Functional Outcome In Acute Stroke Research Articles

Abstract WMP69: Brain Atrophy and White Matter Disease Agreement on NCCT and MRI in Ischemic Stroke

Background: NCCT is the most widely used parenchymal imaging for acute stroke. Evaluations of brain frailty measures like atrophy and white matter disease (WMD) are becoming increasingly relevant in stroke outcome prediction but are conventionally thought to be best seen on MRI. We assessed the agreement between baseline NCCT and follow-up MRI ratings of brain atrophy and WMD and compared their predictive validity in relation to 90-day functional outcomes in acute ischemic stroke. Methods: In this post-hoc analysis of baseline NCCT and follow-up MRI data from the Alteplase compared to Tenecteplase (AcT) randomised-controlled trial, expert readers (stroke neurologists and radiologists) assessed atrophy using the global cortical atrophy (GCA), Koedam, and medial temporal lobe atrophy scales. WMD was measured using the Fazekas scale. Binary agreement (none-mild vs. moderate-severe) and agreement across the full range of scores between atrophy and WMD measures on NCCT and MRI were calculated using Gwet’s agreement coefficient (AC1). Logistic regressions and Delong’s test were used to compare the area under the curve (AUC) for the prediction of 90-day modified Rankin score (mRS) 0-1 when using NCCT vs MRI-based ratings for each atrophy and WMD variable. Results: Of 1577 patients included in the AcT trial, 491 had interpretable NCCT+MRI. Binary agreement was substantial (AC1:0.68-0.80) for deep and total WMD scores, Koedam scale and frontal GCA. Almost perfect binary agreement (AC1:0.81-0.97) was found for all other measures. Deep white matter showed a significant difference between NCCT and MRI ratings for predicting 90-day mRS 0-1 (MRI AUC = 0.61 [0.56-0.66], CT AUC = 0.56 [0.50-0.60], p = 0.01, Delong p = 0.02) There was no significant difference in predicting 90-day mRS for the other variables (all p > 0.12, GCA: MRI AUC = 0.54 [0.49-0.60] CT AUC = 0.53 [0.47-0.58], p = 0.58, Delong p = 0.86). Conclusion: NCCT ratings of brain atrophy and WMD by experts have substantial to almost-perfect agreement with MRI atrophy and WMD ratings and achieve similar prediction of 90-day mRS 0-1 functional outcomes in acute stroke patients. This implies that it is reasonable to use NCCT scans to evaluate these brain frailty measures in clinical practice and in stroke trials.

Effect of Endurance Training on Long-Term Stroke Survivors

Background: Stroke is one of the leading causes of dependency and mortality in India. Chronic stroke is defined as 6 months to years from the time of onset. Structural impairment which occurs in stroke lead to the complex nature of functional limitations. High blood pressure, diabetes mellitus, blood vessel diseases, and obesity are a few risk factors that can cause stroke. Once the patient goes into the chronic phase, a wide range of problems in functional mobility, gait, and Quality of Life may occur. Majority of times the patient survives their remaining life with these disabilities. The survival rate decreases with an increase in time. Only 1% survive 20 years after stroke. Physiotherapy has shown a positive effect on functional outcomes in acute stroke. Its efficacy should be tried on chronic survivors. Method: 36 subjects were included as per the inclusion and exclusion criteria. The treatment protocol was given for 42 days. Pre and post-changes in subjects were analyzed on a modified Barthel index and stroke-specific Quality of Life scale. Result: Data was analyzed using the student’s t-test. Findings showed significant change in outcome measures interns of mobility and quality. Conclusion: Endurance training improves functional mobility and standard of living in chronic stroke survivors.

Fluid-Attenuated Inversion Recovery Vascular Hyperintensity as a Potential Predictor for the Prognosis of Acute Stroke Patients After Intravenous Thrombolysis.

BackgroundFluid-attenuated inversion recovery vascular hyperintensity (FVH) can reflect the collateral status, which may be a valuable indicator to predict the functional outcome of acute stroke (AS) patients.MethodsA total of 190 AS patients with large vessel occlusion (LVO) were retrospectively investigated. All patients completed a 6-month follow-up and their modified Rankin Scale (mRS) scores were recorded at 1, 3, and 6 months after intravenous thrombolysis (IVT). Based on their mRS at 3 months, patients were divided into two groups: poor prognosis (131 patients; 68.9% of all subjects) and favorable prognosis (59 patients; 31.1% of all subjects). The death records of 28 patients were also analyzed in the poor prognosis group.Results(1) Univariate and multivariate analyses showed that the higher National Institutes of Health Stroke Scale (NIHSS) score at admission, higher fasting blood glucose, and lower FVH score were independent risk factors to predict the poor prognosis of IVT. (2) Survival analysis indicated that FVH score was the only baseline factor to predict the 6-month survival after IVT. (3) Baseline FVH score had great prediction performance for the prognosis of IVT (area under the curve = 0.853). (4) Baseline FVH score were negatively correlated with the NIHSS score at discharge and mRS score at 1, 3, and 6 months.ConclusionAmong various baseline clinical factors, only the FVH score might have implications for 3-month outcome and 6-month survival of AS patients after IVT. Baseline FVH score showed great potential to predict the prognosis of the AS patients.

Direct Transfer to Angiosuite in Acute Stroke

Time to reperfusion is one of the strongest predictors of functional outcome in acute stroke due to a large vessel occlusion (LVO). Direct transfer to angiography suite (DTAS) protocols have shown encouraging results in reducing in-hospital delays. DTAS allows bypassing of conventional imaging in the emergency room by ruling out an intracranial hemorrhage or a large established infarct with imaging performed before transfer to the thrombectomy-capable center in the angiography suite using flat-panel CT (FP-CT). The rate of patients with stroke code primarily admitted to a comprehensive stroke center with a large ischemic established lesion is <10% within 6 hours from onset and remains <20% among patients with LVO or transferred from a primary stroke center. At the same time, stroke severity is an acceptable predictor of LVO. Therefore, ideal DTAS candidates are patients admitted in the early window with severe symptoms. The main difference between protocols adopted in different centers is the inclusion of FP-CT angiography to confirm an LVO before femoral puncture. While some centers advocate for FP-CT angiography, others favor additional time saving by directly assessing the presence of LVO with an angiogram. The latter, however, leads to unnecessary arterial punctures in patients with no LVO (3%–22% depending on selection criteria). Independently of these different imaging protocols, DTAS has been shown to be effective and safe in improving in-hospital workflow, achieving a reduction of door-to-puncture time as low as 16 minutes without safety concerns. The impact of DTAS on long-term functional outcomes varies between published studies, and randomized controlled trials are warranted to examine the benefit of DTAS.

Coexisting of aortic arch atheroma and atrial fibrillation for short-term recurrence and poor functional outcome in acute stroke.

Multiple embolic sources are sometimes observed simultaneously in patients with embolic stroke. The present study investigated the effects of coexisting aortic arch atheroma ≥ 4mm thick and atrial fibrillation (AF) on short-term stroke recurrence and functional outcome. Transesophageal echocardiography (TEE) was performed in consecutive embolic stroke patients, and 395 patients were classified into 4 groups according to the presence of aortic arch atheroma ≥ 4mm thick and AF: AF - /ARCH - group, AF + /ARCH - group, AF - /ARCH + group, and AF + /ARCH + group. In accordance with these 4 groups, we evaluated stroke recurrence and all-cause death for 3months after stroke onset, and also evaluated the 3-month functional outcome using the modified Rankin scale (mRS). Among the 128 AF patients, 39.1% also had aortic arch atheroma ≥ 4mm thick. Of the 395 enrolled cases, the AF + /ARCH + group showed the highest frequencies of stroke recurrence and all-cause death during 3months after onset. On multivariate analysis, stroke recurrence or all-cause death during 3months after onset was relatively more frequent in the AF + /ARCH + group than in the AF + /ARCH - group (OR, 2.34; 95% CI, 0.82-6.69; p = 0.11), but that was not statistically significant, and poor functional outcome (mRS score 3-6) at 3months was significantly more frequent in the AF + /ARCH + group than in the AF + /ARCH - group (OR, 2.59; 95% CI, 1.08-6.24; p = 0.0339). Aortic arch atheroma concomitant with AF is not rare and appears associated with increased risks of stroke recurrence and poor functional outcome.

Liver Function, Leucocyte, and Blood Pressure Levels with Acute Stroke Functional Outcomes

Several studies have shown that there is an increase in bilirubin levels, leukocytes, and blood pressure in acute phase strokes. The purpose of this study was to determine the relationship between liver function levels, leucocytes, and blood pressure with the functional outcome of acute stroke. The method was a cross-sectional study with a sample size of 30 people who were selected by consecutive non-random sampling method, clinically proven acute stroke patients, and computed tomography (CT) scan. They were studied at the General Hospital of the Adam Malik Center. Demographic data were analyzed using descriptive statistics. The results showed that all subjects did not differ in terms of demographic characteristics. This study concluds that there is no relation between liver function (total bilirubin, direct bilirubin, indirect bilirubin, serum glutamic oxaloacetic transaminase [AST], serum glutamic pyruvic transaminase [SGPT], alkaline phosphatase [ALP]), leukocytes, and blood pressure with acute stroke functional outcome. The functional outcome in acute hemorrhagic stroke is worse than acute ischemic stroke. Higher levels of liver function, leucocytes, and blood pressure were found in patients with the worse functional outcome though not significantly associated.

Abstract P659: Pre-Stroke Chads 2 Scores Should Be Associated With Onset Severity and Functional Outcome in Acute Stroke Patients With Atrial Fibrillation During Oral Anticoagulants: A Sub-Analysis of PASTA Registry Study

Background and Purpose: The impact of CHADS 2 score on neurological severity in patients with stroke during oral anticoagulant (OAC) has not yet been elucidated. We investigated the association between pre-stroke CHADS 2 score and severity on admission and functional outcome in acute cardioembolic stroke due to AF during OAC. Methods: We conducted an investigator-initiated, multicenter, prospective, observational cohort study, PASTA registry. One thousand forty-three patients with transient ischemic attack, ischemic stroke, and ICH who were taking OACs were prospectively enrolled in 25 medical institutions throughout Japan. We compared the clinical characteristics including severity onset and discharge outcome between low CHADS 2 score group (<2), and high CHADS 2 score group (≥2) in patients with cardioembolic stroke due to AF. Result: A total of 548 patients (237 women; median age 80 [quartiles 74-85] years) were enrolled. Of these, there were 76 patients (14%) in low CHADS 2 group and 472 (86%) in high CHADS 2 score group (Fig A). Along with increase of pre-stroke CHADS 2 score, NIHSS score was gradually increased (Fig B). Low CHADS 2 score group was associate with good outcome than high CHADS 2 group (p<0.001, Fig C). Age (p<0.001), male (p<0.001), pre-stroke CHADS 2 score (p<0.001), and initial NIHSS score (p<0.001) were significantly higher in non-excellent outcome (mRS≥2) group than excellent outcome group (mRS<2). In contrast, creatinine clearance and body weight were higher in excellent outcome group (Both p<0.001). Multivariate logistic regression analysis indicated that high pre-stroke CHADS 2 score independently associated with higher NIHSS score (NIHSS score≥6; OR 1.55, 95%CI 1.02-2.36, p=0.041) and non-excellent outcome (OR 1.94, 95%CI 1.01-3.80, p=0.047). Conclusion: The present study suggests that the pre-stroke CHADS 2 score should be useful for the prediction of clinical outcomes in patients with cardioembolic stroke due to AF even taking OAC.

Abstract TP261: Red Blood Cell Distribution Width is Associated With Collateral Flow and Infarct Volume Growth in Acute Stroke With Large Artery Atherosclerosis

Background and Purpose: Red cell distribution width (RDW) has been recognized as a prognostic marker in cardiovascular diseases and stroke. Increased RDW is predictive of poor outcome and mortality in acute ischemic stroke patients. However, the underlying mechanisms are not fully understood. We aimed to explore the association between RDW, collateral flow, infarct volume growth, final infarct volume (FIV), and clinical outcomes in acute stroke patients with large artery atherosclerosis. Methods: This is a single-center retrospective cohort study based on a prospective registry of consecutive acute ischemic stroke patients within 6 hours of onset. Acute ischemic stroke identified with anterior circulation large artery atherosclerosis (LAA) with complete baseline and follow-up imaging (Non-contrast CT, CT Angiography, Perfusion CT) as well as clinical profiles were enrolled. Collaterals was assessed using the volume ratio between delay time (DT) >3s and DT>6s lesions. Baseline infarct core volume was defined by relative cerebral blood flow<30%. FIV was calculated by manually drawing regions of interest on the follow-up images. Infarct volume growth was determined from FIV minus baseline infarct core volume. A good functional outcome was defined as a 3-month modified Rankin Score of 0-2. The relationship between RDW, collaterals, infarct volume growth, FIV and clinical outcomes were evaluated using multivariate models. Results: A total number of 100 patients were included in this study. Multivariate adjusted general linear models revealed that increased RDW was associated with poorer collaterals (multivariate adjusted coefficient -0.11, 95% CI -0.20 — -0.02, p=0.02) and increased infarct volume growth (multivariate adjusted coefficient 0.06, 95% CI 0.03 — 0.08, p<0.001). No significant relationship was found between RDW and FIV (multivariate adjusted coefficient 0.08, 95% CI -0.01 — 0.13, p=0.08), RDW and clinical outcomes (multivariate adjusted OR 1.66, 95% CI 0.44 — 6.28, p=0.46) probably due to the small sample size. Conclusion: For patients with LAA stroke, high RDW was associated with poorer collateral flow and increased infarct volume growth, which may explain the predictive value of RDW and poor functional outcomes in acute stroke.

The effect of emotional distress on functional outcomes in acute stroke patients.

To investigate the effect of emotional distress on functional outcomes in acute stroke patients. The study included 91 patients (51 females and 40 males) who were followed up with a diagnosis of acute stroke in the Neurology Department of Suleyman Demirel University Training and Research Hospital. The treatment programs of patients progressed in accordance with the functional level. Demographic data of age, gender, and educational level of the patients were recorded. The outcomes were evaluated with application of the patient distress scale (PDS), the functional ındependence measure (FIM), and the physiotherapy functional mobility profile (PFMP) before starting the rehabilitation program and on discharge from the clinic. The Montebello Rehabilitation Factor Score (MRFS) was used to evaluate the rehabilitation outcomes. Mean age of the cases was 68.08 ± 12.66 years. The difference points were calculated for the total scores of the result measurements as Δ PDS 3.72 ± 7.18, ΔFIM 8.74 ± 15.15, and Δ PFMP 4.96 ± 8.82. The MRFS effect points were determined as 0.19 ± 0.31, and the MRFS performance points as 0.03 ± 0.07. A statistically significant negative correlation was determined between Δ FIM, ΔPFMP, MRFS effect points, MRFS performance points, and Δ PDS points (P < 0.01). The results of the study showed that acute stroke patients with a good emotional state had better functional outcomes. It can be concluded that evaluating the emotional state and existing problems while planning of rehabilitation programs will make a positive contribution to both the functional and emotional states of acute stroke patients.

The experience of using thrombolysis in patients with acute disturbances of cerebral circulation: efficacy, safety, predictors of outcome and hemorrhagic transformation

To evaluate neurological and functional outcomes of early stage of ischemic stroke, their determining factors and predictors of hemorrhagic transformation in patients who received thrombolysis. A retrospective analysis of 147 patients, who underwent thrombolysis, and 127 patients, matched for basic parameters, who did not receive thrombolysis, was performed. Anamnesis, results of clinical examination, a spectrum of laboratory-instrumental parameters were evaluated. Functional status was assessed at discharge from the hospital using the Rivermead mobility index and the modified Rankin scale. Along with standard computed tomography (CT) at admission and after 24h, 73 patients receiving thrombolysis underwent CT-perfusion examination. The insufficient number of patients (37%) are admitted to a hospital in the first 2 h after stroke. The high prevalence of cardioembolic stroke and aphasia disorders in patients treated with thrombolysis was identified compared to the control group. CT revealed acute cerebral infarction in 14% of patients admitted within 2h. CT-perfusion examination determined brain ischemia only in half of patients. There was a low prevalence of symptom hemorrhagic transformation (0.7%). Thrombolysis was correlated with the higher rate of good functional outcomes of acute stroke, reduced neurological deficit, better mobility at discharge and shorter duration of the first rehabilitation period. Age, smoking, Rankin scale score at baseline, acute infarction on the primary CT, pathogenetic variant of stroke, myocardial hypertrophy, atherosclerosis of carotid arteries and volume of MRI lesions were the main factors associated with the efficacy of thrombolysis. The main predictors of hemorrhagic transformation were the severity of stroke, glomerular filtration rate, atrial fibrillation, treatment with antiaggregants before admission and hemispheric stroke. The analysis has demonstrated the safety and efficacy of thrombolysis in ischemic stroke in real clinical practice of a regional Vascular center.

Clot Imaging in Large Vessel Occlusion Strokes.

Advances in mechanical thrombectomy techniques have resulted in improved, recanalization and functional outcomes in acute stroke, as demonstrated in recent, randomized trials comparing mechanical thrombectomy with thrombolysis. In conjunction with the technological advancements in thrombectomy devices, there has been better appreciation of stricter patient selection criteria for endovascular therapy based on pre-procedural imaging, including clot location, infarct volume, and penumbral territory at risk. Pre-procedural imaging performed to assess suitability for endovascular therapy commonly provides information on clot characteristics, such as clot location, length, density, and susceptibility, which can influence and may predict the efficacy of intravenous and endovascular treatments. The purpose of this review is to evaluate the role of clot imaging in acute large vessel occlusion strokes and discuss the relevance of clot imaging to thrombolytic and endovascular therapy.

Effect of early and intensive rehabilitation in acute stroke patients: retrospective pre-/post-comparison in Japanese hospital

Purpose: There is little high-quality or large-scale clinical research focusing on the effect of early and intensive rehabilitation in Eastern countries. This study aimed to determine whether an early and intensive rehabilitation program in a Japanese hospital affects functional outcomes of acute stroke patients.Methods: In total, 1588 stroke patients were investigated. A maintained database of all hospitalized acute stroke patients admitted to our facility over two consecutive 2-year periods was reviewed. We relaunched of a new rehabilitation program to be earlier and more intensive at the midpoint of this two periods. The functional outcomes of the patients in the first 2-year period and the subsequent 2-year period were compared.Results: The total time of rehabilitation exercises per day was significantly increased from the first period to the second period. The number of patients who started rehabilitation within 24 h after admission was significantly increased in the patients admitted during the second period compared with those admitted during the first period. The Functional Independence Measure (FIM) efficiency was significantly higher in the patients admitted during the second period than in those admitted during the first period.Conclusions: An early and intensive rehabilitation program in a Japanese hospital affects functional outcomes of acute stroke patients.Implications for RehabilitationEarly and intensive rehabilitation for the stroke patients is an effective means of improving FIM score.Early and intensive rehabilitation affects the improvement of FIM efficiency without increasing adverse events.

Lower serum uric acid level strongly predict short-term poor functional outcome in acute stroke with normoglycaemia: a cohort study in China

BackgroundConflicting results on the correlation between hyperuricemia and the prognosis of stroke had been reported and the close association between serum uric acid (SUA) and abnormal glycomatabolism might further complicate the assessment of the correlation. We aimed to investigate SUA in predicting the prognosis of acute stroke in different glycometabolism status.MethodsA total of 2907 patients aged from 18 to 85 (1220 diabetes mellitus (DM), 777 prediabetes and 910 normoglycemia) were selected from the Abnormal Glucose Regulation in Patients with Acute Stroke across China (ACROSS-China) study. The patients were divided into groups according to the SUA quartile as well as decile. The correlations between SUA and the poor outcome (mRS > 2) at discharge were assessed stratified by glucose metabolism status. Multivariate logistic regression was used to analyze the potential risk factors of poor in-hospital outcome of stroke and the risk-adjustment of the correlation between SUA and the prognosis of stroke. P < 0.05 was considered statistically significant.ResultsSUA were divided first as Quartile1 to 4 (Quartile1 < 221 μmol L−1; Quartile2 (221–286) μmol L−1; Quartile3 (286–352) μmol L−1 and Quartile4 > 352 μmol L−1), then as decile1 to 10. In normoglycaemia, SUA quartiles, deciles and continuous SUA concentration were independently significantly associated with poor outcome. Q1 was independently associated with the higher possibility of poor functional outcome (compared to Q4, odds ratios (ORs) with 95% confidential interval (CI) was 3.79 (1.23–8.67) in Q1); Lower level of SUA in DM was also associated with poor functional outcome at discharge compared to the highest level of SUA(Q4)(OR with 95% CI, 2.07 (1.05–4.08)), however, lower SUA level was also related to severer stroke at admission in DM as well as in prediabetes (P < 0.001 in DM and 0.023 in prediabetes) and severer stroke resulted in worse functional outcome at discharge (OR with 95% CI, 12.15 (8.08–18.21) in DM and 11.58 (7.50–23.25) in prediabetes). But in normoglycamic stroke, SUA levels did not differ in stroke severity at admission (P = 0.066).ConclusionsLow SUA level (<221 μmol L−1) independently and strongly predicts the short-term poor functional outcome in acute stroke with normoglycaemia other than diabetes or prediabetes.

Brachial-ankle pulse wave velocity for predicting functional outcome in acute stroke.

We investigated whether the brachial-ankle pulse wave velocity (baPWV) has prognostic value for predicting functional outcome after acute cerebral infarction and whether the prognostic value differs between stroke subtypes. We included 1091 consecutive patients with first-ever acute cerebral infarction who underwent baPWV measurements. Stroke subtypes were classified using the Trial of Org 10172 in Acute Stroke Treatment classification. Poor functional outcomes were defined as modified Rankin Scale score >2 at 3 months after stroke onset. We noted that 181 (16.59%) patients had a poor functional outcome. In multivariate logistic regression, patients in the highest tertile of baPWV (>22.25 m/s) were found to be at increased risk for poor functional outcome (adjusted odds ratio, 1.88; 95% confidence interval, 1.06-3.40) compared with those in the lowest tertile (<17.55 m/s). No significant interaction between baPWV and stroke subtype was noted. Receiver operating characteristic curve analysis indicated that the addition of baPWV to the prediction model significantly improved the discrimination ability for poor functional outcome. baPWV has an independent prognostic value for predicting functional outcome after acute cerebral infarction. The prognostic value did not differ according to the stroke subtype.

Impact of macroeconomic status on prehospital management, in-hospital care and functional outcome of acute stroke in China

SUMMARY: Aim: To examine the association between gross regional product (GRP) per capita and prehospital management, in-hospital quality of care and functional outcome after stroke. Methods: The study was based on the China National Stroke Registry between 2007 and 2008. Based on the average GRP per capita in 2008, provinces in China were divided into developed and underdeveloped areas. Two variables and ten performance measures were used as quality indicators for prehospital management and in-hospital care, respectively. Good functional outcome was defined as a modified Rankin Scale score ≤2 at discharge. A summary composite measure was calculated by using an opportunity-based score. A generalized estimation equation was performed to adjust for confounders. Results: For ischemic stroke (acute ischemic stroke/transient ischemic attack), compared with patients in the underdeveloped area (n = 7573), those in the developed area (n = 8516) received better prehospital management (adjusted odds ratio [OR]: 1.03...

Abstract WMP66: Enrollment in a Pre-hospital Stroke Trial: Common Reasons for Patient Non- Enrollment

Background: Enrolling patients in the field is a promising strategy to facilitate entry of subjects within the first 1 to 2 hours after symptom onset into clinical trials for acute stroke treatment. The Field Administration of Stroke Therapy Magnesium (FAST-MAG) Trial is the first multicenter study to implement eliciting informed consent by cell phone between patients or their legally authorized representatives (LARs) and off- site enrolling physician-investigators. Call yield and profile of screen failures observed over the course of the study are reported. Methods: FAST-MAG is a phase 3 trial to evaluate field-initiated magnesium sulfate as a neuroprotective agent to improve the long-term functional outcome in acute stroke. The outcomes of these attempted enrollment calls from 362 participating ambulances to the eight central English and Spanish-speaking enrolling physician-investigators were tracked prospectively from 1/2012 to 1/2005. Results: Over seven years, 3,726 calls were made to enrolling physicians. Of these, 1478 (40%) resulted in trial enrollments. Among 2248 non-enrollment calls, the five most common reasons for were: physician’s determination of last known well time was longer than two hours (19%), pre-existing condition which could confound outcome evaluation (18%), patient deemed not competent to provide informed consent and no LAR available (12%), rapidly improving neurological deficit (9%), patient not English or Spanish speaking (6%). Phone connection difficulties accounted for only 2.7% of screen failures, whereas 4.2% were competent patients and 11% were LARs refusing participation. Yearly enrollment yeilds did not change significantly throughout the study Conclusion: Two of every five calls from the field to FM enrolling physicians resulted in trial enrollment. Enrollment yields were consistent throughout the study.

A practical assessment of magnetic resonance diffusion-perfusion mismatch in acute stroke: observer variation and outcome

MR diffusion/perfusion mismatch may help identify patients for acute stroke treatment, but mixed results from clinical trials suggest that further evaluation of the mismatch concept is required. To work effectively, mismatch should predict prognosis on arrival at hospital. We assessed mismatch duration and associations with functional outcome in acute stroke. We recruited consecutive patients with acute stroke, recorded baseline clinical variables, performed MR diffusion and perfusion imaging and assessed 3-month functional outcome. We assessed practicalities, agreement between mismatch on mean transit time (MTT) or cerebral blood flow (CBF) maps, visually and with lesion volume, and the relationship of each to functional outcome. Of 82 patients starting imaging, 14 (17%) failed perfusion imaging. Overall, 42% had mismatch (56% at <6 h; 41% at 12-24 h; 23% at 24-48 h). Agreement for mismatch by visual versus volume assessment was fair using MTT (kappa 0.59, 95% CI 0.34-0.84) but poor using CBF (kappa 0.24, 95% CI 0.01-0.48). Mismatch by either definition was not associated with functional outcome, even when the analysis was restricted to just those with mismatch. Visual estimation is a reasonable proxy for mismatch volume on MTT but not CBF. Perfusion is more difficult for acute stroke patients than diffusion imaging. Mismatch is present in many patients beyond 12 h after stroke. Mismatch alone does not distinguish patients with good and poor prognosis; both can do well or poorly. Other factors, e.g. reperfusion, may influence outcome more strongly, even in patients without mismatch.

Percent Change on the National Institutes of Health Stroke Scale: A Useful Acute Stroke Outcome Measure

A single optimal outcome measure in acute stroke has not been established. Changes in neurologic deficits might be useful outcome measures in acute stroke because they can measure within-subject changes on the entire spectrum of the scales starting at baseline. We tested the ability of percent National Institutes of Health Stroke Scale (NIHSS) score change (baseline-3 months) to predict the traditional functional outcomes in acute stroke (modified Rankin Scale [mRS], Barthel Index, Glasgow Outcome Scale, final NIHSS score). We analyzed data sets from two acute stroke clinical trials involving 44 clinical research centers throughout the United States and 1899 randomized patients. The percent NIHSS score change predicted functional outcomes very well, all areas under the curve of 0.90 or greater with all P values less than .001 in receiver operating characteristic analysis. In the National Institute of Neurological Disorders and Stroke Recombinant Tissue Plasminogen Activator (rt-PA) Acute Stroke Trial, benefit from rt-PA was confirmed by a greater improvement on the NIHSS score than with placebo (67% v 50%, P < .002). In moderate stroke severity (baseline NIHSS score 7-15) an improvement of at least 55% was the best predictor of functional independence at 3 months (mRS <or= 2). This novel approach to the NIHSS score as an outcome measure in acute stroke appears to be an additional useful analytic and communication tool.

Using Mismatch on MRI to Select Thrombolytic Responders

Our ability to image the ischemic penumbra in vivo raises the attractive possibility of individualized selection of acute therapy, particularly with thrombolytic agents. In other words, clinicians could potentially use magnetic resonance (MR) mismatch as a physiological tissue clock in acute stroke and allow selection of therapy beyond the accepted time windows. Indeed, this was foreshadowed nearly 25 years ago by the originators of the penumbral concept.1 As indicated by Schellinger and Fiebach, there is a body of evidence from small phase II studies to …

Predicting functional outcome in acute stroke: comparison of a simple six variable model with other predictive systems and informal clinical prediction

Background: Statistical models that predict functional outcome after stroke using six simple variables (SSV) have recently been developed and validated. Objective: To compare the accuracy of these models with other...