Occlusion Ischemic Stroke Research Articles

Bihemispheric ischemic strokes in patients with COVID-19.

BACKGROUND:There is emerging evidence that COVID-19 can trigger thrombosis because of a hypercoagulable state, including large-vessel occlusion ischemic strokes. Bihemispheric ischemic stroke is uncommon and is thought to indicate an embolic source. Here, we examine the findings and outcomes of patients with bihemispheric stroke in the setting of COVID-19.METHODS:We performed a retrospective cohort study at a quaternary academic medical center between March 1, 2020, and April 30, 2020. We identified all patients with laboratory-confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection who presented with simultaneous bihemispheric ischemic strokes.RESULTS:Of 637 COVID-19 admissions during the 2-month period, 13 had a diagnosis of acute ischemic stroke, including 5 who developed bihemispheric cerebral infarction. Three of those 5 (60%) were female, median age was 54 (range 41–67), and all five were being managed for severe COVID-19-related pneumonia complicated by acute kidney injury and liver failure before the diagnosis of cerebral infarction was established. Five presented with elevated ferritin, lactate dehydrogenase, and interleukin-6 (IL-6) levels, and four had lymphopenia and elevated D-dimer levels. All patients underwent neuroimaging with computed tomography for persistent depressed mentation, with or without a focal neurologic deficit, demonstrating multifocal ischemic strokes with bihemispheric involvement. Outcome was poor in all patients: two were discharged to a rehabilitation facility with moderate-to-severe disability and three (60%) patients died.CONCLUSIONS:Stroke is implicated in SARS-CoV-2 infection. Although causality cannot be established, we present the imaging and clinical findings of patients with COVID-19 and simultaneous bihemispheric ischemic strokes. Multifocal ischemic strokes with bihemispheric involvement should be considered in COVID-19 patients with severe infection and poor neurologic status and may be associated with poor outcomes.

Research Progress on the Effect of Number of Stent Retriever Passes on the Outcome of Endovascular Treatment of Acute Ischemic Stroke

Introduction: Endovascular treatment is an effective treatment for large vessel occlusive ischemic stroke. The number of Stent Retriever passes is an important link in the strategy of endovascular treatment, and is closely related to the clinical outcome and prognosis of patients with acute ischemic stroke, but there is still a lack of unified understanding. In order to provide reference for clinical practice and related research, this paper reviewed the recent important literatures. Methods: We searched PubMed, Embase, and Cochrane databases, using the terms “stents”, “stroke” and “thrombectomy”. Priority was given to human studies. Only English language papers were accepted. Analyze the articles by title and abstract. Results: The number of Stent Retriever passes is closely related to the rate of recanalization, hemorrhagic transformation, recanalization time, surgical procedures and clinical prognosis. Along with the increase of the number of Stent Retriever passes, the vascular recanculation rate decreased successively, in turn, reduced the rate of blood vessels, 3 times may be the target vascular occlusion which should try the best of times, ≥4 times may not improve the opportunity of recanalization and not conducive to the prognosis, at the same time, increase the risk of HT and related complications occurred. Conclusion: It is necessary to avoid unplanned, additional attempts at EVT. The number of Stent Retriever passes has significant effects on the outcome of EVT of AIS in many aspects. How to better personalized EVT strategy is the focus of future research.

Blood Pressure Trajectory Groups and Outcome After Endovascular Thrombectomy: A Multicenter Study.

Elevated blood pressure after endovascular thrombectomy (EVT) has been associated with an increased risk of hemorrhagic transformation and poor functional outcomes. However, the optimal hemodynamic management after EVT remains unknown, and the blood pressure course in the acute phase of ischemic stroke has not been well characterized. This study aimed to identify patient subgroups with distinct blood pressure trajectories after EVT and study their association with radiographic and functional outcomes. This multicenter retrospective cohort study included consecutive patients with anterior circulation large-vessel occlusion ischemic stroke who underwent EVT. Repeated time-stamped blood pressure data were recorded for the first 72 hours after thrombectomy. Latent variable mixture modeling was used to separate subjects into five groups with distinct postprocedural systolic blood pressure (SBP) trajectories. The primary outcome was functional status, measured on the modified Rankin Scale 90 days after stroke. Secondary outcomes included hemorrhagic transformation, symptomatic intracranial hemorrhage, and death. Two thousand two hundred sixty-eight patients (mean age [±SD] 69±15, mean National Institutes of Health Stroke Scale 15±7) were included in the analysis. Five distinct SBP trajectories were observed: low (18%), moderate (37%), moderate-to-high (20%), high-to-moderate (18%), and high (6%). SBP trajectory group was independently associated with functional outcome at 90 days (P<0.0001) after adjusting for potential confounders. Patients with high and high-to-moderate SBP trajectories had significantly greater odds of an unfavorable outcome (adjusted odds ratio, 3.5 [95% CI, 1.8-6.7], P=0.0003 and adjusted odds ratio, 2.2 [95% CI, 1.5-3.2], P<0.0001, respectively). Subjects in the high-to-moderate group had an increased risk of symptomatic intracranial hemorrhage (adjusted odds ratio, 1.82 [95% CI, 1-3.2]; P=0.04). No significant association was found between trajectory group and hemorrhagic transformation. Patients with acute ischemic stroke demonstrate distinct SBP trajectories during the first 72 hours after EVT that have differing associations with functional outcome. These findings may help identify potential candidates for future blood pressure modulation trials.

Abstract 1122‐000182: Histological Composition of Large Vessel Occlusion Stroke‐Causing Thrombi to Identify Etiologies: Systematic Review and Meta‐Analysis

Introduction : More than a third of large vessel occlusion ischemic strokes do not have clear etiology. Mechanical thrombectomy provides a method to retrieve stroke‐causing thrombi and potentially identifying the etiology. A systematic meta‐analysis is performed to determine if there is a histological difference in red blood cell (RBC) composition of thrombi after the etiology of the stroke is known. Methods : We performed a systematic search through PUBMED and EMBASE. Studies meeting inclusion criteria were identified in which the large vessel occlusion stroke‐causing thrombi histology and etiology of the stroke were determined as either large artery atherosclerotic (LAA), cardioembolic (CE) or cryptogenic. Studies that had the data available or extractable data were selected. Random‐effect models were used to compare the histological difference between each etiology. Results : From inception to August 2021, 4 studies (n = 1022) were used to compare CE vs LAA, 5 studies (n = 1247) were used to compare CE vs cryptogenic and 4 studies (n = 654) were used to compare LAA vs cryptogenic. There was no significant difference in the red blood cells vs white blood cells/fibrin/platelets component between the stroke origins of CE vs LAA (mean difference (MD) ‐1.87; 95% confidence internal [CI]: ‐16.51, 12.78), CE vs cryptogenic (MD 1.18; 95% CI: ‐1.49, 3.86) and LAA vs cryptogenic (MD 7.20; 95% CI: ‐3.93, 18.34). Conclusions : There was no significant gross histological difference between CE, LAA and cryptogenic stroke etiologies and of the large vessel occlusion stroke‐causing thrombi retrieved by mechanical thrombectomy. Further studies into biochemical or genetic markers may be needed to identify stroke etiology.

Abstract 1122‐000234: Hemorrhagic Conversion in Patients Undergoing MT with Concurrent IA tPA with or Without IV tPA/Anticoagulation

Introduction : Introduction There is a growing body of literature on concurrent use of MT and IA tPA use in acute large vessel occlusion ischemic stroke, but few address the risk of IA tPA use in patients also receiving IV tPA or baseline anticoagulation1,23. This cohort study aims to assess the rate of improved functional outcome and complications in patients receiving MT plus IA tPA with or without IV‐tPA or baseline anticoagulation. Methods : In this single institution, retrospective cohort study, medical records of 114 patients undergoing MT who received concurrent IA‐tPA were identified and reviewed. Parameters such as age, sex, admission/discharge mRS scale and NIHSS score, INR, history of anticoagulation use, concomitant IV‐tPA and complications such as any hemorrhage and in hospital death were reviewed. Patients were divided into two groups and two subgroups. First group included patients treated with IA‐tPA who also received IV‐tPA, had an INR above 1.7 or were on anticoagulation therapy. The second group was composed of patients who only received concurrent IA‐tPA. The primary outcomes were hemorrhage, all cause mortality, and good functional outcome (modified Rankin scale equal to or less than 2). The results were calculated and t‐test for two samples analysis was conducted with one‐tail p‐value (&lt;0.05). Results : 74 patients were included in the first group receiving IA‐tPA with either IV‐tPA, or elevated INR or anticoagulated while 40 patients were in the only concurrent IA‐tPA group. 72% versus 60% of the groups respectively have an mRS less or equal to 2 on discharge, p‐value 0.07. 41% of the first group had some type of bleeding on repeat imaging compared to 25% in the IA‐tPA only group, p‐value 0.03. In a subgroup analysis, IV‐tPA alone without prior anticoagulation treatment or an elevated INR, when given in conjunction with IA‐tPA, was an independent risk factor that increased rate of bleeding, 42% versus 25% with a p‐value of 0.04 with an attributable risk of 32%. There was no difference in in‐hospital death rate between the groups. Conclusions : This study shows that in patients receiving MT with concurrent IA tPA with elevated INR&gt;1.7, treatment with anticoagulation at baseline, or concomitant IV‐tPA use increases the risk of hemorrhagic conversion. Therefore, there is a need for careful selection of patients receiving concurrent IA‐tPA. Further investigation is warranted to elucidate which patient groups might maximally benefit from IA‐tPA.

Bihemispheric ischemic strokes in patients with COVID-19

There is emerging evidence that COVID-19 can trigger thrombosis because of a hypercoagulable state, including large vessel occlusion ischemic strokes. Bi-hemispheric ischemic stroke is uncommon and is thought to indicate an embolic source.

Clot Composition Analysis as a Diagnostic Tool to Gain Insight into Ischemic Stroke Etiology: A Systematic Review.

Mechanical thrombectomy renders the occluding clot available for analysis. Insights into thrombus composition could help establish the stroke cause. We aimed to investigate the value of clot composition analysis as a complementary diagnostic tool in determining the etiology of large vessel occlusion (LVO) ischemic strokes (International Prospective Register of Systematic Reviews [PROSPERO] registration # CRD42020199436). Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we ran searches on Medline (using the PubMed interface) and Web of Science for studies reporting analyses of thrombi retrieved from LVO stroke patients subjected to mechanical thrombectomy (January 1, 2006 to September 21, 2020). The PubMed search was updated weekly up to February 22, 2021. Reference lists of included studies and relevant reviews were hand-searched. From 1,714 identified studies, 134 eligible studies (97 cohort studies, 31 case reports, and six case series) were included in the qualitative synthesis. Physical, histopathological, biological, and microbiological analyses provided information about the gross appearance, mechanical properties, structure, and composition of the thrombi. There were non-unanimous associations of thrombus size, structure, and composition (mainly proportions of fibrin and blood formed elements) with the Trial of Org 10172 in Acute Stroke Treatment (TOAST) etiology and underlying pathologies, and similarities between cryptogenic thrombi and those of known TOAST etiology. Individual thrombus analysis contributed to the diagnosis, mainly in atypical cases. Although cohort studies report an abundance of quantitative rates of main thrombus components, a definite clot signature for accurate diagnosis of stroke etiology is still lacking. Nevertheless, the qualitative examination of the embolus remains an invaluable tool for diagnosing individual cases, particularly regarding atypical stroke causes.

Outcomes of Mechanical Thrombectomy in the Early (

Current stroke care recommendations for patient selection for mechanical thrombectomy in the extended time window demand advanced imaging to determine the stroke core volume and hypoperfusion mismatch, which may not be available at every center. We aimed to determine outcomes in patients selected for mechanical thrombectomy solely on the basis of noncontrast CT and CTA in the early (<6-hour) and extended (≥6-hour) time windows. Consecutive mechanical thrombectomies performed for acute large-vessel occlusion ischemic (ICA, M1, M2) stroke between February 2016 and August 2020 were retrospectively reviewed. Eligibility was based solely on demographics and noncontrast CT (ASPECTS) and CTA, due to the limited availability of perfusion imaging during the study period. Propensity score matching was performed to compare outcomes between time windows. Of 417 mechanical thrombectomies performed, 337 met the inclusion criteria, resulting in 205 (60.8%) and 132 (39.2%) patients in the 0- to 6- and 6- to 24-hour time windows, respectively. The ASPECTS was higher in the early time window (9; interquartile range = 8-10) than the extended time window (9; interquartile range = 7-10; P = .005). Propensity score matching yielded 112 well-matched pairs. Equal rates of TICI 2b/3 revascularization and symptomatic intracranial hemorrhage were observed. A favorable functional outcome (mRS 0-2) at 90 days was numerically more frequent in the early window (45.5% versus 33.9%, P = .091). Mortality was numerically more frequent in the early window (25.9% versus 17.0%, P = .096). Patients selected for mechanical thrombectomy in the extended time window solely on the basis of noncontrast CT and CTA still achieved decent rates of favorable 90-day functional outcomes, not statistically different from patients in the early time window.

NIHSS 24 h After Mechanical Thrombectomy Predicts 90-Day Functional Outcome.

Mechanical thrombectomy (MT) for large vessel occlusion (LVO) ischemic stroke is asafe and effective treatment modality. The National Institute of Health Stroke Scale (NIHSS) 24 h after MT (24 h-NIHSS) was shown to serve as the strongest surrogate for 90-day functional outcome. Here, we seek to externally validate 24 h-NIHSS as predictor for 90-day functional outcome and explore additional variables in this context. Patients treated for anterior LVO between February 2016 and August 2020 with premorbid mRS < 3 were included. Receiver operating characteristics were used to compare different NIHSS-related surrogates, such as baseline (B) NIHSS, 24 h-NIHSS, Δ‑NIHSS and percent (%) change NIHSS to predict favorable function outcome (mRS 0-2). Additional analysis was performed to assess predictors associated with poor outcome despite reaching the best predictor threshold. Atotal of 337 eligible cases were identified. The 24 h-NIHSS outperformed B‑NIHSS, Δ‑NIHSS, and %‑NIHSS in terms of 90-day mRS 0-2 prediction. A 24-NIHSS ≤ 8 was identified as the optimal binary threshold. Multivariable analysis demonstrated that 24-NIHSS ≤ 8 and younger patient age were independently associated with mRS 0-2. Despite achieving 24 h-NIHSS ≤ 8, 23/143 (16.1%) cases experienced poor outcome (mRS 4-6). Older age, higher baseline NIHSS, coexisting chronic kidney disease, and longer hospital stay were independent predictors for poor outcome despite achieving 24 h-NIHSS ≤ 8. An NIHSS of 8 or less 24 h after MT was validated to serve as an independent, strong surrogate for favorable functional outcome; however, cofactors such as older age, higher baseline NIHSS and coexisting comorbidities appear to mitigate this clinical adjunct.

Investigating the “Weekend Effect” on Outcomes of Patients Undergoing Endovascular Mechanical Thrombectomy for Ischemic Stroke

Objectives: With growing evidence of its efficacy for patients with large-vessel occlusion (LVO) ischemic stroke, the use of endovascular thrombectomy (EVT) has increased. The “weekend effect,” whereby patients presenting during weekends/off hours have worse clinical outcomes than those presenting during normal working hours, is a critical area of study in acute ischemic stroke (AIS). Our objective was to evaluate whether a “weekend effect” exists in patients undergoing EVT. MethodsThis retrospective, cross-sectional analysis of the 2016–2018 Nationwide Inpatient Sample data included patients ≥18 years with documented diagnosis of ischemic stroke (ICD-10 codes I63, I64, and H34.1), procedural code for EVT, and National Institutes of Health Stroke Scale (NIHSS) score; the exposure variable was weekend vs. weekday treatment. The primary outcome was in-hospital death; secondary outcomes were favorable discharge, extended hospital stay (LOS), and cost. Logistic regression models were constructed to determine predictors for outcomes. ResultsWe identified 6052 AIS patients who received EVT (mean age 68.7±14.8 years; 50.8% female; 70.8% White; median (IQR) admission NIHSS 16 (10-21). The primary outcome of in-hospital death occurred in 560 (11.1%); the secondary outcome of favorable discharge occurred in 1039 (20.6%). The mean LOS was 7.8±8.6 days. There were no significant differences in the outcomes or cost based on admission timing. In the mixed-effects models, we found no effect of weekend vs. weekday admission on in-hospital death, favorable discharge, or extended LOS. ConclusionThese results demonstrate that the “weekend effect” does not impact outcomes or cost for patients who undergo EVT for LVO.

A Novel Combination of Blood Biomarkers and Clinical Stroke Scales Facilitates Detection of Large Vessel Occlusion Ischemic Strokes.

Acute ischemic stroke caused by large vessel occlusions (LVOs) is a major contributor to stroke deaths and disabilities; however, identification for emergency treatment is challenging. We recruited two separate cohorts of suspected stroke patients and screened a panel of blood-derived protein biomarkers for LVO detection. Diagnostic performance was estimated by using blood biomarkers in combination with NIHSS-derived stroke severity scales. Multivariable analysis demonstrated that D-dimer (OR 16, 95% CI 5–60; p-value < 0.001) and GFAP (OR 0.002, 95% CI 0–0.68; p-value < 0.05) comprised the optimal panel for LVO detection. Combinations of D-dimer and GFAP with a number of stroke severity scales increased the number of true positives, while reducing false positives due to hemorrhage, as compared to stroke scales alone (p-value < 0.001). A combination of the biomarkers with FAST-ED resulted in the highest accuracy at 95% (95% CI: 87–99%), with sensitivity of 91% (95% CI: 72–99%), and specificity of 96% (95% CI: 90–99%). Diagnostic accuracy was confirmed in an independent cohort, in which accuracy was again shown to be 95% (95% CI: 87–99%), with a sensitivity of 82% (95% CI: 57–96%), and specificity of 98% (95% CI: 92–100%). Accordingly, the combination of D-dimer and GFAP with stroke scales may provide a simple and highly accurate tool for identifying LVO patients, with a potential impact on time to treatment.

Interobserver Agreement in Scoring Angiographic Results of Basilar Artery Occlusion Stroke Therapy.

The modified TICI Infarction grading system is a metric currently used to evaluate angiographic results of thrombectomy for large-vessel occlusion in ischemic stroke. Originally designed for evaluating MCA territories, it is currently used for other vessel occlusions, including the posterior circulation. We postulate that the modified TICI use for the posterior circulation is not accurate due to the different vascular territories supplied by vertebrobasilar vasculature, making grading more complex. We collected angiographic results from 30 patients who presented with acute posterior circulation occlusions between 2015 and 2018 and underwent thrombectomy in our institution. Eight observers were asked to evaluate the TICI scores before and after thrombectomy. The multirater statistics were computed using Fleiss κ analysis. Further data were collected regarding the potential brain territories at risk and the existence of atherosclerotic disease in the basilar artery. The overall agreement κ reached 0.277 (SD, 0.013), which suggests a "fair" agreement among the raters. On average, 45% of observers achieved a high accuracy in predicting brain areas at risk of ischemia. As for the existence of basilar atherosclerotic disease, a high agreement (defined as at least 5 of 6 observers) was seen in 20 of the 30 patients. Despite TICI being ubiquitous in stroke diagnostics, the high variability of posterior circulation TICI scores calls into question its use in these strokes. Other methods should be developed to assess recanalization in the posterior circulation.

Sex-specific differences in presentations and determinants of outcomes after endovascular thrombectomy for large vessel occlusion stroke.

Sex-specific differences in ischemic stroke outcomes are prevalent. We sought to investigate sex differences in the determinants of reperfusion and functional outcomes after endovascular thrombectomy (EVT) for emergent large vessel occlusion ischemic stroke (ELVO). Patients presenting to a single referral center with an anterior circulation ELVO that underwent EVT from 2011 to 2019 were included in this retrospective analysis. Sex differences in history, presentation, adequate reperfusion (TICI 2b-3), and 90-day good outcome [delta modified Rankin Scale (mRS) ≤ 2 from pre-stroke] were examined. Multivariable logistic regression analyses were performed to assess sex-specific associations with outcomes. Three hundred and eighty-one consecutive ELVO patients were identified. Women (N = 193) were older (75 vs 64years, p < 0.0001), had more pre-stroke disability (17% vs 9%, p = 0.032), more atrial fibrillation (41% vs 30%, p = 0.033), but less carotid atherosclerosis (8% vs 16%, p = 0.027). Rates of TICI 2b-3 and good outcome were similar between sexes. Carotid atherosclerosis (OR 0.315, 95% CI 0.130, 0.762) and dissection (OR 0.124, 95% CI 0.027, 0.569) independently decreased the odds of TICI 2b-3 among men but not women. Older age, more severe stroke, and not achieving TICI 2b-3 independently decreased the odds of good outcome among both sexes, while prior stroke (OR 0.258, 95% CI 0.083, 0.797) and hemorrhagic transformation (OR 0.111, 0.021, 0.592) were determinants exclusive to men. In a real-world analysis of ELVO stroke patients treated with EVT, we found that despite advanced age and more pre-stroke disability, women have comparable reperfusion rates and functional outcomes compared to men. Sex-specific determinants of reperfusion and functional outcome were identified that require further study.

Stent-retriever alone vs. aspiration and stent-retriever combination in large vessel occlusion stroke: A matched analysis.

Three randomized clinical trials have reported similar safety and efficacy for contact aspiration and stent-retriever thrombectomy. We aimed to determine whether the combined technique (stent-retriever + contact aspiration) was superior to stent-retriever alone as first-line thrombectomy strategy in a patient cohort where balloon guide catheter was universally used. A prospectively maintained mechanical thrombectomy database from January 2018 to December 2019 was reviewed. Patients were included if they had anterior circulation proximal occlusion ischemic stroke (intracranial ICA or MCA-M1/M2 segments) and underwent stent-retriever alone thrombectomy or stent-retriever + contact aspiration as first-line therapy. The primary outcome was the first-pass effect (mTICI2c-3). Secondary outcomes included modified first-pass effect (mTICI2b-3), successful reperfusion (mTICI2b-3) prior to and after any rescue strategy, and 90-day functional independence (mRS ≤ 2). Safety outcomes included rate of parenchymal hematoma type-2 and 90-day mortality. Sensitivity analyses were performed after dividing the overall cohort according to first-line modality into two matched groups. A total of 420 patients were included in the analysis (mean age 64.4 years; median baseline NIHSS 16 (11-21)). As compared to first-line stent-retriever alone, first-line stent-retriever + contact aspiration resulted in similar rates of first-pass effect (53% vs. 51%, adjusted odds ratio (aOR) 1.122, 95%CI (0.745-1.691), p = 0.58), modified first-pass effect (63% vs. 60.4%, aOR1.250, 95%CI (0.782-2.00), p = 0.35), final successful reperfusion (97.6% vs. 98%, p = 0.75), and higher chances of successful reperfusion prior to any rescue strategy (81.8% vs. 72.5%, aOR 2.033, 95%CI (1.209-3.419), p = 0.007). Functional outcome and safety measures were comparable between both groups. Likewise, the matched analysis (148 patient-pairs) demonstrated comparable results for all clinical and angiographic outcomes except for significantly higher rates of successful reperfusion prior to any rescue strategies with the first-line stent-retriever + contact aspiration treatment (81.8% vs. 73.6%, aOR 1.881, 95%CI (1.039-3.405), p = 0.037). Our findings reinforce the findings of ASTER-2 trial in that the first-line thrombectomy with a combined technique did not result in increased rates of first-pass reperfusion or better clinical outcomes. However, the addition of contact aspiration after initial stent-retriever failure might be beneficial in achieving earlier reperfusion.

Which Acute Ischemic Stroke Patients Are Fast Progressors?: Results From the ESCAPE Trial Control Arm.

Fast infarct progression in acute ischemic stroke has a severe impact on patient prognosis and benefit of endovascular thrombectomy. In this post hoc analysis of the ESCAPE trial (Endovascular Treatment for Small Core and Proximal Occlusion Ischemic Stroke), we identified acute ischemic stroke patients with rapid infarct growth and investigated their baseline clinical and imaging characteristics. Control arm patients were included if they had follow-up imaging at 2-8 hours without substantial recanalization, and if their baseline Alberta Stroke Program Early CT Score was ≥9. Fast infarct progression was defined as Alberta Stroke Program Early CT Score decay ≥3 points from baseline to 2- to 8-hour follow-up imaging. Clinical and imaging baseline characteristics were compared between fast progressors and other patients, and occlusion site and collateral flow patterns were assessed in detail. Fast infarct progression occurred in 15 of 43 included patients (34.9%). Fast progressors had worse collaterals (poor in 3/15 [20%] versus 0/28 patients, P=0.021) and more carotid-T or -L occlusions (8/15 [53.4%] versus 3/28[10.7%], P=0.021). In 8 out of 15 (53.3%), occlusion site and circle of Willis configuration prevented collateral flow via the anterior or posterior cerebral artery. Most patients with fast infarct progression had terminal carotid occlusions and impaired collateral flow via the anterior or posterior cerebral artery, indicating that occlusion location and intracranial vascular anatomy are relevant for infarct progression.

Blood Pressure Reductions in the Hyperacute Phase of Large Vessel Occlusion Ischemic Stroke Are Associated With Infarct Progression And Poor Functional Outcome (5141)

Blood Pressure Reductions in the Hyperacute Phase of Large Vessel Occlusion Ischemic Stroke Are Associated With Infarct Progression And Poor Functional Outcome (5141)

Severe Neurologic Complications of SARS-CoV-2.

Purpose of ReviewThis review presents an overview of the known neurocritical care complications of severe acute respiratory virus 2 (SARS-CoV-2). We present readers with a review of the literature of severe neurologic complications of SARS-CoV-2 and cases from our institution to illustrate these conditions.Recent FindingsNeurologic manifestations are being increasingly recognized in the literature. Some patients can have severe neurologic manifestations, though the true prevalence is unknown.SummarySevere neurologic complications of COVID-19 include large vessel occlusion ischemic stroke, intracranial hemorrhage, encephalitis, myelitis, Guillain-Barre syndrome, status epilepticus, posterior reversible encephalopathy syndrome, and hypoxic-ischemic encephalopathy. These conditions can manifest in COVID-19 patients even in the absence of risk factors and must be promptly identified as they can have a high mortality if left untreated.

Abstract P262: Early Withdrawal of Life Sustaining Treatment After Mechanical Thrombectomy: A Quantitative and Qualitative Analysis

Background: Mechanical thrombectomy (MT) is now standard of care for patients with acute large vessel occlusion (LVO) ischemic stroke, after several trials showed significant functional improvement at 90 days. Despite this expected duration for recovery, withdrawal of life sustaining treatment (WLST) often occurs within less than 5 days after MT. We aimed to identify determinants of early WLST and better understand decisions that led to it. Methods: Retrospective chart review at a single academic stroke center from 1/2015 to 8/2020 using mixed methods. We compared patient characteristics and hospital course in those with early WLST (within 5 days) to those without WLST. Six authors conducted in-depth qualitative analysis of family meeting notes among a subgroup of 16 purposively sampled early WLST patients. Results: Among 402 patients (mean age 68.0, SD 14.7 years; 53.7% male) who underwent MT, 88 (21.9%) had WLST, of which 52 (12.9%) were early WLST (mean 2.2, SD 1.3 days). Logistic regression adjusted for sex, race, LVO location, time of MT from last known normal, and post-procedural hemorrhage showed early WLST compared to no WLST was significantly associated with older age, inpatient stroke, increased stroke severity, unsuccessful MT, no tPA given, post-procedural need for craniectomy, and palliative care consultation (p&lt;0.05). One key theme that emerged from goals-of-care conversations was clarity among families of patient’s wishes, with a low tolerance for dependence, which led to early WLST if independence was unlikely immediately after MT. Conclusion: Early WLST after MT occurs frequently in patients with severe stroke and high medical complexity, especially if progression to cerebral herniation. Clear communication before and after MT regarding expected prognosis and trajectory of recovery could allow for improved decision making and prevent potentially premature WLST by providers or families. Prior knowledge of patient’s goals-of-care may also reduce patient or caregiver suffering and improve resource utilization for the healthcare system in patients with severe stroke.

Abstract MP36: Blood Pressure Reductions in the Hyperacute Phase of Large Vessel Occlusion Ischemic Stroke Are Associated With Infarct Progression and Poor Functional Outcome

Introduction: Decreases in blood pressure (BP) during endovascular therapy (EVT) have been associated with infarct progression and worse outcome after large vessel occlusion (LVO) stroke. However, BP trajectories in the hyperacute phase prior to EVT have not been well characterized. We used high-frequency BP and hemodynamic monitoring to study the timing of BP reductions during the hyperacute period of stroke and evaluated their relation to infarct progression and functional outcome. Methods: We prospectively enrolled patients with anterior circulation LVO stroke undergoing EVT. BP and cardiac hemodynamic variables were recorded every 20 seconds from ER admission until the end of EVT using non-invasive finger plethysmography. Patients underwent initial CT perfusion imaging and a follow-up MRI at 24 hours to calculate infarct growth. The following hemodynamic parameters were defined as exposure variables: the difference between admission MAP and lowest MAP (ΔMAP), MAP drop&gt; 20% from admission, MAP&lt;70 mmHg, and SBP&lt;140 mmHg. Functional outcome was measured with the modified Rankin Scale (mRS) at 90 days. Core associations between BP reductions and outcomes were studied using linear regression and logistic regression models. Results: 45 patients underwent continuous BP monitoring (age 72±17; 58% female; NIHSS 13±6). Aggregated time series data revealed a marked BP reduction around the time of imaging from which patients recovered (mean SBP 33 mmHg, duration 18 min). A sustained decrease in BP was observed after groin puncture without return to baseline BP levels. A linear regression analysis revealed a 13ml infarct growth for every 10 mmHg reduction in ΔMAP (p=0.054). Patients were divided into two groups based on median ΔMAP = 29. Those with ΔMAP ≤29 had better functional outcome at 90 days (34.78% vs. 9.09%, p = 0.038). Conclusion: Marked and frequently iatrogenic BP reductions occur around the time of initial imaging and may present a potential target for therapeutic intervention. Decrease in blood pressure before reperfusion may increase the risk of infarct progression and poor functional outcome. Changes in cardiac hemodynamic variables throughout the acute stroke period suggest a potential role for fluid resuscitation for hemodynamic optimization.

Abstract P483: Immediate Feedback to Emergency Medical Services Reduce Door to Angiogram and Transfer Time for Endovascular Treatment of Large Vessel Occlusion Ischemic Strokes

Background: The morbidity of acute ischemic Stroke (AIS) caused by a large vessel occlusion (LVO) can be significantly reduced with endovascular intervention. However, delay in diagnosis can exclude a patient from therapy.Rapid Arterial Occlusion evaluation (RACE) score of five or more have an 85% chance of being LVO acute ischemic stroke. Pre-arrival notification of potential LVO cases by EMS (Emergency Medical Service) is an important factor to reduce door-to-transfer time from a Primary Stroke Center (PSC) to a Comprehensive Stroke center (CSC). We hypothesize that immediate feedback to EMS teams on their pre-hospital RACE score reporting will improve prehospital recognition of LVO strokes. Therefore, reducing the Door to Needle CTA (CT Angiogram) and/or Door to Transfer Time for endovascular treatment. Methods: Our inclusion criteria included patients with a diagnosis of AIS brought in by EMS with a RACE score of five or more, was given IV thrombolytics, or transferred to a comprehensive stroke center for endovascular treatment. A 5-item feedback form was developed for each case and was reviewed biweekly with our EMS liaison. Feedback included compliance with RACE score reporting, presence of IV access, CTA time, and TPA/Transfer time. Direct feedback was verbally given to the EMS transport team. Results: Comparison of data from a twelve-month preintervention period (n=29) to a four-month postintervention period (n=12) was conducted through direct comparison. This showed a decrease in mean Door-to-CTA time from 212.14 (CI ±83.3) to 97.08 (CI ±54.92) minutes with a p-value of 0.0126 in a one-tailed t-Test, a 54% reduction and a reduction in door to transfer time (305 minutes to 132 minutes, a 56.7 % reduction ). Conclusion: A pilot project focused on providing immediate feedback to EMS regarding accurate prehospital notification of RACE score showed a statistically significant improvement in door to CTA time and door to transfer time. Extension of the post study period is needed to confirm the significance of transfer time. This study demonstrates the importance of collaboration between a PSC and EMS to ensure prompt diagnosis and transfer for endovascular treatment of AIS caused by LVO.