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SummaryStroke is a leading cause of death and disability worldwide. Imaging plays a critical role in evaluating patients suspected of acute stroke and transient ischemic attack, especially before initiating treatment. Over the past few decades, major advances have occurred in stroke imaging and treatment, including Food and Drug Administration approval of recanalization therapies for the treatment of acute ischemic stroke. A wide variety of imaging techniques has become available to assess vascular lesions and brain tissue status in acute stroke patients. However, the practical challenge for physicians is to understand the multiple facets of these imaging techniques, including which imaging techniques to implement and how to optimally use them, given available resources at their local institution. Important considerations include constraints of time, cost, access to imaging modalities, preferences of treating physicians, availability of expertise, and availability of endovascular therapy. The choice of which imaging techniques to employ is impacted by both the time urgency for evaluation of patients and the complexity of the literature on acute stroke imaging. Ideally, imaging algorithms should incorporate techniques that provide optimal benefit for improved patient outcomes without delaying treatment.

Objective: Recanalization of arterial obstruction is associated with improved clinical outcomes. There are no controlled data demonstrating whether arterial obstruction status predicts the treatment effect of intravenous (IV) tissue plasminogen activator (tPA). We aimed to determine if the presence of arterial obstruction improves the treatment effect of IV tPA over placebo in attenuating infarct growth.Methods: We analyzed 175 ischemic stroke patients treated in the 3-6 hour time window from the Echoplanar Imaging Thrombolytic Evaluation Trial (EPITHET) trial (randomized to IV tPA or placebo) and Diffusion and perfusion imaging Evaluation For Understanding Stroke Evolution (DEFUSE) study (all treated with IV tPA). Infarct growth was calculated as the difference between baseline diffusion-weighted imaging (DWI) and final T2 lesion volumes. Baseline arterial obstruction of large intracranial arteries was graded on magnetic resonance angiography (MRA).Results: Among the 116 patients with adequate baseline MRA and final lesion assessment, 72 had arterial obstruction (48 tPA, 24 placebo) and 44 no arterial obstruction (33 tPA, 11 placebo). Infarct growth was lower in the tPA than placebo group (median difference 26ml, 95% confidence interval [CI], 1-50) in patients with arterial obstruction, but was similar in patients with no arterial obstruction (median difference 5ml, 95%CI, -3 to 9). Infarct growth attenuation with tPA over placebo treatment was greater among patients with arterial obstruction than those without arterial obstruction by a median of 32ml (95%CI, 21-43, p < 0.001).Interpretation: The treatment effect of IV tPA over placebo was greater with baseline arterial obstruction, supporting arterial obstruction status as a consideration in selecting patients more likely to benefit from IV thrombolysis. [ABSTRACT FROM AUTHOR]

Context: Tissue plasminogen activator is the only thrombolytic agent approved in the United States for treatment of acute ischemic stroke, and has limitations. Aptiganel hydrochloride is a novel and selective ligand for the ion-channel site of the N-methyl-D-aspartate receptor-channel complex and a promising neuroprotective agent in animal models of focal brain ischemia.Objective: To determine whether aptiganel improves the clinical outcome for acute ischemic stroke patients.Design: Nested phase 2/phase 3 randomized controlled trial conducted between July 1996 and September 1997.Setting: One hundred fifty-six medical centers in the United States, Canada, Australia, South Africa, England, and Scotland.Participants: A total of 628 patients with hemispheric ischemic stroke (50.3% male; mean age, 71.5 years).Interventions: Patients were randomly assigned within 6 hours of stroke to receive 1 of 3 treatment regimens: high-dose aptiganel (5-mg bolus followed by 0.75 mg/h for 12 hours; n = 214); low-dose aptiganel (3-mg bolus followed by 0.5 mg/h for 12 hours; n = 200); or placebo (n = 214).Main Outcome Measures: The primary efficacy end point was the Modified Rankin Scale score at 90 days after stroke onset. Secondary end points included mortality and change in National Institutes of Health (NIH) Stroke Scale score at 7 days after stroke.Results: The trial was suspended by the sponsor and the independent data and safety monitoring board because of both a lack of efficacy and a potential imbalance in mortality. There was no improvement in outcome for either aptiganel (low-dose or high-dose) group compared with the placebo group at 90 days (median Modified Rankin Scale score for all 3 treatment groups = 3; P =.31). At 7 days, placebo-treated patients exhibited slightly greater neurological improvement on the NIH Stroke Scale than high-dose aptiganel patients (mean improvement for placebo group, -0.8 points vs for high-dose aptiganel, 0.9 points; P =.04). The mortality rate at 120 days in patients treated with high-dose aptiganel was higher than that in patients who received placebo (26.3% vs 19.2%; P =.06). Mortality in the low-dose aptiganel group was 22.5% (P =.39 vs placebo).Conclusions: Aptiganel was not efficacious in patients with acute ischemic stroke at either of the tested doses, and m ay be harmful. The larger proportion of patients with favorable outcomes and lower mortality rate in the placebo group suggest that glutamate blockade with aptiganel may have detrimental effects in an undifferentiated population of stroke patients. [ABSTRACT FROM AUTHOR]

Context: Tissue-type plasminogen activator (tPA) is the only therapy for acute ischemic stroke approved by the Food and Drug Administration.Objective: To assess the safety profile and to document clinical outcomes and adverse events in patients treated with intravenous tPA for acute stroke in clinical practice.Design and Setting: Prospective, multicenter study of consecutive patients enrolled between February 1997 and December 1998 at 57 medical centers in the United States (24 academic and 33 community).Intervention: Intravenous tPA (recombinant alteplase).Patients: Three hundred eighty-nine patients with a mean age of 69 years (range, 28-100 years); 55% were men.Main Outcome Measures: Time intervals between stroke symptom onset, hospital arrival, and treatment with tPA; pretreatment computed tomographic scan results, intracerebral hemorrhage, and major systemic bleeding. The modified Rankin Scale score was used to assess clinical outcomes at 30 days.Results: Median time from stroke onset to treatment was 2 hours 44 minutes, and the median baseline National Institutes of Health Stroke Scale score was 13. The 30-day mortality rate was 13%. At 30 days after treatment, 35% of patients had very favorable outcomes (modified Rankin score, 0-1) and 43% were functionally independent (modified Rankin score, 0-2). Thirteen patients (3.3%) experienced symptomatic intracerebral hemorrhage, including 7 who died. Twenty-eight patients (8.2%) had asymptomatic intracerebral hemorrhage within 3 days of treatment with tPA. Protocol violations were reported for 127 patients (32.6%), and included treatment with tPA more than 3 hours after symptom onset in 13.4%, treatment with anticoagulants within 24 hours of tPA administration in 9.3%, and tPA administration despite systolic blood pressure exceeding 185 mm Hg in 6.7%. A multivariate analysis found predictors of favorable outcome to be a less severe baseline National Institutes of Health Stroke Scale score, absence of specific abnormalities (effacement or hypodensity of >33% of the middle cerebral artery territory or a hyperdense middle cerebral artery) on the baseline computed tomographic scan, an age of 85 years or younger, and a lower mean arterial pressure at baseline.Conclusions: This study, conducted at multiple institutions throughout the United States, suggests that favorable clinical outcomes and low rates of symptomatic intracerebral hemorrhage can be achieved using tPA for stroke treatment. [ABSTRACT FROM AUTHOR]

Objective: To examine the cost-effectiveness of prescribing warfarin sodium in patients who have nonvalvular atrial fibrillation (NVAF) with or without additional stroke risk factors (a prior stroke or transient ischemic attack, diabetes, hypertension, or heart disease).Design: Decision and cost-effectiveness analyses. The probabilities for stroke, hemorrhage, and death were obtained from published randomized controlled trials. The quality-of-life estimates were obtained by interviewing 74 patients with atrial fibrillation. Costs were estimated from literature review, phone survey, and Medicare reimbursement.Patients: In the base case, the patients were 65 years of age and good candidates for warfarin therapy.Interventions: Treatment with warfarin, aspirin, or no therapy in the decision analytic model.Main Outcome Measures: Quality-adjusted survival and marginal cost-effectiveness of warfarin as compared with aspirin or no therapy.Results: For patients with NVAF and additional risk factors for stroke, warfarin therapy led to a greater quality-adjusted survival and to cost savings. For patients with NVAF and one additional risk factor, warfarin therapy cost $8000 per quality-adjusted life-year saved. For 65-year-old patients with NVAF alone, warfarin cost about $370,000 per quality-adjusted life-year saved, as compared with aspirin therapy. However, for 75-year-old patients with NVAF alone, prescribing warfarin cost $110,000 per quality-adjusted life-year saved. For patients who were not prescribed warfarin, aspirin was preferred to no therapy on the basis of both quality-adjusted survival and cost in all patients, regardless of the number of risk factors present.Conclusions: Treatment with warfarin is cost-effective in patients with NVAF and one or more additional risk factors for stroke. In 65-year-old patients with NVAF but no other risk factors for stroke, prescribing warfarin instead of aspirin would affect quality-adjusted survival minimally but increase costs significantly. [ABSTRACT FROM AUTHOR]