The National Institutes of Health Stroke Scale is comparable to the ICH score in predicting outcomes in spontaneous acute intracerebral hemorrhage.

Background: Validating the National Institutes of Health NIH Stroke Scale (NIHSS) as a tool to assess deficit severity and prognosis in patients with acute intracerebral hemorrhage would harmonize the assessment of intracerebral hemorrhage (ICH) and acute ischemic stroke (AIS) patients, enable clinical use of a readily implementable and non-imaging dependent prognostic tool, and improve monitoring of ICH care quality in administrative datasets. Methods: Among randomized trial ICH patients, the relation between NIHSS scores early after Emergency Department arrival and 3-month outcomes of dependency or death (modified Rankin Scale, mRS 3-6) and case fatality was examined. NIHSS predictive performance was compared to a current standard prognostic scale, the intracerebral hemorrhage score (ICH score). Results: Among the 384 patients, the mean age was 65 (±13), with 66% being male. The median NIHSS score was 16 (interquartile range (IQR) 9-25), the mean initial hematoma volume was 29 mL (±38), and the ICH score median was 1 (IQR 0-2). At 3 months, the mRS had a median of 4 (IQR 2-6), with dependency or death occurring in 70% and case fatality in 26%. The NIHSS and ICH scores were strongly correlated (r = 0.73), and each was strongly correlated with the 90-day mRS (NIHSS, r = 0.61; ICH score, r = 0.62). The NIHSS performed comparably to the ICH score in predicting both dependency or death (c = 0.80 vs. 0.80, p = 0.83) and case fatality (c = 0.78 vs. 0.80, p = 0.29). At threshold values, the NIHSS predicted dependency or death with 74.1% accuracy (NIHSS 17.5) and case fatality with 75.0% accuracy (NIHSS 18.5). Conclusion: The NIHSS forecasts 3-month functional and case fatality outcomes with accuracy comparable to the ICH Score. Widely documented in routine clinical care and administrative data, the NIHSS can serve as a valuable measure for clinical prognostication, therapy development, and case-mix risk adjustment in ICH patients.Clinical trial registrationClinicaltrials.gov, NCT00059332.

Corrigendum: Staged use of ordinal and linear disability scales: a practical approach to granular assessment of acute stroke outcome.

[This corrects the article DOI: 10.3389/fneur.2023.1174686.].

Modified Rankin Scale Disability Status at Day 4 Poststroke is an Informative Predictor of Long-Term Day 90 Outcome.

Background: Long-term disability after stroke is standardly assessed 3 months post-onset, using the modified Rankin Scale (mRS). The value of an early, day 4 mRS assessment for projecting the 3-month disability outcome has not been formally investigated. Methods: In this cohort of patients with acute cerebral ischemia and intracranial hemorrhage, we analyzed day 4 and day 90 mRS assessments in the NIH Field Administration of Stroke Therapy- Magnesium (FAST-MAG) Phase 3 trial. The performance of day 4 mRS, alone and as part of multivariate models, in predicting day 90 mRS was assessed using correlation coefficients, percent agreement, and the kappa statistics. Results: Among the 1573 acute cerebrovascular disease (ACVD) patients, 1206 (76.7%) had acute cerebral ischemia (ACI), while 367 (23.3%) had intracranial hemorrhage. Among all 1573 ACVD patients, day 4 mRS and day 90 mRS correlated strongly, Spearman's rho=0.79, in unadjusted analysis with weighted kappa of 0.59. For dichotomized outcomes, simple carry-forward of the day 4 mRS performed fairly well in agreeing with day 90 mRS: mRS 0-1 (k=0.67), 85.4%; mRS 0-2 (k=0.59), 79.5%; fatal outcome, 88.3% (k=0.33). Correlations of 4d and 90d mRS were stronger for ACI than ICH patients, 0.76 vs 0.71. Conclusions: In this acute cerebrovascular disease patient cohort, assessment of global disability performed on day 4 is highly informative regarding long-term, 3-month mRS disability outcome, alone, and even more strongly in combination with baseline prognostic variables. The day 4 mRS is a useful measure for imputing the final patient disability outcome in clinical trials and quality improvement programs.

Staged use of ordinal and linear disability scales: a practical approach to granular assessment of acute stroke outcome.

Background: The modified Rankin Scale (mRS) assessment of global disability is the most common primary endpoint in acute stroke trials but lacks granularity (7 broad levels) and is ordinal (scale levels unknown distances apart), which constrains study power. Disability scales that are linear and continuous may better discriminate outcomes, but computerized administration in stroke patients is challenging. We, therefore, undertook to develop a staged use of an ordinal followed by a linear scale practical to use in multicenter trials. Methods: Consecutive patients undergoing 3-month final visits in the NIH FAST-MAG phase 3 trial were assessed with the mRS followed by 15 mRS level-specific yes-no items of the Academic Medical Center Linear Disability Score (ALDS), a linear disability scale derived using item response theory. Results: Among 55 patients, aged 71.2 (SD ± 14.2), 67% were men and the entry NIHSS was 10.7 (SD ± 9.5). At 90 days, the median mRS score was 3 (IQR, 1-4), and the median ALDS score was 78.8 (IQR, 3.3-100). ALDS scores correlated strongly with 90 days outcome measures, including the Barthel Index (r = 0.92), NIHSS (r = 0.87), and mRS (r = 0.94). ALDS scores also correlated modestly with entry NIHSS (r = 0.38). At 90 days, the ALDS showed greater scale granularity than the mRS, with fewer patients with identical values, 1.9 (SD ± 3.2) vs. 8.0 (SD ± 3.6), p < 0.001. When treatment effect magnitudes were small to moderate, projected trial sample size requirements were 2-12-fold lower when the ALDS rather than the mRS was used as the primary trial endpoint. Conclusion: Among patients enrolled in an acute neuroprotective stroke trial, the ALDS showed strong convergent validity and superior discrimination characteristics compared with the modified Rankin Scale and increased projected trial power to detect clinically meaningful treatment benefits.

Essential information for neurorecovery clinical trial design: trajectory of global disability in first 90 days post-stroke in patients discharged to acute rehabilitation facilities.

BACKGROUND: Many stroke recovery interventions are most beneficial when started 2-14d post-stroke, a time when patients become eligible for inpatient rehabilitation facilities (IRF) and neuroplasticity is often at its peak. Clinical trials focused on recovery need to expand the time from this plasticity to later outcome timepoints. METHODS: The disability course of patients with acute ischemic stroke (AIS) and intracranial hemorrhage (ICH) enrolled in Field Administration of Stroke Therapy Magnesium (FAST-MAG) Trial with moderate-severe disability (modified Rankin Scale [mRS] 3-5) on post-stroke day4 who were discharged to IRF 2-14d post-stroke were analyzed. RESULTS: Among 1422 patients, 446 (31.4%) were discharged to IRFs, including 23.6% within 2-14d and 7.8% beyond 14d. Patients with mRS 3-5 on day4 discharged to IRFs between 2-14d accounted for 21.7% (226/1041) of AIS patients and 28.9% (110/381) of ICH patients, (p < 0.001). Among these AIS patients, age was 69.8 (± 12.7), initial NIHSS median 8 (IQR 4-12), and day4 mRS = 3 in 16.4%, mRS = 4 in 50.0%, and mRS = 5 in 33.6%. Among these ICH patients, age was 62.4 (± 11.7), initial NIHSS median 9 (IQR 5-13), day 4 mRS = 3 in 9.4%, mRS = 4 in 45.3%, and mRS = 5 in 45.3% (p < 0.01 for AIS vs ICH). Between day4 to day90, mRS improved ≥ 1 levels in 72.6% of AIS patients vs 77.3% of ICH patients, p = 0.3. For AIS, mRS improved from mean 4.17 (± 0.7) to 2.84 (± 1.5); for ICH, mRS improved from mean 4.35 (± 0.7) to 2.75 (± 1.3). Patients discharged to IRF beyond day14 had less improvement on day90 mRS compared with patients discharged between 2-14d. CONCLUSIONS: In this acute stroke cohort, nearly 1 in 4 patients with moderate-severe disability on post-stroke day4 were transferred to IRF within 2-14d post-stroke. ICH patients had nominally greater mean improvement on mRS day90 than AIS patients. This course delineation provides a roadmap for future rehabilitation intervention studies.

Circadian variation in stroke onset: Differences between ischemic and hemorrhagic stroke and weekdays versus weekends.

OBJECTIVES: To delineate diurnal variation onset distinguishing ischemic from hemorrhagic stroke, wake from sleep onset, and weekdays from weekends/holidays. MATERIALS AND METHODS: We analyzed patients enrolled in the FAST-MAG trial of field-initiated neuroprotective agent in patients with hyperacute stroke within 2h of symptoms onset. Stroke onset times were analyzed in 1h, 4h, and 12h time blocks throughout the 24h day-night cycle. Patient demographic, clinical features, stroke severity, and prehospital workflow were evaluated for association with onset times. RESULTS: Among 1615 acute cerebrovascular disease patients, final diagnoses were acute cerebral ischemia in 76.5% and Intracerebral hemorrhage in 23.5%. Considering all acute cerebrovascular disease patients, frequency of wake onset times showed a bimodal pattern, with peaks on onsets at 09:00-13:59 and 17:00-18:59 and early morning (00:00-05:59) onset in only 3.8%. Circadian rhythmicity differed among stroke subtypes: in acute cerebral ischemia, a single broad plateau of elevated incidences was seen from 10:00-21:59; in Intracerebral hemorrhage, bimodal peaks occurred at 09:00 and 19:00. The ratio of Intracerebral hemorrhage to acute cerebral ischemia occurrence was highest in early morning, 02:00-06:59. Marked weekday vs weekends pattern variation was noted for acute cerebral ischemia, with a broad plateau between 09:00 and 21:59 on weekdays but a unimodal peak at 14:00-15:59 on weekends. CONCLUSIONS: Wake onset of acute cerebrovascular disease showed a marked circadian variation, with distinctive patterns of a broad elevated plateau among acute cerebral ischemia patients; a bimodal peak among intracerebral hemorrhage patients; and a weekend change in acute cerebral ischemia pattern to a unimodal peak.

Neurologic Improvement in Acute Cerebral Ischemia: Frequency, Magnitude, Predictors, and Clinical Outcomes.

BACKGROUND AND OBJECTIVES: Investigations of rapid neurologic improvement (RNI) in patients with acute cerebral ischemia (ACI) have focused on RNI occurring after hospital arrival. However, with stroke routing decisions and interventions increasingly migrating to the prehospital setting, there is a need to delineate the frequency, magnitude, predictors, and clinical outcomes of patients with ACI with ultra-early RNI (U-RNI) in the prehospital and early postarrival period. METHODS: We analyzed prospectively collected data of the prehospital Field Administration of Stroke Therapy-Magnesium (FAST-MAG) randomized clinical trial. Any U-RNI was defined as improvement by 2 or more points on the Los Angeles Motor Scale (LAMS) score between the prehospital and early post-emergency department (ED) arrival examinations and classified as moderate (2-3 point) or dramatic (4-5 point) improvement. Outcome measures included excellent recovery (modified Rankin Scale [mRS] score 0-1) and death by 90 days. RESULTS: Among the 1,245 patients with ACI, the mean age was 70.9 years (SD 13.2); 45% were women; the median prehospital LAMS was 4 (interquartile range [IQR] 3-5); the median last known well to ED-LAMS time was 59 minutes (IQR 46-80 minutes), and the median prehospital LAMS to ED-LAMS time was 33 minutes (IQR 28-39 minutes). Overall, any U-RNI occurred in 31%, moderate U-RNI in 23%, and dramatic U-RNI in 8%. Any U-RNI was associated with improved outcomes, including excellent recovery (mRS score 0-1) at 90 days 65.1% (246/378) vs 35.4% (302/852), p < 0.0001; decreased mortality by 90 days 3.7% (14/378) vs 16.4% (140/852), p < 0.0001; decreased symptomatic intracranial hemorrhage 1.6% (6/384) vs 4.6% (40/861), p = 0.0112; and increased likelihood of being discharged home 56.8% (218/384) vs 30.2% (260/861), p < 0.0001. DISCUSSION: U-RNI occurs in nearly 1 in 3 ambulance-transported patients with ACI and is associated with excellent recovery and decreased mortality at 90 days. Accounting for U-RNI may be useful for routing decisions and future prehospital interventions. TRIAL REGISTRATION INFORMATION: clinicaltrials.gov. Unique identifier: NCT00059332.

Effect of Magnesium on Deterioration and Symptomatic Hemorrhagic Transformation in Cerebral Ischemia: An Ancillary Analysis of the FAST-MAG Trial.

BACKGROUND: Magnesium (Mg) is a neuroprotectant in preclinical models. Lower serum Mg levels have been associated with symptomatic hemorrhagic transformation (HT) in patients with ischemic stroke. Early treatment of acute ischemic stroke with Mg may reduce rates of symptomatic HT. METHODS: In this post hoc study of the Field Administration of Stroke Therapy Magnesium (FAST-MAG) trial, 1,245 participants with a diagnosis of cerebral ischemia received 20 g of Mg or placebo initiated in the prehospital setting. Posttreatment serum Mg level was measured for 809 participants. Cases of clinical deterioration, defined as worsening by ≥4 points on the National Institute of Health Stroke Scale (NIHSS), were imaged and evaluated for etiology. Symptomatic HT was defined as deterioration with imaging showing new hemorrhage. RESULTS: Clinical deterioration occurred in 187 and symptomatic HT in 46 of 1,245 cases of cerebral ischemia. Rates of deterioration and symptomatic HT were not significantly lower in those who received Mg (15.7% vs. 14.4%, p = 0.591; 2.8% vs. 4.6%, p = 0.281). In cases where serum Mg level was obtained posttreatment, lower serum Mg level (<1.7 mg/dL) was associated with significantly higher rates of deterioration and symptomatic HT (27.5% vs. 15.5%, p = 0.0261; 11.6% vs. 3.65%, p = 0.00819). CONCLUSIONS: Treatment with Mg did not significantly reduce rates of clinical deterioration or symptomatic HT. Future analysis should address whether treatment with Mg could have influenced the subgroup with low serum Mg at baseline.

Association Between Hyperacute Blood Pressure Variability and Hematoma Expansion After Intracerebral Hemorrhage: Secondary Analysis of the FAST-MAG Database.

BACKGROUND: Blood pressure variability (BPV) has emerged as a significant factor associated with clinical outcomes after intracerebral hemorrhage (ICH). Although hematoma expansion (HE) is associated with clinical outcomes, the relationship between BPV that encompasses prehospital data and HE is unknown. We hypothesized that BPV was positively associated with HE. METHODS: We analyzed 268 patients with primary ICH enrolled in the National Institutes of Health-funded Field Administration of Stroke Therapy-Magnesium (FAST-MAG) study who received head computed tomography or magnetic resonance imaging on arrival to the emergency department (ED) and repeat imaging within 6-48 h. BPV was calculated by standard deviation (SD) and coefficient of variation (CV) from prehospital data as well as systolic blood pressure (SBP) measurements taken on ED arrival, 15 min post antihypertensive infusion start, 1 h post maintenance infusion start, and 4 h after ED arrival. HE was defined by hematoma volume expansion increase > 6 mL or by 33%. Univariate logistic regression was used for presence of HE in quintiles of SD and CV of SBP for demographics and clinical characteristics. RESULTS: Of the 268 patients analyzed from the FAST-MAG study, 116 (43%) had HE. Proportions of patients with HE were not statistically significant in the higher quintiles of the SD and CV of SBP for either the hyperacute or the acute period. Presence of HE was significantly more common in patients on anticoagulation. CONCLUSIONS: Higher BPV was not found to be associated with occurrence of HE in the hyperacute or the acute period of spontaneous ICH. Further study is needed to determine the relationship.

Quantifying the amount of greater brain ischemia protection time with pre-hospital vs. in-hospital neuroprotective agent start.

The objective of this study is to quantify the increase in brain-under-protection time that may be achieved with pre-hospital compared with the post-arrival start of neuroprotective therapy among patients undergoing endovascular thrombectomy. In order to do this, a comparative analysis was performed of two randomized trials of neuroprotective agents: (1) pre-hospital strategy: Field administration of stroke therapy-magnesium (FAST-MAG) Trial; (2) in-hospital strategy: Efficacy and safety of nerinetide for the treatment of acute ischemic stroke (ESCAPE-NA1) Trial. In the FAST-MAG trial, among 1,041 acute ischemic stroke patients, 44 were treated with endovascular reperfusion therapy (ERT), including 32 treated with both intravenous thrombolysis and ERT and 12 treated with ERT alone. In the ESCAPE-NA1 trial, among 1,105 acute ischemic stroke patients, 659 were treated with both intravenous thrombolysis and ERT, and 446 were treated with ERT alone. The start of the neuroprotective agent was sooner after onset with pre-hospital vs. in-hospital start: 45 m (IQR 38-56) vs. 122 m. The neuroprotective agent in FAST-MAG was started 8 min prior to ED arrival compared with 64 min after arrival in ESCAPE-NA1. Projecting modern endovascular workflows to FAST-MAG, the total time of "brain under protection" (neuroprotective agent start to reperfusion) was greater with pre-hospital than in-hospital start: 94 m (IQR 90-98) vs. 22 m. Initiating a neuroprotective agent in the pre-hospital setting enables a faster treatment start, yielding 72 min additional brain protection time for patients with acute ischemic stroke. These findings provide support for the increased performance of ambulance-based, pre-hospital treatment trials in the development of neuroprotective stroke therapies.

Identifying acute ischemic stroke patients within the thrombolytic treatment window using deep learning.

BACKGROUND AND PURPOSE: Treatment of acute ischemic stroke is heavily contingent upon time, as there is a strong relationship between time clock and tissue progression. Work has established imaging biomarker assessments as surrogates for time since stroke (TSS), namely, by comparing signal mismatch between diffusion-weighted imaging (DWI) and fluid-attenuated inversion recovery (FLAIR) imaging. Our goal was to develop an automatic technique for determining TSS from imaging that does not require subspecialist radiology expertise. METHODS: Using 772 patients (66 ± 9 years, 319 women), we developed and externally evaluated a deep learning network for classifying TSS from MR images and compared algorithm predictions to neuroradiologist assessments of DWI-FLAIR mismatch. Models were trained to classify TSS within 4.5 hours and performance metrics with confidence intervals were reported on both internal and external evaluation sets. RESULTS: Three board-certified neuroradiologists' DWI-FLAIR mismatch assessments, based on majority vote, yielded a sensitivity of .62, a specificity of .86, and a Fleiss' kappa of .46 when used to classify TSS. The deep learning method performed similarly to radiologists and outperformed previously reported methods, with the best model achieving an average evaluation accuracy, sensitivity, and specificity of .726, .712, and .741, respectively, on an internal cohort and .724, .757, and .679, respectively, on an external cohort. CONCLUSION: Our model achieved higher generalization performance on external evaluation datasets than the current state-of-the-art for TSS classification. These results demonstrate the potential of automatic assessment of onset time from imaging without the need for expertly trained radiologists.

Improving Visualization Methods of Utility-Weighted Disability Outcomes for Stroke Trials.

Background: The modified Rankin Scale (mRS) is the most common endpoint in acute stroke trials, but its power is limited when analyzed dichotomously and its indication of effect size is challenging to interpret when analyzed ordinally. To address these issues, the utility-weighted-mRS (UW-mRS) has been developed as a patient-centered, linear scale. However, appropriate data visualizations of UW-mRS results are needed, as current stacked bar chart displays do not convey crucial utility-weighting information. Design/Methods: Two UW-mRS display formats were devised: (1) Utility Staircase charts, and (2) choropleth-stacked-bar-charts (CSBCs). In Utility Staircase displays, mRS segment height reflects the utility value of each mRS level. In CSBCs, mRS segment color intensity reflects the utility of each mRS level. Utility Staircase and CSBC figures were generated for 15 randomized comparisons of acute ischemic/hemorrhagic stroke therapies, including fibrinolysis, endovascular reperfusion, blood pressure moderation, and hemicraniectomy. Display accuracy in showing utility outcomes was assessed with the Tufte-lie-factor and ease-of-use assessed by formal ratings completed by a panel of 4 neurologists and emergency physicians and one nurse-coordinator. Results: The Utility Staircase and CSBC displays rapidly conveyed patient-centered valuation of trial outcome distributions not available in conventional ordinal stacked bar charts. Tufte-lie-factor (LF) scores indicated "substantial distortion" of utility-valued outcomes for 93% (14/15) of conventional stacked bar charts, vs. "no distortion" for all Utility Staircase and CSBC displays. Clinician ratings on the Figural Display Questionnaire indicated that utility information encoded in row height (Utility Staircase display) was more readily assimilated than that conveyed in segment hue intensity (CSBC), both superior to conventional stacked bar charts. Conclusions: Utility Staircase displays are an efficient graphical format for conveying utility weighted-modified Rankin Scale primary endpoint results of acute stroke trials, and choropleth-stacked-bar-charts a good alternative. Both are more accurate in depicting quantitative, health-related quality of life results and preferred by clinician users for utility results visualization, compared with conventional stacked bar charts.

Beyond the Golden Hour: Treating Acute Stroke in the Platinum 30 Minutes.

BACKGROUND: To emphasize treatment speed for time-sensitive conditions, emergency medicine has developed not only the concept of the golden hour, but also the platinum half-hour. Patients with acute stroke treated within the first half-hour of onset have not been previously characterized. METHODS: In this cohort study, we analyzed patients enrolled in the FAST-MAG (Field Administration of Stroke Therapy-Magnesium) trial, testing paramedic prehospital start of neuroprotective agent ≤2 hours of onset. The features of all acute cerebral ischemia, and intracranial hemorrhage patients with treatment starting at ≤30 m of last known well were compared with later-treated patients. RESULTS: Among 1680 patients, 203 (12.1%) received study agents within 30 minutes of last known well. Among platinum half-hour patients, median onset-to-treatment time was 28 minutes (interquartile range, 25-30), and final diagnoses were acute cerebral ischemia in 71.8% (ischemic stroke, 61.5%, TIA 10.3%); intracranial hemorrhage in 26.1%; and mimic in 2.5%. Clinical features among platinum half-hour patients were largely similar to later-treated patients and included age 69 (interquartile range, 57-79), 44.8% women, prehospital Los Angeles Motor Scale median 4 (3-5), and early-postarrival National Institutes of Health Stroke Scale deficit 8 (interquartile range, 3-18). Platinum half-hour acute cerebral ischemia patients did have more severe prehospital motor deficits and younger age; platinum half-hour intracranial hemorrhage patients had more severe motor deficits, were more often female, and less often of Hispanic ethnicity. Outcomes at 3 m in platinum half-hour patients were comparable to later-treated patients and included freedom-from-disability (modified Rankin Scale score, 0-1) in 35.5%, functional independence (modified Rankin Scale score, 0-2) in 53.2%, and mortality in 17.7%. CONCLUSIONS: Prehospital initiation permits treatment start within the platinum half-hour after last known well in a substantial proportion of acute ischemic and hemorrhagic stroke patients, accounting for more than 1 in 10 enrolled in a multicenter trial. Hyperacute platinum half-hour patients were largely similar to later-treated patients and are an attainable target for treatment in prehospital stroke trials.

National Institutes of Health Stroke Scale Correlates Well with Initial Intracerebral Hemorrhage Volume.

OBJECTIVES: The US Centers for Medicare and Medicaid Services (CMS) currently publicly reports hospital-quality, risk-adjusted mortality measure for ischemic stroke but not intracerebral hemorrhage (ICH). The NIHSS, which is captured in CMS administrative claims data, is a candidate metric for use in ICH risk adjustment and has been shown to predict clinical outcome with accuracy similar to the ICH Score. Correlation between early NIHSS and initial ICH volume would further support use of the NIHSS for ICH risk adjustment. MATERIALS AND METHODS: Among 372 ICH patients enrolled in a large multicenter trial (FAST-MAG), the relation between early NIHSS and early ICH volume was assessed with correlation and linear trend analysis. RESULTS: Overall, there was strong correlation between NIHSS and ICH volume, r = 0.77 (p < 0.001), and for every 10cc increase in ICH the NIHSS increased by 4.5 points. Correlation coefficients were comparable in all subgroups, but magnitude of NIHSS increase with ICH unit volume increase was greater with left than right hemispheric ICH, with presence rather than absence of IVH, with imaging done within the first hour than second hour after last known well, with men than women, and with younger than older patients. CONCLUSION: Early NIHSS neurologic deficit severity values correlate strongly with initial ICH hematoma volume. As with ischemic stroke, lesion volume increases produce greater NIHSS change in the left than right hemisphere, reflecting greater NIHSS sensitivity to left hemisphere function. These findings provide further support for the use of NIHSS in risk-adjusted mortality measures for intracerebral hemorrhage.

Frequency, Determinants, and Outcomes of Emboli to Distal and New Territories Related to Mechanical Thrombectomy for Acute Ischemic Stroke.

Background and Purpose: Clot fragmentation and distal embolization during endovascular thrombectomy for acute ischemic stroke may produce emboli downstream of the target occlusion or in previously uninvolved territories. Susceptibility-weighted magnetic resonance imaging can identify both emboli to distal territories (EDT) and new territories (ENT) as new susceptibility vessel signs (SVS). Diffusion-weighted imaging (DWI) can identify infarcts in new territories (INT). Methods: We studied consecutive acute ischemic stroke patients undergoing magnetic resonance imaging before and after thrombectomy. Frequency, predictors, and outcomes of EDT and ENT detected on gradient-recalled echo imaging (EDT-SVS and ENT-SVS) and INT detected on DWI (INT-DWI) were analyzed. Results: Among 50 thrombectomy-treated acute ischemic stroke patients meeting study criteria, mean age was 70 (±16) years, 44% were women, and presenting National Institutes of Health Stroke Scale score 15 (interquartile range, 8­19). Overall, 21 of 50 (42%) patients showed periprocedural embolic events, including 10 of 50 (20%) with new EDT-SVS, 10 of 50 (20%) with INT-DWI, and 1 of 50 (2%) with both. No patient showed ENT-SVS. On multivariate analysis, model-selected predictors of EDT-SVS were lower initial diastolic blood pressure (odds ratio, 1.09 [95% CI, 1.02­1.16]), alteplase pretreatment (odds ratio, 5.54 [95% CI, 0.94­32.49]), and atrial fibrillation (odds ratio, 7.38 [95% CI, 1.02­53.32]). Classification tree analysis identified pretreatment target occlusion SVS as an additional predictor. On univariate analysis, INT-DWI was less common with internal carotid artery (5%), intermediate with middle cerebral artery (25%), and highest with vertebrobasilar (57%) target occlusions (P=0.02). EDT-SVS was not associated with imaging/functional outcomes, but INT-DWI was associated with reduced radiological hemorrhagic transformation (0% versus 54%; P<0.01). Conclusions: Among acute ischemic stroke patients treated with thrombectomy, imaging evidence of distal emboli, including EDT-SVS beyond the target occlusion and INT-DWI in novel territories, occur in about 2 in every 5 cases. Predictors of EDT-SVS are pretreatment intravenous fibrinolysis, potentially disrupting thrombus structural integrity; atrial fibrillation, possibly reflecting larger target thrombus burden; lower diastolic blood pressure, suggestive of impaired embolic washout; and pretreatment target occlusion SVS sign, indicating erythrocyte-rich, friable target thrombus.

New Class of Radially Adjustable Stentrievers for Acute Ischemic Stroke: Primary Results of the Multicenter TIGER Trial.

[Figure: see text].

Impact of eloquent motor cortex-tissue reperfusion beyond the traditional thrombolysis in cerebral infarction (TICI) scoring after thrombectomy.

BACKGROUND: Targeted eloquence-based tissue reperfusion within the primary motor cortex may have a differential effect on disability as compared with traditional volume-based (thrombolysis in cerebral infarction, TICI) reperfusion after endovascular thrombectomy (EVT) in the setting of acute ischemic stroke (AIS). METHODS: We explored the impact of eloquent reperfusion (ER) within primary motor cortex (PMC) on clinical outcome (modified Rankin Scale, mRS) in AIS patients undergoing EVT. ER-PMC was defined as presence of flow on final digital subtraction angiography (DSA) within four main cortical branches, supplying the PMC (middle cerebral artery (MCA) - precentral, central, postcentral; anterior cerebral artery (ACA) - medial frontal branch arising from callosomarginal or pericallosal arteries) and graded as absent (0), partial (1), and complete (2). Prospectively collected data from two centers were analyzed. Multivariate analysis was conducted to assess the impact of ER-PMC on 90-day disability (mRS) among patients with anterior circulation occlusion who achieved partial reperfusion (TICI 2a and 2b). RESULTS: Among the 125 patients who met the study criteria, ER-PMC distribution was: absent (0) in 19/125 (15.2%); partial (1) in 52/125 (41.6%), and complete (2) in 54/125 (43.2%). TICI 2b was achieved in 102/125 (81.6%) and ER-PMC was substantially higher in those patients (P<0.001). In multivariate analysis, in addition to age and symptomatic intracranial hemorrhage, ER-PMC had a profound independent impact on 90-day disability (OR 6.10, P=0.001 for ER-PMC 1 vs 0 and OR 9.87, P<0.001 for ER-PMC 2 vs 0), while the extent of total partial reperfusion (TICI 2b vs 2a) was not related to 90-day mRS. CONCLUSIONS: Eloquent PMC-tissue reperfusion is a key determinant of functional outcome, with a greater impact than volume-based (TICI) degree of partial reperfusion alone. PMC-targeted revascularization among patients with partial reperfusion may further diminish post-stroke disability after EVT.

Adiposity and Outcome After Ischemic Stroke: Obesity Paradox for Mortality and Obesity Parabola for Favorable Functional Outcomes.

BACKGROUND AND PURPOSE: A survival advantage among individuals with higher body mass index (BMI) has been observed for diverse acute illnesses, including stroke, and termed the obesity paradox. However, prior ischemic stroke studies have generally tested only for linear rather than nonlinear relations between body mass and outcome, and few studies have investigated poststroke functional outcomes in addition to mortality. METHODS: We analyzed consecutive patients with acute ischemic stroke enrolled in a 60-center acute treatment trial, the NIH FAST-MAG acute stroke trial. Outcomes at 3 months analyzed were (1) death; (2) disability or death (modified Rankin Scale score, 2-6); and (3) low stroke-related quality of life (Stroke Impact Scale

The Effect of Early Treatment with Intravenous Magnesium Sulfate on the Incidence of Cardiac Comorbidities in Hospitalized Stroke Patients.

BACKGROUND: Cardiac adverse events are common among patients presenting with acute stroke and contribute to overall morbidity and mortality. Prophylactic measures for the reduction of cardiac adverse events in hospitalized stroke patients have not been well understood. We sought to investigate the effect of early initiation of high-dose intravenous magnesium sulfate on cardiac adverse events in stroke patients. METHODS: This is a secondary analysis of the prehospital Field Administration of Stroke Therapy-Magnesium (FAST-MAG) randomized phase-3 clinical trial, conducted from 2005-2013. Consecutive patients with suspected acute stroke and a serum magnesium level within 72 hours of enrollment were selected. Twenty grams of magnesium sulfate or placebo was administered in the ambulance starting with a 15-minute loading dose intravenous infusion followed by a 24-hour maintenance infusion in the hospital. RESULTS: Among 1126 patients included in the analysis of this study, 809 (71.8%) patients had ischemic stroke, 277 (24.6%) had hemorrhagic stroke, and 39 (3.5%) with stroke mimics. The mean age was 69.5 (SD13.4) and 42% were female. 565 (50.2%) received magnesium treatment, and 561 (49.8%) received placebo. 254 (22.6%) patients achieved the target, and 872 (77.4%) did not achieve the target, regardless of their treatment group. Among 1126 patients, 159 (14.1%) had at least one CAE. Treatment with magnesium was not associated with fewer cardiac adverse events. A multivariate binary logistic regression for predictors of CAEs showed a positive association of older age and frequency of CAEs (R = 1.04, 95% CI 1.03-1.06, p < 0.0001). Measures of early and 90-day outcomes did not differ significantly between the magnesium and placebo groups among patients who had CAEs. CONCLUSION: Treatment of acute stroke patients with magnesium did not result in a reduction in the number or severity of cardiac serious adverse events.

A Prehospital Acute Stroke Trial has Only Modest Impact on Enrollment in Concurrent, Post-arrival-Recruiting Stroke Trials.

BACKGROUND: Because "time is brain," acute stroke trials are migrating to the prehospital setting. The impact upon enrollment in post-arrival trials of earlier recruitment in a prehospital trial requires delineation. METHODS: We analyzed all patients recruited into acute and prevention stroke trials during an 8-year period when an academic medical center (AMC) was participating in a prehospital treatment trial - the NIH Field Administration of Stroke Treatment - Magnesium (FAST-MAG) study. RESULTS: During the study period, in addition to FAST-MAG, the AMC participated in 33 post-arrival stroke trials: 27 for acute cerebral ischemia, one for intracerebral hemorrhage, and 5 secondary prevention trials. Throughout the study period, the AMC was recruiting for at least 3 concurrent post-arrival acute trials. Among 199 patients enrolled in acute stroke trials, 98 (49%) were in FAST-MAG and 101 (51%) in concurrent, post-arrival acute trials. Among FAST-MAG patients, 67% were not eligible for any concurrent acute, post-arrival trial. Of 134 patients eligible for post-arrival acute trials, 101 (76%) were enrolled in post-arrival trials and 32 (24%) in FAST-MAG. Leading reasons FAST-MAG patients were ineligible for post-arrival acute trials were: NIHSS too low (23.4%), intracranial hemorrhage (17.9%), IV tPA used in standard management (9.0%), NIHSS too high (7.1%), and age too high (5.2%). CONCLUSIONS: A prehospital hyperacute stroke trial with wide entry criteria reduced only modestly, by one-fourth, enrollment into concurrently active, post-arrival stroke trials. Simultaneous performance of prehospital and post-arrival acute and secondary prevention stroke trials in research networks is feasible.