Subtle white matter intensity changes on fluid-attenuated inversion recovery imaging in patients with ischaemic stroke

Leukoaraiosis is a neuroimaging marker of small-vessel disease that is characterized by high signal intensity on fluid-attenuated inversion recovery MRI. There is increasing evidence from pathology and neuroimaging suggesting that the structural abnormalities that characterize leukoaraiosis are actually present within regions of normal-appearing white matter, and that the underlying pathophysiology of white matter damage related to small-vessel disease involves blood-brain barrier damage. In this study, we aim to verify whether leukoaraiosis is associated with elevated signal intensity on fluid-attenuated inversion recovery imaging, a marker of brain tissue free-water accumulation, in normal-appearing white matter. We performed a cross-sectional study of adult patients admitted to our hospital with a diagnosis of acute ischaemic stroke or transient ischaemic attack. Leukoaraiosis was segmented using a semi-automated method involving manual outlining and signal thresholding. White matter regions were segmented based on the probabilistic tissue maps from the International Consortium for Brain Mapping 152 atlas. Also, normal-appearing white matter was further segmented based on voxel distance from leukoaraiosis borders, resulting in five normal-appearing white matter strata at increasing voxel distances from leukoaraiosis. The relationship between mean normalized fluid-attenuated inversion recovery signal intensity on normal-appearing white matter and leukoaraiosis volume was studied in a multivariable statistical analysis using linear mixed modelling, having normal-appearing white matter strata as a clustering variable. One hundred consecutive patients meeting inclusion and exclusion criteria were selected for analysis (53% female, mean age 68 years). Mean normalized fluid-attenuated inversion recovery signal intensity on normal-appearing white matter was higher in the vicinity of leukoaraiosis and progressively lower at increasing distances from leukoaraiosis. In a multivariable analysis, the mean normalized fluid-attenuated inversion recovery signal intensity on normal-appearing white matter was positively associated with leukoaraiosis volume and age (B = 0.025 for each leukoaraiosis quartile increase; 95% confidence interval 0.019-0.030). This association was found similarly across normal-appearing white matter strata. Voxel maps of the mean normalized fluid-attenuated inversion recovery signal intensity on normal-appearing white matter showed an increase in signal intensity that was not adjacent to leukoaraiosis regions. Our results show that normal-appearing white matter exhibits subtle signal intensity changes on fluid-attenuated inversion recovery imaging that are related to leukoaraiosis burden. These results suggest that diffuse free-water accumulation is likely related to the aetiopathogenic processes underlying the development of white matter damage related to small-vessel disease.

Early Intubation in Endovascular Therapy for Basilar Artery Occlusion: A Post Hoc Analysis of the BASICS Trial

BACKGROUND

The optimal anesthetic management for endovascular therapy (EVT) in patients with posterior circulation stroke remains unclear. Our objective was to investigate the impact of early intubation in patients enrolled in the BASICS trial (Basilar Artery International Cooperation Study).

METHODS

BASICS was a multicenter, randomized, controlled trial that compared the efficacy of EVT compared with the best medical care alone in patients with basilar artery occlusion. In this post hoc analysis, early intubation within the first 24 hours of the estimated time of basilar artery occlusion was examined as an additional covariate using regression modeling. We estimated the adjusted relative risks (RRs) for favorable outcomes, defined as modified Rankin Scale scores of 0 to 3 at 90 days. An adjusted common odds ratio was estimated for a shift in the distribution of modified Rankin Scale scores at 90 days.

RESULTS

Of 300 patients in BASICS, 289 patients were eligible for analysis (151 in the EVT group and 138 in the best medical care group). compared with medical care alone, EVT was related to a higher risk of early intubation (RR, 1.29 [95% CI, 1.09-1.53]; P<0.01), and early intubation was negatively associated with favorable outcome (RR, 0.61 [95% CI, 0.45-0.84]; P=0.002). Whereas there was no overall treatment effect of EVT on favorable outcome (RR, 1.22 [95% CI, 0.95-1.55]; P=0.121), EVT was associated with favorable outcome (RR, 1.34 [95% CI, 1.05-1.71]; P=0.018) and a shift toward lower modified Rankin Scale scores (adjusted common odds ratio, 1.63 [95% CI, 1.04-2.57]; P=0.033) if adjusted for early intubation.

CONCLUSIONS

In this post hoc analysis of the neutral BASICS trial, early intubation was linked to unfavorable outcomes, which might mitigate a potential benefit from EVT by indirect effects due to an increased risk of early intubation. This relationship may be considered when assessing the efficacy of EVT in patients with basilar artery occlusion in future trials.

The third Intensive Care Bundle with Blood Pressure Reduction in Acute Cerebral Haemorrhage Trial (INTERACT3): an international, stepped wedge cluster randomised controlled trial

BACKGROUND

Early control of elevated blood pressure is the most promising treatment for acute intracerebral haemorrhage. We aimed to establish whether implementing a goal-directed care bundle incorporating protocols for early intensive blood pressure lowering and management algorithms for hyperglycaemia, pyrexia, and abnormal anticoagulation, implemented in a hospital setting, could improve outcomes for patients with acute spontaneous intracerebral haemorrhage.

METHODS

We performed a pragmatic, international, multicentre, blinded endpoint, stepped wedge cluster randomised controlled trial at hospitals in nine low-income and middle-income countries (Brazil, China, India, Mexico, Nigeria, Pakistan, Peru, Sri Lanka, and Viet Nam) and one high-income country (Chile). Hospitals were eligible if they had no or inconsistent relevant, disease-specific protocols, and were willing to implement the care bundle to consecutive patients (aged ≥18 years) with imaging-confirmed spontaneous intracerebral haemorrhage presenting within 6 h of the onset of symptoms, had a local champion, and could provide the required study data. Hospitals were centrally randomly allocated using permuted blocks to three sequences of implementation, stratified by country and the projected number of patients to be recruited over the 12 months of the study period. These sequences had four periods that dictated the order in which the hospitals were to switch from the control usual care procedure to the intervention implementation of the care bundle procedure to different clusters of patients in a stepped manner. To avoid contamination, details of the intervention, sequence, and allocation periods were concealed from sites until they had completed the usual care control periods. The care bundle protocol included the early intensive lowering of systolic blood pressure (target <140 mm Hg), strict glucose control (target 6·1-7·8 mmol/L in those without diabetes and 7·8-10·0 mmol/L in those with diabetes), antipyrexia treatment (target body temperature ≤37·5°C), and rapid reversal of warfarin-related anticoagulation (target international normalised ratio <1·5) within 1 h of treatment, in patients where these variables were abnormal. Analyses were performed according to a modified intention-to-treat population with available outcome data (ie, excluding sites that withdrew during the study). The primary outcome was functional recovery, measured with the modified Rankin scale (mRS; range 0 [no symptoms] to 6 [death]) at 6 months by masked research staff, analysed using proportional ordinal logistic regression to assess the distribution in scores on the mRS, with adjustments for cluster (hospital site), group assignment of cluster per period, and time (6-month periods from Dec 12, 2017). This trial is registered at Clinicaltrials.gov (NCT03209258) and the Chinese Clinical Trial Registry (ChiCTR-IOC-17011787) and is completed.

FINDINGS

Between May 27, 2017, and July 8, 2021, 206 hospitals were assessed for eligibility, of which 144 hospitals in ten countries agreed to join and were randomly assigned in the trial, but 22 hospitals withdrew before starting to enrol patients and another hospital was withdrawn and their data on enrolled patients was deleted because regulatory approval was not obtained. Between Dec 12, 2017, and Dec 31, 2021, 10 857 patients were screened but 3821 were excluded. Overall, the modified intention-to-treat population included 7036 patients enrolled at 121 hospitals, with 3221 assigned to the care bundle group and 3815 to the usual care group, with primary outcome data available in 2892 patients in the care bundle group and 3363 patients in the usual care group. The likelihood of a poor functional outcome was lower in the care bundle group (common odds ratio 0·86; 95% CI 0·76-0·97; p=0·015). The favourable shift in mRS scores in the care bundle group was generally consistent across a range of sensitivity analyses that included additional adjustments for country and patient variables (0·84; 0·73-0·97; p=0·017), and with different approaches to the use of multiple imputations for missing data. Patients in the care bundle group had fewer serious adverse events than those in the usual care group (16·0% vs 20·1%; p=0·0098).

INTERPRETATION

Implementation of a care bundle protocol for intensive blood pressure lowering and other management algorithms for physiological control within several hours of the onset of symptoms resulted in improved functional outcome for patients with acute intracerebral haemorrhage. Hospitals should incorporate this approach into clinical practice as part of active management for this serious condition.

FUNDING

Joint Global Health Trials scheme from the Department of Health and Social Care, the Foreign, Commonwealth & Development Office, and the Medical Research Council and Wellcome Trust; West China Hospital; the National Health and Medical Research Council of Australia; Sichuan Credit Pharmaceutic and Takeda China.

Effects of intensive blood pressure lowering on cerebral ischaemia in thrombolysed patients: insights from the ENCHANTED trial

Background

Intensive blood pressure lowering may adversely affect evolving cerebral ischaemia. We aimed to determine whether intensive blood pressure lowering altered the size of cerebral infarction in the 2196 patients who participated in the Enhanced Control of Hypertension and Thrombolysis Stroke Study, an international randomised controlled trial of intensive (systolic target 130-140 mm Hg within 1 h; maintained for 72 h) or guideline-recommended (systolic target <180 mm Hg) blood pressure management in patients with hypertension (systolic blood pressure >150 mm Hg) after thrombolysis treatment for acute ischaemic stroke between March 3, 2012 and April 30, 2018.

Methods

All available brain imaging were analysed centrally by expert readers. Log-linear regression was used to determine the effects of intensive blood pressure lowering on the size of cerebral infarction, with adjustment for potential confounders. The primary analysis pertained to follow-up computerised tomography (CT) scans done between 24 and 36 h. Sensitivity analysis were undertaken in patients with only a follow-up magnetic resonance imaging (MRI) and either MRI or CT at 24-36 h, and in patients with any brain imaging done at any time during follow-up. This trial is registered with ClinicalTrials.gov, number NCT01422616.

Findings

There were 1477 (67.3%) patients (mean age 67.7 [12.1] y; male 60%, Asian 65%) with available follow-up brain imaging for analysis, including 635 patients with a CT done at 24-36 h. Mean achieved systolic blood pressures over 1-24 h were 141 mm Hg and 149 mm Hg in the intensive group and guideline group, respectively. There was no effect of intensive blood pressure lowering on the median size (ml) of cerebral infarction on follow-up CT at 24-36 h (0.3 [IQR 0.0-16.6] in the intensive group and 0.9 [0.0-12.5] in the guideline group; log Δmean -0.17, 95% CI -0.78 to 0.43). The results were consistent in sensitivity and subgroup analyses.

Interpretation

Intensive blood pressure lowering treatment to a systolic target <140 mm Hg within several hours after the onset of symptoms may not increase the size of cerebral infarction in patients who receive thrombolysis treatment for acute ischaemic stroke of mild to moderate neurological severity.

Funding

National Health and Medical Research Council of Australia; UK Stroke Association; UK Dementia Research Institute; Ministry of Health and the National Council for Scientific and Technological Development of Brazil; Ministry for Health, Welfare, and Family Affairs of South Korea; Takeda.

Abstract WMP52: Markers Of Endothelial Glycocalyx Damage In Patients Withvascular Cognitive Impairment Associated With Cerebral Small Vessel Disease

Introduction: Cerebral small vessel disease (cSVD) involves a myriad of pathogenic mechanisms affecting small vessels of the brain, leading to a significant impact on motor and cognitive functions, and it is the main cause of Vascular cognitive impairment (VCI). The endothelial glycocalyx (EG), the layer lining the vascular endothelium, has a pivotal player in maintaining the proper function of neurovascular unit, and its degradation may be involved in VCI due to cSVD.

Objectives: to investigate the relationship between markers of EG damage and VCI related to cSVD.

Methods: Cross-sectional study based on clinical data and serum samples for the quantification of EG damage markers (syndecan-1, hyaluran) of VCI related to cSVD patients and of a control group derived from a dataset of healthy workers from the same institution. We used an automatic logarithm for segmentation and volumetric evaluation of white matter lesions on brain MRI of the patients. Logistic regression models and c-statistics were used to identify the independent variables related to VCI and investigate the accuracy of syndecan-1 to detect VCI. We studied the association of thebiomarkers and MoCA scores, index of independence in activities of daily living and whitematter lesion burden respectively.

Results: Between July 2019 and March 2020, we studied 22 patients with VCI associated with cSVD and compared them with a dataset of 22 healthy workers from the same institution. Patients with VCI were older, had a higher prevalence of diabetesmellitus and hypertension, had a worse index of independence for daily activities, and higherlevels of syndecan-1 (78,4 vs 24; p < 0,01). There was no difference in hyaluran levels between both groups. In multivariate analysis, only age (OR 1,35;CI 1,04 - 1,76; p = 0,02) and syndecan-1 levels (OR 1,08;CI 1,01 - 1,15;p = 0,01) related to VCI. The ROC curve ofsyndecan-1 levels to predict VCI had a area under de curve of 0,78 (CI 0,64 - 0,92) and there was a correlation between syndecan-1 levels and MoCA scores (rho = - 0,34;p = 0,02). There were no correlations between syndecan-1 and hyaluran levels and index of independence and white matter lesion burden respectively.

Conclusions: Syndecan-1, but not hyaluran, is a potential biomarker for VCI associated with cSVD.

Peak width of skeletonized mean diffusivity in cerebral amyloid angiopathy: Spatial signature, cognitive, and neuroimaging associations

Background

Peak width of skeletonized mean diffusivity (PSMD) is a promising diffusion tensor imaging (DTI) marker that shows consistent and strong cognitive associations in the context of different cerebral small vessel diseases (cSVD).

Purpose

Investigate whether PSMD (1) is higher in patients with Cerebral Amyloid Angiopathy (CAA) than those with arteriolosclerosis; (2) can capture the anteroposterior distribution of CAA-related abnormalities; (3) shows similar neuroimaging and cognitive associations in comparison to other classical DTI markers, such as average mean diffusivity (MD) and fractional anisotropy (FA).

Materials and methods

We analyzed cross-sectional neuroimaging and neuropsychological data from 90 non-demented memory-clinic subjects from a single center. Based on MRI findings, we classified them into probable-CAA (those that fulfilled the modified Boston criteria), subjects with MRI markers of cSVD not attributable to CAA (presumed arteriolosclerosis; cSVD), and subjects without evidence of cSVD on MRI (non-cSVD). We compared total and lobe-specific (frontal and occipital) DTI metrics values across the groups. We used linear regression models to investigate how PSMD, MD, and FA correlate with conventional neuroimaging markers of cSVD and cognitive scores in CAA.

Results

PSMD was comparable in probable-CAA (median 4.06 × 10^–4 mm²/s) and cSVD (4.07 × 10^–4 mm²/s) patients, but higher than in non-cSVD (3.30 × 10^–4 mm²/s; p < 0.001) subjects. Occipital-frontal PSMD gradients were higher in probable-CAA patients, and we observed a significant interaction between diagnosis and region on PSMD values [F(2, 87) = 3.887, p = 0.024]. PSMD was mainly associated with white matter hyperintensity volume, whereas MD and FA were also associated with other markers, especially with the burden of perivascular spaces. PSMD correlated with worse executive function (β = −0.581, p < 0.001) and processing speed (β = −0.463, p = 0.003), explaining more variance than other MRI markers. MD and FA were not associated with performance in any cognitive domain.

Conclusion

PSMD is a promising biomarker of cognitive impairment in CAA that outperforms other conventional and DTI-based neuroimaging markers. Although global PSMD is similarly increased in different forms of cSVD, PSMD’s spatial variations could potentially provide insights into the predominant type of underlying microvascular pathology.

White Matter Hyperintensities and Poststroke Apathy: A Fully Automated MRI Segmentation Study

INTRODUCTION

Poststroke apathy (PSA) is a common neuropsychiatric disorder that may affect up to 30% of stroke patients. Despite the difficulties of investigating this condition (overlapping with depression, heterogeneity of diagnostic criteria, a small number of studies), some recent diffusion tensor imaging studies have suggested that widespread microstructural white matter (WM) disruption plays a key role in the development of PSA. Therefore, we intended to investigate this hypothesis by evaluating the relationship between WM hyperintensities (WMH) and apathy in patients with cerebrovascular disease.

METHODS

We studied patients with apathy (n = 7), depression (n = 13), comorbid apathy and depression (n = 13), and controls (n = 20), and we investigated the variables associated with the volume of WMH measured by an automated brain MRI segmentation software.

RESULTS

The overall prevalence of PSA was 37.7% (pure and comorbid). Patients with apathy presented a higher volume of WMH in comparison to controls. Mini-Mental State Examination (MMSE), NPI-A, and the number of cerebral microbleeds were the only variables associated with WMH. Conversely, NPI-D did not correlate to WMH.

DISCUSSION/CONCLUSION

This is an exploratory study that supports the view of PSA as a distinct syndrome from PSD mediated mainly by diffuse white matter hyperintensities, which suggests that WM disruption is an important pathway to the development of apathy in stroke patients.

Contrast-agent-free state-of-the-art MRI on cerebral small vessel disease-part 1. ASL, IVIM, and CVR

Cerebral small vessel disease (cSVD), a common cause of stroke and dementia, is traditionally considered the small vessel equivalent of large artery occlusion or rupture that leads to cortical and subcortical brain damage. Microvessel endothelial dysfunction can also contribute to it. Brain imaging, including MRI, is useful to show the presence of lesions of several types, although the association between conventional MRI measures and clinical features of cSVD is not always concordant. We assessed the additional contribution of contrast-agent-free, state-of-the-art MRI techniques such as arterial spin labeling (ASL), diffusion tensor imaging, functional MRI, and intravoxel incoherent motion (IVIM) applied to cSVD in the existing literature. We performed a review following the PICO Worksheet and Search Strategy, including original papers in English, published between 2000 and 2022. For each MRI method, we extracted information about their contributions, in addition to those established with traditional MRI methods and related information about the origins, pathology, markers, and clinical outcomes in cSVD. This paper presents the first part of the review, which includes 37 studies focusing on ASL, IVIM, and cerebrovascular reactivity (CVR) measures. In general, they have shown that, in addition to white matter hyperintensities, alterations in other neuroimaging parameters such as blood flow and CVR also indicate the presence of cSVD. Such quantitative parameters were also related to cSVD risk factors. Therefore, they are promising, noninvasive tools to explore questions that have not yet been clarified about this clinical condition. However, protocol standardization is essential to increase their clinical use.

Contrast agent-free state-of-the-art magnetic resonance imaging on cerebral small vessel disease - Part 2: Diffusion tensor imaging and functional magnetic resonance imaging

Cerebral small vessel disease (cSVD) has been widely studied using conventional magnetic resonance imaging (MRI) methods, although the association between MRI findings and clinical features of cSVD is not always concordant. We assessed the additional contribution of contrast agent-free, state-of-the-art MRI techniques, particularly diffusion tensor imaging (DTI) and functional magnetic resonance imaging (fMRI), to understand brain damage and structural and functional connectivity impairment related to cSVD. We performed a review following the PICOS worksheet and Search Strategy, including 152 original papers in English, published from 2000 to 2022. For each MRI method, we extracted information about their contributions regarding the origins, pathology, markers, and clinical outcomes in cSVD. In general, DTI studies have shown that changes in mean, radial, and axial diffusivity measures are related to the presence of cSVD. In addition to the classical deficit in executive functions and processing speed, fMRI studies indicate connectivity dysfunctions in other domains, such as sensorimotor, memory, and attention. Neuroimaging metrics have been correlated with the diagnosis, prognosis, and rehabilitation of patients with cSVD. In short, the application of contrast agent-free, state-of-the-art MRI techniques has provided a complete picture of cSVD markers and tools to explore questions that have not yet been clarified about this clinical condition. Longitudinal studies are desirable to look for causal relationships between image biomarkers and clinical outcomes.

Embolic Stroke of Undetermined Source: Approaches in Risk Stratification for Cardioembolism

Ischemic stroke is a leading cause of morbidity and mortality worldwide. Embolic stroke of undetermined source has been recently proposed to categorize nonlacunar ischemic strokes without confirmed etiology after adequate investigation with a likely embolic stroke mechanism. A strategy of empirical anticoagulation for embolic stroke of undetermined source patients is attractive but may only be beneficial in a select subset of patients. Strategies which would help identify the subset of embolic stroke of undetermined source patients most likely to have cardioembolic origin of stroke, and hence benefit from anticoagulation, are needed. This article will review current evidence which may be useful in the development of a risk stratification approach based on arrhythmia monitoring, cardiac imaging, and clinical risk stratification. This approach may be beneficial in clinical practice in improving patient outcomes and reducing stroke recurrence in this population; however, further work is required with active trials underway.

Associations of Early Systolic Blood Pressure Control and Outcome After Thrombolysis-Eligible Acute Ischemic Stroke: Results From the ENCHANTED Study

BACKGROUND AND PURPOSE

In thrombolysis-eligible patients with acute ischemic stroke, there is uncertainty over the most appropriate systolic blood pressure (SBP) lowering profile that provides an optimal balance of potential benefit (functional recovery) and harm (intracranial hemorrhage). We aimed to determine relationships of SBP parameters and outcomes in thrombolyzed acute ischemic stroke patients.

METHODS

Post hoc analyzes of the ENCHANTED (Enhanced Control of Hypertension and Thrombolysis Stroke Study), a partial-factorial trial of thrombolysis-eligible and treated acute ischemic stroke patients with high SBP (150-180 mm Hg) assigned to low-dose (0.6 mg/kg) or standard-dose (0.9 mg/kg) alteplase and intensive (target SBP, 130-140 mm Hg) or guideline-recommended (target SBP <180 mm Hg) treatment. All patients were followed up for functional status and serious adverse events to 90 days. Logistic regression models were used to analyze 3 SBP summary measures postrandomization: attained (mean), variability (SD) in 1-24 hours, and magnitude of reduction in 1 hour. The primary outcome was a favorable shift on the modified Rankin Scale. The key safety outcome was any intracranial hemorrhage.

RESULTS

Among 4511 included participants (mean age 67 years, 38% female, 65% Asian) lower attained SBP and smaller SBP variability were associated with favorable shift on the modified Rankin Scale (per 10 mm Hg increase: odds ratio, 0.76 [95% CI, 0.71-0.82], P<0.001 and 0.86 [95% CI, 0.76-0.98], P=0.025) respectively, but not for magnitude of SBP reduction (0.98, [0.93-1.04], P=0.564). Odds of intracranial hemorrhage was associated with higher attained SBP and greater SBP variability (1.18 [1.06-1.31], P=0.002 and 1.34 [1.11-1.62], P=0.002) but not with magnitude of SBP reduction (1.05 [0.98-1.14], P=0.184).

CONCLUSIONS

Attaining early and consistent low levels in SBP <140 mm Hg, even as low as 110 to 120 mm Hg, over 24 hours is associated with better outcomes in thrombolyzed acute ischemic stroke patients.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT01422616.

Conquering stroke epidemiological statistics in Brazil an innovative initiative from the Brazilian Society of Cardiology

Background

Stroke has been the second major cause of death in Brazil in the last decades. A better understanding on epidemiological statistics as well as on the diseases burden is crucial for enabling stakeholders to better tackle the disease.

Purpose

This project aims to continuously monitor and evaluate the data sources on heart disease and stroke in Brazil to provide the most up-to-date information on the epidemiology of these diseases to Brazilian society annually.

Methods

This initiative is based on the Heart Disease & Stroke Statistics Update methodology of the American Heart Association, with the support of the Brazilian Society of Cardiology, the Global Burden of Diseases Brazil network and an international committee. The project incorporates official statistics provided by the Brazilian Ministry of Health and other government agencies, as well as data generated by other sources and scientific studies on heart disease, stroke, and other CVD, including GBD/IHME data.

Results

The age-standardized prevalence rates per 100.000 for ischemic stroke in 1990 was 1327,6 (1151.2 to 1516) and 870.1 (761.1 to 992.8) in 2019 representing a percent change of −34.5 (−36.7 to −0.3). The age-standardized prevalence rates for intracerebral hemorrhage in 1990 was 507.5 (438.9 to584.1) and 315.9 (275 to 361.4) in 2019 representing a percent change of −37.7 (−40.5 to −0.3). The age-standardized incidence rates for stroke in 1990 was 224.6 (201.6 to 251.8) and 127 (113.8 to 142.1) in 2019 representing a percent change of −43.5 (−44.7 to −0.4). the age-standardized mortality rates for stroke in 1990 was 137.8 (127.8 to 144) and 58.1 (52.6 to 61.8) in 2019 representing a percent change of −57.8 (−60.4 to −0.6). The age-standardized DALY rates for stroke in 1990 was 2959 (2829.6 to 3063) and 1219.6 (1142 to 1285.5) in 2019 representing a percent change of −58.8 (−61 to −0.6).

Conclusion

This project represents a fundamental step on a better understanding on the stroke epidemiology in Brazil. While we observed a significant decrease in mortality rates from 1990 to 2019, we also raise a concern on a possible shift for a plateau curve or even increased rates in the next years.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): Brazilian Society of Cardiology

Oxygen desaturation and adverse outcomes in acute stroke: Secondary analysis of the HeadPoST study

OBJECTIVE

Uncertainty exists over the prognostic significance of low arterial oxygen saturation (SaO₂) in acute stroke. We aimed to determine the strength of association of SaO₂ and adverse outcomes among participants of the international Head Positioning in acute Stroke Trial (HeadPoST).

METHODS

Post-hoc analyzes of HeadPoST, a pragmatic cluster-crossover randomized trial of lying flat versus sitting up head positioning in 11,093 patients (age ≥18 years) with acute stroke at 114 hospitals in 9 countries during 2015-2016. Associations of the lowest recorded SaO₂ level, as a continuous measure and as a cut-point for desaturation (SaO₂ <93%), in the first 24 h and clinical outcomes of death or dependency (modified Rankin scale [mRS] scores 3-6) and any serious adverse event (SAE) at 90 days, were assessed in generalized linear mixed models adjusted for baseline and in-hospital management confounders.

RESULTS

There was an inverse J-shaped association between SaO₂ and death or dependency, with a nadir for optimal outcome at 96-97%. Patients with SaO₂ desaturation were older, and had greater neurological impairment, premorbid disability and cardiorespiratory disease. Desaturation was not clearly associated with death or dependency (adjusted odds ratio [aOR] 1.19, 95% confidence interval [CI] 0.95-1.48) but was with SAEs (aOR 1.34, 95% CI 1.07-1.68), without heterogeneity by head position, cardiac-respiratory comorbidity, or other pre-specified subgroups.

CONCLUSIONS

Any change in SaO₂ outside of 96-97% is associated with poorer outcome after acute stroke.

CLINICAL TRIAL REGISTRATION

HeadPoST is registered at ClinicalTrials.gov (NCT02162017).

Endovascular Therapy for Stroke Due to Basilar-Artery Occlusion

BACKGROUND

The effectiveness of endovascular therapy in patients with stroke caused by basilar-artery occlusion has not been well studied.

METHODS

We randomly assigned patients within 6 hours after the estimated time of onset of a stroke due to basilar-artery occlusion, in a 1:1 ratio, to receive endovascular therapy or standard medical care. The primary outcome was a favorable functional outcome, defined as a score of 0 to 3 on the modified Rankin scale (range, 0 to 6, with 0 indicating no disability, 3 indicating moderate disability, and 6 indicating death) at 90 days. The primary safety outcomes were symptomatic intracranial hemorrhage within 3 days after the initiation of treatment and mortality at 90 days.

RESULTS

A total of 300 patients were enrolled (154 in the endovascular therapy group and 146 in the medical care group). Intravenous thrombolysis was used in 78.6% of the patients in the endovascular group and in 79.5% of those in the medical group. Endovascular treatment was initiated at a median of 4.4 hours after stroke onset. A favorable functional outcome occurred in 68 of 154 patients (44.2%) in the endovascular group and 55 of 146 patients (37.7%) in the medical care group (risk ratio, 1.18; 95% confidence interval [CI], 0.92 to 1.50). Symptomatic intracranial hemorrhage occurred in 4.5% of the patients after endovascular therapy and in 0.7% of those after medical therapy (risk ratio, 6.9; 95% CI, 0.9 to 53.0); mortality at 90 days was 38.3% and 43.2%, respectively (risk ratio, 0.87; 95% CI, 0.68 to 1.12).

CONCLUSIONS

Among patients with stroke from basilar-artery occlusion, endovascular therapy and medical therapy did not differ significantly with respect to a favorable functional outcome, but, as reflected by the wide confidence interval for the primary outcome, the results of this trial may not exclude a substantial benefit of endovascular therapy. Larger trials are needed to determine the efficacy and safety of endovascular therapy for basilar-artery occlusion. (Funded by the Dutch Heart Foundation and others; BASICS ClinicalTrials.gov number, NCT01717755; Netherlands Trial Register number, NL2500.).

Decline in subarachnoid haemorrhage volumes associated with the first wave of the COVID-19 pandemic

Background

During the COVID-19 pandemic, decreased volumes of stroke admissions and mechanical thrombectomy were reported. The study’s objective was to examine whether subarachnoid haemorrhage (SAH) hospitalisations and ruptured aneurysm coiling interventions demonstrated similar declines.

Methods

We conducted a cross-sectional, retrospective, observational study across 6 continents, 37 countries and 140 comprehensive stroke centres. Patients with the diagnosis of SAH, aneurysmal SAH, ruptured aneurysm coiling interventions and COVID-19 were identified by prospective aneurysm databases or by International Classification of Diseases, 10th Revision, codes. The 3-month cumulative volume, monthly volumes for SAH hospitalisations and ruptured aneurysm coiling procedures were compared for the period before (1 year and immediately before) and during the pandemic, defined as 1 March–31 May 2020. The prior 1-year control period (1 March–31 May 2019) was obtained to account for seasonal variation.

Findings

There was a significant decline in SAH hospitalisations, with 2044 admissions in the 3 months immediately before and 1585 admissions during the pandemic, representing a relative decline of 22.5% (95% CI −24.3% to −20.7%, p<0.0001). Embolisation of ruptured aneurysms declined with 1170–1035 procedures, respectively, representing an 11.5% (95%CI −13.5% to −9.8%, p=0.002) relative drop. Subgroup analysis was noted for aneurysmal SAH hospitalisation decline from 834 to 626 hospitalisations, a 24.9% relative decline (95% CI −28.0% to −22.1%, p<0.0001). A relative increase in ruptured aneurysm coiling was noted in low coiling volume hospitals of 41.1% (95% CI 32.3% to 50.6%, p=0.008) despite a decrease in SAH admissions in this tertile.

Interpretation

There was a relative decrease in the volume of SAH hospitalisations, aneurysmal SAH hospitalisations and ruptured aneurysm embolisations during the COVID-19 pandemic. These findings in SAH are consistent with a decrease in other emergencies, such as stroke and myocardial infarction.

Low blood pressure and adverse outcomes in acute stroke: HeadPoST study explanations

OBJECTIVE

As uncertainties exist over underlying causes, we aimed to define the characteristics and prognostic significance of low blood pressure (BP) early after the onset of acute stroke.

METHODS

Post hoc analyzes of the international Head Positioning in acute Stroke Trial (HeadPoST), a pragmatic cluster-crossover randomized trial of lying flat versus sitting up in stroke patients from nine countries during 2015-2016. Associations of baseline BP and death or dependency [modified Rankin scale (mRS) scores 3-6] and serious adverse events (SAEs) at 90 days were assessed in generalized linear mixed models with adjustment for multiple confounders. SBP and DBP was analysed as continuous measures fitted with a cubic spline, and as categorical measures with low (<10th percentile) and high (≥140 and ≥90 mmHg, respectively) levels compared with a normal range (≥10th percentile; 120-139 and 70-89 mmHg, respectively).

RESULTS

Among 11 083 patients (mean age 68 years, 39.9% women) with baseline BP values, 7.2 and 11.7% had low SBP (<120 mmHg) and DBP (<70 mmHg), respectively. Patients with low SBP were more likely to have preexisting cardiac and ischemic stroke and functional impairment, and to present earlier with more severe neurological impairment than other patients. Nonlinear 'J-shaped' relationships of BP and poor outcome were apparent: compared with normal SBP, those with low SBP had worse functional outcome (adjusted odds ratio 1.27, 95% confidence interval 1.02-1.58) and more SAEs, particularly cardiac events, with adjustment for potential confounders to minimize reverse causation. The findings were consistent for DBP and were stronger for ischemic rather than hemorrhagic stroke.

CONCLUSION

The prognostic significance of low BP on poor outcomes in acute stroke was not explained by reverse causality from preexisting cardiovascular disease, and propensity towards greater neurological deficits and cardiac events. These findings provide support for the hypothesis that low BP exacerbates cardiac and cerebral ischemia in acute ischemic stroke.

Prognostic significance of early urinary catheterization after acute stroke: Secondary analyses of the international HeadPoST trial

BACKGROUND

An indwelling urinary catheter (IUC) is often inserted to manage bladder dysfunction, but its impact on prognosis is uncertain. We aimed to determine the association of IUC use on clinical outcomes after acute stroke in the international, multi-center, cluster crossover, Head Positioning in Acute Stroke Trial (HeadPoST).

METHODS

Data were analyzed on HeadPoST participants (n = 11,093) randomly allocated to the lying-flat or sitting-up head position. Binomial, logistic regression, hierarchical mixed models were used to determine associations of early insertion of IUC within seven days post-randomization and outcomes of death or disability (defined as "poor outcome," scores 3-6 on the modified Rankin scale) and any urinary tract infection at 90 days with adjustment of baseline and post-randomization management covariates.

RESULTS

Overall, 1167 (12%) patients had an IUC, but the frequency and duration of use varied widely across patients in different regions. IUC use was more frequent in older patients, and those with vascular comorbidity, greater initial neurological impairment (on the National Institutes of Health Stroke Scale), and intracerebral hemorrhage as the underlying stroke type. IUC use was independently associated with poor outcome (adjusted odds ratio (aOR): 1.40, 95% confidence interval (CI): 1.13-1.74), but not with urinary tract infection after adjustment for antibiotic treatment and stroke severity at hospital separation (aOR: 1.13, 95% CI: 0.59-2.18). The number exposed to IUC for poor outcome was 13.

CONCLUSIONS

IUC use is associated with a poor outcome after acute stroke. Further studies are required to inform appropriate use of IUC.

Abstract WP9: Impact of Sex Differences on the Treatment Effect of Mechanical Thrombectomy: A Subgroup Analysis of the RESILIENT Trial

Background: Despite evidence supporting the overall efficacy of mechanical thrombectomy (MT) in acute ischemic stroke (AIS) due to large vessel occlusion (LVO) of the anterior circulation, it is unclear whether the treatment effect of MT differs by sex in different populations. We assessed the impact of sex differences in the treatment effect of MT in the RESILIENT trial.

Methods: RESILIENT was a prospective, multicenter, randomized phase III trial that was designed to assess the safety, efficacy, and cost-effectiveness of mechanical thrombectomy as compared to medical treatment alone in patients treated under the less than ideal conditions typically found in the public healthcare system of a developing country.

Results: Among 221 patients enrolled in the trial, 104 (47,1%) were female. Baseline characteristics were well balanced between sexes, except for a higher prevalence of hypertension (76% vs. 57.4%; p=0.004) and diabetes (34.3% vs. 21.7%; p=0.039) and a lower frequency of alcohol abuse (4% vs. 28.9%; p=0.001) in females. After adjustment for baseline characteristics, we found a significant interaction (p=0.026) between sex and the effect of MT with a lower efficacy of MT for functional independency at 90 days among women (aOR=1.13;95%CI:0.42-3.02) compared to men (aOR=4.78; 95%CI:1.88-12.15).

Conclusions: In our study population of patients with AIS caused by LVO of the anterior circulation, women were less likely to benefit from MT than men. Further studies are necessary to investigate these findings.

Corneal Reflex Testing in the Evaluation of a Comatose Patient: An Ode to Precise Semiology and Examination Skills

BACKGROUND/OBJECTIVE

The corneal reflex assesses the integrity of the trigeminal and facial cranial nerves. This brainstem reflex is fundamental in neuroprognostication after cardiac arrest and in brain death determination. We sought to investigate corneal reflex testing methods among neurologists and general critical care providers in the context of neuroprognostication following cardiac arrest.

METHODS

This is an international cross-sectional study disseminated to members of the Neurocritical Care Society, Society of Critical Care Medicine, and American Academy of Neurology. We utilized an open Web-based survey (Qualtrics^®, Provo, UT, USA) to disseminate 26 questions regarding neuroprognostication practices following cardiac arrest, in which 3 questions pertained to corneal reflex testing. Descriptive statistical measures were used, and subgroup analyses performed between neurologists and non-neurologists. Questions were not mandatory; therefore, the percentages were relative to the number of respondents for each question.

RESULTS

There were 959 respondents in total. Physicians comprised 85.1% of practitioners (762 out of 895), of which 55% (419) identified themselves as non-neurologists and 45% (343) as neurologists. Among physicians, 85.9% (608 out of 708) deemed corneal reflex relevant for prognostication following cardiac arrest (neurologists 84.4% versus non-neurologists 87.0%). A variety of techniques were employed for corneal reflex testing, the most common being "light cotton touch" (59.2%), followed by "cotton-tipped applicator with pressure" (23.9%), "saline or water squirt" (15.9%), and "puff of air" (1.0%). There were no significant differences in the methods for testing between neurologists and non-neurologists (p = 0.52). The location of stimulus application was variable, and 26.1% of physicians (148/567) apply the stimulus on the temporal conjunctiva rather than on the cornea itself.

CONCLUSIONS

Corneal reflex testing remains a cornerstone of the coma exam and is commonly used in neuroprognostication of unconscious cardiac arrest survivors and in brain death determination. A wide variability of techniques is noted among practitioners, including some that may provide suboptimal stimulation of corneal nerve endings. Imprecise testing in this setting may lead to inaccuracies in critical settings, which carries significant consequences such as guiding decisions of care limitations, misdiagnosis of brain death, and loss of public trust.

Fractional Anisotropy of Thalamic Nuclei Is Associated With Verticality Misperception After Extra-Thalamic Stroke

Verticality misperception after stroke is a frequent neurological deficit that leads to postural imbalance and a higher risk of falls. The posterior thalamic nuclei are described to be involved with verticality perception, but it is unknown if extra-thalamic lesions can have the same effect via diaschisis and degeneration of thalamic nuclei. We investigated the relationship between thalamic fractional anisotropy (FA, a proxy of structural integrity), and verticality perception, in patients after stroke with diverse encephalic extra-thalamic lesions. We included 11 first time post-stroke patients with extra-thalamic primary lesions, and compared their region-based FA to a group of 25 age-matched healthy controls. For the patient sample, correlation and regression analyses evaluated the relationship between thalamic nuclei FA and error of postural vertical (PV) and haptic vertical (HV) in the roll (PVroll/HVroll) and pitch planes (PVpitch/HVpitch). Relative to controls, patients showed decreased FA of anterior, ventral anterior, ventral posterior lateral, dorsal, and pulvinar thalamic nuclei, despite the primary lesions being extra-thalamic. We found a significant correlation between HVroll, and FA in the anterior and dorsal nuclei, and PVroll with FA in the anterior nucleus. FA in the anterior, ventral anterior, ventral posterior lateral, dorsal and pulvinar nuclei predicted PV, and FA in the ventral anterior, ventral posterior lateral and dorsal nuclei predicted HV. While prior studies indicate that primary lesions of the thalamus can result in verticality misperception, here we present evidence supporting that secondary degeneration of thalamic nuclei via diaschisis can also be associated with verticality misperception after stroke.

Dysphagia screening and risks of pneumonia and adverse outcomes after acute stroke: An international multicenter study

BACKGROUND

Dysphagia is associated with aspiration pneumonia after stroke. Data are limited on the influences of dysphagia screen and assessment in clinical practice.

AIMS

To determine associations between a "brief" screen and "detailed" assessment of dysphagia on clinical outcomes in acute stroke patients.

METHODS

A prospective cohort study analyzed retrospectively using data from a multicenter, cluster cross-over, randomized controlled trial (Head Positioning in Acute Stroke Trial [HeadPoST]) from 114 hospitals in nine countries. HeadPoST included 11,093 acute stroke patients randomized to lying-flat or sitting-up head positioning. Herein, we report predefined secondary analyses of the association of dysphagia screening and assessment and clinical outcomes of pneumonia and death or disability (modified Rankin scale 3-6) at 90 days.

RESULTS

Overall, 8784 (79.2%) and 3917 (35.3%) patients were screened and assessed for dysphagia, respectively, but the frequency and timing for each varied widely across regions. Neither use of a screen nor an assessment for dysphagia was associated with the outcomes, but their results were compared to "screen-pass" patients, those who failed had higher risks of pneumonia (adjusted odds ratio [aOR] = 3.00, 95% confidence interval [CI] = 2.18-4.10) and death or disability (aOR = 1.66, 95% CI = 1.41-1.95). Similar results were evidence for the results of an assessment for dysphagia. Subsequent feeding restrictions were related to higher risk of pneumonia in patients failed dysphagia screen or assessment (aOR = 4.06, 95% CI = 1.72-9.54).

CONCLUSIONS

Failing a dysphagia screen is associated with increased risks of pneumonia and poor clinical outcome after acute stroke. Further studies concentrate on determining the effective subsequent feeding actions are needed to improve patient outcomes.

Applicability of ENCHANTED trial results to current acute ischemic stroke patients eligible for intravenous thrombolysis in England and Wales: Comparison with the Sentinel Stroke National Audit Programme registry

BACKGROUND

Randomized controlled trials provide high-level evidence, but the necessity to include selected patients may limit the generalisability of their results.

METHODS

Comparisons were made of baseline and outcome data between patients with acute ischemic stroke (AIS) recruited into the alteplase-dose arm of the international, multi-center, Enhanced Control of Hypertension and Thrombolysis Stroke study (ENCHANTED) in the United Kingdom (UK), and alteplase-treated AIS patients registered in the UK Sentinel Stroke National Audit Programme (SSNAP) registry, over the study period June 2012 to October 2015.

RESULTS

There were 770 AIS patients (41.2% female; mean age 72 years) included in ENCHANTED at sites in England and Wales, which was 19.5% of alteplase-treated AIS patients registered in the SSNAP registry. Trial participants were significantly older, had lower baseline neurological severity, less likely Asian, and had more premorbid symptoms, hypertension and atrial fibrillation. Although ENCHANTED participants had higher rates of symptomatic intracerebral hemorrhage than those in SSNAP, there were no differences in onset-to-treatment time, levels of disability (assessed by the modified Rankin scale) at hospital discharge, and mortality over 90 days between groups.

CONCLUSIONS

Despite the high level of participation, equipoise over the dose of alteplase among UK clinician investigators favored the inclusion of older, frailer, milder AIS patients in the ENCHANTED trial.

CLINICAL TRIAL REGISTRATION

Clinical Trial Registration-URL: http://www.clinicaltrials.gov . Unique identifier: NCT01422616.

Intensive blood pressure reduction with intravenous thrombolysis therapy for acute ischaemic stroke (ENCHANTED): an international, randomised, open-label, blinded-endpoint, phase 3 trial

BACKGROUND

Systolic blood pressure of more than 185 mm Hg is a contraindication to thrombolytic treatment with intravenous alteplase in patients with acute ischaemic stroke, but the target systolic blood pressure for optimal outcome is uncertain. We assessed intensive blood pressure lowering compared with guideline-recommended blood pressure lowering in patients treated with alteplase for acute ischaemic stroke.

METHODS

We did an international, partial-factorial, open-label, blinded-endpoint trial of thrombolysis-eligible patients (age ≥18 years) with acute ischaemic stroke and systolic blood pressure 150 mm Hg or more, who were screened at 110 sites in 15 countries. Eligible patients were randomly assigned (1:1, by means of a central, web-based program) within 6 h of stroke onset to receive intensive (target systolic blood pressure 130-140 mm Hg within 1 h) or guideline (target systolic blood pressure <180 mm Hg) blood pressure lowering treatment over 72 h. The primary outcome was functional status at 90 days measured by shift in modified Rankin scale scores, analysed with unadjusted ordinal logistic regression. The key safety outcome was any intracranial haemorrhage. Primary and safety outcome assessments were done in a blinded manner. Analyses were done on intention-to-treat basis. This trial is registered with ClinicalTrials.gov, number NCT01422616.

FINDINGS

Between March 3, 2012, and April 30, 2018, 2227 patients were randomly allocated to treatment groups. After exclusion of 31 patients because of missing consent or mistaken or duplicate randomisation, 2196 alteplase-eligible patients with acute ischaemic stroke were included: 1081 in the intensive group and 1115 in the guideline group, with 1466 (67·4%) administered a standard dose among the 2175 actually given intravenous alteplase. Median time from stroke onset to randomisation was 3·3 h (IQR 2·6-4·1). Mean systolic blood pressure over 24 h was 144·3 mm Hg (SD 10·2) in the intensive group and 149·8 mm Hg (12·0) in the guideline group (p<0·0001). Primary outcome data were available for 1072 patients in the intensive group and 1108 in the guideline group. Functional status (mRS score distribution) at 90 days did not differ between groups (unadjusted odds ratio [OR] 1·01, 95% CI 0·87-1·17, p=0·8702). Fewer patients in the intensive group (160 [14·8%] of 1081) than in the guideline group (209 [18·7%] of 1115) had any intracranial haemorrhage (OR 0·75, 0·60-0·94, p=0·0137). The number of patients with any serious adverse event did not differ significantly between the intensive group (210 [19·4%] of 1081) and the guideline group (245 [22·0%] of 1115; OR 0·86, 0·70-1·05, p=0·1412). There was no evidence of an interaction of intensive blood pressure lowering with dose (low vs standard) of alteplase with regard to the primary outcome.

INTERPRETATION

Although intensive blood pressure lowering is safe, the observed reduction in intracranial haemorrhage did not lead to improved clinical outcome compared with guideline treatment. These results might not support a major shift towards this treatment being applied in those receiving alteplase for mild-to-moderate acute ischaemic stroke. Further research is required to define the underlying mechanisms of benefit and harm resulting from early intensive blood pressure lowering in this patient group.

FUNDING

National Health and Medical Research Council of Australia; UK Stroke Association; Ministry of Health and the National Council for Scientific and Technological Development of Brazil; Ministry for Health, Welfare, and Family Affairs of South Korea; Takeda.

Abstract TP432: Dilated Optic Nerve Sheath Diameter by Trans-Orbital Ultrasound Predicts Mortality Among Patients With Acute Intracerebral Hemorrhage

Introduction: Supratentorial Intracerebral hemorrhage (ICH) main prognostic factors on admission are age, Glasgow coma scale (GCS), ICH volume and ventricular hemorrhage. Subsequent ICH expansion and associated elevated intracranial pressure (ICP) have also been linked to poorer outcomes. Dilatation of optic nerve sheath diameter (ONSD) by trans-orbital ultrasound examination is an increasingly recognized marker of elevated ICP. We sought to evaluate whether increased ONSD at hospital admission could be associated with mortality among patients with supratentorial ICH.

Methods: Prospective cohort of consecutive acute supratentorial ICH patients admitted to a tertiary stroke center. Exclusion criteria: 1) last well seen > 24 hours; 2) immediate surgical intervention indicated by neurosurgery team; 3) Secondary ICH (anticoagulants and antiplatelets were allowed); 4) previous optic nerve pathology precluding accurate ONSD measurements. Ultrasound assessment and CT performed within the first hour after admission. Primary outcome was 90-days mortality. Multivariate logistic regression, ROC curve and c-statistics was used to identify independent predictors of mortality.

Results: Between July 2014 and July 2017, 57 patients were evaluated. Among those, 13 were excluded and 44 were recruited into the trial. Their mean age was 62.3± 13.1 years and 32 (72.7%) were male. On univariate analysis, ICH volume on admission CT scan, ICH ipsilateral ONSD measurement on admission TCCD, diabetes and current smoking were predictors of mortality. After multivariate analysis, ipsilateral ONSD (OR:6.24;95CI%1.18-33.1;p=0.031) was an independent predictor of mortality, even after adjustment for ICH volume, age, GCS and intraventricular hemorrhage. The ONSD had an area under the curve (AUC) of 0.71 (p=0.021) for mortality at 3 months.

Conclusion: ONSD is a non-invasively, bedside, low cost technique that could be used to estimate increased ICP in patients with acute supratentorial ICH. Among these patients, increased ONSD is an independent predictor of mortality at 3 months.

Large Vessel Occlusion Score: A Screening Tool to Detect Large Vessel Occlusion in the Acute Stroke Setting

BACKGROUND

The results of recent trials of mechanical thrombectomy for acute ischemic stroke have increased the demand for identification of patients with large vessel occlusion (LVO) at the primary stroke center, where a prompt detection may expedite transfer to a comprehensive stroke center for endovascular treatment. However, in developing countries, a noncontrast computed tomography (NCCT) may be the only neuroimaging modality available at the primary stroke center scenario, what calls for a screening strategy accurate enough to avoid unnecessary transfers of noneligible patients for endovascular therapy. Algorithms based on National Institute of Health Stroke Scale (NIHSS) and NCCT findings can be used to screen for LVO in patients with anterior circulation stroke (ACS).

OBJECTIVE

To test the accuracy of a score based on NIHSS and NCCT to detect LVO in patients with ACS.

METHODS

We evaluated 178 patients from a prospective stroke registry of patients admitted to an academic tertiary emergency unit. NIHSS and vessel attenuation values of the middle cerebral artery on NCCT absolute vessel attenuation (VA) were collected by 2 investigators that were blind to CT angiography (CTA) findings. We used receiver operating characteristics curve analysis and C-statistics to predict LVO on CTA.

RESULTS

NIHSS and vessel attenuation were highly associated with LVO with an area under the curve (AUC) of .86 and .77. The LVO score, built by logistic regression coefficients of the NIHSS and VA, showed the highest accuracy for the presence of LVO on CTA (AUC of .91).

CONCLUSION

The LVO score may be a useful screening approach to identify LVO in patients with ACS.

New biomarker for acute ischaemic stroke: plasma glycogen phosphorylase isoenzyme BB

BACKGROUND

Glycogen phosphorylase is the key enzyme that breaks down glycogen to yield glucose-1-phosphate in order to restore depleted energy stores during cerebral ischaemia. We sought to determine whether plasma levels of glycogen phosphorylase BB (GPBB) isoform increased in patients with acute ischaemic stroke (AIS).

METHODS

We studied plasma GPBB levels within 12 hours and again at 48±24 hours of symptom onset in 172 patients with imaging-confirmed AIS and 133 stroke-free individuals. We determined the ability of plasma GPBB to discriminate between cases and controls and examined the predictive value of plasma GPBB for 90-day functional outcome, 90-day survival and acute lesion volumes on neuroimaging.

RESULTS

The mean (SD) GPBB levels were higher in cases (46.3±38.6 ng/mL at first measurement and 38.6±36.5 ng/mL at second measurement) than in controls (4.1±7.6 ng/mL, p<0.01 for both). The area under the receiver operating characteristic (ROC) curve for case-control discrimination based on first GPBB measurement was 0.96 (95% CI 0.93 to 0.98). The sensitivity and specificity based on optimal operating point on the ROC curve (7.0 ng/mL) were both 93%. GPBB levels increased in 90% of patients with punctate infarcts (<1.5 mL) and in all patients admitted within the first 4.5 hours of onset. There was no correlation between GPBB concentration and either clinical outcome or acute infarct volume.

CONCLUSION

GPBB demonstrates robust response to acute ischaemia and high sensitivity for small infarcts. If confirmed in more diverse populations that also include stroke mimics, GPBB could find utility as a stand-alone marker for acute brain ischaemia.

Abstract TMP88: High Accuracy of Auto-CPAP for Obstructive Sleep Apnea in Acute Stroke Patients

Background: Obstructive sleep apnea (OSA) is very common in acute stroke patients and has been associated with a poor short-term and long-term outcome. Polysomnography (PSG) is the gold standard diagnostic method for OSA, but it is not feasible as a routine for all acute stroke patients. Therefore, it is essential to validade alternative methods to accurately diagnose OSA in acute stroke patients. The newest generation of automatic continuous positive airway pressure (auto-CPAP) devices innovates by the possibility of detecting the different types of respiratory events. However, the accuracy of auto-CPAP devices for OSA diagnosis has never been tested in comparison to PSG in the acute stroke setting. The main objective of this study was to evaluate the accuracy of an auto-CPAP device to diagnose OSA and to validate its algorithm of respiratory events detection to diagnose OSA in patients during the acute phase of stroke.

Methods: A sleep study was performed with PSG and auto-CPAP device, simultaneously, within the first 48 hours after the acute stroke onset. The Receiver Operating Characteristic Curve (ROC), C-statistics, Spearman correlation coefficient, and intraclass correlation coefficient were analyzed.

Results: We prospectively evaluated 31 adult patients with acute stroke. The mean age was 59.7 ± 12 years and 60% were males. All patients used auto-CPAP for longer than 4 hours. The PSG revealed an apnea-hypopnea index (AHI) mean of 34 ± 41 events/h, and the auto-CPAP showed an AHI of 18 ± 16 events/h. The area under the ROC curve for OSA diagnosis by the auto-CPAP was above 0.90, with sensitivity and specificity above 80% for each AHI value. The Spearman correlation coefficients (rs) of the AHI, of the hypopnea index, of the obstructive apnea index and of the central apnea index were 0.92; 0.89; 0.63 and 0.62, respectively. The intraclass correlation coefficients between device-detected and PSG manually scored events were 0.60 for AHI, 0.64 for hypopnea index, and 0.45 for apnea index.

Conclusion: The auto-CPAP showed an excellent accuracy for the diagnosis of OSA and it was well tolerated by acute stroke patients. Our results suggest that auto-CPAP should be considered as the preferred diagnostic tool for OSA diagnosis during the acute phase of stroke.

Abstract TP422: Cerebral Perfusion, Functional Connectivity and Cognitive Profile of Patients With Assymptomatic Carotid Stenosis

Introduction: Patients with carotid stenosis, without history of stroke or transient ischemic attack are considered to be asymptomatic. However, many of those patients might have some degree of cognitive decline, changes in perfusion and functional connectivity that may precede clinical events suggesting a high risk for stroke. In this study, we aimed to evaluate the frequency and severity of cerebral blood flow (CBF), functional connectivity (FC) and cognitive performance abnormalities in patients with severe “asymptomatic” carotid artery stenosis (aCAS).

Methods: Fifteen patients with aCAS >70% and 15 controls were evaluated with 3T MRI, including BOLD-FMRI, Pseudo-continuous Arterial Spin Labeling and Resting-State Brain Networks. The cognitive assessment included tests for executive function, psychomotor speed, attention and memory. We used Mann-Whitney U Test to compare cognition and CBF between groups; Wilcoxon test for intragroup CBF differences; Spearman Correlation Coefficient for associations between CBF, FC and cognition.

Results: CBF maps in patients with aCAS revealed reduction in blood flow in the gray matter of temporal lobes and internal structures when compared to controls (p<0.05). The cognitive performance of patients with aCAS was lower than the control group for all measures, with significant differences in attention, mnemonic process and executive functions (p<0.05). Patients presented decreased connectivity for the fronto-temporal, salience and dorsal attentional networks (p-FDR<0.01). Additionally, we observed significant correlations (p<0.01) between salience network and the cognitive measures performed in this study.

Conclusions: Subjects with aCAS showed less expressive networks and significantly lower cognitive performance, indicating deficits in fundamental networks for the identification of relevant stimuli, neural resource coordination, and information processing. We identified preclinical abnormalities in CBF, FC and cognitive performance of patients with aCAS, suggesting that neuroimaging markers in MRI, combined with cognitive assessment, have a great potential to identify the profile of patients with high risk of stroke and cognitive decline.

Abstract WP22: Collateral Score and Outcome After Endovascular Treatment for Basilar Occlusion

Introduction: Basilar artery occlusion (BAO) is a rare stroke subtype with high morbidity and mortality rates. Best reperfusion strategy is still somewhat controversial and is currently under investigation in multicenter randomized trials. We aim to describe outcomes of BAO patients submitted to mechanical thrombectomy in a comprehensive stroke center in Brazil and analyze which previous published computed tomography angiography (CTA) collateral score better predicts functional outcomes.

Methods: Retrospective analysis of consecutive BAO patients from a prospective stroke registry. BAO was diagnosed through CTAs, which were also used to evaluate the Posterior Circulation Collateral Score (PC-CS), the Basilar Artery on Computed Tomography Angiography (BATMAN) scores and also for the presence of both posterior communicating arteries. A favorable outcome was defined as a mRS ≤3 at 90 days. After univariate analyses, multivariate logistic regression was used to identify if any collateral score independently predicts a favorable outcome. We also used ROC curves and C-statistics for score comparisons.

Results: Between January/2011 and April/2017, 27 (85% male) BAO patients with median NIHSS of 26 (IQR:15-32) were identified. Twenty-five (93%) patients were treated with a stent-retriever or an aspiration device, and only 2 (7%) patients were treated with basilar artery angioplasty and stenting. Recanalization rate was 85% and only 1 (3.7%) patient had a symptomatic hemorrhagic transformation. Favorable outcomes were reached in 10 (37%) patients at 90-days and mortality rate was 37%. In univariate analysis, female sex, NIHSS, onset-to-groin time and PC-CS predict favorable outcomes. In multivariate analysis, only PC-CS (OR=1.69;95%CI:1.10-2.60;p=0.016) and the baseline NIHSS (OR=0.84;95%CI:0.77-0.93;p=0.001) remained as independent predictors of favorable outcomes. The PC-CS AUC for favorable outcome was 0.80 (95%CI:0.62-0.98;p=0.012).

Conclusions: Mechanical thrombectomy seems to be a promising strategy for patients with acute BAO. Collateral flow assessment using the PC-CS is an independent predictor of favorable outcomes among acute BAO patients treated with mechanical thrombectomy.

Low-Dose vs Standard-Dose Alteplase for Patients With Acute Ischemic Stroke: Secondary Analysis of the ENCHANTED Randomized Clinical Trial

Importance

A lower dose of intravenous alteplase appears to be a safer treatment option than the standard dose, reducing the risk of symptomatic intracerebral hemorrhage. There is uncertainty, however, over how this effect translates into an overall clinical benefit for patients with acute ischemic stroke (AIS).

Objective

To assess whether older, Asian, or severely affected patients with AIS who are considered at high risk of thrombolysis may benefit more from low-dose rather than standard-dose alteplase treatment.

Design, Setting, and Participants

This study is a prespecified secondary analysis of the Enhanced Control of Hypertension and Thrombolysis Stroke Study (ENCHANTED), an international, randomized, open-label, blinded, end-point clinical trial of low-dose vs standard-dose intravenous alteplase for patients with AIS. From March 1, 2012, to August 31, 2015, a total of 3310 patients who had a clinical diagnosis of AIS as confirmed by brain imaging and who fulfilled the local criteria for thrombolysis treatment were included in the alteplase-dose arms. Patients were randomly assigned to receive low-dose (0.6 mg/kg; 15% as bolus and 85% as infusion over 1 hour) or standard-dose (0.9 mg/kg; 10% as bolus and 90% as infusion over 1 hour) alteplase. Of the 3310 randomized patients, 13 patients were excluded for missing consent, mistaken randomization, and duplicate randomization numbers. This secondary analysis was conducted between May 1, 2016, and April 28, 2017.

Main Outcomes and Measures

The primary end point was a poor outcome defined by the combination of death and any disability as scored by the modified Rankin Scale (scores range from 2 to 6, with the highest score indicating death) at 90 days.

Results

Of the 3297 patients included in the analysis, 1248 (37.9%) were women, and the mean (SD) age was 67 (13) years. No significant differences in the treatment effects were observed between low- and standard-dose alteplase for poor outcomes (death or disability) by age, ethnicity, or severity (all P > .37 for interaction). Similarly, the treatment effects of low- vs standard-dose alteplase on function outcome (ordinal shift of the modified Rankin Scale) in Asians (odds ratio, 1.05; 95% CI, 0.90-1.22) was consistent with non-Asians (odds ratio, 0.93; 95% CI, 0.76-1.14) (P = .32 for interaction). There were generally consistent reductions in rates of symptomatic intracerebral hemorrhage with low-dose alteplase, although this reduction was not statistically significant by age, ethnicity, or severity.

Conclusions and Relevance

This analysis found that the effects of low-dose alteplase were not clearly superior to the effects of standard-dose alteplase on death or disability in key demographic subgroups of patients with AIS. Further investigation is required to identify patients with AIS who may benefit from low-dose alteplase.

Trial Registration

clinicaltrials.gov Identifier: NCT01422616.

Hyper-attenuating brain lesions on CT after ischemic stroke and thrombectomy are associated with final brain infarction

Purpose Hyper-attenuating lesions, or contrast staining, on a non-contrast brain computed tomography (NCCT) scan have been investigated as a predictor for hemorrhagic transformation after endovascular treatment of acute ischemic stroke (AIS). However, the association of hyper-attenuating lesions and final ischemic areas are poorly investigated in this setting. The aim of the present study was to assess correlations between hyper-attenuating lesions and final brain infarcted areas after thrombectomy for AIS. Methods Data from patients with AIS of the anterior circulation who underwent endovascular treatment were retrospectively assessed. Images of the brain NCCT scans were analyzed in the first hours and late after treatment. The hyper-attenuating areas were compared to the final ischemic areas using the Alberta Stroke Program Early CT Score (ASPECTS). Results Seventy-one of the 123 patients (65.13%) treated were included. The association between the hyper-attenuating region in the post-thrombectomy CT scan and final brain ischemic area were sensitivity (58.3% to 96.9%), specificity (42.9% to 95.6%), positive predictive values (71.4% to 97.7%), negative predictive values (53.8% to 79.5%), and accuracy values (68% to 91%). The highest sensitivity values were found for the lentiform (96.9%) and caudate nuclei (80.4%) and for the internal capsule (87.5%), and the lowest values were found for the M1 (58.3%) and M6 (66.7%) cortices. Conclusions Hyper-attenuating lesions on head NCCT scans performed after endovascular treatment of AIS may predict final brain infarcted areas. The prediction appears to be higher in the deep brain regions compared with the cortical regions.

Assessment of the Predictive Validity of Etiologic Stroke Classification

Importance

The ability of present-day etiologic stroke classification systems to generate subtypes with discrete stroke characteristics is not known.

Objective

To test the hypothesis that etiologic stroke subtyping identifies different disease processes that can be recognized through their different clinical courses.

Design, Setting, and Participants

We performed a head-to-head evaluation of the ability of the Causative Classification of Stroke (CCS), Trial of Org 10172 in Acute Stroke Treatment (TOAST), and ASCO (A for atherosclerosis, S for small-vessel disease, C for cardiac source, and O for other cause) classification systems to generate etiologic subtypes with different clinical, imaging, and prognostic characteristics in 1816 patients with ischemic stroke. This study included 2 cohorts recruited at separate periods; the first cohort was recruited between April 2003 and June 2006 and the second between June 2009 and December 2011. Data analysis was performed between June 2014 and May 2016.

Main Outcomes and Measures

Separate teams of stroke-trained neurologists performed CCS, TOAST, and ASCO classifications based on information available at the time of hospital discharge. We assessed the association between etiologic subtypes and stroke characteristics by computing receiver operating characteristic curves for binary variables (90-day stroke recurrence and 90-day mortality) and by calculating the ratio of between-category to within-category variability from the analysis of variance for continuous variables (admission National Institutes of Health Stroke Scale score and acute infarct volume).

Results

Among the 1816 patients included, the median age was 70 years (interquartile range, 58-80 years) (830 women [46%]). The classification systems differed in their ability to assign stroke etiologies into known subtypes; the size of the undetermined category was 33% by CCS, 53% by TOAST, and 42% by ASCO (P < .001 for all binary comparisons). All systems provided significant discrimination for the validation variables tested. For the primary validation variable (90-day recurrence), the area under the receiver operating characteristic curve was 0.71 (95% CI, 0.66-0.75) for CCS, 0.61 (95% CI, 0.56-0.67) for TOAST, and 0.66 (95% CI, 0.60-0.71) for ASCO (P = .01 for CCS vs ASCO; P < .001 for CCS vs TOAST; P = .13 for ASCO vs TOAST). The classification systems exhibited similar discrimination for 90-day mortality. For admission National Institutes of Health Stroke Scale score and acute infarct volume, CCS generated more distinct subtypes with higher between-category to within-category variability than TOAST and ASCO.

Conclusions and Relevance

Our findings suggest that the major etiologic stroke subtypes are distinct categories with different stroke characteristics irrespective of the classification system used to identify them. We further show that CCS generates discrete etiologic categories with more diverse clinical, imaging, and prognostic characteristics than either TOAST or ASCO.

Cerebral blood flow and vasoreactivity in aging: an arterial spin labeling study

Regional cerebral blood flow (CBF) and cerebrovascular reactivity (CVR) in young and elderly participants were assessed using pulsed arterial spin labeling (ASL) and blood oxygenation level-dependent (BOLD) magnetic resonance imaging (MRI) techniques in combination with inhalation of CO₂. Pulsed ASL and BOLD-MRI were acquired in seventeen asymptomatic volunteers (10 young adults, age: 30±7 years; 7 elderly adults, age: 64±8 years) with no history of diabetes, hypertension, and neurological diseases. Data from one elderly participant was excluded due to the incorrigible head motion. Average baseline CBF in gray matter was significantly reduced in elderly (46±9 mL·100 g^-1·min^-1) compared to young adults (57±8 mL·100 g^-1·min^-1; P=0.02). Decreased pulsed ASL-CVR and BOLD-CVR in gray matter were also observed in elderly (2.12±1.30 and 0.13±0.06 %/mmHg, respectively) compared to young adults (3.28±1.43 and 0.28±0.11 %/mmHg, respectively; P<0.05), suggesting some degree of vascular impairment with aging. Moreover, age-related decrease in baseline CBF was observed in different brain regions (inferior, middle and superior frontal gyri; precentral and postcentral gyri; superior temporal gyrus; cingulate gyri; insula, putamen, caudate, and supramarginal gyrus). In conclusion, CBF and CVR were successfully investigated using a protocol that causes minimal or no discomfort for the participants. Age-related decreases in baseline CBF and CVR were observed in the cerebral cortex, which may be related to the vulnerability for neurological disorders in aging.

Abstract TP371: Monitoring a Large-scale International Cluster Stroke Trial: Lessons From Head Position in Stroke Trial

Background and Purpose: There is limited evidence on head positioning in acute ischemic stroke (AIS) or intracerebral hemorrhage (ICH). Potential benefits for lying flat (0°) include improved collateral blood flow in AIS and for head up (30°) reduced cerebral oedema in ICH. The Head Positioning in Stroke Trial (HeadPoST) aims to provide reliable evidence on the optimum head position in acute stroke.

Methods: HeadPoST is a prospective, cluster randomised, crossover, blinded outcome assessed, clinical trial with consecutive patient recruitment who were positioned within 24 hours of admission. Hospitals were randomised to service organisation to compare lying flat vs. sitting up (≥30°) head positioning of stroke patients. An innovative centralized remote monitoring system was used to assess data quality across participating countries.

Results: Over a 30 month study period, 10,000+ patients were recruited across 114 hospitals in 9 countries. A web-based monitoring system provided alerts for cross-over time points and achievement of cluster balance. Centralised reports included serious adverse events, protocol deviations, forms completion, data queries, entry delays and data validation, which were distributed to regional co-ordinating centres for action. Details of these procedures are outlined.

Conclusions: Reliable, complete, and high quality data were required for this pragmatic international nursing care clinical trial, which used a novel cluster cross-over design.

Low-Dose versus Standard-Dose Intravenous Alteplase in Acute Ischemic Stroke

BACKGROUND

Thrombolytic therapy for acute ischemic stroke with a lower-than-standard dose of intravenous alteplase may improve recovery along with a reduced risk of intracerebral hemorrhage.

METHODS

Using a 2-by-2 quasi-factorial open-label design, we randomly assigned 3310 patients who were eligible for thrombolytic therapy (median age, 67 years; 63% Asian) to low-dose intravenous alteplase (0.6 mg per kilogram of body weight) or the standard dose (0.9 mg per kilogram); patients underwent randomization within 4.5 hours after the onset of stroke. The primary objective was to determine whether the low dose would be noninferior to the standard dose with respect to the primary outcome of death or disability at 90 days, which was defined by scores of 2 to 6 on the modified Rankin scale (range, 0 [no symptoms] to 6 [death]). Secondary objectives were to determine whether the low dose would be superior to the standard dose with respect to centrally adjudicated symptomatic intracerebral hemorrhage and whether the low dose would be noninferior in an ordinal analysis of modified Rankin scale scores (testing for an improvement in the distribution of scores). The trial included 935 patients who were also randomly assigned to intensive or guideline-recommended blood-pressure control.

RESULTS

The primary outcome occurred in 855 of 1607 participants (53.2%) in the low-dose group and in 817 of 1599 participants (51.1%) in the standard-dose group (odds ratio, 1.09; 95% confidence interval [CI], 0.95 to 1.25; the upper boundary exceeded the noninferiority margin of 1.14; P=0.51 for noninferiority). Low-dose alteplase was noninferior in the ordinal analysis of modified Rankin scale scores (unadjusted common odds ratio, 1.00; 95% CI, 0.89 to 1.13; P=0.04 for noninferiority). Major symptomatic intracerebral hemorrhage occurred in 1.0% of the participants in the low-dose group and in 2.1% of the participants in the standard-dose group (P=0.01); fatal events occurred within 7 days in 0.5% and 1.5%, respectively (P=0.01). Mortality at 90 days did not differ significantly between the two groups (8.5% and 10.3%, respectively; P=0.07).

CONCLUSIONS

This trial involving predominantly Asian patients with acute ischemic stroke did not show the noninferiority of low-dose alteplase to standard-dose alteplase with respect to death and disability at 90 days. There were significantly fewer symptomatic intracerebral hemorrhages with low-dose alteplase. (Funded by the National Health and Medical Research Council of Australia and others; ENCHANTED ClinicalTrials.gov number, NCT01422616.).

Trends of Stroke Incidence from 1995 to 2013 in Joinville, Brazil

BACKGROUND

Temporal trends on the incidence of stroke and its subtypes could help assess on-going public health policies and point to further targets for action among middle- and low-income countries, where the stroke burden is very high. This study aimed at evaluating longitudinal trends of stroke incidence in Joinville, Brazil.

METHODS

We ascertained the incidence of all first-ever strokes occurred in 1995, 2005-2006 and 2012-2013, which were extracted from Joinville Stroke Registry, a prospective epidemiological data bank, launched in 1995.

RESULTS

From 1995 to 2013, the age-adjusted incidence of all strokes decreased 37% (95% CI 32-42). From 2005 to 2013, the haemorrhagic stroke (HS) incidence decreased 60% (95% CI 13-86), ischemic stroke (IS) incidence decreased 15% (95% CI 1-28), and subarachnoid haemorrhage incidence remained stable. The proportion of IS and HS patients with regularly treated hypertension increased by 60% (p = 0.01) and 33% (p = 0.01), respectively. The proportion of IS and HS patients that quit smoking increased 8% (p = 0.03) and 17% (p = 0.03), respectively.

CONCLUSIONS

Stroke incidence has been decreasing in Joinville over the last 18 years, more so for HS than IS. Better control of hypertension and tobacco use might explain these findings.

Polarity-Dependent Misperception of Subjective Visual Vertical during and after Transcranial Direct Current Stimulation (tDCS)

Pathologic tilt of subjective visual vertical (SVV) frequently has adverse functional consequences for patients with stroke and vestibular disorders. Repetitive transcranial magnetic stimulation (rTMS) of the supramarginal gyrus can produce a transitory tilt on SVV in healthy subjects. However, the effect of transcranial direct current stimulation (tDCS) on SVV has never been systematically studied. We investigated whether bilateral tDCS over the temporal-parietal region could result in both online and offline SVV misperception in healthy subjects. In a randomized, sham-controlled, single-blind crossover pilot study, thirteen healthy subjects performed tests of SVV before, during and after the tDCS applied over the temporal-parietal region in three conditions used on different days: right anode/left cathode; right cathode/left anode; and sham. Subjects were blind to the tDCS conditions. Montage-specific current flow patterns were investigated using computational models. SVV was significantly displaced towards the anode during both active stimulation conditions when compared to sham condition. Immediately after both active conditions, there were rebound effects. Longer lasting after-effects towards the anode occurred only in the right cathode/left anode condition. Current flow models predicted the stimulation of temporal-parietal regions under the electrodes and deep clusters in the posterior limb of the internal capsule. The present findings indicate that tDCS over the temporal-parietal region can significantly alter human SVV perception. This tDCS approach may be a potential clinical tool for the treatment of SVV misperception in neurological patients.

Abstract TP46: A Score to Detect Proximal Artery Occlusion in Patients With Acute Ischemic Stroke of the Anterior Circulation Based on NIHSS and Non-contrast Brain CT: the PAO Score

Introduction: After the results of the new endovascular trials that demonstrated a robust effect of endovascular treatment for acute ischemic stroke (AIS), early detection of proximal artery occlusion (PAO) has become a fundamental task during the initial assessment of acute stroke patients at the emergency department. Nevertheless, an accurate identification of PAO may be particularly challenging in smaller hospitals and in developing countries, areas with restricted assess to vascular neuroimaging modalities such as CTA and MRA.

Hypothesis: Algorithms based on NIHSS and non-contrasted CT (NCCT) findings can be accurately used to detect PAO in patients with AIS of the anterior circulation.

Method: We retrospectively evaluated 194 consecutive patients with AIS of the anterior circulation from a prospective stroke registry of patients admitted to an academic tertiary emergency unit in Brazil during 2014 that had a NCCT and a CTA at admission. NIHSS scores and attenuation of major intracranial arteries of the anterior circulation on NCCT were collected by two experienced investigators that were blind to the CT angiography findings. We used a ratio between two ROIs (rVA) that were drawn on NCCT blinded to CT angiography: (i) on the region of highest vessel attenuation ipsilateral to the involved hemisphere and (ii) mirror ROI on the corresponding vessel segment of the contralateral hemisphere. We used ROC curve analysis and C-statistics to predict CT angiography PAO.

Results: NIHSS and vessel attenuation values were highly associated with the PAO with an area under the curve (AUC) of 0.88 (p < 0,001) and 0.83 (p < 0,001), respectively. An NIHSS of 10 at admission had a sensitivity, and negative predictive value of 97% and 97%, respectively. The rVA ≥ 1.50 had a specificity and positive predictive value 96% and 85%, respectively. The POA score was then built by logistic regression from NIHSS and rVA and showed even higher accuracy for the presence of POA on CTA, with an AUC of 0.93 (p < 0,001).

Conclusion: The PAO score based on admission NIHSS and proximal vessel attenuation on NCCT can be accurately used to detect PAO in patients with AIS of the anterior circulation. Further studies are necessary to validate this score in a multicenter setting.

Rationale, Design, and Progress of the ENhanced Control of Hypertension ANd Thrombolysis Stroke Study (ENCHANTED) Trial: An International Multicenter 2 × 2 Quasi-Factorial Randomized Controlled Trial of Low- vs. Standard-Dose rt-PA and Early Intensive vs. Guideline-Recommended Blood Pressure Lowering in Patients with Acute Ischaemic Stroke Eligible for Thrombolysis Treatment

Rationale

Controversy exists over the optimal dose of intravenous (iv) recombinant tissue plasminogen activator (rt-PA) and degree of blood pressure (BP) control in acute ischaemic stroke (AIS). Asian studies suggest low-dose (0·6 mg/kg) is more efficacious than standard-dose (0·9 mg/kg) iv rt-PA, and guidelines recommend reducing systolic BP to <185 mmHg before and <180 mmHg after use of iv rt-PA, despite observational studies indicating better outcomes at much lower (<140 mmHg) systolic BP levels in this patient group.

Aims

The study aims to assess in thrombolysis-eligible AIS patients whether: (i) low-dose (0·6 mg/kg body weight; maximum 60 mg) iv rt-PA has non-inferior efficacy and lower risk of symptomatic intracerebral haemorrhage (sICH) compared to standard-dose (0·9 mg/kg body weight; maximum 90 mg) iv rt-PA; and (ii) early intensive BP lowering (systolic target 130–140 mmHg) has superior efficacy and lower risk of any ICH compared to guideline-recommended BP control (systolic target < 180 mmHg).

Design

The ENhanced Control of Hypertension And Thrombolysis strokE stuDy (ENCHANTED) trial is an independent, 2 × 2 quasi-factorial, active-comparison, prospective, randomized, open blinded endpoint (PROBE), clinical trial that is evaluating Arm [A] ‘rt-PA dose’ and/or Arm [B] ‘BP control’, using central Internet randomization and data collection in patients fulfilling local criteria for thrombolysis and clinician uncertainty over the study treatments. The treatment arms will be analyzed separately.

Study outcomes

The primary study outcome in both trial Arms is death or disability according to the modified Rankin scale (mRS, scores 2–6) assessed at 90 days. Secondary outcomes include sICH, any ICH, a shift (‘improvement’) in function across mRS scores, separately on death and disability, early neurological deterioration, recurrent major vascular events, health-related quality of life, length of hospital stay, need for permanent residential care, and health care costs.

Results

Following launch of the trial in February 2012, the study has recruited more than 2500 patients across a global network of approximately 100 sites in 15 countries. The required sample sizes are 3300 for Arm [A] and 2300 for Arm [B], which will provide >90% power to detect non-inferiority of low-dose iv rt-PA and superiority of intensive BP lowering on the primary clinical outcome, respectively.

Conclusions

Low-dose iv rt-PA and early intensive BP lowering could provide more affordable and safer use of thrombolysis treatment for patients with AIS worldwide.

Validation of a structured interview for telephone assessment of the modified Rankin Scale in Brazilian stroke patients

BACKGROUND

The modified Rankin Scale (mRS) is a commonly used scale to assess the functional outcome after stroke. Several studies on mRS showed good reliability, feasibility, and interrater agreement of this scale using a face-to-face assessment. However, telephone assessment is a more time-efficient way to obtain an mRS grade than a face-to-face interview. The aim of this study was to validate the telephone assessment of mRS among the Portuguese using a structured interview in a sample of Brazilian stroke patients.

METHODS

We evaluated 50 stroke outpatients twice. The first interview was face-to-face and the second was made by telephone and the time between the two assessments ranged between 7 and 14 days. Four certified raters evaluated the patients using a structured interview based on a questionnaire previously published in the literature. Raters were blinded for the Rankin score given by the other rater. For both assessments, the rater could also interview a caregiver if necessary.

RESULTS

The patients' mean age was 62.8 ± 14.7, mean number of years of study 5.2 ± 3.4, 52% were males, 55.2% of patients needed a caregiver's help to answer the questions. The majority of caregivers were female (85%), mean age 49.1 ± 15, and mean number of years of study 8.3 ± 3.4. Perfect agreement between the telephone and face-to-face assessments was obtained for 27 (54%) patients, corresponding to an unweighted Kappa of 0.44 (95% CI 0.27-0.61) and a weighted Kappa of 0.89. The median of telephone assessment mRS was 3.5 (interquartile range = 2-4) and of face-to-face assessment was 4 (interquartile range = 2-5). There was no difference between the two assessments (Wilcoxon test, p = 0.35).

CONCLUSIONS

Despite the low education level of our sample, the telephone assessment of functional impairment of stroke patients using a translated and culturally adapted Brazilian Portuguese version of the mRS showed good validity and reliability. Therefore, the telephone assessment of mRS can be used in clinical practice and scientific studies in Brazil.

Abstract T MP13: Chagas Disease Related Stroke: Safety of Intravenous Thrombolysis and Endovascular Treatment

Background: AND AIM: Chagas disease (CD) is a common cause of stroke in undeveloped countries and has become more frequent in the US, where it is largely underestimated. CD related strokes are believed to be mainly cardioembolic but some studies have suggested concomitant cerebral vasculitis. Data on the safety of recanalization therapies in patients with acute stroke related to CD is still restricted to single case reports. We aimed to assess the rate of symptomatic intracranial hemorrhage (SIH) in a group of patients with CD-related stroke treated with intravenous tissue plasminogen activator (IV TPA) and/or endovascular therapy.

METHODS: We performed a retrospective analysis of a prospective, single-center, hospital-based registry of acute stroke patients treated with IV TPA and/or endovascular therapy and routinely tested for CD. Demographics, medical history and clinical data were obtained from the registry. CT scans at admission and after 24-48 hours were blindly reviewed by two experienced stroke neurologists, who rated the presence of hemorrhage transformation according to the European Cooperative Acute Stroke Study criteria.

RESULTS: From 2001 to 2012, 197 patients met the inclusion criteria for this study. CD was diagnosed in 30 patients (15.2%). Patients with CD had higher admission scores on the National Institute of Health Stroke Scale [median: 19; interquartile range (IR): 16-22; no CD: 14; IR: 9-19; P<0.01]. Among patients treated with IV TPA, the rate of SIH was similar among patients with CD (1/24; 4.2%) and patients without CD (8/150; 5.3%; OR: 0.77, 95% CI: 0.09-6.46; P=0.99). Among those treated with rescue endovascular treatment, SIH occurred in 2/6 (33.3%) patients with CD and in 3/17 (17.6%) patients without CD (OR: 2.33, 95%CI: 0.28-19.17, P=0.58). Overall, there was no difference in mortality between groups [CD: 6 (20%); no CD: 24 (14.4%); OR: 1.49; 95% CI: 0.55-4.0; P=0.42].

CONCLUSIONS: In the largest series of patients with acute stroke related to CD treated with recanalization therapies ever reported, we found that IV TPA appears to be safe in these patients. Further studies are necessary to confirm the safety and efficacy of endovascular recanalization strategies in patients with CD.