Baseline ASPECTS Score Research Articles

Safety and efficacy analysis of endovascular thrombectomy in patients with large vascular occlusion with low Alberta Stroke Program Early Computed Tomography Score

Objective: To evaluate the safety and efficacy of endovascular thrombectomy (EVT) in acute anterior circulation large vessel occlusive stroke (ALVOS) and explore the related influencing factors for prognoses in patients with low Alberta Stroke Program Early Computed Tomography Score (ASPECT). Methods: Patients with acute ALVOS who underwent EVT in Yijishan Hospital of Wannan Medical College from January 2019 to June 2022 were sequentially enrolled. (1) Patients were divided into a low ASPECT group (0-5) and a non-low ASPECT group (6-10), and the differences between the two groups were compared with respect to incidence of perioperative complications and good prognosis rate [modified Rankin scale (mRS) score≤2] 90 days after onset. (2) According to the prognoses 90 days after onset, the low ASPECT group was divided into the good prognosis (mRS score≤2) and poor prognosis (mRS score>2) subgroup. Univariate analysis and multivariate logistic regression analysis were used to investigate the independent risk factors for prognoses of the low ASPECT patients after EVT. Results: A total of 582 patients [age 26-94(69±11) years, 345 male patients (59.3%)] were enrolled for analysis. The baseline ASPECT score was 8 (7, 10), and the baseline NIHSS score was 14 (11, 18). Among them, 102 (17.5%) patients were in the low ASPECT score group and 480 (82.5%) patients were in the non-low ASPECT score group. In the total cohort, patients in the low ASPECT score group had a higher incidence of symptomatic intracranial hemorrhage, lower 90-day good prognosis rate, and higher 90-day mortality rate. Further, propensity score matching statistical analysis showed that patients in the low ASPECT score group had a significantly higher incidence of malignant brain edema after EVT treatment (40.0% vs. 17.6%, χ2=9.13, P=0.003), and a significantly lower 90-day good prognosis rate (24.7% vs. 41.6%, χ2=4.96, P=0.026), but there was no significant difference in the incidence of symptomatic intracranial hemorrhage and 90-day mortality between the two groups (40.3% vs. 26.0%, χ2=3.55, P=0.060). Among 102 patients with low ASPECT score, 22 (21.6%) patients had good prognosis and 80 (78.4%) had poor prognosis. Multivariate logistic regression analysis showed that history of atrial fibrillation (OR=4.478, 95%CI 1.186-16.913, P=0.027) was an independent risk factor for poor prognosis of EVT in patients with low ASPECT score, while good collateral circulation (grade 2 vs. grade 0: OR=0.206, 95%CI 0.051-0.842, P=0.028) was a protective factor for good prognosis of EVT in patients with low ASPECT score. Conclusions: Although the 90-day good prognosis rate of EVT treatment for patients with low ASPECT score was lower than that of the non-low ASPECT group, 21.6% patients still benefitted from EVT treatment, especially patients with non-atrial fibrillation and good collateral circulation. Future studies involving more patients are needed to validate our observations.

Abstract Number: LBA19 Network‐Wide Incidence of Intracranial Hemorrhage in Patients with Acute Ischemic Stroke Receiving Tenecteplase

Introduction Intravenous tenecteplase (TNK) is currently being used as a thrombolytic agent in acute ischemic stroke (AIS) and has has been shown to be non‐inferior to intravenous alteplase according to recent studies. Intracranial hemorrhage (ICH) as a complication of alteplase is approximately at 6%. The aim of our study was to determine the rate of significant ICH in patients receiving TNK indicated for AIS in a real world setting. Methods A network‐wide (3 CSCs, 6 PSCs), multicenter retrospective chart review of patients receiving TNK from February 2020 to January 2022 was performed using the Get With The Guidelines database. TNK bolus dose of 0.25mg/kg was used according to a network‐wide policy. ICH was categorized using ECASS‐3 criteria. Fisher exact test statistic was used to determine if a significant association existed between the presence of ICH and baseline ASPECTS score, endovascular treatment (EVT), and IV eptifibatide use. A benchmark less than 2% PH‐2 incidence was set based on historical alteplase related PH‐2 rates within our network. Social science statistics software was used for data analysis. Results Out of 180 patients who received TNK, 25 subjects (13.89%) developed hemorrhagic transformation. Mean age was 71.88 (95% CI 65.54, 78.22). Forty‐eight percent of subjects were female. Median ASPECTS score was 8 (95% CI 7.54, 8.78). Median 90 day mRS was 3 (95% CI 2.1, 3.9). Hemorrhagic transformation was classified as HI‐1 in 5% (n = 9), HI‐2 in 1.7% (n = 3), PH‐1 in 3.8% (n = 7), and PH‐2 in 3.3% (n = 6) subjects. No significant difference between subjects with other subtypes versus PH‐2 was identified when adjusting for ASPECTS score > = 7 versus < 7 (Fisher value = 1), EVT versus no EVT (Fisher value = 0.65), or use of IV eptifibatide (Fisher value = 0.06). Conclusions Tenecteplase is associated with higher rates of PH‐2 intracranial hemorrhage when compared with our benchmark rates of alteplase‐related PH‐2. This study is significantly limited by small sample size, retrospective nature, and uncontrolled variables. Larger, prospective studies are needed to validate our results.

Abstract Number ‐ 8: HEMERA 1 CarboxyHEMoglobin OxygEn delivery for Revascularization in Acute Stroke: Phase 1 Clinical Trial

Introduction Despitehigh rates ofrecanalizationafter mechanical thrombectomy(MT),only 33–71% of patients achieve functional independence at 90 days.Experimental ischemia hashighlightedthe complexity of several pathophysiological events occurring at the level of the neurovascular unit and has revealed potential targets for neuroprotection. Apossible target is to increasebloodflow in the collateral circulationwhile delivering high levels of oxygen in the ischemic area.Hemoglobin based oxygen carriers (HBOC) as a transfusion media that can treat ischemic tissue have been investigatedfor a decade. More recently, a polyethylene glycol modifiedHBOCin the carboxy state (PP‐007)increases blood flow in the collateral circulationinrat modelsof middle cerebral artery occlusion (MCAO).PP‐007 may deliver more oxygen than Hb contained in RBCs because of increased diffusional surface area in plasma, and by facilitation of oxygen transport from RBC to endothelium.In addition,dilation ofcollateral circulationby diffusion of CO mayslow down infarct expansion andimprove the efficacy of reperfusion. Methods HEMERA 1 is a phase 1 safety clinical trialof PP‐007 in patient with acute ischemic strokewith LVO (ClinicalTrials.gov NCT04677777). Inclusion criteria are patients with Intracranial ICA and/or MCA‐M1 or M2 occlusion,baseline NIHSS ≥ 6, Baseline ASPECTS score ≥ 5 on NCCT and/or Core Volumes <70mL + Mismatch > 50mL on CT perfusion (CTP), time fromlast seen well to start ofPP‐007infusion ≤ 24 hours,pre‐MorbidmRS< 2, and ineligibility for intravenous thrombolysis. The trial plans to enroll approximately 16–20 subjectswith3:1 randomizationtoPP‐007 (320 mg/kg with 30 min bolus + 2‐hour infusion) plus MT versus MT alone. Results Tenpatients have been enrolled so far.Mean age was 76.1 (STD±11.6), ASPECT score = 7.8 (±1.8), NIHSS at baseline = 17.3 (±5.6),TICI 2b or c in 7, TICI 3 in 3. Seven patients were randomized PP‐007 and received the complete infusion. Two patients were randomized to standard of care (MT only) and1was randomized to PP‐007 but not treated.Three patients had elevation of Partial Prothrombin Time (PTT) after the PP‐007 infusion that however had no clinical consequences. Conclusions HEMERA 1 isphase 1 clinical trialcurrently enrolling patients.No safety concerns were identified so far.

Abstract Number ‐ 167: Predictors of Incomplete Recanalization in Mechanical Thrombectomy

Introduction Endovascular mechanical thrombectomy (MT) is a highly effective treatment for acute ischemic stroke (AIS) patients due to large vessel occlusion. Although many of these patients achieve successful recanalization, there remains a proportion of patients who fail to recanalize. Incomplete recanalization (defined as TICI 0–2a) has been associated with poor functional outcome; however, risk factors that may predispose these patients to incomplete recanalization remain unclear. We aimed to evaluate various demographic and procedural variables as predictors of incomplete recanalization. Methods AIS patients from 2019–2022 at our institution were reviewed. All patients who received MT for treatment were identified. Demographic characteristics including comorbidities, medications, thrombolytic use, ASPECTS, hematologic markers as well as procedural data including TICI score, time to clot, technique, occlusion location, and number of passes was assessed. Results One‐hundred eighty‐two patients received MT. Forty‐one patients had incomplete recanalization. History of tobacco use (aOR = 57.8, 95% CI = 5.75—581.2) and no history of HMG‐CoA reductase inhibitor use prior to hospital admission (aOR = 20.9, 95% CI = 1.58—277.1) were found to be predictors of incomplete recanalization. Baseline ASPECTS score, multiple passes with stent retriever, sex, LDL, and hematocrit count were also included in the multivariate analysis due to univariate association (p< 0.10) with the primary outcome. Conclusions A history of tobacco use may indicate a predisposition to difficulty in recanalizing a large‐vessel occlusion with MT. These results may also indicate a protective mechanism of HMG‐CoA reductase inhibitor use in these patients that increases the likelihood of recanalization. While successful recanalization in AIS patients due to large‐vessel occlusion has been well established in recent years to predict improved functional outcome, further investigations evaluating the characteristics of those AIS patients who are unable to be recanalized with MT are warranted.

Abstract TP3: Network-wide Incidence Of Intracranial Hemorrhage In Patients With Acute Ischemic Stroke Receiving Tenecteplase

Background: Intravenous tenecteplase (TNK) is currently being used as a thrombolytic agent in acute ischemic stroke (AIS) and has has been shown to be non-inferior to intravenous alteplase according to recent studies. Intracranial hemorrhage (ICH) as a complication of alteplase is approximately at 6%. The aim of our study was to determine the rate of significant ICH in patients receiving TNK indicated for AIS in a real world setting. Methods: A network-wide (3 CSCs, 6 PSCs), multicenter retrospective chart review of patients receiving TNK from February 2020 to January 2022 was performed using the Get With The Guidelines database. TNK bolus dose of 0.25mg/kg was used according to a network-wide policy. ICH was categorized using ECASS-3 criteria. Fisher exact test statistic was used to determine if a significant association existed between the presence of ICH and baseline ASPECTS score, endovascular treatment (EVT), and IV eptifibatide use. A benchmark less than 2% PH-2 incidence was set based on historical alteplase related PH-2 rates within our network. Social science statistics software was used for data analysis. Results: Out of 180 patients who received TNK, 25 subjects (13.89%) developed hemorrhagic transformation. Mean age was 71.88 (95% CI 65.54, 78.22). Forty-eight percent of subjects were female. Median ASPECTS score was 8 (95% CI 7.54, 8.78). Median 90 day mRS was 3 (95% CI 2.1, 3.9). Hemorrhagic transformation was classified as HI-1 in 5% (n=9), HI-2 in 1.7% (n=3), PH-1 in 3.8% (n=7), and PH-2 in 3.3% (n=6) subjects. No significant difference between subjects with other subtypes versus PH-2 was identified when adjusting for ASPECTS score >=7 versus <7 (Fisher value=1), EVT versus no EVT (Fisher value=0.65), or use of IV eptifibatide (Fisher value=0.06). Conclusion: Tenecteplase is associated with higher rates of PH-2 intracranial hemorrhage when compared with our benchmark rates of alteplase-related PH-2. This study is significantly limited by small sample size, retrospective nature, and uncontrolled variables. Larger, prospective studies are needed to validate our results.

The initial experience with the Embotrap III stent-retriever in a real world setting.

We performed a retrospective review of our prospectively maintained database to identify all patients treated with the Embotrap 3 stent-retriever between January 2021 and January 2022. We recorded the baseline demographics, NIHSS, ASPECT score and clot characteristics, first pass and final eTICI scores, complications and 90 day mRS. One hundred and ten patients met the inclusion criteria, average age 69 ± 14 years, 50% were male (n = 55). The median NIHSS at presentation was 18 (range 3-30) and 58.2% received IV tPA prior to MT. The median ASPECT score on plain CT was 8 with average clot length 20.2 ± 14.8 mm (n = 93). The first pass effect (FPE) was seen in 41.8% of cases with modified FPE seen in 59.1%. A 24-hour CT scan (n = 97) showed median ASPECTs of 7. 43.8% of patients achieve mRS ≤ 2 at 90-day mRS (n = 64). The Embotrap 3 stent-retriever has a high rate of FPE and final recanalization in this real world cohort of patients.

Association of nutritional status with clinical outcomes of stroke patients with acute anterior circulation large vessel occlusion after emergency endovascular treatment

To explore the influence of nutritional status on 90-day functional outcomes of stroke patients with acute large vessel occlusion in the anterior circulation after endovascular treatment (EVT). We retrospectively analyzed the baseline, laboratory, surgical and 90-day follow-up data of patients with stroke resulting from acute large vessel occlusion in the anterior circulation, who underwent emergency endovascular treatment in our hospital from July, 2015 to December, 2020. A favorable outcome was defined as a modified Rankin scale score ≤2 at 90 days. Univariate and multivariate regression analyses were performed to explore the relationship between nutritional status and 90-day functional outcomes of the patients. A total of 459 patients (mean age of 68.29±11.21 years, including 260 males) were enrolled in this study. According to their prognostic nutritional index (PNI), the patients were divided into normal nutrition group (392 cases, 85.4%), moderate malnutrition group (44 cases, 9.6%), and severe malnutrition group (23 cases, 5.0%). Univariate analysis showed that the patients with good clinical outcomes had a lower proportion of malnutrition with a younger age, a lower rate of diabetes, lower baseline blood pressure, lower baseline NIHSS score, higher baseline ASPECT score, and higher rates of good collateral circulation and complete vascular recanalization. Multivariate analysis showed that in addition to age, diabetes, baseline systolic blood pressure, successful recanalization, baseline ASPECT score, baseline NIHSS score and collateral circulation, a greater PNI was a protective factor for a good 90-day outcome of patients after EVT (moderate vs severe: OR=0.245, 95% CI: 0.066-0.908, P=0.035; normal vs severe: OR=0.185, 95% CI: 0.059-0.581, P=0.004). Nutritional status an important factor affecting the 90-day outcomes after EVT of stroke patients with acute large vessel occlusion in the anterior circulation.

Predictors of 90-Day Functional Outcome Following Direct Mechanical Thrombectomy for Anterior Circulation Large Vessel Occlusion: A Prospective Study

Background: Mechanical thrombectomy (MT) is becoming a growing trend in the management of large vessel occlusion (LVO) during the past few decades, although data on the predictors of outcome following MT are scarce. We aimed to study the predictors of 90-day outcome in a cohort of patients with ischemic stroke with large-vessel occlusion. Methods: This was a three-month prospective study of 40 patients with anterior circulation LVO who underwent MT and were followed up for three months with modified Rankin Score (mRS). Results: Of the 40 patients recruited, 55% were men. M1 was the most common vessel occluded (32.5%) followed by internal carotid artery (ICA) and carotid trunk (20%). Tandem occlusion occurred in 25% of the cases. Among the demographic, clinical, radiological, and procedural variables studied, the factors that had a significant impact on the mRS at 3 months were age, diabetes mellitus (DM), hyperlipidemia, stroke mechanism, blood glucose level during procedure, post-procedural National Institutes of Health Stroke Scale (NIHSS), baseline Alberta stroke program early CT score (ASPECT) score, collaterals grade, and procedural thrombolysis in cerebral infarction (TICI) score (P<0.05). On multivariate regression, patients’ age (B: 0.025, 95% CI: 0.001- 0.049, P=0.038), post-procedural NIHSS (B: 0.192, 95% CI: 0.101–0.283, P<0.001), and baseline ASPECT score (B: -0.442, 95% CI: -0.838- -0.046, P=0.03) were the most independent factors to affect the mRS at 3 months. Conclusion: Patients’ age, baseline ASPECT score and post-procedural NIHSS are significant predictors of 90-day outcome of large-vessel occlusion following MT.

Abstract 138: Thrombus Composition Is Associated With First Pass Recanalization

Introduction: Our objective is to identify thrombus composition associated with first pass recanalization (FPR) in mechanical thrombectomy (MT). Methods: Intracranial thrombi obtained in MT were divided in two equal parts. One part was analyzed with anatomopathological studies to quantify fibrin, red-blood cell( Hematoxilin & Eosin) and platelets( cd61 Immunohistochemical staining ) , the other part was analyzed by flow cytometry to quantify leukocyte populations (granulocytes, lymphocytes and monocytes) and their relative proportions . FPR were defined as ≥ mTICI 2b after first pass in MT. Thrombi composition, baseline variables (demographics, previos use of antiplatelets or anticoagulants, blood pressure and blood glucose at hospital arrival ) etiology, intravenous fibrinolysis, ASPECTS score and first attempt thrombectomy devices: direct aspiration, stent retriever or combinations were compared between FPR and Non-FPR groups. Results: Fifty percent (38/76) of the cases analyzed obtained FPR. There were no differences in baseline variables , etiology, Aspects score, previous use of fibrinolysis or type of device used for MT. The thrombi obtained with FPR presented higher proportion of red blood cells (33.64% vs 18.16% p = 0.048) and lymphocytes (10.07% vs 4.43% p = 0.042) and lower proportion of platelets (61, 48% vs 67.26% p = 0.042) in comparison to non-FPR group. The proportion of platelets was an independent marker of FPR (OR 0.97; CI 0.95-0.99). There was an inverse correlation between the proportion of platelets and lymphocytes (rho -0.44, p <0.001). Conclusion: Platelets proportion in intracranial thrombus is an independent marker of first pass recanalization. Inverse relationship between lymphocytes and platelets may be a target for future reperfusion treatments

Abstract 162: Arterial Aspirate Derived Exosomes From Patients With Large Vessel Occlusion Are Associated With Increased Blood-brain Barrier Permeability, Decreased Endothelial Integrity As Well Poor Clinical And Radiographic Outcomes Following Mechanical Thrombectomy

Introduction: Exosomes (~30-150nm microvessicles [MVs]), are important mediators of cell-cell communication and have been associated with injurious and neuroprotective processes in experimental stroke models. Since many patients treated with mechanical thrombectomy (MT) do not improve despite successful recanalization we hypothesized that these exosomes may mediate injurious processes leading to worse outcomes. Methods: As part of an IRB approved protocol we analyzed arterial blood and retrieved clots aspirated during MT from patients with anterior circulation LVO. MVs were isolated and their effects on BBB permeability and endothelial monolayer integrity measured by transepithelial/endothelial electrical resistance (TEER) in cultured human endothelial cells were measured. Following adjustment for age, DM, NIHSS this effect was also correlated (Pearson R) with NIHSS, RAPID™ CTP parameters, TICI score, BP post MT, 24hr ASPECTS, ICH incidence and mRS. Results: Forty-eight patients were enrolled; mean age was 71±14yrs, 56% were female and 20% were African-American. Mean NIHSS was 16±6.6 with a median baseline ASPECTS score of 9 (range 3-10). Baseline CTP parameters (N=21) were: infarct core 25.8±38.5cc, mismatch volume 103±72.2cc and hypoperfusion index (Tmax>10s/Tmax>6s) 0.34±0.25. Recanalization (TICI 2b/c/3) was achieved in 93.8%. The median 24hr ASPECTS was 7 (range 0-10). At last follow-up 43.5% of patients achieved a good outcome (mRS<=2). BBB permeability was associated with NIHSS change (r=-0.31, p=0.0093), TICI (r=-0.31, p=0.031), SBP post MT (r=0.41, p=0.0036) and 24hr ASPECTS (r=-0.31, p=0.015). TEER correlated most strongly with NIHSS change (r=0.36, p=0.0041), TICI (r=0.35, p=0.02), 24hr ASPECTS (r=0.37, p=0.027) and hypoperfusion index (r=-0.4, p=0.041). Conclusions: Arterial aspirate derived MVs can be isolated from LVO stroke patients. Their effects on BBB permeability and endothelial integrity significantly correlated with clinical and radiographical markers of poor outcomes. It is therefore plausible that clot derived exosomes may impact neurological outcomes following MT through endothelial and BBB injury. In addition, these in vitro BBB measures may serve as biomarkers for post-stroke outcomes.

Nomogram to Predict the Number of Thrombectomy Device Passes for Acute Ischemic Stroke with Endovascular Thrombectomy.

PurposeThis study aimed to determine the risk factors associated with the number of thrombectomy device passes and establish a nomogram for predicting the number of device pass attempts in patients with successful endovascular thrombectomy (EVT).MethodsWe enrolled patients from a signal comprehensive stroke center (CSC) who underwent EVT because of large vessel occlusion stroke. Multivariate logistic regression analysis was used to develop the best-fit nomogram for predicting the number of thrombectomy device passes. The discrimination and calibration of the nomogram were estimated using the area under the receiver operating characteristic curve (AUC-ROC) and a calibration plot with a bootstrap of 1000 resamples. A decision curve analysis (DCA) was used to measure the availability and effect of this predictive tool.ResultsIn total, 130 patients (mean age 64.9 ± 11.1 years; 83 males) were included in the final analysis. Age (odds ratio [OR], 1.085; 95% confidence interval [CI], 1.005–1.172; p = 0.036), baseline Alberta Stroke Program Early computed tomography (ASPECTS) score (OR, 0.237; 95% CI, 0.115–0.486; p < 0.001), and homocysteine level (OR, 1.090; 95% CI, 1.028–1.155; p = 0.004) were independent predictors of device pass number and were thus incorporated into the nomogram. The AUC-ROC determined the discrimination ability of the nomogram, which was 0.921 (95% CI, 0.860–0.980), which indicated good predictive power. Moreover, the calibration plot revealed good predictive accuracy of the nomogram. The DCA demonstrated that when the threshold probabilities of the cohort ranged between 5.0% and 98.0%, the use of the nomogram to predict a device pass number > 3 provided greater net benefit than did “treat all” or “treat none” strategies.ConclusionThe nomogram comprised age, baseline ASPECTS score, and homocysteine level, can predict a device pass number >3 in acute ischemic stroke (AIS) patients who are undergoing EVT.

Clot-based radiomics features predict first pass effect in acute ischemic stroke.

Our aim was to evaluate the performance of clot-based radiomics features (RFs) for predicting first pass effect (FPE) in patients with acute ischemic stroke (AIS). The secondary purpose was to search for any other variables associated with FPE. Patients who underwent mechanical thrombectomy (MT) for anterior circulation large vessel stroke in a single center were retrospectively reviewed. Patients were divided into two groups: FPE and non-FPE. Two observers extracted RFs from the clot on pretreatment noncontrast computed tomography (NCCT) images. Demographic, clinical, periprocedural, and RFs were compared between the groups and receiver operating characteristic (ROC) curves were constructed. Logistic regression analysis was used to determine the independent predictors of FPE. Fifty-two patients (27 female, 25 male; mean age 64.50 ± 15.15) who were treated by stent retrievers as the first option were included in the study. FPE was achieved in 25 patients (25/52, 48.1%). Twelve RFs were significantly different between patients with FPE and non-FPE. The long-run low gray-level emphasis (odds ratio = 44.24, p = 0.003) and the zone percentage (odds ratio = 16.88, p = 0.017) were found as independent predictors of FPE. Female sex and a baseline ASPECT score of >8.5 were the other independent variables to predict FPE. The diagnostic accuracy to predict FPE was observed as 83% when using all independent predictors in our predictive model. Clot-based RFs on NCCT may help to estimate the success of the intended outcome of MT in patients with AIS.

Endovascular Treatment Decision Making in Patients with Low Baseline ASPECTS: Insights from UNMASK EVT, an International Multidisciplinary Study

BackgroundCurrent stroke treatment guidelines restrict level 1A recommendations for endovascular therapy to patients with baseline ASPECTS score > 5. However, a recent meta-analysis from the HERMES-group showed treatment benefit in patients with ASPECTS ≤ 5. We aimed to explore how physicians across different specialties and countries approach endovascular treatment decision-making in acute ischemic stroke patients with low baseline ASPECTS. MethodsIn a multidisciplinary survey, 607 stroke physicians were randomly assigned 10 out of a pool of 22 case-scenarios, 3 of which involved patients with low baseline ASPECTS (A:40-year old with ASPECTS 4, B:33-year old with ASPECTS 2 C:72-year old with ASPECTS 3), otherwise fulfilling all EVT-eligibility criteria. Participants were asked how they would treat the patient A) under their current local resources and B) under assumed ideal conditions, without any external (monetary, policy-related or infrastructural) restraints. Overall and scenario-specific decision rates were calculated. Clustered multivariable logistic regression analysis was used to determine the association of baseline ASPECTS with endovascular treatment-decision. ResultsBaseline ASPECTS score was significantly associated with current (OR:1.09, CI 1.05–1.13) and ideal endovascular treatment-decision (OR:1.12, CI 1.08–1.16). Overall current and ideal treatment decision-rates for the low ASPECTS scenarios were 57.1% and 57.6%. Current and ideal rates for the two younger patients were higher (scenario A:69.9/60.4%, scenario B:60.0/61.5%) compared to the 72-year old patient (41.3/40.2%). ConclusionMost physicians decided to proceed with endovascular treatment despite low baseline ASPECTS, particularly in younger patients. This may have implications on the design and execution of low ASPECTS randomized trials.

Risk analysis of post-procedural intracranial hemorrhage based on STAY ALIVE Acute Stroke Registry

Intracranial hemorrhages (ICH) are classified as symptomatic or asymptomatic according to the presence of clinical deterioration. Here, we aimed to find predictive factors of symptomatic intracranial bleeding in a registry-based stroke research. Data of consecutive patients with acute ischemic stroke (AIS) were extracted from the prospective STAY ALIVE stroke registry. Analysis of the total population and treatment sugroups such as endovascular thrombectomy (EVT), intravenous thrombolysis (IVT), or their combination (IVT+EVT) were also done. Outcome measures were ICH, 30- and 90-day clinical outcome based on the modified Rankin Scale (mRS:0-2 as favorable outcome). The hemorrhage was captured by a non-enhanced CT of the skull within 24h after procedure. A total of 355 patients (mean age: 68±11; female N=177 (49.9%); EVT n=131 (36.9%); IVT n=157 (44.2%); IVT+EVT n=67 (18.9%) were included in the analysis. The total number of ICH was47 (13%), symptomatic (sICH) 12 (3.4%) and asymptomatic (aICH) 35 (9.9%) in the whole population. NIHSS ≥15.5 at 24 post stroke hours predicted sICH with a sensitivity of 100% and a specificity of 92% (p<0.001). Furthermore, lower age, good collateral circulation on initial CT angiography and lower NIHSS score measured at 24h independently associated with a favorable 90-day outcome, whereas baseline NIHSS and ASPECT score were not. Although partial recanalization, ASPECT< 6, and poor collaterals were significantly associated with sICH, the only independent predictor was NIHSS ≥15.5 at 24 post stroke hours. This suggests a careful evaluation of patients with worsening NIHSS despite an adequate therapy.

Abstract TP56: Endovascular Treatment Decisions in Acute Ischemic Stroke Patients With Low Baseline Aspects: Insights From an International Multidisciplinary Survey

Background and Purpose: Current AHA/ASA guidelines for the early management of patients with acute ischemic stroke restrict level 1A recommendations for endovascular therapy (EVT) to patients with baseline ASPECTS score &gt;5. However, a recent meta-analysis from the HERMES group showed a treatment benefit in patients with ASPECTS ≤5. We aimed to explore how physicians across different specialties and countries approach endovascular treatment decision-making in acute ischemic stroke patients with low baseline ASPECTS. Methods: In an international multidisciplinary survey, 607 physicians involved in acute stroke care were randomly assigned 10 out of a pool of 22 case-scenarios, 3 of which involved patients with baseline ASPECTS &lt; 6 (A: 40-year old with ASPECTS 4, B: 33-year old with ASPECTS 2 C: 72-year old with ASPECTS 3), otherwise fulfilling all EVT-eligibility criteria. Participants were asked how they would treat the patient in the given scenario A) under their current local resources and B) under assumed ideal conditions, i.e. without any external (monetary, policy-related or infrastructural) restraints. Overall and scenario-specific decision rates were calculated. Clustered multivariable logistic regression analysis was used to determine variables associated with EVT decision in patients with low baseline ASPECTS. Results: 827/6070 responses were available for the low ASPECTS scenarios. Current and ideal treatment EVT decision rates were 57.1% and 57.6% respectively. Current and ideal decision rates were 69.9% and 60.4% for scenario A, 60.0% and 61.5% for scenario B, 41.3% and 40.2% for scenario C respectively. Annual center EVT volume (OR 1.004,p=.004), annual operator EVT volume (OR 1.009, p=.018) and time since symptom onset (OR 4.543,p&lt;.001) were significantly associated with EVT decision-making under current local resources, while annual operator EVT volume (OR 1.007,p&lt;.029) and time since symptom onset (OR 5.687,p&lt;.001) were associated with decision-making under assumed ideal conditions. Conclusion: A majority of physicians decided to proceed with EVT despite low baseline ASPECTS. Operators and centers doing more EVT per year were more likely to offer EVT to patients with low ASPECTS.

Abstract WP502: Predictors Of First Pass Reperfusion In Anterior Circulation Large Vessel Occlusion Stroke

Introduction: The speed and completeness of endovascular reperfusion strongly correlate with functional outcomes. First-Pass Reperfusion (FPR) has been recently established as a critical procedural performance metric for mechanical thrombectomy (MT). We aimed to study the predictors of FPR and its effect on the outcome Methods: Review of a prospectively collected database of MT patients with large vessel occlusion strokes (LVOS) from 05/2012-11/2018. Patients were included in the analysis if they had an anterior circulation LVOS that was successfully reperfused (mTICI 2b-3). FPR was defined as the achievement of mTICI 2c-3 after a single pass with any thrombectomy device. Uni- and multivariate analyses were performed to identify the independent predictors of FPR. Results: A total of 563 patients qualified for the analysis (mean age, 64.4±12.3 years, baseline NIHSS 16.2). FPR was achieved in 202 (35.9%) patients. On univariate analysis, FPR was significantly associated with higher ASPECTS (8.1 vs. 7.8, p=0.008), higher usage of balloon guide catheters (BGC) (88.1% vs. 75.3%, p&lt;0.001), lower use of general anesthesia (9.5% vs. 18.2%, p= 0.006), and shorter procedure duration (mean, 45.5 vs. 79.9 min, p &lt;0.001 and 90.5%). Both BGC (OR, 2.26; 95%CI [1.32-3.87], p=0.003) and ASPECTS (OR, 1.15; 95% CI [1.03-1.28], p= 0.01) were independent predictors of FPE on multivariate regression analysis. Conclusion: Higher baseline ASPECTS score and the use of BGC are strong predictors of First-Pass Reperfusion in mechanical thrombectomy.

Legal authorized representative experience with smartphone-based electronic informed consent in an acute stroke trial

BackgroundThe pilot use of a smartphone platform for electronic informed consent (e-Consent) in large vessel occlusion acute stroke (LVOS) trials has recently been reported. The degree of satisfaction from Legal...

Abstract 160: Outcomes and Relationship to Time: Alteplase Administration in Patients With Large Vessel Occlusion in Non-intervention Group of the Hermes Collaboration

Background: Data on outcomes and time effects of intravenous alteplase on outcome of patients with documented large vessel occlusion (LVO) are scarce. Aim: To define the effect of onset to treatment time (OTT) on functional outcomes and mortality among patients in the non-interventional arm of endovascular stroke trials. Methods: Individual patient-level data from the HERMES collaboration were pooled from seven trials that randomized patients with proven LVO to mechanical thrombectomy + best medical therapy vs. best medical therapy alone. In this analysis only patients who received alteplase directly at the endovascular hospital were included. Primary outcome was degree of disability (mRS distribution) at 3 months. Secondary outcomes included functional independence (mRS 0-2) at 3 months, mortality by 3 months, and symptomatic intracranial hemorrhage (sICH). Results: Among 893 patients in the control arms, 601 received alteplase at the endovascular hospital. The mean age was 66.0 years (SD 13.9), 50% were women, and median NIHSS was 17. 82% were treated within 3 hours from onset and 17% between 3 and 4.5 hours. SICH was observed in 20/585 (3.4%), 3.5% with OTT within 3h vs 3.2% with OTT 3-4.5 hours, p = 1.00. For each 60-minute delay in therapy the cOR for improvement on the mRS was 0.80 (95% CI 0.68 to 0.95, p=0.01) (Figure-A). For each 60-minute delay, the OR for functional independence (mRS 0-2) was 0.82 (95%CI, 0.66 to 1.03, Figure-B). There was no time effect on mortality (cOR, 0.99 (95%CI, 0.79 to 1.23). The reduction in treatment effect by time was not modified by age, baseline NIHSS score, baseline ASPECTS score or occlusion location (p interaction =0.21, 0.81, 0.88, 0.67 respectively). Conclusion: Faster intravenous thrombolysis delivery is associated with better functional recovery in patients with LVO not destined to receive mechanical thrombectomy. Figure legend: A: 90-day functional outcomes stratified by OTT. B: Proportion of mRS 0-2 the 90-day against OTT

Abstract TP317: Hyperglycemia Strongly Predicts Large Ischemic Infarct Growth Despite Full Endovascular Reperfusion

Introduction: Ischemic infarct core grows at variable rates despite early reperfusion. The purpose of this study was to determine the predictors of infarct growth despite full recanalization of a large vessel occlusion in acute ischemic stroke. Method: Patients with acute ischemic stroke due to ICA or MCA occlusion who received endovascular therapy with Thrombolysis in Cerebral Infarction scale (TICI) scores of 2b or greater were subsequently selected between July 2012 and May 2016. The Alberta Stroke Program Early CT Score (ASPECT) was measured on the initial CT or MRI upon arrival and subsequently on the 24-hour scan. The infarct growth (delta d) was measured as initial ASPECT minus 24-hour ASPECT. Large and small infarct growth was defined as delta d of &gt;= to3 and &lt; 3 respectively. The relationship between the infarct growth and baseline variables of blood glucose level(BG), time of symptoms onset to recanalization time and baseline ASPECT score were assessed using statistical analysis. Results: Total of 76 patients were included. 32% had large infarct growth (25/76). The initial ASPECT score was not significantly different between the the 2 subgroups of large and small delta d (7.5 vs 6, P= 0.97). Baseline BG level was significantly higher in the group with larger infarct growth (160 vs 128, P=0.006). The baseline BG level of more than 150 was found as the threshold between the 2 subgroups (P=0.0003). No association was found between the infarct growth and history of diabetes (P= 0.7). Conclusion: Our data suggests that infarct growth occurs in relatively high percentage of ischemic stroke patients despite early full reperfusion of the large vessel occlusion. We showed that baseline blood glucose level particularly levels of higher than 150 is significantly associated with larger infarct growth. Therefore, it can be used as a strong predictive value in early recognition of this patient population.

Abstract W P6: Transfer for Intra-Arterial Stroke Treatment and its Impact on Clinical Outcome

OBJECTIVE: Patients referred to stroke centers from community hospitals for intra-arterial stroke treatment (IAT) may experience significant delay during the transfer process. We sought to determine the difference in clinical outcomes amongst patients presenting directly to stroke centers (PD) versus those transferred from outside community hospitals (TR). METHODS: We reviewed records of patients who underwent IAT at our center from July 2012 – July 2014. All patients had intracranial large vessel occlusion and a baseline ASPECT score of ≥ 6. Patients demographics, risk factors, admission clinical and neuroimaging findings, treatment times and methods, procedure related complications and modified Rankin score (mRS) at 90 days were analyzed. For patients who are not yet at 90 days post-treatment, mRS at hospital discharge was used in the final analysis. A favorable outcome was defined as mRS 2 or less at 90 days. RESULTS: Overall 141 consecutively treated patients were identified. Of these, 89 (63.1%) were transferred from community hospitals for IAT. Median time from last known well to stroke center arrival was 50 mins for PD and 245 mins for TR group (T-test p&lt;0.01). Despite this difference final infarct volume, favorable outcome and mortality rates were comparable between the groups (see table). Multivariate logistic regression model identified lower final DWI infarct volume (OR 0.97, 95%CI 0.95-0.99, p&lt;0.01) and low presentation NIHSS (OR 0.85, 95% CI 0.73-0.99, p=0.04) as predictors of favorable outcome. CONCLUSION: Our results indicate that patients with favorable baseline head CT, referred from outlying facilities, may achieve similar clinical outcomes following IAT when compared to those presenting directly to a designated stroke center. Further randomized studies on an intent to treat design are needed to corroborate these findings.