Posttreatment National Institutes of Health Stroke Scale Is Superior to the Initial Score or Thrombolysis in Cerebral Ischemia for 3-Month Outcome.

BACKGROUND AND PURPOSE: The majority of ischemic stroke patients receiving endovascular recanalization therapy (EVT) experience variable changes of neurological severities during the hyperacute period. We hypothesized that the National Institutes of Health Stroke Scale (NIHSS) score after EVT is a better prognostic factor compared with the initial NIHSS score or revascularization status. METHODS: We identified 566 stroke patients who received EVT at Seoul National University Bundang Hospital between April 2008 and December 2015. We prospectively collected post-EVT NIHSS score, which was measured in the angiography suite by on-duty physicians after completion of EVT. Model 1 included baseline predictors including an initial NIHSS score. In model 2, 3, and 4, revascularization status, post-EVT NIHSS score, or both were additionally included. The discrimination powers for modified Rankin Scale score of 0 to 2 at 3 months were assessed using C statistic, integrated discrimination index, and category-free net reclassification index. RESULTS: The median of initial and post-EVT NIHSS score were 14 (9-19) and 11 (5-17) points, respectively (an improvement, 58.8%; no change, 20.7%; deterioration, 20.5%). A modified Rankin Scale score 0 to 2 at 3 months was achieved in 47%. Based on the results of differences among the C statistics, both model 3 and model 4 (C statistics: 0.896 and 0.906) showed significantly increased discrimination power for modified Rankin Scale score 0 to 2 at 3 months than the model 1 or 2 (C statistics: 0.802 and 0.834, P values<0.001 for all comparisons). Model 4 showed significant improvement of both integrated discrimination index and net reclassification index as compared with all other models, but the magnitude of improvement from model 3 to model 4 (integrated discrimination index, 0.021; net reclassification index, 0.322) was modest. CONCLUSIONS: Incorporation of post-EVT NIHSS score conferred better discrimination power to the statistical models for functional recovery. Post-EVT NIHSS score may be an appropriate baseline factor when evaluating an intervention after hyperacute period.

Tenacity of Collateral Perfusion in Proximal Cerebral Arterial Occlusions 6-12 h after Onset.

BACKGROUND: Clinical trials have shown that benefits of endovascular recanalization (EVT) for acute ischemic stroke patients with sizable penumbral tissues seems plausible even beyond 6 h after their last seen normal (LSN). Persistency of ischemic penumbra remains unclear in delayed periods. METHODS: From a prospective stroke registry database, we identified 111 acute ischemic stroke patients who had internal carotid artery or middle cerebral artery occlusion with baseline National Institutes of Health Stroke Scale scores ≥6 points and arrived 6-12 h after LSN. Baseline information and functional outcomes were prospectively collected as a clinical registry. Attending physicians made treatment decisions for EVT based on the current guidelines and institutional protocols. MR image parameters, including the volume of diffusion-restricted lesions and mapping of the -hypoperfused area, were quantified using automated commercial software. Binary logistic regression analysis models, with modified Rankin Scale (mRS) scores of 0-1 at 3 months after stroke included as a dependent variable, were constructed. RESULTS: Between 6 and 12 h after onset, 58% had a mismatch ratio of ≥1.8 at baseline and 42% had favorable imaging profiles as determined by DEFUSE 2 study. After 9 h, there was a mismatch ratio of ≥1.8 in 47 and 38% favorable profiles. EVT was performed in 54% of cases. A 3-month mRS score of 0-1 was found in 19% (25% in EVT and 12% in medical treatment groups) of cases. EVT was associated with an increased OR of having a mRS score of 0-1 at 3 months after stroke (adjusted OR 7.59 [95% CI 1.28-61.60]). CONCLUSIONS: Penumbral tissues were persistent in a substantial proportion of anterior circulation occlusion cases 6-12 h after LSN. EVT at 6-12 h in a predominantly Asian cohort resulted in better outcomes.

The Role of the Signal Intensity Ratio on Fluid-Attenuated Inversion Recovery in Stroke Patients Achieving Successful Recanalization with Endovascular Treatment.

BACKGROUND: This study aimed to investigate whether fluid-attenuated inversion recovery (FLAIR) imaging hyperintensity can be used as a surrogate marker for the severity of ischemic insult and predict lesion growth. METHODS: Based on a prospective stroke registry database, we identified patients with ischemic stroke who were treated with endovascular treatment (EVT) within 8 hours of onset and achieved successful recanalization (modified thrombolysis in cerebral infarction ≥2B). FLAIR hyperintensity was measured using the signal intensity ratio (SIR), defined as the mean SIR of diffusion-restricted lesions to the corresponding areas in the contralateral hemisphere. Lesion growth was defined as the ratio of final infarct volume on follow-up FLAIR to initial infarct volume on diffusion-weighted imaging. RESULTS: For 69 patients meeting the eligibility criteria, the median FLAIR SIR was 1.17 (interquartile range, 1.08-1.23) and the median lesion growth ratio was 1.70 (interquartile range, 1.35-2.79) (Pearson's r = -.146, P = .231). In multiple linear regression models, the FLAIR SIR was not significantly correlated with the lesion growth ratio. Interestingly, the time interval from initial magnetic resonance imaging (MRI) to successful recanalization was independently correlated with the lesion growth ratio (ß = .072, P < .001). With respect to clinical outcomes, the FLAIR SIR was not associated with either discharge modified Rankin scale score ≤2 (ß = -3.41, P = .30) or symptomatic hemorrhagic transformation (ß = 2.75; P = .63). CONCLUSIONS: Contrary to our hypothesis, FLAIR hyperintensity on initial MRI before EVT was not associated with lesion growth in patients who were recanalized successfully with EVT. Instead, our results suggest that time interval from MRI acquisition to recanalization is an independent predictor of lesion growth.

Neuroimaging markers for early neurologic deterioration in single small subcortical infarction.

BACKGROUND AND PURPOSE: Early neurological deterioration (END) occurs in ≥20% of single small subcortical infarctions (SSSIs; axial diameter ≤20 mm in the perforator territories) and deters functional recovery. Both microvasculopathies and atherosclerosis have been proposed to independently contribute to the occurrence of END in SSSI cases. We hypothesized that the occurrence of END in SSSIs differs according to the pathological process. METHODS: We collected data from 587 patients with SSSI within 48 hours of onset from a prospective stroke registry containing 4961 case records. Independent reviewers, blinded to END information, rated neuroimaging characteristics, including relevant artery stenosis (0% to 50% stenosis of the adjacent arteries on magnetic resonance angiography), branch atheromatous lesions (≥4 consecutive axial cuts or extensions from the basal surface of the pons), white matter hyperintensities, old lacunar infarctions, and cerebral microbleeds. RESULTS: END occurred in 79 (13.5%) cases, including 6 recurrences, 68 progressions, 1 symptomatic hemorrhagic transformation, 1 others, and 3 unknowns. END increased the National Institutes of Health Stroke Scale score by 2.3±1.4 points. Patients with END showed higher frequencies of modified Rankin Scale scores of 3 to 6 after 3 months compared with patients without END (49% versus 23%). Patients with relevant artery stenosis (adjusted odds ratio, 1.91; 95% confidence interval, 1.13-3.21) and branch atheromatous lesions (adjusted odds ratio, 2.98; 95% confidence interval, 1.80-4.93) had significantly higher odds of exhibiting END. However, such an association was not detected with small vessel disease markers. CONCLUSIONS: Our analysis indicated a potential contribution of the localized atherosclerotic process to END in SSSIs. Precautionary measures might be used for SSSIs suggestive of atherosclerotic pathologies.

A Simple Geometric Assessment of Perfusion Lesion Volume at Hyperacute Stage of Ischemic Stroke in Patients with Symptomatic Steno-Occlusion of Major Cerebral Arteries and Risk of Subsequent Cerebral Ischemic Events.

Our objective is to elucidate the association of baseline perfusion lesion volume on perfusion-weighted magnetic resonance imaging (PWI) obtained at hyperacute stage of ischemic stroke with subsequent cerebral ischemic events (SIEs) in patients with symptomatic steno-occlusion of major cerebral arteries. Using a prospective stroke registry database, patients arriving within 24 hours of onset with symptomatic steno-occlusion of major supratentorial cerebral arteries were identified. On baseline PWI, time-to-peak lesion volume (TTP-LV) was determined by a simple geometric method and dichotomized into the highest tertile (large) and the other tertiles (small to medium) according to the vascular territory of occluded arteries. Primary outcome was a time to SIE up to 1 year after stroke onset. A total of 385 patients (a median time delay from onset to arrival, 2.2 hours) were enrolled. During the first year of stroke, the SIE rate of the large TTP-LV group was twice that of the small-to-medium TTP-LV group (35.7% versus 17.4%; P < .001). Large TTP-LV independently raised the hazard of SIE (hazard ratio, 2.24; 95% confidence interval, 1.45-3.44). This study demonstrates that TTP-LV on PWI measured through a simple geometric method at an emergency setting can be used to predict progression or recurrence of ischemic stroke in patients with symptomatic steno-occlusion of major cerebral arteries.

Genetic analysis of human parainfluenza viruses circulating in Korea, 2006.

Human parainfluenza viruses (HPIV) are important causes of respiratory tract infections in young children. To characterize the molecular epidemiology of an HPIV outbreak occurring in Korea during 2006, genetic analysis of 269 cell culture isolates from HPIV-infected children, was conducted using nested reverse transcription-PCR (RT-PCR). HPIV-1 was detected in 70.3% of tested samples (189/269). The detection rate of HPIV-2 and HPIV-3 was 1.5% (4/269) and 9.3% (25/269), respectively. Mixed HPIV-1, -2 and -3 infections were detected in 19.0% (51/269): HPIV-1 and HPIV-2 in 15, HPIV-1 and HPIV-3 in 26, HPIV-2 and HPIV-3 in 6, and HPIV-1, -2 and -3 in 4. Of these positive samples for three different types HIPV-1, -2, and -3, two each representative strains were selected, the full length of hemagglutinin-neuraminidase (HN) gene for HPIV was amplified by RT-PCR, and sequenced. Multiple alignment analysis, based on reference sequence of HPIV-1, -2, and -3 strains available in GenBank, showed that the identity of nucleotide and deduced amino acid sequences was 92.4-97.6% and 92.7-97.9%, respectively, for HPIV-1, 88.5-99.8% and 88.6-100% for HPIV-2, and 96.3-99.5% and 95.0-99.3% for HPIV-3, respectively. Phylogenetic analysis showed that HPIV-1, -2, and -3 strains identified in this study were closely related among the strains in the same type with no significant genetic variability. These results show that HPIV of multiple imported sources was circulating in Korea.

Impact of both ends of the hemoglobin range on clinical outcomes in acute ischemic stroke.

BACKGROUND AND PURPOSE: Although both ends of the hemoglobin range may negatively influence clinical outcomes in acute ischemic stroke, most studies have examined the linear relationship or focused on the lower end of the range. Furthermore, it is unclear whether hemoglobin concentrations at different time points during hospitalization correlate with clinical outcomes in the same manner. METHODS: We identified 2681 consecutive patients with acute ischemic stroke from a prospective stroke registry database and grouped them into hemoglobin concentration quintiles using the following 5 indices: initial, nadir, time-averaged, discharge hemoglobin, and hemoglobin drop. To examine the effect of both ends of hemoglobin range, the third quintile was selected as a reference category except for hemoglobin drop, for which the first quintile was used. As outcome variables, 3-month modified Rankin Scale as an ordinal scale and 3-month mortality were used. RESULTS: With respect to higher modified Rankin Scale scores, the adjusted odds ratios and 95% confidence intervals of the first quintiles of initial, nadir, time-averaged, and discharge hemoglobin were 1.74 (1.31-2.31), 2.64 (2.09-3.33), 1.81 (1.42-2.30), and 1.65 (1.29-2.13), respectively. The opposite ends of these hemoglobin indices were not significantly associated. The adjusted odds ratio of the fifth quintile of hemoglobin drop (greatest hemoglobin drop) was 2.09 (1.51-2.89). The mortality analysis showed similar results except for initial hemoglobin. CONCLUSIONS: In acute ischemic stroke, poor outcome was related to the lower but not the higher end of the hemoglobin range, regardless of when and how hemoglobin concentrations were measured.

Validation of FLAIR hyperintense lesions as imaging biomarkers to predict the outcome of acute stroke after intra-arterial thrombolysis following intravenous tissue plasminogen activator.

BACKGROUND: Intravenous tissue plasminogen activator (tPA) given within 4.5 h of symptom onset is accepted as the standard treatment of ischemic stroke. Persistent occlusion of cerebral arteries despite intravenous thrombolysis and unremitting neurologic deficits lead us to consider additional intra-arterial approaches. The aim of this study was to elucidate the potential of fluid-attenuated inversion recovery (FLAIR) MRI performed during or immediately after intravenous thrombolysis for predicting clinical outcomes of subsequent intra-arterial thrombolysis. METHODS: With a prospective stroke registry database of patients hospitalized in our institution from January 2004 to February 2010, we identified ischemic stroke patients with the following conditions: (1) presentation within 2.5 h of onset, (2) treated with intravenous tPA based on brain CT, (3) persistent occlusion on subsequent MRI/MR angiography, including a FLAIR sequence, and (4) eventually treated with intra-arterial thrombolysis. Demographic, clinical and laboratory findings including initial National Institutes of Health Stroke Scale (NIHSS), follow-up NIHSS at the 7th day or discharge, modified Rankin scale (mRS) score at 3 months, and symptomatic hemorrhagic transformation were captured. FLAIR images were reviewed by 2 investigators blinded to clinical information independently and dichotomized into the absence and presence of FLAIR change within the diffusion-restriction lesions. RESULTS: Of the 57 patients who met these conditions, FLAIR-hyperintense lesions (FHL) were observed in 32 (56.1%). The FHL-negative group was 69.1 ± 12.1 years old on average and the FHL-positive group 67.3 ± 11.0 years old. In both groups, hypertension was the most common vascular risk factor, cardioembolic stroke was the most common subtype, and distal middle cerebral artery was the most common site of occlusion. The incidence of symptomatic hemorrhagic transformation was 4.0% in the FHL-negative group and 9.4% in the FHL-positive group (p = 0.62). NIHSS scores of 0-1 on the 7th day of hospitalization or at discharge were observed in 36% of the FHL-negative group and in 9.4% of the FHL-positive group; mRS scores of 0-1 at 3 months was 32% in the FHL-negative group and 21% in the FHL-positive group. An ordinal logistic regression analysis showed that the presence of FHL was associated with higher 7-day NIHSS scores (adjusted for relevant covariates) but not with higher 3-month mRS scores. CONCLUSIONS: This study suggests that the FHL might be used as imaging biomarker to predict outcomes for additional intra-arterial thrombolysis in patients treated with intravenous tPA.

Is aortic atherothrombotic disease detected using multidetector-row CT associated with an increased risk of early ischemic lesion recurrence after acute ischemic stroke?

BACKGROUND AND PURPOSE: Multidetector-row CT (MDCT) is emerging as a new tool for diagnosing aortic atherothrombotic disease (AAD). We elucidated whether MDCT-detected AAD is associated with an increased risk of early ischemic lesion recurrence on diffusion-weighted MRI after ischemic stroke. METHODS: A consecutive series of patients with acute ischemic stroke confirmed using diffusion-weighted MRI who were hospitalized within 48 hours after symptom onset and underwent MDCT were identified in a prospective stroke registry database. AAD on MDCT was defined as the presence of plaque formation that was noncalcified and ≥4 mm thick, ulcerative, or soft and thrombosed (vulnerable) in the proximal aortic arch. Ischemic lesion recurrence on diffusion-weighted MRI was defined as the occurrence of any new lesion separate from the index lesion on follow-up diffusion-weighted MRI performed within 14 days after symptom onset. RESULTS: A total of 138 patients was selected. MDCT detected AAD in 24 of 138 (17.4%); ≥4 mm thickness in 17 of 138 (12.3%); ulcerated plaque in 20 of 138 (14.5%); and vulnerable plaque in 16 of 138 (11.6%). With respect to diffusion-weighted MRI lesion recurrence, the crude ORs (95% CIs) were as follows: AAD, 3.56 (1.43-8.89); vulnerable plaque, 3.21 (1.11-9.30); ulcerated plaque, 3.37 (1.27-8.95); and ≥4 mm thickness of the noncalcified plaque, 4.23 (1.11-16.19). These results remained significant after adjustments for potential confounders were made. CONCLUSIONS: This study shows that AAD detected by MDCT increases the risk of early ischemic lesion recurrence after acute ischemic stroke, thus supporting the role of MDCT in diagnosing AAD and assessing its contribution to recurrence.

A methionine-based turn-on chemical sensor for selectively monitoring Hg2+ ions in 100% aqueous solution.

Dansyl-labeled methionine is synthesized by solid-phase synthesis, and found to be a highly sensitive and selective sensor for Hg(2+). The sensor sensitively detects Hg(2+) ions in aqueous solution by a turn-on response; however, the sensor detects Hg(2+) ions by a turn-off response in organic and mixed aqueous-organic solutions. We investigated the binding stoichiometry, binding constant, and binding mode of the sensor under various solvent conditions. In 100% aqueous solution, 2 : 1 complexation of the sensor with Hg(2+) ions is more favorable than 1 : 1 complexation, whereas the sensor preferentially forms a 1 : 1 complex in 100% CH(3)CN or in 50% CH(3)CN-aqueous solutions. Results reveal that the stoichiometry of the sensor-Hg(2+) complex plays an important role in the type of response to Hg(2+) ions, and that 2 : 1 complexation is required for a turn-on response to Hg(2+) ions in aqueous solution.

Delayed Lesions on Diffusion-Weighted Imaging in Initially Lesion-Negative Stroke Patients.

BACKGROUND AND PURPOSE: Lesions on diffusion-weighted imaging (DWI) occasionally appear on follow-up magnetic resonance imaging (MRI) among initially DWI-negative but clinically suspicious stroke patients. We established the prevalence of positive conversion in DWI-negative stroke and determined the clinical factors associated with it. METHODS: This retrospective, observational, single-center study included 5,271 patients hospitalized due to stroke/transient ischemic attack (TIA) in a single university hospital during 2010 to 2017. Patients without initial DWI lesions underwent follow-up DWI imaging as a routine practice. Adjusted hazard ratios (aHRs) for recurrent stroke risk according to positive conversion were determined using Cox proportional hazard regression. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for positive conversion among initially DWI-negative patients were estimated. RESULTS: In total, 694 (13.2%) patients (mean±standard deviation age, 62.9±13.7 years; male, 404 [58.2%]) were initially DWI-negative. Among them, 22.5% had positive-conversion on follow-up DWI. Positive conversion was associated with a higher risk of recurrent stroke (aHR, 3.12; 95% CI, 1.56 to 6.26). Early neurologic deterioration (aOR, 15.1; 95% CI, 5.71 to 47.66), atrial fibrillation (aOR, 6.17; 95% CI, 3.23 to 12.01), smoking (aOR, 3.76; 95% CI, 2.19 to 6.63), pre-stroke dependency (aOR, 1.62; 95% CI, 1.15 to 2.27), objective hemiparesis (aOR, 4.39; 95% CI, 1.90 to 10.32), longer symptom duration (aOR, 2.17; 95% CI, 1.57 to 3.08), high cholesterol (aOR, 4.70; 95% CI, 1.78 to 12.77), National Institutes of Health Stroke Scale score (aOR, 1.44; 95% CI, 1.08 to 1.91), and high systolic blood pressure (aOR, 1.01; 95% CI, 1.00 to 1.02) were associated with a higher incidence of lesions with delayed appearance. Regarding the location of lesions on follow-up DWI, 34.6% and 21.2% were in the cortex and brainstem, respectively. CONCLUSIONS: In DWI-negative stroke/TIA, positive conversion is associated with a higher risk of recurrent stroke. DWI-negative stroke with factors related to positive conversion may require follow-up MRI for a definitive diagnosis.

Differential effect of previous antiplatelet use on stroke severity according to stroke mechanism.

BACKGROUND AND PURPOSE: The effect of previous antiplatelet use on stroke severity is controversial. We assume that this controversy is attributable to its difference according to the stroke mechanism. METHODS: Using a prospective stroke registry, patients who were hospitalized because of ischemic stroke and had relevant lesions on MRI were selected. Patients who were using anticoagulants or whose stroke subtype was categorized as stroke of other determined etiology or undetermined etiology were excluded. Baseline stroke severity was measured using the National Institutes of Health Stroke Scale scores at presentation and was compared between no previous antiplatelet users and previous antiplatelet users with stratification by stroke subtypes. RESULTS: Among the 1622 patients, a total of 490 (30.2%) patients reported use of an antiplatelet within 1 week of stroke onset. The baseline National Institutes of Health Stroke Scale score showed no difference between the nonantiplatelet and antiplatelet groups by crude comparison. However, the interaction between previous antiplatelet use and stroke subtype was significant (P=0.023) in a multivariable analysis; when the study subjects were stratified by stroke subtype, the difference in baseline National Institutes of Health Stroke Scale between the nonantiplatelet and platelet groups was significant in the large artery atherothrombosis group but not in those with cardioembolism and small-vessel occlusion before and after adjustments. CONCLUSIONS: Our study suggests that the reduction of initial stroke severity in the previous antiplatelet users may differ by stroke mechanism.

The significance of blood pressure variability for the development of hemorrhagic transformation in acute ischemic stroke.

BACKGROUND AND PURPOSE: Elevated blood pressure (BP) is commonly observed in acute ischemic stroke and is known to be associated with hemorrhagic transformation (HT). However, the effect of BP variability on the development of HT is not known well. METHODS: A consecutive series of patients with acute ischemic stroke, who were hospitalized within 24 hours of onset and showed no HT on initial gradient echo MRI, were enrolled in this study. BP measurements during the first 72 hours were obtained, and BP variability of each patient was described using various summary parameters: SD, maximum (max), minimum (min), difference between max and min (max-min), average squared difference between successive measurements (sv), and maximum sv (svmax). RESULTS: Of 792 patients meeting the eligibility criteria, 70 (8.8%) developed HT. Among BP variability parameters categorized into quartiles, SBP(max), SBP(min), SBP(max-min), SBP(svmax), DBP(SD), DBP(max), DBP(min), DBP(max-min), and DBP(svmax) were significantly associated with HT independent of mean SBP, age, interval from onset to arrival, initial stroke severity, diabetes mellitus, stroke subtype, thrombolysis, initial glucose, and total cholesterol (P<0.05 on likelihood ratio test of trend). The analyses about the interaction between thrombolysis and variability parameters showed that the effects of BP variability on the development of HT did not differ by whether patients received thrombolysis or not. CONCLUSIONS: Our study suggests that we may consider not only the absolute level of BP but also its variability to prevent hemorrhagic transformation.

Relationship between blood pressure and outcome changes over time in acute ischemic stroke.

OBJECTIVE: To evaluate whether the relationship between systolic blood pressure (SBP) and stroke outcome varies during the acute stage of ischemic stroke as a function of the elapsed time after stroke onset. METHODS: Patients who were hospitalized due to ischemic stroke within 6 hours of onset were retrospectively analyzed. SBP data were collected at 8 time points (1, 2, 4, 8, 16, 24, 48, and 72 hours after onset). The primary functional outcome measure was a poor outcome, defined as a modified Rankin Scale score of >2 at 3 months after stroke. Linear and quadratic models were constructed at each time point to assess relationships between SBP and outcome. RESULTS: Of the 2,546 patients, 728 (28.6%) had a poor outcome. SBP, as either a linear or quadratic term, had a significant effect on functional outcome, except at 4 hours after onset. For the initial 2 hours after onset, SBP had nonlinear U-shaped relationships with functional outcome, and patients with SBP of approximately 165 mm Hg were the least likely to have a poor outcome. Quadratic models exhibited a significantly better model fit. For 8-24 hours postonset, SBP exhibited linear relationships with functional outcome. For 48-72 hours postonset, SBP exhibited a J-shaped relationship with functional outcome, and the predicted probability of poor outcome was the lowest in patients with SBP of approximately 125 mm Hg. These relationships were relatively consistent across various sensitivity analyses. CONCLUSION: This study revealed that the relationship between SBP and functional outcome may depend on elapsed time from stroke onset.

Blood pressure variability in subacute stage and risk of major vascular events in ischemic stroke survivors.

BACKGROUND: We aimed to investigate whether blood pressure (BP) in the subacute stage of ischemic stroke affects subsequent vascular events after acute ischemic stroke. METHODS: From a prospective stroke registry database, consecutive ischemic stroke patients arriving within 48 h of onset were identified. The mean and SD of SBP per patient (SBPmean and SBPSD) in the subacute stage (from 72 h of onset to discharge), were calculated. Primary outcome was a composite of stroke, myocardial infarction and vascular death that occurred within 1 year after hospital discharge. A Cox proportional hazards model was applied to elucidate whether the increase of SBPmean and SBPSD would increase the hazards of the primary outcome. RESULTS: Of 4415 patients (age, 66.7 ±â€Š13.2 years; men, 69.5%), mean ±â€ŠSD of SBPmean and SBPSD in the subacute stage was 137.3 ±â€Š15.4 and 13.3 ±â€Š3.9 mmHg, respectively. Primary outcome events occurred in 6.9% during the first year after stroke. There was a significant dose-response relationship between the SBPSD and the risk of the primary outcome (P = 0.004), but not between SBPmean and the risk (P = 0.78). Interpolating the change of adjusted hazard ratio using restricted cubic spine function suggested an existence of a threshold effect of SBPSD and a U-shaped relationship of SBPmean for the composite event. CONCLUSION: This study shows that BP variability but not mean BP in the subacute stage of ischemic stroke may increase 1-year risk of major vascular events in patients surviving its acute stage.

CT Angiography of Collateral Vessels and Outcomes in Endovascular-Treated Acute Ischemic Stroke Patients.

BACKGROUND AND PURPOSE: Measuring the extent of the collateral blood vessels using computed tomography (CT) angiography source images may promote tissue survival and functional gain in acute ischemic stroke patients who are candidates for endovascular recanalization treatment. METHODS: Of 5,558 acute stroke patients registered in a prospective clinical stroke registry, 104 met the selection criteria of endovascular recanalization treatment for internal cerebral artery or middle cerebral artery main-stem (M1) occlusions and presented for treatment ≤4 hours after the event. Using CT angiography source images, two independent and blinded reviewers measured the extent of collateral circulations at four regions, with good interrater reliability. The functional recovery at 3 months after stroke was used as an outcome variable. RESULTS: Cases with a sufficient collateral circulation at the Sylvian fissure showed significantly increased likelihood of having a modified Rankin Scale score of ≤2 at 3 months after stroke (adjusted odds ratio=3.03, 95% confidence interval=1.19-7.73, p=0.02), but the association became nonsignificant after adding the infarct volume to the model (p=0.65). The association between leptomeningeal convexity collaterals and functional recovery was no longer significant after adjusting for the infarct volume (p=0.28). The natural indirect effect of infarct volume on functional recovery was significant for both the Sylvian fissure (p=0.03) and leptomeningeal convexity (p=0.02) collaterals. CONCLUSIONS: The extent of collateral circulation at the Sylvian fissure was significantly associated with functional recovery, which may be mediated via the volume of the final infarction.

Left Ventricular Diastolic Dysfunction in Ischemic Stroke: Functional and Vascular Outcomes.

BACKGROUND AND PURPOSE: Left ventricular (LV) diastolic dysfunction, developed in relation to myocardial dysfunction and remodeling, is documented in 15%-25% of the population. However, its role in functional recovery and recurrent vascular events after acute ischemic stroke has not been thoroughly investigated. METHODS: In this retrospective observational study, we identified 2,827 ischemic stroke cases with adequate echocardiographic evaluations to assess LV diastolic dysfunction within 1 month after the index stroke. The peak transmitral filling velocity/mean mitral annular velocity during early diastole (E/e') was used to estimate LV diastolic dysfunction. We divided patients into 3 groups according to E/e' as follows: <8, 8-15, and ≥15. Recurrent vascular events and functional recovery were prospectively collected at 3 months and 1 year. RESULTS: Among included patients, E/e' was 10.6±6.4: E/e' <8 in 993 (35%), 8-15 in 1,444 (51%), and ≥15 in 378 (13%) cases. Functional dependency or death (modified Rankin Scale score ≥2) and composite vascular events were documented in 1,298 (46%) and 187 (7%) patients, respectively, at 3 months. In multivariable analyses, ischemic stroke cases with E/e' ≥15 had increased odds of functional dependence or death at 3 months (adjusted OR [95% CI]: 1.73 [1.27-2.35]) or 1 year (1.47 [1.06-2.06]) and vascular events within 1 year (1.65 [1.08-2.51]). Subgroups with normal ejection fraction or sinus rhythm exhibited a similar overall pattern and direction. CONCLUSIONS: LV diastolic dysfunction was associated with poor functional outcomes and composite vascular events up to 1 year.

Stroke outcomes with use of antithrombotics within 24 hours after recanalization treatment.

OBJECTIVE: To compare clinical outcomes of patients who received early initiation (<24 hours) of antithrombotics with those who received standard management (antithrombotics administered ≥24 hours). METHODS: A total of 712 patients who had an acute ischemic stroke and underwent IV or endovascular (intra-arterial [IA]) recanalization between July 2007 and March 2015 were selected from a prospective clinical registry. Antithrombotics were initiated by an individual clinical decision. We systemically gathered information regarding the exact timing of antithrombotic initiation from a database of the electronic barcode medication administration system. RESULTS: The recanalization treatment cases included in this study comprised 34% (n = 243) IV only, 32% (n = 229) IA only, and 34% (n = 240) combined IV-IA strategies. Antithrombotics were administered within 24 hours in 64% (n = 456) of the patients. Earlier initiation of antithrombotics was associated with decreased odds of having any hemorrhages (adjusted odds ratio 0.56; 95% confidence interval 0.35-0.89), but was not associated with symptomatic hemorrhages (0.85; 0.35-2.10) or modified Rankin Scale scores of 0-1 at 3 months after stroke (1.09; 0.75-1.59). Ultra-early initiation (<12 hours) did not increase the odds of hemorrhagic transformation (0.26; 0.12-0.52). The effects of earlier antithrombotics on the clinical outcomes were not significantly modified by the modality of recanalization treatment. CONCLUSIONS: In our retrospective analysis of a prospective registry, early antithrombotic (within 24 hours after initiation) administration did not increase hemorrhages after recanalization treatment. Early antithrombotic therapy may be advantageous for a subset of stroke patients despite the current guidelines.

Blood pressure variability and the development of early neurological deterioration following acute ischemic stroke.

OBJECTIVES: Early neurological deterioration (END) is a common condition associated with poor outcome after acute ischemic stroke. We studied association between blood pressure (BP) variability and development of END. METHODS: In this retrospective observational study, we studied a consecutive series of patients hospitalized for acute ischemic stroke within 24 h of onset. The primary outcome of interest was the development of END according to predefined criteria within the first 72 h of stroke onset. During this period, the mean, maximum (max), and minimum (min) values for the SBP and DBP were measured. The following parameters of BP variability were calculated for the SBP and DBP: the difference between the maximum and minimum (max-min), the SD, and the coefficient of variation. RESULTS: Of the 1161 patients enrolled in the study (mean age, 67.5 ±â€Š13.3 years; 59.6% men), 210 (18.1%) developed END. All of the BP variability parameters were linearly associated with END independent of mean BP and potential clinical variables (P values < 0.05 on likelihood ratio tests for trend), except for SBPmax-min. Among the other BP parameters, SBPmean, SBPmax, DBPmax, and DBPmin were independently associated with END. After adjustments for potential confounders, the odds for END increased 14-21% with each increase of one standard deviation in the BP variability parameter. CONCLUSION: BP variability is independently and linearly associated with the development of neurologic deterioration in acute stage of ischemic stroke.

Trial of ORG 10172 in Acute Stroke Treatment (TOAST) classification and vascular territory of ischemic stroke lesions diagnosed by diffusion-weighted imaging.

BACKGROUND: The association between the location and the mechanism of a stroke lesion remains unclear. A diffusion-weighted imaging study may help resolve this lack of clarity. METHODS AND RESULTS: We studied a consecutive series of 2702 acute ischemic stroke patients whose stroke lesions were confirmed by diffusion-weighted imaging and who underwent a thorough etiological investigation. The vascular territory in which an ischemic lesion was situated was identified using standard anatomic maps of the dominant arterial territories. Stroke subtype was based on the Trial of ORG 10172 in Acute Stroke Treatment, or TOAST, classification. Large-artery atherosclerosis (37.3%) was the most common stroke subtype, and middle cerebral artery (49.6%) was the most frequently involved territory. Large-artery atherosclerosis was the most common subtype for anterior cerebral, middle cerebral, vertebral, and anterior and posterior inferior cerebellar artery territory infarctions. Small vessel occlusion was the leading subtype in basilar and posterior cerebral artery territories. Cardioembolism was the leading cause in superior cerebellar artery territory. Compared with carotid territory stroke, vertebrobasilar territory stroke was more likely to be caused by small vessel occlusion (21.4% versus 30.1%, P<0.001) and less likely to be caused by cardioembolism (23.2% versus 13.8%, P<0.001). Multiple-vascular-territory infarction was frequently caused by cardioembolism (44.2%) in carotid territory and by large-artery atherosclerosis (52.1%) in vertebrobasilar territory. CONCLUSIONS: Information on vascular territory of a stroke lesion may be helpful in timely investigation and accurate diagnosis of stroke etiology.