Fluid-Attenuated Inversion Recovery Vascular Hyperintensity Topography, Novel Imaging Marker for Revascularization in Middle Cerebral Artery Occlusion.

BACKGROUND AND PURPOSE: In acute arterial occlusion, fluid-attenuated inversion recovery vascular hyperintensity (FVH) has been linked to slow flow in leptomeningeal collaterals and cerebral hypoperfusion, but the impact on clinical outcome is still controversial. In this study, we aimed to investigate the association between FVH topography or FVH-Alberta Stroke Program Early CT Score (ASPECTS) pattern and outcome in acute M1-middle cerebral artery occlusion patients with endovascular treatment. METHODS: We included acute M1-middle cerebral artery occlusion patients treated with endovascular therapy (ET). All patients had diffusion-weighted imaging (DWI) and fluid-attenuated inversion recovery before ET. Distal FVH-ASPECTS was evaluated according to distal middle cerebral artery-ASPECT area (M1-M6) and acute DWI lesion was also reviewed. The presence of FVH inside and outside DWI-positive lesions was separately analyzed. Clinical outcome after ET was analyzed with respect to different distal FVH-ASPECTS topography. RESULTS: Among 101 patients who met inclusion criteria for the study, mean age was 66.2±17.8 years and median National Institutes of Health Stroke Scale was 17.0 (interquartile range, 12.0-21.0). FVH-ASPECTS measured outside of the DWI lesion was significantly higher in patients with good outcome (modified Rankin Scale [mRS] score of 0-2; 8.0 versus 4.0, P<0.001). Logistic regression demonstrated that FVH-ASPECTS outside of the DWI lesion was independently associated with clinical outcome of these patients (odds ratio, 1.3; 95% confidence interval, 1.06-1.68; P=0.013). FVH-ASPECTS inside the DWI lesion was associated with hemorrhagic transformation (odds ratio, 1.3; 95% confidence interval, 1.04-1.51; P=0.019). CONCLUSIONS: Higher FVH-ASPECTS measured outside the DWI lesion is associated with good clinical outcomes in patients undergoing ET. FVH-ASPECTS measured inside the DWI lesion was predictive of hemorrhagic transformation. The FVH pattern, not number, can serve as an imaging selection marker for ET in acute middle cerebral artery occlusion.

Enrollment Yield and Reasons for Screen Failure in a Large Prehospital Stroke Trial.

BACKGROUND AND PURPOSE: The enrollment yield and reasons for screen failure in prehospital stroke trials have not been well delineated. METHODS: The Field Administration of Stroke Therapy-Magnesium (FAST-MAG) trial identified patients for enrollment using a 2 stage screening process-paramedics in person followed by physician-investigators by cell phone. Outcomes of consecutive screening calls from paramedics to enrolling physician-investigators were prospectively recorded. RESULTS: From 2005 to 2012, 4458 phone calls were made by paramedics to physician-investigators, an average of 1 call per vehicle every 135.7 days. A total of 1700 (38.1%) calls resulted in enrollments. The rate of enrollment of stroke mimics was 3.9%. Among the 2758 patients not enrolled, 3140 reasons for screen failure were documented. The most common reasons for nonenrollment were >2 hours from last known well (17.2%), having a prestroke condition causing disability (16.1%), and absence of a consent provider (9.5%). Novel barriers for phone informed consent specific to the prehospital setting were infrequent, but included: cell phone connection difficulties (3.2%), patient being hard of hearing (1.4%), insufficient time to complete consent (1.3%), or severely dysarthric (1.3%). CONCLUSIONS: In this large, multicenter prehospital trial, nearly 40% of every calls from the field to physician-investigators resulted in trial enrollments. The most common reasons for nonenrollment were out of window last known well time, prestroke confounding medical condition, and absence of a consent provider. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00059332.

DWI Lesion Patterns Predict Outcome in Stroke Patients with Thrombolysis.

BACKGROUND: Lesion patterns may predict prognosis after acute ischemic stroke within the middle cerebral artery (MCA) territory; yet it remains unclear whether such imaging prognostic factors are related to patient outcome after intravenous thrombolysis. AIMS: The aim of this study is to investigate the clinical outcome after intravenous thrombolysis in acute MCA ischemic strokes with respect to diffusion-weighted imaging (DWI) lesion patterns. METHODS: Consecutive acute ischemic stroke cases of the MCA territory treated over a 7-year period were retrospectively analyzed. All acute MCA stroke patients underwent a MRI scan before intravenous thrombolytic therapy was included. DWI lesions were divided into 6 patterns (territorial, other cortical, small superficial, internal border zone, small deep, and other deep infarcts). Lesion volumes were measured by dedicated imaging processing software. Favorable outcome was defined as modified Rankin scale (mRS) of 0-2 at 90 days. RESULTS: Among the 172 patients included in our study, 75 (43.6%) were observed to have territorial infarct patterns or other deep infarct patterns. These patients also had higher baseline NIHSS score (p < 0.001), a higher proportion of large cerebral artery occlusions (p < 0.001) and larger infarct volume (p < 0.001). Favorable outcome (mRS 0-2) was achieved in 89 patients (51.7%). After multivariable analysis, groups with specific lesion patterns, including territorial infarct and other deep infarct pattern, were independently associated with favorable outcome (OR 0.40; 95% CI 0.16-0.99; p = 0.047). CONCLUSIONS: Specific lesion patterns predict differential outcome after intravenous thrombolysis therapy in acute MCA stroke patients.

The Ethnic/Racial Variations of Intracerebral Hemorrhage (ERICH) study protocol.

BACKGROUND AND PURPOSE: Epidemiological studies of intracerebral hemorrhage (ICH) have consistently demonstrated variation in incidence, location, age at presentation, and outcomes among non-Hispanic white, black, and Hispanic populations. We report here the design and methods for this large, prospective, multi-center case-control study of ICH. METHODS: The Ethnic/Racial Variations of Intracerebral Hemorrhage (ERICH) study is a multi-center, prospective case-control study of ICH. Cases are identified by hot-pursuit and enrolled using standard phenotype and risk factor information and include neuroimaging and blood sample collection. Controls are centrally identified by random digit dialing to match cases by age (±5 years), race, ethnicity, sex, and metropolitan region. RESULTS: As of March 22, 2013, 1655 cases of ICH had been recruited into the study, which is 101.5% of the target for that date, and 851 controls had been recruited, which is 67.2% of the target for that date (1267 controls) for a total of 2506 subjects, which is 86.5% of the target for that date (2897 subjects). Of the 1655 cases enrolled, 1640 cases had the case interview entered into the database, of which 628 (38%) were non-Hispanic black, 458 (28%) were non-Hispanic white, and 554 (34%) were Hispanic. Of the 1197 cases with imaging submitted, 876 (73.2%) had a 24 hour follow-up CT available. In addition to CT imaging, 607 cases have had MRI evaluation. CONCLUSIONS: The ERICH study is a large, case-control study of ICH with particular emphasis on recruitment of minority populations for the identification of genetic and epidemiological risk factors for ICH and outcomes after ICH.

Variability in the use of intravenous thrombolysis for mild stroke: experience across the SPOTRIAS network.

BACKGROUND: Current guidelines do not define the lower severity threshold for thrombolysis. In this study, we describe the variability of treatment of mild stroke patients across a network of academic stroke centers. METHODS: Stroke centers within the Specialized Program of Translational Research in Acute Stroke (SPOTRIAS) prospectively collect data on patients treated with intravenous recombinant tissue plasminogen activator (IV rt-PA), including demographics, pretreatment National Institutes of Health Stroke Scale (NIHSS) scores, and in-hospital mortality. We examined the variability in proportion of total tissue plasminogen activator-treated patients in the NIHSS categories (0-3, 4-5, or ≥ 6) and associated outcomes. RESULTS: A total of 2514 patients with reported NIHSS scores were treated with IV rt-PA between January 1, 2005 and December 31, 2009. The proportion of patients with mild stroke (NIHSS scores of 0-3) who were treated with IV rt-PA varied substantially across the centers (2.7-18.0%; P < .001). There were 5 deaths in the 256 treated with an NIHSS score of 0-3 (2.0%). The proportion of treated patients across the network with an NIHSS score of 0 to 3 increased from 4.8% in 2005 to 10.7% in 2009 (P = .001). CONCLUSIONS: There is substantial variability in the proportion of treated patients who have mild stroke across the SPOTRIAS centers, reflecting a paucity of data on how to best treat patients with mild stroke. Randomized trial data for this group of patients are needed to clarify the use of rt-PA in patients with the mildest strokes.

Thrombus branching and vessel curvature are important determinants of middle cerebral artery trunk recanalization with Merci thrombectomy devices.

BACKGROUND AND PURPOSE: Determinants of successful recanalization likely differ for Merci thrombectomy and intra-arterial pharmacological fibrinolysis interventions. Although the amount of thrombotic material to be digested is an important consideration for chemical lysis, mechanical debulking may be more greatly influenced by other target lesion characteristics. METHODS: In consecutive patients with acute ischemic stroke treated with Merci thrombectomy for middle cerebral artery M1 occlusions, we analyzed the influence on recanalization success and clinical outcome of target thrombus size (length) and shape (curvature and branching) on pretreatment T2* gradient echo MRI. RESULTS: Among 65 patients, pretreatment MRI showed susceptibility vessel signs in 45 (69%). Thrombus length averaged 13.03 mm (range, 5.56-34.91) and irregular shape (curvature or branching) was present in 17 of 45 (38%). Presence and length of susceptibility vessel signs did not predict recanalization or good clinical outcome. Substantial recanalization (Thrombolysis In Cerebral Infarction 2b or 3) and good clinical outcome (modified Rankin Scale score ≤2) were more frequent with regular than irregular susceptibility vessel signs shape (57% versus 18%, P=0.013; 39% versus 6%, P=0.017). On multiple regression analysis, the only independent predictor of substantial recanalization was irregular susceptibility vessel signs (OR, 0.16; 95% CI, 0.04-0.69; P=0.014); and leading predictors of good clinical outcome were baseline National Institutes of Health Stroke Scale (OR, 1.20; 95% CI, 1.03-1.40; P= 0.019) and irregular susceptibility vessel signs (OR, 9.36; 95% CI, 0.98-89.4; P=0.052). CONCLUSIONS: Extension of thrombus into middle cerebral artery division branches and curving shape of the middle cerebral artery stem, but not thrombus length, decrease technical and clinical success of Merci thrombectomy in M1 occlusions.

Impact of acute ischemic stroke treatment in patients >80 years of age: the specialized program of translational research in acute stroke (SPOTRIAS) consortium experience.

BACKGROUND AND PURPOSE: Few studies have addressed outcomes among patients ≥80 years treated with acute stroke therapy. In this study, we outline in-hospital outcomes in (1) patients ≥80 years compared with their younger counterparts; and (2) those over >80 years receiving intra-arterial therapy (IAT) compared with those treated with intravenous recombinant tissue-type plasminogen activator (IV rtPA). METHODS: Stroke centers within the Specialized Program of Translational Research in Acute Stroke (SPOTRIAS) prospectively collected data on all patients treated with IV rtPA or IAT from January 1, 2005, to December 31, 2010. IAT was defined as receiving any endovascular therapy; IAT was further divided into bridging therapy when the patient received both IAT and IV rtPA and endovascular therapy alone. In-hospital mortality was compared in (1) all patients aged ≥80 years versus younger counterparts; and (2) IAT, bridging therapy, and endovascular therapy alone versus IV rtPA only among those age ≥80 years using multivariable logistic regression. An age-stratified analysis was also performed. RESULTS: A total of 3768 patients were included in the study; 3378 were treated with IV rtPA alone and 808 with IAT (383 with endovascular therapy alone and 425 with bridging therapy). Patients ≥80 years (n=1182) had a higher risk of in-hospital mortality compared with younger counterparts regardless of treatment modality (OR, 2.13; 95% CI, 1.60-2.84). When limited to those aged ≥80 years, IAT (OR, 0.95; 95% CI, 0.60-1.49), bridging therapy (OR, 0.82; 95% CI, 0.47-1.45), or endovascular therapy alone (OR, 1.15; 95% CI, 0.64-2.08) versus IV rtPA were not associated with increased in-hospital mortality. CONCLUSIONS: IAT does not appear to increase the risk of in-hospital mortality among those aged >80 years compared with IV thrombolysis alone.

Leukoaraiosis predicts parenchymal hematoma after mechanical thrombectomy in acute ischemic stroke.

BACKGROUND AND PURPOSE: The purpose of this study was to determine whether leukoaraiosis (LA) predicts hemorrhagic transformation and poor outcome in patients with acute ischemic stroke treated by mechanical thrombectomy. METHODS: We retrospectively analyzed patients with anterior circulation stroke treated with Merci devices and identified LA in the deep white matter (DWM) and periventricular white matter on the preintervention MR images. We dichotomized patients into those with moderate or severe LA in the DWM versus those without. Hemorrhage rates and outcomes were evaluated between 2 groups. We analyzed the association of moderate or severe LA with hemorrhagic transformation and poor outcome. RESULTS: Twenty-six of 105 patients had moderate or severe LA in the DWM. Patients with moderate or severe LA in the DWM were older, had more severe neurological deficits and worse outcome, had higher rates of hemorrhagic transformation and parenchymal hematoma, but had equivalent rates of hemorrhagic infarct and subarachnoid hemorrhage when compared with those without. Patients with only periventricular LA did not have a higher rate of parenchymal hematoma. Moderate or severe LA in the DWM was an independent predictor of hemorrhagic transformation (OR, 3.4; P=0.019) and parenchymal hematoma (OR, 6.3; P=0.005). Patients with parenchymal hematoma were less often independent (modified Rankin Scale≤2, 3.8% versus 32.5%; P=0.003) and had greater in-hospital mortality (50% versus 10.4%; P<0.001). CONCLUSIONS: Moderate or severe LA in the DWM increases the risk of parenchymal hematoma after Merci thrombectomy for patients with acute stroke. These findings require validation in a larger prospective study.

Anterior choroidal artery ischaemic patterns predict outcome of carotid occlusion.

OBJECTIVE: To investigate whether anterior choroidal artery (AChA) territory sparing or AChA infarction restricted to the medial temporal lobe (MT), implying good collateral status, predicts good outcome, defined as modified Rankin Scale 0-2, at discharge in acute internal carotid artery (ICA) occlusion. METHODS: The authors studied consecutive patients with acute ICA occlusion admitted to an academic medical centre between January 2002 and August 2010, who underwent MRI followed by conventional angiography. The pattern of AChA involvement on initial diffusion-weighted imaging was dichotomised as spared or MT only versus other partial or full. The association of AChA infarct patterns and good outcome at discharge was calculated by multivariate logistic regression with adjustment. RESULTS: For the 60 patients meeting entry criteria, mean age was 68.3 years and median admission NIH Stroke Scale score was 19. AChA territory was spared or restricted to the MT in 27 patients and other partially involved or fully involved in 33 patients. AChA territory spared or ischaemia restricted to MT only, compared with other partial infarct patterns or full infarct, was independently associated with good discharge outcome (44.4% vs 12.1%, OR 7.24, 95% CI 1.32 to 39.89, p=0.023). CONCLUSION: In acute ICA occlusion, the absence of AChA infarction or restriction to the MT is an independent predictor of good discharge outcome. Analysis of AChA infarct patterns may improve early prognostication and decision-making.

Weighting components of composite end points in clinical trials: an approach using disability-adjusted life-years.

BACKGROUND AND PURPOSE: Conventional analysis of vascular prevention trials assigns equal weight to disparate vascular events in a composite end point at variance with the public's perception of their differential impact on health outcome. This study sought to apply the disability-adjusted life-year (DALY) metric to differential weighting individual vascular end points in trial analyses. METHODS: DALY values for the most common major end points in vascular prevention trials (nonfatal myocardial infarction, nonfatal stroke, and vascular death), were derived by using World Health Organization Global Burden of Disease Project methodology. The standardized DALYs for each event were applied to recent major primary and secondary vascular prevention trials and to hypothetical model trials. RESULTS: Standardized DALYs lost were 7.63 for nonfatal stroke, 5.14 for nonfatal myocardial infarction, and 11.59 for vascular death. In the published trials analyses, the direction of treatment effects was consistent between DALY and standard event analysis, but the rank order of treatment effect changed for 10 of 18 trials. The DALY analysis also permitted derivation of number-needed-to-treat values to gain 1 DALY: 2.1 for anticoagulation in atrial fibrillation, 2.7 for carotid endarterectomy in symptomatic stenosis, and 4.7 for clopidogrel added to aspirin in acute coronary syndrome. Hypothetical trial analyses demonstrated that the DALY metric more finely discriminates treatment effects. CONCLUSIONS: Compared with a nonfatal myocardial infarction, a nonfatal stroke causes a 1.48-fold greater loss and vascular death a 2.25-fold greater loss of DALY. DALY analysis integrates these valuations in a summary metric reflecting the net impact of therapy on patient and societal health, complementing conventional end point analyses.

CT and MRI early vessel signs reflect clot composition in acute stroke.

BACKGROUND AND PURPOSE: The purpose of this study was to provide the first correlative study of the hyperdense middle cerebral artery sign (HMCAS) and gradient-echo MRI blooming artifact (BA) with pathology of retrieved thrombi in acute ischemic stroke. METHODS: Noncontrast CT and gradient-echo MRI studies before mechanical thrombectomy in 50 consecutive cases of acute middle cerebral artery ischemic stroke were reviewed blinded to clinical and pathology data. Occlusions retrieved by thrombectomy underwent histopathologic analysis, including automated quantitative and qualitative rating of proportion composed of red blood cells (RBCs), white blood cells, and fibrin on microscopy of sectioned thrombi. RESULTS: Among 50 patients, mean age was 66 years and 48% were female. Mean (SD) proportion was 61% (±21) fibrin, 34% (±21) RBCs, and 4% (±2) white blood cells. Of retrieved clots, 22 (44%) were fibrin-dominant, 13 (26%) RBC-dominant, and 15 (30%) mixed. HMCAS was identified in 10 of 20 middle cerebral artery stroke cases with CT with mean Hounsfield Unit density of 61 (±8 SD). BA occurred in 17 of 32 with gradient-echo MRI. HMCAS was more commonly seen with RBC-dominant and mixed than fibrin-dominant clots (100% versus 67% versus 20%, P=0.016). Mean percent RBC composition was higher in clots associated with HMCAS (47% versus 22%, P=0.016). BA was more common in RBC-dominant and mixed clots compared with fibrin-dominant clots (100% versus 63% versus 25%, P=0.002). Mean percent RBC was greater with BA (42% versus 23%, P=0.011). CONCLUSIONS: CT HMCAS and gradient-echo MRI BA reflect pathology of occlusive thrombus. RBC content determines appearance of HMCAS and BA, whereas absence of HMCAS or BA may indicate fibrin-predominant occlusive thrombi.

Prognostic value of Framingham Cardiovascular Risk Score in hospitalized stroke patients.

The Framingham Coronary Risk Score (FCRS) is based on several factors, including age, sex, total cholesterol, high-density lipoprotein cholesterol, systolic blood pressure, presence of diabetes, and cigarette smoking. Some of these factors are individually linked with acute stroke outcomes. We explored whether FCRS could predict outcome in patients hospitalized with recent stroke. We collected data on consecutive patients hospitalized for ischemic stroke over a 3-year period. Patients with known coronary artery disease were excluded. Discharge outcomes assessed were neurologic deficit (National Institutes of Health Stroke Scale [NIHSS] score), death or disability (modified Rankin Scale [mRS] score ≥2), and discharge to home directly from the hospital. The independent effect of FCRS on these outcomes was evaluated using multivariate regression analysis. During the study period, 434 patients with ischemic stroke met entry criteria (mean age, 64.5 years; 54% females). Median FCRS score was 8%. After adjusting for confounders, higher FCRS score was associated with an increased likelihood of death or being disabled at discharge (odds ratio [OR]=4.9; 95% confidence interval [CI]=0.98-24.1; P=.05), and a decreased likelihood of being discharged directly to home (OR=0.18; 95% CI=0.04-0.86; P=.032), but not with discharge NIHSS score. Higher FCRS in hospitalized ischemic stroke patients is associated with death or disability at discharge and a lower likelihood of being discharged directly to home. Along with indexing the long-term risk of cardiovascular events, this widely known, easily calculable score provides clinically relevant short-term prognostic information following ischemic stroke.

Predictors of subarachnoid hemorrhage in acute ischemic stroke with endovascular therapy.

BACKGROUND AND PURPOSE: Subarachnoid hemorrhage (SAH) is a potential hemorrhagic complication after endovascular intracranial recanalization. The purpose of this study was to describe the frequency and predictors of SAH in acute ischemic stroke patients treated endovascularly and its impact on clinical outcome. METHODS: Acute ischemic stroke patients treated with primary mechanical thrombectomy, intra-arterial thrombolysis, or both were analyzed. Postprocedural computed tomography and magnetic resonance images were reviewed to identify the presence of SAH. We assessed any decline in the National Institutes of Health Stroke Scale score 3 hours after intervention and in the outcomes at discharge. RESULTS: One hundred twenty-eight patients were treated by primary thrombectomy with MERCI Retriever devices, whereas 31 were treated by primary intra-arterial thrombolysis. Twenty patients experienced SAH, 8 with pure SAH and 12 with coexisting parenchymal hemorrhages. SAH was numerically more frequent with primary thrombectomy than in the intra-arterial thrombolysis groups (14.1% vs 6.5%, P = 0.37). On multivariate analysis, independent predictors of SAH were hypertension (odds ratio = 5.39, P = 0.035), distal middle cerebral artery occlusion (odds ratio = 3.53, P = 0.027), use of rescue angioplasty after thrombectomy (odds ratio = 12.49, P = 0.004), and procedure-related vessel perforation (odds ratio = 30.72, P < 0.001). Patients with extensive SAH or coexisting parenchymal hematomas tended to have more neurologic deterioration at 3 hours (28.6% vs 0%, P = 0.11), to be less independent at discharge (modified Rankin Scale ≤ 2; 0% vs 15.4%, P = 0.5), and to experience higher mortality during hospitalization (42.9% vs 15.4%, P = 0.29). CONCLUSIONS: Procedure-related vessel perforation, rescue angioplasty after thrombectomy with MERCI devices, distal middle cerebral artery occlusion, and hypertension were independent predictors of SAH after endovascular therapy for acute ischemic stroke. Only extensive SAH or SAH accompanied by severe parenchymal hematomas may worsen clinical outcome at discharge.

Optimizing screening and management of asymptomatic coronary artery disease in patients with stroke and patients with transient ischemic attack.

BACKGROUND AND PURPOSE: The feasibility of implementing an expert consensus guideline recommending use of a stroke patient's profile to manage undiagnosed coronary artery disease remains unclear. METHODS: Following a guideline-based algorithm, we screened consecutive patients with ischemic stroke and patients with transient ischemic attack for asymptomatic coronary artery disease using the Framingham Heart Study Coronary Risk Score (FCRS) cutoff of high risk (> or = 20%) for experiencing a hard coronary artery disease event over a 10-year period. Patients with high FCRS received dobutamine stress echocardiogram outpatient screening, additional treatment (beta-blocker), or further management (cardiologist referral). RESULTS: From July 2004 to September 2007, among 693 patients, 501 (72%) met study criteria, of which 80 (16%) had FCRS > or = 20%. Elevated serum glucose, nonhigh-density lipoprotein, triglycerides, homocysteine, glycosylated hemoglobin as well as large vessel atherosclerotic stroke mechanism were more frequent in high versus low FCRS patients (P<0.05). Among high FCRS patients, 35 (44%) had dobutamine stress echocardiogram performed. Leading reasons for dobutamine stress echocardiogram nonperformance were patient noncompliance (42%) and primary care physician refusal (33%). CONCLUSIONS: Screening for coronary artery disease risk using FCRS is feasible in hospitalized patients with stroke, but outpatient adherence to stress testing is challenging largely due to patient and primary care physician-related factors.

Simultaneous ring voice-over-Internet phone system enables rapid physician elicitation of explicit informed consent in prehospital stroke treatment trials.

BACKGROUND: Cellular phone conversations between on-scene patients or their legally authorized representatives (LARs) and off-scene enrolling physician-investigators require immediate and reliable connection systems to obtain explicit informed research consent in prehospital treatment trials. METHODS: The NIH Field Administration of Stroke Therapy-Magnesium (FAST-MAG) Trial implemented a voice-over-internet protocol (VOIP) simultaneous ring system (multiple investigator cell phones called simultaneously and first responder connected to call) to enable physician-investigators to elicit consent immediately from competent patients or LARs encountered by 228 ambulances enrolling patients in a multicenter prehospital stroke trial. For 1 month, the number, origin, duration, and yield of enrolling line calls were monitored prospectively. RESULTS: Six investigators were connected to 106 enrolling line calls, with no identified unanswered calls. Thirty-five percent of new patient calls yielded an enrollment. The most common reasons for non-enrollment were last known well >2 h (n = 7) and unconsentable patient without LAR available (n = 7). No non-enrollments were directly attributable to the VOIP system. In enrollments, consent was provided by the patient in 67% and a LAR in 33%. The duration of enrollment calls (mean +/- SD: 8.4 +/- 2.5 min, range 6-14) was longer than non-enrollment calls (5.5 +/- 3.5, range 2-13; p < 0.001). The median interval from last known well to study agent start was 46 min, and 70% were enrolled within 60 min of onset. CONCLUSIONS: The simultaneous ring system was reliable and effective, permitting enrollment of a substantial number of patients within the first hour after stroke onset. VOIP cellular networks with simultaneous ring are a preferred means of facilitating consent in prehospital treatment trials.

Indices of kidney dysfunction and discharge outcomes in hospitalized stroke patients without known renal disease.

BACKGROUND: The utility of clinical measurements of impairments in glomerular barrier or filtration rate among hospitalized stroke patients without known chronic kidney disease (CKD) has not been well studied. We determined whether various indices of CKD would predict discharge outcomes in persons hospitalized with a recent ischemic stroke. METHODS: Presence of proteinuria and estimated low glomerular filtration rate (GFR) <60 ml/min per 1.73 m(2) on admission were assessed in consecutive ischemic stroke and transient ischemic attack patients admitted to a university hospital over 18 months, who had no history of CKD. The primary discharge outcomes assessed (among stroke patients only) were death or disability (modified Rankin Scale score > or =2) and being discharged home directly from hospital. Independent effects of CKD indices on the outcomes were evaluated using multivariable regression modeling. RESULTS: Of 251 patients with recent ischemic cerebrovascular events, 198 ischemic stroke patients (79%), met the study criteria. In crude analyses, persons with proteinuria or low GFR were significantly more likely to die in the hospital (p < 0.05). After adjusting for confounders, proteinuria was independently linked with lower odds of going home directly from the hospital (OR = 0.38, 95% CI = 0.16-0.92) and poorer discharge functional status (OR = 3.19, 95% CI = 1.37-7.46), but low GFR was not independently related to either of these outcomes. CONCLUSIONS: Among hospitalized ischemic stroke patients without known CKD, presence of proteinuria on admission is independently associated with poorer discharge functional activity and lower likelihood of being discharged home directly. Low GFR was not related to either outcome in these patients without known CKD.

A care pathway to boost influenza vaccination rates among inpatients with acute ischemic stroke and transient ischemic attack.

BACKGROUND: Although influenza-related morbidity and mortality is high, and influenza can be a trigger for recurrent stroke, only about half of stroke survivors receive yearly influenza vaccination. Identifying new avenues through which to optimize influenza vaccination among stroke survivors is a public health need. We assessed the feasibility of integrating influenza vaccination into routine inpatient stroke care. METHODS: We designed a quality improvement project incorporating influenza vaccination into care administered to hospitalized patients with ischemic stroke and transient ischemic attack that included a standardized order and discharge checklist. Data were then prospectively collected on consecutively encountered patients with ischemic stroke and transient ischemic attack admitted to a university hospital stroke service during the influenza season of October 2007 to February 2008. Successful influenza treatment use was based on optimal rather than actual treatment, with credit for optimal treatment given if an acceptable reason for nonadministration of the vaccine was documented. RESULTS: Of 103 patients admitted during the study period, 75 (73%) were eligible for influenza vaccination (mean age 72.8 years; 51% women). Among vaccination-eligible patients, 65 (87%) received optimal influenza vaccination treatment, whereas 14 (21%) actually received the vaccination during hospitalization. Leading reason (90%) for suboptimal influenza vaccination treatment among eligible patients was that the vaccination was inadvertently not ordered on admission or at discharge. CONCLUSIONS: Influenza vaccination can be systematically incorporated into stroke hospitalization and may be a viable avenue for promptly enhancing short-term clinical outcomes among hospitalized patients with stroke during peak influenza season.

Early neutrophilia is associated with volume of ischemic tissue in acute stroke.

BACKGROUND AND PURPOSE: Few data exist on the relationship between differential subpopulations of peripheral leukocytes and early cerebral infarct size in ischemic stroke. Using diffusion-weighted MR imaging (DWI), we assessed the relationship of early total and differential peripheral leukocyte counts and volume of ischemic tissue in acute stroke. METHODS: All included patents had laboratory investigations and neuroimaging collected within 24 hours of stroke onset. Total peripheral leukocyte counts and differential counts were analyzed individually and by quartiles. DWI lesions were outlined using a semiautomated threshold technique. The relationship between leukocyte quartiles and DWI infarct volumes was examined using multivariate quartile regression. RESULTS: 173 patients met study inclusion criteria. Median age was 73 years. Total leukocyte counts and DWI volumes showed a strong correlation (Spearman rho=0.371, P<000.1). Median DWI volumes (mL) for successive neutrophil quartiles were: 1.3, 1.3, 3.2, and 20.4 (P for trend <0.001). Median DWI volumes (mL) for successive lymphocyte quartiles were: 3.2, 8.1, 1.3, and 1.5 (P=0.004). After multivariate analysis, larger DWI volume remained strongly associated with higher total leukocyte and neutrophil counts (both probability values <0.001), but not with lymphocyte count (P=0.4971). Compared with the lowest quartiles, DWI volumes were 8.7 mL and 12.9 mL larger in the highest quartiles of leukocyte and neutrophil counts, respectively. CONCLUSIONS: Higher peripheral leukocyte and neutrophil counts, but not lymphocyte counts, are associated with larger infarct volumes in acute ischemic stroke. Attenuating neutrophilic response early after ischemic stroke may be a viable therapeutic strategy and warrants further study.

Prior antiplatelet use and infarct volume in ischemic stroke.

BACKGROUND: Conflicting data exist on the role of antiplatelet agents in reducing incident ischemic stroke magnitude, but most prior studies used clinically-assessed neurologic deficit as the index of stroke extent rather than more precise volumetric measurements of infarct size. We assessed the relation of premorbid antiplatelet use to initial diffusion-weighted MRI (DWI) lesion volumes among acute ischemic stroke patients. METHODS: Consecutive patients presenting within 24 h of ischemic stroke over an 18-month period were studied. DWI lesions were outlined using a semi-automated threshold technique. Subjects were categorized into two groups: antiplatelet (AP) or no antithrombotic (NA). The relationship between prestroke antithrombotic status and DWI infarct volumes was examined using multivariate quantile regression. RESULTS: One hundred sixty-six individuals met study criteria: 75 AP and 91 NA patients. Median DWI volume was lower in the AP group than in the NA group (1.5 cc vs. 5.4 cc, p=0.031). A multivariable model (adjusting for age, history of transient ischemic attack, admission temperature, admission blood pressure, admission serum glucose, stroke onset to imaging interval, stroke mechanism, premorbid statin and antihypertensive use) demonstrated smaller infarcts in the AP vs. NA group (adjusted volume difference: -1.3 cc, 95% CI=-0.09, -2.5, p=0.037). Prior statin use, no history of TIA, large vessel atherosclerosis and microvascular ischemic disease stroke mechanism were also independently associated with reduced infarct volume. CONCLUSIONS: Prior antiplatelet treatment is independently associated with reduced cerebral infarct volume among acute ischemic stroke patients. Premorbid statin use, TIA history and stroke mechanism also predict infarct volume in ischemic stroke.

Sleep-disordered breathing and stroke.

Sleep and stroke have an important and fascinating interaction. Patients with sleep-disordered breathing present with cardiovascular heart disease, cognitive decline, and increased risk of stroke. Stroke adversely affects sleep and factors such as prolonged immobilization, chronic pain, nocturnal hypoxia, and depression, which can also adversely impact sleep quality. Obstructive sleep apnea (OSA), one of the most common and serious sleep disturbances, manifests itself in almost 50% of all stroke patients. Sleep apnea patients who experience a stroke may be at a greater impairment in their rehabilitation potential and have increased risk of secondary stroke and mortality. Given these factors, the practicing neurologist should possess the skills to appropriately recognize, rapidly diagnose, and properly manage stroke patients with OSA.