (PHE) can worsen outcomes after intracerebral hemorrhage (ICH). Reports suggest that blood degradation products lead to PHE. We hypothesized that hematoma evacuation will reduce PHE volume and that treatment with recombinant tissue-type plasminogen activator (rt-PA) will not exacerbate it. Methods—Minimally invasive surgery and rt-PA in ICH evacuation (MISTIE) phase II tested safety and efficacy of hematoma evacuation after ICH. We conducted a semiautomated, computerized volumetric analysis on computed tomography to assess impact of hematoma removal on PHE and effects of rt-PA on PHE. Volumetric analyses were performed on baseline stability and end of treatment scans. Results—Seventy-nine surgical and 39 medical patients from minimally invasive surgery and rt-PA in ICH evacuation phase II (MISTIE II) were analyzed. Mean hematoma volume at end of treatment was 19.6±14.5 cm3 for the surgical cohort and 40.7±13.9 cm3 for the medical cohort (P<0.001). Edema volume at...

Atrial Fibrillation, Stroke Risk, and Warfarin Therapy Revisited A Population-Based Study

Abstract: Background and Purpose— Atrial fibrillation (AF) is a major risk factor for ischemic stroke. This study aims to update the knowledge about AF and associated stroke risk and benefits of anticoagulation. Methods— We extracted data from the hospital, specialized outpatient, and primary healthcare and drug registries in a Swedish region with 1.56 million residents. We identified all individuals who had received an AF diagnosis during the previous 5 years; all stroke events during 2010; and patients with AF aged ≥50 years who had received warfarin during 2009. Results— AF had been diagnosed in 38 446 subjects who were alive at the beginning of 2010 (prevalence of 3.2% in the adult [≥20 years] population); ≈46% received warfarin therapy. In 2010, there were 4565 ischemic stroke events and 861 intracranial hemorrhages. AF had been diagnosed in 38% of ischemic events (≥50% among those aged ≥80 years) and in 23% of intracranial hemorrhages. An AF diagnosis was often lacking in hospital discharge records after stroke events. Warfarin therapy was associated with an odds ratio of 0.50 (confidence interval, 0.43–0.57) for ischemic stroke and, despite an increased risk of intracranial hemorrhage, an odds ratio of 0.57 (confidence interval, 0.50–0.64) for the overall risk for stroke. Conclusions— AF is more common than present guidelines suggest. The attributable risk of AF for ischemic stroke increases with age and is close to that of hypertension in individuals aged ≥80 years. Because a majority of patients with AF with increased risk for stroke had not received anticoagulation therapy, there is a large potential for improvement.

Is There a Cerebral Lymphatic System

Abstract: The brain is unique among virtually all somatic organs in its lack of a conventional lymphatic vasculature.1–3 In the periphery, the lymphatic circulation facilitates the clearance of extracellular proteins and excess fluid from the interstitium, a role critical to tissue homeostasis and function.4,5 Yet within the brain, despite its complex architecture and high metabolic activity and neural cells’ sensitivity to changes in the extracellular environment, no specialized organ-wide anatomic structure has yet been identified that facilitates the efficient lymphatic clearance of extracellular solutes and fluid from the brain parenchyma. For small molecules and hydrophobic compounds, efflux across the blood–brain barrier is relatively unrestricted. Molecules that are substrates for specific blood–brain barrier transporters are also readily cleared from the brain.6,7 Other compounds must be cleared from the brain interstitium to the cerebrospinal fluid (CSF) compartment, where they are ultimately eliminated to the blood stream via arachnoid granulations or to peripheral lymphatics along cranial nerves.1,8,9 However, the distances between much of the brain tissue and the CSF compartments are too great for efficient clearance by simple diffusion, particularly for large molecules (such as peptides and proteins) with low diffusion coefficients.6 Rather, the clearance of these interstitial solutes from the brain is attributed to bulk flow, by which convective currents of interstitial fluid (ISF) sweep solutes along at a high rate that is largely independent of molecular size.1,2,6,7 In a controversial series of studies, Grady et al10,11 suggested that brain ISF may exchange with CSF along paravascular routes surrounding cerebral blood vessels. Because these findings seemed to be subsequently refuted by Cserr et al,12,13 such retrograde movement of CSF into the brain parenchyma is now thought to …

National Institutes of Health Stroke Scale Score and Vessel Occlusion in 2152 Patients With Acute Ischemic Stroke

Abstract: Background and Purpose— There is some controversy on the association of the National Institutes of Health Stroke Scale (NIHSS) score to predict arterial occlusion on MR arteriography and CT arteriography in acute stroke. Methods— We analyzed NIHSS scores and arteriographic findings in 2152 patients (35.4% women, mean age 66±14 years) with acute anterior or posterior circulation strokes. Results— The study included 1603 patients examined with MR arteriography and 549 with CT arteriography. Of those, 1043 patients (48.5%; median NIHSS score 5, median time to clinical assessment 179 minutes) showed an occlusion, 887 in the anterior (median NIHSS score 7/0–31), and 156 in the posterior circulation (median NIHSS score 3/0–32). Eight hundred sixty visualized occlusions (82.5%) were located centrally (ie, in the basilar, intracranial vertebral, internal carotid artery, or M1/M2 segment of the middle cerebral artery). NIHSS scores turned out to be predictive for any vessel occlusions in the anterior circulation. Best cut-off values within 3 hours after symptom onset were NIHSS scores ≥9 (positive predictive value 86.4%) and NIHSS scores ≥7 within >3 to 6 hours (positive predictive value 84.4%). Patients with central occlusions presenting within 3 hours had NIHSS scores Conclusions— There is a significant association of NIHSS scores and vessel occlusions in patients with anterior circulation strokes. This association is best within the first hours after symptom onset. Thereafter and in the posterior circulation the association is poor.

Cholesterol Levels and Risk of Hemorrhagic Stroke A Systematic Review and Meta-Analysis

Abstract: Background and Purpose—Cholesterol levels are inconsistently associated with the risk of hemorrhagic stroke. The purpose of this study is to assess their relationships using a meta-analytic approach. Methods—We searched PubMed and Embase for pertinent articles published in English. Only prospective studies that reported effect estimates with 95% confidential intervals (CIs) of hemorrhagic stroke for ≥3 categories of cholesterol levels, for high and low comparison, or for per 1 mmol/L increment of cholesterol concentrations were included. We used the random-effects model to pool the study-specific results. Results—Twenty-three prospective studies were included, totaling 1 430 141 participants with 7960 (5.6%) hemorrhagic strokes. In high versus low analysis, the summary relative risk of hemorrhagic stroke was 0.69 (95% CI, 0.59–0.81) for total cholesterol, 0.98 (95% CI, 0.80–1.19) for high-density lipoprotein cholesterol, and 0.62 (95% CI, 0.41–0.92) for low-density lipoprotein cholesterol. In dose–respons...

N2 Neutrophils, Novel Players in Brain Inflammation After Stroke Modulation by the PPARγ Agonist Rosiglitazone

Abstract: Background and Purpose—Neutrophils have been traditionally recognized as major mediators of a deleterious inflammatory response in acute ischemic stroke, but their potential as a therapeutic target remains unexplored. Recent evidence indicates that neutrophils may acquire different phenotypes and contribute to resolution of inflammation through the release of anti-inflammatory mediators. Thus, similar to M2 macrophages, neutrophils have been proposed to shift toward an N2 phenotype, a polarization that is peroxisome proliferator-activated receptor-γ dependent in macrophages. We hypothesize that peroxisome proliferator-activated receptor-γ activation with rosiglitazone induces changes in neutrophilic mobilization and phenotype that might influence stroke outcome. Methods—Brain sections and cell suspensions were prepared from mice exposed to permanent distal middle cerebral artery occlusion. Double immunostaining with stereological counting of brain sections and flow-cytometry analysis of brain cell suspens...

Cost-Effectiveness of Apixaban, Dabigatran, Rivaroxaban, and Warfarin for Stroke Prevention in Atrial Fibrillation

Abstract: Background and Purpose—To estimate the cost-effectiveness of stroke prevention in patients with nonvalvular atrial fibrillation by using novel oral anticoagulants apixaban 5 mg, dabigatran 150 mg, and rivaroxaban 20 mg compared with warfarin. Methods—A Markov decision-analysis model was constructed using data from clinical trials to evaluate lifetime costs and quality-adjusted life-years of novel oral anticoagulants compared with warfarin. The modeled population was a hypothetical cohort of 70-year-old patients with nonvalvular atrial fibrillation, increased risk for stroke (CHADS2 ≥1), renal creatinine clearance ≥50 mL/min, and no previous contraindications to anticoagulation. The willingness-to-pay threshold was $50 000/quality-adjusted life-years gained. Results—In the base case, warfarin had the lowest cost of $77 813 (SD, $2223), followed by rivaroxaban 20 mg ($78 738±$1852), dabigatran 150 mg ($82 719±$1959), and apixaban 5 mg ($85 326±$1512). Apixaban 5 mg had the highest quality-adjusted life-year...

Prospective, Multicenter, Single-Arm Study of Mechanical Thrombectomy Using Solitaire Flow Restoration in Acute Ischemic Stroke

Abstract: Background and Purpose—Mechanical thrombectomy using stent retriever devices have been advocated to increase revascularization in intracranial vessel occlusion. We present the results of a large prospective study on the use of the Solitaire Flow Restoration in patients with acute ischemic stroke. Methods—Solitaire Flow Restoration Thrombectomy for Acute Revascularization was an international, multicenter, prospective, single-arm study of Solitaire Flow Restoration thrombectomy in patients with large vessel anterior circulation strokes treated within 8 hours of symptom onset. Strict criteria for site selection were applied. The primary end point was the revascularization rate (thrombolysis in cerebral infarction ≥2b) of the occluded vessel as determined by an independent core laboratory. The secondary end point was the rate of good functional outcome (defined as 90-day modified Rankin scale, 0–2). Results—A total of 202 patients were enrolled across 14 comprehensive stroke centers in Europe, Canada, and Au...

The Evolution of Technology

Abstract: The historical development of technologies for catheter-based reperfusion of the acutely ischemic human brain is brief but eventful (Table). The first clinical patients were treated with local microcatheter delivery of intra-arterial fibrinolytics in the mid-1990s. The first mechanical recanalization technique, primary intra-arterial balloon angioplasty, was described a few years later. Over the subsequent decade and a half, successive waves of innovative mechanical thrombectomy devices were introduced. The rapid proliferation of technology reflects the inherent dynamic of biomechanical device development, characterized by rapid engineering innovation focused on a well-circumscribed target, in contrast to the slower, more deliberate arc of drug development, which requires extensive testing of each new molecular entity for unexpected off-target effects on diverse organs. The heterogeneity of target vascular lesions in cerebrovascular disease mandates a diversity of mechanical treatment options for deployment by interventionalists. In many patients, the intracranial occlusion is an embolus that has arisen from the heart or a proximal aortocervical arterial source and landed in a relatively normal recipient artery. Such target thrombi respond well to retrieval and aspiration strategies. In other patients, the occlusive lesion is comprised of an in situ intracranial atherosclerotic plaque with supervening thrombosis. These target lesions will not respond well to retrieval devices, which catch on the plaque, or to aspiration devices, which are effective only for the thrombus component. However, they do respond well to angioplasty and stenting, which accomplish controlled cracking and dissection of the underlying atherosclerotic lesions.1 There is a notable race, ethnic variation in the composition of intracranial occlusions.2 Among whites, emboli from the heart or extracranial arterial sources are common; among Asians and blacks, in situ intracranial atherosclerosis with supervening thrombosis is more frequent. As a result, the most effective and commonly used mechanical treatment strategies vary regionally across the globe. The endovascular …

Endovascular treatment of intracranial aneurysms: current status.

Abstract: In a recent systematic review and meta-analysis, the overall prevalence of unruptured intracranial aneurysms (IAs) is estimated as 3.2%.1 The prevalence of IAs is higher in patients with autosomal dominant polycystic kidney disease or a positive family history of IAs of subarachnoid hemorrhage (SAH).1 From the same review, the size of unruptured IAs is <5 mm in 66%, 5 to 9 mm in 27%, and ≥10 mm in 7%; the site of IAs is internal carotid artery, including posterior communicating artery in 42%, middle cerebral artery in 35%, and anterior cerebral artery and anterior communicating artery in 18%. Most IAs are clinically silent until rupture, which is unpredictable and sometimes associated with SAH, intraparenchymal hematoma, and an intraventricular hemorrhage. The case fatality of IA rupture is high (from 27% to 44%), but has decreased during the past 3 decades because of the introduction of improved management strategies, including neurocritical care.2 The International Study of Unruptured Intracranial Aneurysms (ISUIA) showed an increased risk of IA rupture with aneurysm size and for posterior circulation aneurysms.3 Although treatment of a ruptured aneurysm is accepted as an emergency, indication for treatment of unruptured IAs is still being discussed. Decision for treatment is based on clinical and anatomic factors; among them, the most important being patient’s age, family history of IA(s), associated conditions (autosomal dominant polycystic kidney disease), symptomatic aneurysms, aneurysm size, and location. The randomized International Subarachnoid Aneurysm Trial (ISAT) study has clearly demonstrated the superiority of endovascular treatment (EVT) of ruptured aneurysms using coil technology over surgery.4 Since the publication of these results, EVT has rapidly evolved. Although for unruptured aneurysms a direct comparison between EVT and surgery is not available, EVT has been widely used in this subgroup as well.5 In fact the population presenting with …

Clipping Versus Coiling for Ruptured Intracranial Aneurysms A Systematic Review and Meta-Analysis

Abstract: Background and Purpose—Endovascular treatment has increasingly been used for aneurismal subarachnoid aneurismal hemorrhage. The aim of this analysis is to assess the current evidence regarding safety and efficiency of clipping compared with coiling. Methods—We conducted a meta-analysis of studies that compared clipping with coiling between January 1999 and July 2012. Comparison of binary outcomes between treatment groups was described using odds ratios (OR; clip versus coil). Results—Four randomized controlled trials and 23 observational studies were included. Randomized controlled trials showed that coiling reduced the 1-year unfavorable outcome rate (OR, 1.48; 95% confidence interval [CI], 1.24–1.76). However, there was no statistical deference in nonrandomized controlled trials (OR, 1.11; 95% CI, 0.96–1.28). Subgroup analysis revealed coiling yielded better outcomes for patients with good preoperative grade (OR, 1.51; 95% CI, 1.24–1.84) than for poor preoperative patients (OR, 0.88; 95% CI 0.56–1.38). ...

Telephone Assessment of Cognition After Transient Ischemic Attack and Stroke: Modified Telephone Interview of Cognitive Status and Telephone Montreal Cognitive Assessment Versus Face-to-Face Montreal Cognitive Assessment and Neuropsychological Battery

Abstract: Background and Purpose—Face-to-face cognitive testing is not always possible in large studies. Therefore, we assessed the telephone Montreal Cognitive Assessment (T-MoCA: MoCA items not requiring p...

Life’s Simple 7 and Risk of Incident Stroke The Reasons for Geographic and Racial Differences in Stroke Study

Abstract: Background and Purpose—The American Heart Association developed Life’s Simple 7 (LS7) as a metric defining cardiovascular health. We investigated the association between LS7 and incident stroke in black and white Americans. Methods—The Reasons for Geographic And Racial Differences in Stroke (REGARDS) is a national population-based cohort of 30 239 blacks and whites, aged ≥45 years, sampled from the US population from 2003 to 2007. Data were collected by telephone, self-administered questionnaires, and an in-home examination. Incident strokes were identified through biannual participant contact followed by adjudication of medical records. Levels of the LS7 components (blood pressure, cholesterol, glucose, body mass index, smoking, physical activity, and diet) were each coded as poor (0 point), intermediate (1 point), or ideal (2 points) health. An overall LS7 score was categorized as inadequate (0–4), average (5–9), or optimum (10–14) cardiovascular health. Results—Among 22 914 subjects with LS7 data and n...

Susceptibility-Weighted Imaging is More Reliable Than T2*-Weighted Gradient-Recalled Echo MRI for Detecting Microbleeds

Abstract: Background and Purpose—We investigated the sensitivity and reliability of MRI susceptibility-weighted imaging (SWI) compared with routine MRI T2*-weighted gradient-recalled echo (GRE) for cerebral microbleed (CMB) detection. Methods—We used data from a prospective study of cerebral amyloid angiopathy (n=9; mean age, 71±8.3) and healthy non–cerebral amyloid angiopathy controls (n=22; mean age, 68±6.3). Three raters (labeled 1, 2, and 3) independently interpreted the GRE and SWI sequences (using the phase-filtered magnitude image) blinded to clinical information. Results—In 9 cerebral amyloid angiopathy cases, the raters identified 1146 total CMBs on GRE and 1432 CMBs on SWI. In 22 healthy control subjects, the raters identified ≥1 CMBs in 6/22 on GRE (total 9 CMBs) and 5/22 on SWI (total 19 CMBs). Among cerebral amyloid angiopathy cases, the reliability between raters for CMB counts was good for SWI (intraclass correlation coefficient, 0.87) but only moderate for GRE (intraclass correlation coefficient, 0....

Changes in Normal-Appearing White Matter Precede Development of White Matter Lesions

Abstract: Background and Purpose— It is unknown whether white matter lesions (WML) develop abruptly in previously normal brain areas, or whether tissue changes are already present before WML become apparent on MRI. We therefore investigated whether development of WML is preceded by quantifiable changes in normal-appearing white matter (NAWM). Methods— In 689 participants from the general population (mean age 67 years), we performed 2 MRI scans (including diffusion tensor imaging and Fluid Attenuation Inversion Recovery [FLAIR] sequences) 3.5 years apart using the same 1.5-T scanner. Using automated tissue segmentation, we identified NAWM at baseline. We assessed which NAWM regions converted into WML during follow-up and differentiated new WML into regions of WML growth and de novo WML. Fractional anisotropy, mean diffusivity, and FLAIR intensity of regions converting to WML and regions of persistent NAWM were compared using 3 approaches: a whole-brain analysis, a regionally matched approach, and a voxel-wise approach. Results— All 3 approaches showed that low fractional anisotropy, high mean diffusivity, and relatively high FLAIR intensity at baseline were associated with WML development during follow-up. Compared with persistent NAWM regions, NAWM regions converting to WML had significantly lower fractional anisotropy (0.337 vs 0.387; P <0.001), higher mean diffusivity (0.910×10–3 mm2/s vs 0.729×10–3 mm2/s; P <0.001), and relatively higher normalized FLAIR intensity (1.233 vs –0.340; P <0.001). This applied to both NAWM developing into growing and de novo WML. Conclusions— White matter changes in NAWM are present and can be quantified on diffusion tensor imaging and FLAIR before WML develop. This suggests that WML develop gradually, and that visually appreciable WML are only the tip of the iceberg of white matter pathology.

Reliability (Inter-rater Agreement) of the Barthel Index for Assessment of Stroke Survivors Systematic Review and Meta-analysis

Abstract: Background and Purpose—The Barthel Index (BI) is a 10-item measure of activities of daily living which is frequently used in clinical practice and as a trial outcome measure in stroke. We sought to describe the reliability (interobserver variability) of standard BI in stroke cohorts using systematic review and meta-analysis of published studies. Methods—Two assessors independently searched various multidisciplinary electronic databases from inception to April 2012 inclusive. Inclusion criteria comprised: original research, human stroke participants, and inter-rater reliability data on equivalent methods of BI administration. Manuscripts were reviewed against prespecified inclusion criteria. Primary outcome for meta-analysis was reliability, measured by weighted κ (κw). Results—From 20 210 titles, 306 abstracts were reviewed, 12 studies met inclusion criteria, and 10 were included in meta-analysis (n=543 participants; range of participants in studies, 7–21). There was substantial clinical heterogeneity wit...

Silent Information Regulator 1 Protects the Brain Against Cerebral Ischemic Damage

Abstract: Background and Purpose—Sirtuin 1 (SIRT1) is a member of NAD+-dependent protein deacetylases implicated in a wide range of cellular functions and has beneficial properties in pathologies including ischemia/reperfusion processes and neurodegeneration. However, no direct evidence has been reported on the direct implication of SIRT1 in ischemic stroke. The aim of this study was to establish the role of SIRT1 in stroke using an experimental model in mice. Methods—Wild-type and Sirt1−/− mice were subjected to permanent focal ischemia by permanent ligature. In another set of experiments, wild-type mice were treated intraperitoneally with vehicle, activator 3 (SIRT1 activator, 10 mg/kg), or sirtinol (SIRT1 inhibitor, 10 mg/kg) for 10 minutes, 24 hours, and 40 hours after ischemia. Brains were removed 48 hours after ischemia for determining the infarct volume. Neurological outcome was evaluated using the modified neurological severity score. Results—Exposure to middle cerebral artery occlusion increased SIRT1 expr...

Near-infrared Spectroscopy–mediated Neurofeedback Enhances Efficacy of Motor Imagery–based Training in Poststroke Victims A Pilot Study

Abstract: Background and Purpose—Despite the findings that motor imagery and execution are supposed to share common neural networks, previous studies using imagery-based rehabilitation have revealed inconsistent results. In the present study, we investigated whether feedback of cortical activities (neurofeedback) using near-infrared spectroscopy could enhance the efficacy of imagery-based rehabilitation in stroke patients. Methods—Twenty hemiplegic patients with subcortical stroke received 6 sessions of mental practice with motor imagery of the distal upper limb in addition to standard rehabilitation. Subjects were randomly allocated to REAL and SHAM groups. In the REAL group, cortical hemoglobin signals detected by near-infrared spectroscopy were fed back during imagery. In the SHAM group, irrelevant randomized signals were fed back. Upper limb function was assessed using the finger and arm subscales of the Fugl-Meyer assessment and the Action Research Arm Test. Results—The hand/finger subscale of the Fugl-Meyer a...

Statin Therapy and Outcome After Ischemic Stroke: Systematic Review and Meta-Analysis of Observational Studies and Randomized Trials

Abstract: Background and Purpose-Although experimental data suggest that statin therapy may improve neurological outcome after acute cerebral ischemia, the results from clinical studies are conflicting. We p ...