Lower NIHSS Research Articles

Abstract WMP46: Quantitative Electroencephalogram To Assess Neurovascular Coupling Post Endovascular Thrombectomy

Introduction: Persistent neurovascular uncoupling may be associated with poor outcome in patients with ischemic stroke after successful recanalization. Quantitative electroencephalography (EEG) can be used to assess neuronal function. We assessed relation between degree of recanalization post-endovascular thrombectomy (EVT), quantitative EEG based parameters and severity of neurological deficits. Methods: Patients with acute ischemic stroke with large vessel occlusion in anterior circulation were enrolled. EEG was recorded using a modified Muse headband (InteraXon) before, immediately after and at 24 hours post-EVT. Pairwise-derived brain symmetry index (pdBSI) and delta-to-alpha ratio (DAR) were computed using Fitting Oscillation & one-over F (FOOOF) MATLAB wrapper. Results: A total of six patients with mean age 73.6±11.6 years and baseline median (IQR) NIHSS of 13.5 (11-15) were included. Expanded thrombolysis in cerebral infarction (eTICI) scores were 2b67 in one, 2c in two and 3 in three cases. Baseline EEG was recorded at 75 minutes (60-100) from arrival, second at 255 minutes (90-420) after recanalization and third at 28.5 hours (27-31) after recanalization. Four patients with improvement in NIHSS of >10 had 46.6±31.7% change in pdBSI at 24 h. One patient with NIHSS <10 improvement had -25.3% change in pdBSI. One patient with low baseline NIHSS (9) had 90.9% change in pdBSI. There was linear correlation between baseline infarct volume on perfusion studies and change in pdBSI at 24 h (r=0.86, p<0.0001, Figure 1). There was no difference in the DAR in the ipsilateral hemisphere pre-EVT, immediately post-EVT (p=0.6) and 24 h post-EVT (p=0.8). Conclusion: Preliminary data suggest return of neuronal function and clinical recovery may lag after successful recanalization, due to persistent neurovascular uncoupling. Higher baseline infarct volume may predict lower pdBSI change. Portable EEG may help characterise this novel treatment target.

Abstract WP161: Patients With Lower Stroke Scales Take Longer To Treat With Endovascular Thrombectomy Because Of A Longer Time To Identify Their Lvo Not Because Of Longer Procedural Time: Time To Identify And Triage An Lvo Is More Important Determinant Of Treatment Speed Than Procedural Time

Introduction: The seminal trials of thrombectomy in 2015/16 enrolled a relatively homogenous population of patients with ICA terminus or M1 occlusion and a consistent mean NIHSS of 17. However, with advancing techniques and technology, our ability to use EVT for rapid, effective and safe treatment is broadening EVT eligibility to include patients with more distal occlusions, lower NIH Stroke Scales and larger core infarcts. Given the importance of speed in achieving the most favorable outcomes, here we evaluate treatment speed in patients with low NIHSS scores compared to those who have higher NIHSS scores. We also evaluated whether identification of EVT candidacy (door to puncture) or procedural time (puncture to first pass) was a stronger determinant of treatment speed. Methods: Retrospective data from 17 hospitals within the Providence St Joseph Health System were analyzed and included 2,365 acute ischemic stroke patients who received EVT between January 2015 and May 2021. Generalized linear models were used to assess if admission NIHSS impacted the following treatment benchmark times: door to groin puncture (GP) in < 60 minutes, GP to first pass (FP) in <30 minutes or door to FP in < 90 minutes. Patients with an NIHSS of ≥11 were compared to those with an NIHSS of ≤10. Adjusted odds ratios (AOR) and 95% confidence intervals (95% CI) are reported. Results: There were a total of 2,365 EVT patients included, 1,649 (70.0%) with NIHSS ≥ 11 and 707 (30.0%) with NIHSS ≤10. Patients with NIHSS ≥ 11 were more likely to have door to GP < 60 minutes (AOR=1.87, 95% CI: 1.42, 2.47) and door to FP <90 minutes (AOR=1.56, 95% CI: 1.22, 2.00) but not GP to FP <30 min (AOR=.997, 95% CI: .772, 1.29) compared to patients with an NIHSS </=10. Conclusions: Patient’s with lower stroke scales take longer to treat with endovascular thrombectomy. This delay in time to treatment is driven by increased time in identification and triage rather than procedural time.

Posterior Circulation Stroke: Coma (More Than Time) is Brain

Background and purposeContrary to anterior circulation, the legitimacy of endovascular treatment in posterior circulation stroke is still being questioned. Finding reliable prognostic factors and determining how patient selection should be done has become top priority. MethodsObservational and retrospective study from two Portuguese hospitals, including all consecutive patients with posterior circulation occlusions who underwent thrombectomy between January 1st 2015 and December 31st 2019. ResultsOut of a total of 126 patients, the median age was 74 (IQR 61-80) and 39.7% were female. A good clinical outcome (mRS ≤2) was associated with a lower incidence of coma (24,2% vs 66,7%, p < 0,001) and of sudden onset coma (3% vs 18%,=0,04), a lower NIHSS at admission (14 vs 19, p < 0,001), a higher pc-ASPECTS at admission (10 vs 9, p < 0,001) and at 24 h (8 vs 6, p < 0,001) and a higher BATMAN score (7 vs 6, p = 0,017). Differences in the times of symptom-onset-to-recanalization (496 vs 536, p = 0,19) and symptom-onset-to-coma (130 vs 195, p = 0,52) were not remarkable. When excluding NIHSS and pc-ASPECTS at 24 h, coma (p = 0,003; OR=0,22; 95% CI: 0,08-0,59) and the pc-ASPECTS at admission (p = 0,037; OR=1,63; 95% CI: 1,03-2,57) become independent predictors of good outcome. ConclusionsIn strokes from the posterior circulation, coma, more than time, appears to be an important prognostic factor. The BATMAN and the pc-ASPECTS scores were also associated with clinical outcome and coma.

Changes in nerve function and endothelin level in patients with cerebral infarction after treatment with a combination of urinary kallidinogenase and edaravone

&#x0D; &#x0D; &#x0D; &#x0D; Purpose: To investigate changes in neurological function and endothelin (ET) levels in cerebral infarction patients treated with combination of urinary kallidinogenase and edaravone.&#x0D; Methods: Two groups of acute cerebral infarction patients on admission in our hospital from May 2017 to July 2019 were enrolled in this study. The control group (44 patients) received edaravone, while the study group (44 patients) was given urinary kallidinogenase combined with edaravone. Hemorheological indices, NIHSS scores, cerebral edema area, and ET levels, as well as the clinical effects of the treatments were compared. Incidence of major cerebrovascular adverse events during the 26-month follow-up period after treatment was recorded.&#x0D; Results: Compared with the control group, the study group exhibited increase in shear whole blood viscosity, high shear whole blood viscosity and fibrinogen levels after the treatment (p &lt; 0.05); however, lower NIHSS score, ET level and brain edema area were observed in the study group (p &lt; 0.05). Total treatment effectiveness in the study and control groups was 95.45 and 79.55 %, respectively (p &lt; 0.05). Fewer adverse cerebrovascular events were observed in patients in the study group (11.36 vs 29.55 %, p &lt; 0.05). Kaplan-Meier survival curve analysis revealed a mean event-free period of 16.12 months for the study group and 12.41 months for the control group (χ2 = 14.868, p &lt; 0.001).&#x0D; Conclusion: Urinary kallidinogenase combined with edaravone treatment yields a favorable effect in optimizing the hemorheological indices of cerebral infarction patients, reducing the degree of neurological deficits, and elevating ET levels.&#x0D; &#x0D; &#x0D; &#x0D;

Mechanical Thrombectomy in Patients Presenting with NIHSS Score

Background and ObjectivesGroundbreaking trials have shown the tremendous efficacy of mechanical thrombectomy for large vessel occlusions. Currently, mechanical thrombectomy is limited to patients with NIHSS scores ≥6. We investigated the feasibility and safety of MT in patients presenting with NIHSS scores <6. Materials and MethodsA retrospective review of patient who presented with acute ischemic stroke due to large vessel occlusion with an NIHSS score <6 between 2015 – 2021. The patients were then divided into two groups: those who received mechanical thrombectomy and those who did not. ResultsAmong 83 patients, 41 received a mechanical thrombectomy while 42 received medical treatment only. The mean age in the mechanical thrombectomy group was 66 years versus 60 years in the medical group (p = 0.06). Risk factors for stroke did not differ significantly between both groups. 14 patients (34.1%) in the mechanical thrombectomy group and 20 (47.6%) in the medical group received tissue plasminogen activator. No significant difference in clinical improvement (NIHSS) at discharge (p=0.85) or the mRS score at 90 days (p = 0.15) was noted. Mechanical thrombectomy was associated with smaller infarct size (p=0.04) and decreased mortality (p=0.03). ConclusionsMechanical thrombectomy is safe and effective for patients who present with large vessel occlusions and low initial NIHSS scores. Therefore, the decision to offer the patient mechanical thrombectomy or not should not be decided by NIHSS score alone. Rather, the decision should be multifactorial with the aim of maximizing the patients’ outcomes.

Endovascular Treatment Versus Best Medical Management in Acute Basilar Artery Occlusion Strokes: A Propensity-Matched Analysis from the Attention Multicentre Registry

Background: Data regarding the comparative efficacy and safety of endovascular treatment (EVT) versus best medical management (BMM) in strokes due to acute basilar artery occlusion (BAO) remains controversial. Methods: The present analysis was based on the ongoing prospective multicentre endovascular treatment for acute basilar artery occlusion (ATTENTION) registry in China. We performed a propensity score analysis matching patients treated with BMM with those treated with EVT on a 1:3 ratio. Qualifying patients had to present within 24 hours of estimated BAO. The primary clinical outcome was favourable functional outcome (modified Rankin Score 0-3) at 90 days. We also performed a sensitivity analysis within the inversed propensity of treatment weighting (IPTW) cohort. Findings: Our analytic sample comprised 2,134 patients recruited across 48 sites between 2017 and 2021, including 462 patients received BMM and 1,672 patients who received EVT. Age (median, 65), sex (male, 68%), baseline NIHSS score (median, 21), the proportions of favourable imaging profile (PC-ASPECTS ≥8: ~89%), intravenous alteplase use (~23%) and time from onset to admission (median ~ 333 minutes) were comparable across the PSM groups (n=443 in BMM group; n=1,329 in EVT group). Compared with BMM treated patients, there was a significantly higher rate of favourable outcome at 90 days among EVT patients (adjusted relative risk (1.37 [95% CI: 1.18 to 1.60], absolute risk difference 0.11 [95% CI: 0.06 to 0.15]). The mortality was significantly lower (adjusted relative risk (0.81 [95% CI: 0.72 to 0.91], absolute risk difference -0.09 [95% CI: -0.14 to -0.04]) in patients undergoing EVT. Results were generally consistent across the secondary endpoints. Similar associations were seen in the IPTW cohort. Interpretation: In this large, real-world study, EVT was associated with significantly better functional outcomes and survival at 90 days. Well-designed randomized studies comparing EVT with BMM in the acute BAO are needed. Clinical Trial Registration Details: ATTENTION is registered on the Chinese Clinical Trial Registry (http://www.chictr.org.cn; ChiCTR2000041117). Funding Information: ATTENTION was an independent, investigator-initiated registry, and no external support was received. Declaration of Interests: RGN reports consulting fees for advisory roles with Anaconda, Biogen, Cerenovus, Genentech, Hybernia, Imperative Care, Medtronic, Phenox, Philips, Prolong Pharmaceuticals, Stryker Neurovascular, Shanghai Wallaby, Synchron, and stock options for advisory roles with Astrocyte, Brainomix, Cerebrotech, Ceretrieve, Corindus Vascular Robotics, Vesalio, Viz-AI, RapidPulse and Perfuze. RGN is one of the Principal Investigators of the “Endovascular Therapy for Low NIHSS Ischemic Strokes (ENDOLOW)” trial. Funding for this project is provided by Cerenovus. RGN is an investor in Viz-AI, Perfuze, Cerebrotech, Reist/Q’Apel Medical, Truvic, and Viseon. Other authors have no conflict of interest. Ethics Approval Statement: The study was approved by the ethical committee of the first affiliated hospital of university of science and technology of China. All patients or their legally authorized representatives provided signed informed consent.

P.144 Patient-relevant deficit dictates EVT decision-making in low NIHSS patients with medium vessel occlusion stroke

Background: There are no recommendations regarding endovascular treatment (EVT) for patients with acute ischemic stroke (AIS) due to primary medium vessel occlusion (MeVO). The aim of this study was to examine the willingness to perform EVT among stroke physicians in patients with mild, yet personally-disabling deficits due to MeVO. Methods: In an international survey consisting of 4 cases of primary MeVOs, participants were asked whether the presence of personally-disabling deficits would influence their decision-making for EVT despite the patients having low NIHSS scores. Decision rates were calculated based on physician characteristics. Clustered univariable logistic regression was performed. Results: 366 participants from 44 countries provided 2562 answers. 56.9% opted to perform EVT in scenarios in which the deficit was relevant to the patient’s profession versus 41.0% in which no information regarding patient profession was provided (RR1.39, p&lt;0.001). The largest effect sizes were seen for female participants (RR1.68, 95%CI:1.35-2.09), participants &gt;60 years (RR1.61, 95%CI:1.23-2.10), with more neurointervention experience (RR1.60, 95%CI:1.24-2.06), and who personally performed &gt;100 EVTs per year (RR1.63, 95%CI:1.22-2.17). Conclusions: The presence of a patient-relevant deficit in low NIHSS AIS due to MeVO is an important factor for EVT decision-making. This may have relevance for the conduct and interpretation of low NIHSS EVT randomized trials.

Abstract 1122‐000186: Predictors of Functional Outcome in Ischemic Stroke Patients with High Pass Number During Endovascular Therapy

Introduction : The number of thrombectomy passes during endovascular therapy (EVT) for large vessel occlusion (LVO) in acute ischemic stroke (AIS) has been associated with probability of favorable functional outcome, with worse outcomes correlating with greater pass number. While first‐pass recanalization is a strong predictor of functional outcomes, the optimal or maximum recommended number of passes at which patients continue to benefit from EVT remains controversial. Moreover, among patients requiring more attempts, it is unclear if a certain subset of patients continue to benefit despite multiple passes. In this study, we determine predictors of functional outcome among patients requiring a high pass number to achieve successful vessel recanalization. Methods : From our prospectively maintained multi‐institutional registry across 4 comprehensive stroke centers, we identified patients with LVO AIS who underwent EVT requiring ≥ 3 passes to achieve successful reperfusion, defined as ≥ TICI 2b. Patient demographics, co‐morbidities, and severity of stroke based on NIHSS and ASPECTS were included within the analysis. Favorable outcome was defined as 90‐day post‐stroke modified Rankin Scale (mRS) 0–2. The primary outcomes were predictors of favorable outcome, which was assessed by multivariable logistic regression adjusted for age, baseline mRS, NIHSS, admission systolic and diastolic blood pressure, administration of tPA, number of passes during thrombectomy, history of hypertension, hyperlipidemia, atrial fibrillation, coronary artery disease, congestive heart failure, carotid stenosis, and diabetes. Results : Among 116 patients, median age was 70 (IQR 59–80), 48% were female, median NIHSS was 16.5 (IQR 13–22), and median number of passes was 3 (IQR 3–4, range 3–8). Patients with favorable outcome were younger (mean age 63±18.1 vs 70±14.5, favorable vs. non‐favorable, p = 0.041), and had lower NIHSS on presentation (mean 13.9±6.0 vs 18.3±7.4, favorable vs. non‐favorable p = 0.003). Patients with favorable outcome also had lower initial systolic blood pressure (149.6±32.8 vs 163.0±30.0 mmHg, favorable vs. non‐favorable, p = 0.047). In multivariable logistic regression adjusted for demographics and clinical characteristics, lower NIHSS was significantly associated with likelihood of good outcome (OR 0.88, 95% CI 0.81‐0.97, p = 0.009). Conclusions : Patients presenting with lower NIHSS are more likely to benefit from continued EVT attempts. These findings suggest that this population benefits from continued attempts at revascularization.

Clinical features of Trousseau's syndrome with multiple acute ischemic strokes.

Trousseau's syndrome or migrating thrombophlebitis can cause venous or arterial thrombosis; however, multiple acute ischemic strokes (MAIS) caused by Trousseau's syndrome are rare. The aim of this study was to analyse the clinical features of Trousseau's syndrome with MAIS and to improve the awareness and the knowledge of this disease. Clinical data from fifteen patients who were diagnosed as Trousseau's syndrome with MAIS in Rizhao People's Hospital from January 2017 to April 2020 were collected and analysed. The clinical data included the following: patients' basic information (including gender, age, underlying diseases, and tumour stage), laboratory results, imaging features, treatment regimens, and short-term prognoses were collected. The mean age was 65.5years, with thirteen males and two females. Most patients (11/15) had a history of smoking and (or) drinking. The average score of NIHSS was 2.13. 6 of the 15 patients first presented with ischemic stroke and then found the primary tumour. Most common types of primary tumour was lung cancer (11/15), and other types of primary tumour were gastric adenocarcinoma, renal cell carcinoma, oesophageal adenosquamous carcinoma, and cholangiocarcinoma (one in each). All the 15 patients showed different levels of increase of D-dimer. The increase in CRP appears in 10 of the 15 patients. Various tumour markers were increased in the 15 patients, especially for CYFRA-211, all the patients of which were higher than normal. All of the 15 patients had multiple vascular territory lesions in DWI, and most lesions were near the cortex areas. Only 4 of the 15 patients (26.7%) occurred with peripheral venous thrombosis. Thirteen patients were given low molecular heparin for anticoagulant therapy, of which 9 patients were improved in short-term while 4 patients were not. Trousseau's syndrome with MAIS was associated with old-age male, smoking and (or) drinking history, low NIHSS score, increased D-dimer, CRP and tumour markers, and lesions near the cortex areas with multiple vascular territories in DWI. Patients with these features should be alert of malignant tumour. Most common types of primary tumour were lung cancer. Treatment with low molecular heparin may be effective in short term.

Author Response: Thrombectomy vs Medical Management in Low NIHSS Acute Anterior Circulation Stroke

We thank Drs. Khunte and Malhotra for their comments on our study.1 As we have stated in the Discussion section of our article, onset-to-treatment times were not available for our analysis, but we agree that their hypothesis could certainly be true. We are not sure where they saw the increased hemorrhage rate reported in our article because data about intracranial hemorrhages were unverifiable in the Safe Implementation of Treatments in Stroke–Thrombectomy (SITS-TBY) registry and could not be evaluated for our study.1 Furthermore, the MR CLEAN Registry group published a paper recently, which “found no evidence of an association of prior antiplatelet therapy with the risk of symptomatic intracranial hemorrhage after endovascular treatment, nor on functional outcome, reperfusion, or mortality.”2

A Predictive Model for Functional Outcome in Patients with Acute Ischemic Stroke Undergoing Endovascular Thrombectomy

IntroductionEndovascular thrombectomy (EVT) is a well-established treatment of acute ischemic stroke. Variability in outcomes among thrombectomy patients results in a need for patient centered approaches to recovery. Identifying key factors that are associated with outcomes can help prognosticate and direct resources for continued improvement post-treatment. Thus, we developed a comprehensive predictive model of short-term outcomes post-thrombectomy. MethodsThis is a retrospective chart review of adult patients who underwent EVT at our institution over the last four years. Primary outcome was dichotomized 90-day mRS (mRS 0–2 v mRS 3–6). Bivariate analyses were conducted, followed by logistic regression modelling via a backward-elimination approach to identify the best fit predictive model. Results326 thrombectomies were performed; 230 cases were included in the model. In the final predictive model, adjusting for age, gender, race, diabetes, and presenting NIHSS, pre-admission mRS = 0–2 (OR 18.1; 95% 3.44–95.48; p < 0.001) was the strongest predictor of a good outcome at 90-days. Other independent predictors of good outcomes included being a non-smoker (OR 5.4; 95% CI 1.53–19.00; p = 0.01) and having a post-thrombectomy NIHSS<10 (OR 9.7; 95% CI 3.90–24.27; p < 0.001). A decompressive hemicraniectomy (DHC) was predictive of a poor outcome at 90-days (OR 0.07; 95% CI 0.01–0.72; p = 0.03). This model had a Sensitivity of 79%, a Specificity of 89% and an AUC=0.89. ConclusionOur model identified low pre-admission mRS score, low post-thrombectomy NIHSS, non-smoker status and not requiring a DHC as predictors of good functional outcomes at 90-days. Future works include developing a prognostic scoring system.

Modified ICH score was superior to original ICH score for assessment of 30-day mortality and good outcome of non-traumatic intracerebral hemorrhage

IntroductionIntracerebral hemorrhage (ICH) score has been widely used as a consistent and reliable clinical grading scale for predicting mortality. However, ICH score had not been used to predict good outcome or significant disability for those who were alive. We intended to address whether any modifications would increase prediction accuracy for mortality as well as the extent of morbidity for those who survived. MethodsWe conducted a retrospective cohort study, involving all non-traumatic ICH patients admitted to our hospital between September 2018 and July 2020. All non-traumatic ICH patients who were admitted to the stroke unit and registered in our stroke database had their medical records, neuroimaging, and laboratory test results reviewed. Only patients with complete medical records and available CT imaging and laboratory test results were included in our study. Independent predictors of mortality (modified Rankin scale/mRS of 6) or good outcome vs. significant disability (mRS≤2 vs. mRS 3–5, respectively) were identified by logistic regression. A modified ICH (mICH) score was compared with the original ICH (oICH) score for its diagnostic performance (DP). Overall DPs were graded and ranked according to Youden Index (YI). ResultsAs many as 311 patients were eligible with both 39.9% rate of 30-day mortality and good outcome. Factors independently associated with mortality were low GCS and high NIHSS on admission (P = 0.002, <0.001, respectively), and presence of respiratory failure (P < 0.001). Independent factors for good outcome were low NIHSS on admission and mass effect (midline shift > 5 mm) [both P < 0.001]. A modification of ICH score from the original was made by substituting GCS with NIHSS (0 –10 = 1; 11 – 20 = 2; >20 = 3), changing age cut-off point to > 55 years old (= 1), and adding respiratory failure (= 1), and mass effect (= 1). Overall, mICH scored better over oICH score with respect to sensitivity and had comparable specificity for both 30-day mortality and good outcome (sensitivity 80.6% vs. 50.8%; specificity 88.7% vs. 89.3%; YI 0.69 vs. 0.40, respectively) and good outcome (sensitivity 86.3% vs. 77.4%; specificity 74.6% vs. 77.8%; YI of 0.61 vs. 0.55, respectively). There was only one patient with oICH and none on mICH score of 0, who died and none survived with oICH and mICH score of ≥ 5 and ≥ 7, respectively. The proportion of 30-day mortality and good outcome increased in a more linear fashion with mICH score. ConclusionsThe mICH score was proven to be reliable and consistent as a risk grading assessment for non-traumatic ICH patients. The mICH was statistically superior to oICH score in predicting 30-day mortality and good outcome.

Patient-Relevant Deficits Dictate Endovascular Thrombectomy Decision-Making in Patients with Low NIHSS Scores with Medium-Vessel Occlusion Stroke.

There is a paucity of evidence regarding the safety of endovascular treatment for patients with acute ischemic stroke due to primary medium-vessel occlusion. The aim of this study was to examine the willingness among stroke physicians to perform endovascular treatment in patients with mild-yet-disabling deficits due to medium-vessel occlusion. In an international cross-sectional survey consisting of 7 primary medium-vessel occlusion case scenarios, participants were asked whether the presence of personally disabling deficits would influence their decision-making for endovascular treatment despite the patients having low NIHSS scores (<6). Decision rates were calculated on the basis of physician characteristics. Univariable logistic regression clustered by respondent and scenario identity was performed. Three hundred sixty-six participants from 44 countries provided 2562 answers to the 7 medium-vessel occlusion scenarios included in this study. In scenarios in which the deficit was relevant to the patient's profession, 56.9% of respondents opted to perform immediate endovascular treatment compared with 41.0% when no information regarding the patient's profession was provided (risk ratio = 1.39, P < .001). The largest effect sizes were seen for female participants (risk ratio = 1.68; 95% CI, 1.35-2.09), participants older than 60 years of age (risk ratio = 1.61; 95% CI, 1.23-2.10), those with more experience in neurointervention (risk ratio = 1.60; 95% CI, 1.24-2.06), and those who personally performed >100 endovascular treatments per year (risk ratio = 1.63; 95% CI, 1.22-2.17). The presence of a patient-relevant deficit in low-NIHSS acute ischemic stroke due to medium-vessel occlusion is an important factor for endovascular treatment decision-making. This may have relevance for the conduct and interpretation of low-NIHSS endovascular treatment in randomized trials.

Usefulness of combination usage of balloon guide catheter with contact aspiration thrombectomy.

Angiographic outcomes of contact aspiration thrombectomy (CAT), a frontline thrombectomy strategy, can vary depending on balloon guide catheter (BGC) usage, stroke etiology, and occlusion location. The purpose of this study was to analyze conditional outcomes of CAT to determine which result in maximum angiographic benefits. Patients who received CAT for anterior circulation occlusive stroke between January 2017 and December 2018 were included. Angiographic and clinical outcomes were compared relative to BGC use, stroke etiology, and occlusion location. Multivariable analyses for first-pass reperfusion (FPR) and favorable clinical outcome were performed. Of 160 included patients, the rates of FPR, successful reperfusion after CAT, final successful reperfusion, and favorable clinical outcome were 43.1%, 58.1%, 81.9%, and 60.6%, respectively. BGC use was associated with a higher rate of FPR, successful reperfusion after CAT, a lower rate of distal embolization, and faster reperfusion. Based on subgroup analysis, BGC usage in ICA, MCA M1 occlusion, and cardioembolism were associated with higher FPR, successful reperfusion after CAT, and lower distal embolization. Faster reperfusion was achieved in ICA occlusions and cardioembolisms. BGC usage was an independent predictor of FPR. Favorable clinical outcome was associated with male gender, low initial NIHSS score, fast onset to reperfusion, and FPR. In CAT, BGC usage was associated with better angiographic outcomes, including higher FPR, successful reperfusion after CAT, prevention of distal embolization, and faster reperfusion, especially in proximal occlusions and cardioembolisms. These conditions may play a role in maximizing the benefits of CAT.

Abstract 26: Treatment Choice and Discharge Outcomes in Patients Presenting With Large Vessel Occlusion and Low National Institutes of Health Stroke Scale

Introduction: Since 2015, endovascular thrombectomy (EVT) has been widely accepted as the standard of care for patients presenting proximal anterior circulation large vessel occlusion (LVO). However, patient selection for EVT remains uncertain in patients presenting with LVO and low NIHSS. Methods: Retrospective data from 37 hospitals within a large multi-hospital system stroke registry were analyzed and included patients age 18 or over, discharged between January 2016 and May 2020, with an admission NIHSS &lt; 6, and who had a LVO visualized in the internal carotid artery or middle cerebral artery. Patients treated with EVT (with or without IV alteplase), IV alteplase alone, or best medical management (BMM) without IV alteplase or EVT were compared with regard to modified Rankin scale (mRS) at hospital discharge and hospital length of stay (LOS). Pearson’s chi-square square test and Mann-Whitney U test were conducted. Results: Discharge mRS analysis included 742 patients, 211 (28.4%) treated with EVT (with or without IV alteplase), 107 (14.4%) treated with IV alteplase alone, and 424 (57.2%) treated with BMM. A greater proportion of patients treated with IV alteplase alone (71.0%) had no or slight disability (mRS 0-2) compared to EVT (with or without IV alteplase) (51.7%), or BMM (52.6%) (p=.001). Analyses of LOS included 1,037 patients, 298 (28.7%) treated with EVT (with or without IV alteplase), 157 (15.1%) treated with IV alteplase alone, and 582 (56.1%) treated with BMM. Patients treated with IV alteplase alone had significantly shorter LOS (2.0 days, [Interquartile Range:3.0]) compared to EVT (with or without IV alteplase) (3.0 days [4.0]), or BMM (3.0 days [4.0]) (p&lt;.001). Conclusion: Amongst this cohort of patients presenting with anterior circulation LVO and low NIHSS, better discharge outcomes were seen in patients treated with IV alteplase alone, compared to EVT (with or without IV alteplase) or BMM. The best treatment for this patient population remains unclear, and further research is needed.

Abstract P159: Patients Transferred Within a Telestroke Network for Large Vessel Occlusion

Introduction: In a telestroke network, patients at a referring hospital (RH) with large vessel occlusion (LVO) are transferred to a comprehensive stroke center (CSC) for endovascular thrombectomy (EVT). However, a significant number of patients do not ultimately undergo thrombectomy after CSC arrival. Methods: Within a 17 hospital telestroke network, we retrospectively analyzed patients with suspected or confirmed LVO transferred to a CSC and characterized the reasons why these patients did not undergo EVT based on the 2019 AHA guidelines. Results: Of 400 patients transferred to our hub, 68 (17%) were based on vascular imaging at RH. Time from RH arrival to neuroimaging was significantly longer in patients that underwent both CT &amp; CTA brain and neck compared to only CT brain (53 vs. 13 minutes, p &lt;0.05). Accuracy of anterior circulation LVO (ACLVO) detection based on clinical suspicion was 62% (205 of 332 patients). Among 234 ACLVO patients (Table 1), overall 175 (74%) [early window group: 123 (73%) patients and late window group: 52 (80%) patients] met at least one EVT ineligibility criterion. The reasons for EVT ineligibility varied from large core infarct (aspects &lt;6 or core volume &gt;70cc on perfusion imaging in late window), low NIHSS (&lt;6), distal occlusion, and poor baseline mRS (&gt;1) (Table 2). Conclusion: Instituting rapid acquisition and interpretation of vascular imaging at referring hospitals for LVO detection and establishing benchmarks for door to vascular imaging is urgently needed for referring hospitals. Table 1: Study flowchart

Abstract P4: Predictors of Outcomes in Patients With Mild Ischemic Stroke Symptoms: Results From the Mild and Rapidly Improving Stroke Study (mariss)

Background: Although most strokes present with mild symptoms, these have been poorly represented in clinical trials. The objective is to describe multidimensional outcomes, identify predictors of worse outcomes and explore the effect of thrombolysis in this population. Methods: This prospective observational study included patients with ischemic stroke or TIA presenting with stroke symptoms and a baseline NIHSS 0-5 within 4.5 hours from symptom onset. The primary outcome was a 90-day modified Rankin Scale (mRS) 0-1; secondary outcomes included good outcomes in the Barthel Index, Stroke Impact Scale-16 (SIS-16) and European Quality of Life. Multivariable models were created to determine predictors of outcomes and the effect of alteplase. Results: A total of 1765 participants were included from 100 Get With The Guidelines (GWTG)-Stroke participating hospitals (age 65 + 14, 42% women, final diagnosis ischemic stroke 90%, TIA 10%, 57% received alteplase). At 90 days, 37% were disabled and 25% not independent. Worse outcomes were noted for older individuals, women, non-Hispanic Blacks and Hispanics, Medicaid, smokers, those with diabetes, atrial fibrillation, prior stroke, higher baseline NIHSS, visual field defects, arm and leg weakness. Similar outcomes were noted for the alteplase-treated and the untreated groups. Alteplase treated patients were younger (64 + 13 vs. 67 + 1.4) with a higher NIHSS (2.9 + 1.4 vs. 1.7 + 1.4). After adjusting for age, sex, race-ethnicity, and baseline NIHSS, we did not identify an effect of alteplase on the primary outcome but did find an effect on SIS-16 in the restricted sample of baseline NIHSS 3-5. Very few symptomatic hemorrhages were recorded (3/999). Conclusions: A large proportion of stroke patients presenting with a low NIHSS have a disabled outcome. Baseline predictors of worse outcomes are described. An effect of alteplase on outcomes was not identified in the overall cohort but an indication of efficacy was noted in the NIHSS 3-5 subgroup.

Abstract P685: Primary Care Utilization for Primary Prevention Continues to Be Lacking in Patients With Stroke

Introduction: Primary care plays an essential role in stroke prevention. Yet still, for many stroke patients, a relationship with a primary care provider (PCP) is not established until after stroke. Our goal was to determine if lack of PCP and the consequential differences in management affects stroke severity. Methods: Data was obtained from our Institutional Review Board approved stroke admission database from 2017 to November 2019 of all stroke subtypes (ischemic stroke, transient ischemic attack, subarachnoid and intracerebral hemorrhages). Non-parametric Mann Whitney t-test and regression analysis was used to identify significant differences in medications, stroke risk factors and stroke severity. Results: A total of 559 patients were included, median age 67 (interquartile range (IQR) 58-76), 49% woman, 32% established care with a PCP, 36% on medications for diabetes mellitus (DM), 42% hyperlipidemia, 66% anti-hypertensives, 39% anti-platelet agents, and 10% anticoagulation. More patients with PCP were taking anti-hypertensive medications (80% versus (vs) 60%, p value &lt; 0.0001), DM medications (56% vs 30%, p value &lt; 0.0001), anti-platelet agents (46% vs 35%, p value = 0.0149), and medications for hyperlipidemia (49% vs 39%, p value = 0.0426). Admission NIHSS was lower in patients with a PCP median 6 (IQR 3-11) vs median 9 (IQR 4 -15), p value= 0.0016, and median hemoglobin A1c was higher in patients with a PCP 8 (IQR 5.7- 9.3) vs patients without a PCP prior to their stroke 6 (IQR 5.4 - 8.5), p value= 0.0002. Admitting systolic blood pressure was similar 155 (137-177) vs 152 (134-171). After correcting for age and gender, regression analysis demonstrated a significant association between whether a patient had PCP and antihypertensive medication use (odds ratio (OR) 2.413, 95% confidence interval 1.511 - 3.914) and hemoglobin A1c (OR 1.122, 95% CI 1.037 - 1.215). Also, patients with a PCP were more likely to have a lower NIHSS on admission (OR 0.9679, 95% CI 0.9423 - 0.9930). Conclusions: These result show that patients not followed by a PCP prior to stroke are less likely to be on medications for primary prevention of stroke, contributing to an increased stroke severity on admission. More research is needed to identify barriers to patients establishing care with PCP.

Abstract P716: Factors Associated With Functional Dependence at Hospital Discharge in Patients With Low NIHSS Strokes Who Do Not Receive Intravenous Alteplase

Introduction: Patients without prior functional deficits who suffer mild stroke (NIHSS &lt;6) have a 20-30% likelihood of disability (mRS ≥2). Predictors of disability have been described mostly in clinical trials and single center registries. We identified variables associated with functional dependence (mRS ≥3) in mild stroke using a retrospective population-based sample. Methods: Hospitalized strokes from the Greater Cincinnati Northern Kentucky Stroke Study were used. Included patients had an initial NIHSS &lt;6 and baseline mRS 0, both extrapolated from chart review. To minimize the inclusion of patients with disabling symptoms, tPA treatment was excluded. Demographic and clinical characteristics were analyzed by discharge disability status. A multivariable logistic model with least absolute shrinkage and selection operator (lasso) regression analysis identified independent predictors of disability. Results: Of 1268 ischemic strokes, 353 (28%) were functionally dependent at discharge. Increased baseline NIHSS was associated with worse outcome on the mRS. Leg, LOC questions, and sensation NIHSS subscores were the best predictors of outcome. Multivariable analysis identified age, race, hypertension, chronic kidney disease, heart failure, and post-stroke dysphagia as independently associated with discharge mRS ≥3. Discussion: Our results agree with and complement the results of prior studies. They are not limited by inclusion/exclusion criteria or referral bias. Rather, our major limitation is the retrospective estimation of NIHSS and mRS based on physician descriptive documentation rather than direct score assessment. Our results may allow for modeling to better predict outcome which in turn can inform clinical decision making and trial design.

Abstract P407: Etiology And Outcomes Of Non-traumatic Intracerebral Hemorrhage - Data From The Swiss Stroke Registry

Background: We determined the frequency of different etiologies of non-traumatic intracerebral hemorrhage (ICH) and their association with clinical characteristics and outcomes. Methods: We analyzed data from consecutive ICH patients enrolled in the prospective Swiss Stroke Registry (2014-2019). Etiology of ICH was determined according to prespecified, mutually exclusive categories. We assessed prevalence of ICH etiologies, their association with clinical characteristics, functional independence (modified Rankin Scale 0-2), mortality, recurrent ICH and ischemic stroke at 3 months. Results: We included 2584 patients (median age 72y, IQR 64-82, 46.6% female, median NIHSS 10; IQR 3-15). 2037 patients (80%) had hypertension and 553 (22.3%) were on anticoagulants. Distribution of etiologies was as follows: Hypertension (n=1216 patients; 47.1% of all / 56.3% of patients with hypertension), unknown etiology (n=542, 21.0%), antithrombotic therapy (n=225, 8.7% of all / 38% of patients on anticoagulants), cerebral amyloid angiopathy (CAA, n=211, 8.2%), macro-vascular (n=121, 4.7%), other determined etiologies (n=269, 10.4%). Patients with hypertensive ICH had significantly higher NIHSS (median 9; IQR 4-16) and blood pressure levels (median systolic 176; IQR 156-195) on admission. Patients with CAA had significantly lower NIHSS at baseline (median 5; IQR 2-12). Three month follow-up was available for 2109/2584 patients (81.6%). 820 (38.9%) were functionally independent, 658 have died (31.2%). Hypertensive ICH was associated with an increased rate of functional independence (aOR =1.42, 95%CI 1.06-1.90, p=0.02). 5.2% of patients had a cerebrovascular event within 3 months. CAA was associated with a high risk of recurrent ICH (HR 6.95, 95%CI 3.05-15.84, p&lt;0.001). The risk of ischemic stroke (2.2%) was higher than that of ICH (1.5%) in patients with hypertensive ICH. Conclusions: In Swiss Stroke Units and Centers, one of two patients has ICH from a different cause than hypertension. The rate of functionally independent patients at 3 months seems higher than mortality. Absolute and relative risks of recurrent ICH and ischemic stroke after recent ICH differ among underlying etiologies.