Treatment Of Acute Ischemic Stroke Research Articles

Abstract TP212: 2b or Not 2b? TICI 2b Reperfusion Score in Endovascular Thrombectomy for Acute Ischemic Stroke Carries a Poor Functional Outcome

Background: Endovascular thrombectomy (EVT) for treatment of acute ischemic stroke (AIS) in the proximal cerebrovasculature has, since its inception, become part of the standard of care when addressing AIS. Overall, one in six individuals treated has improved neurologic and functional outcomes. Reperfusion following thrombectomy in the anterior cerebral circulation has long been graded by the modified Thrombolysis in Cerebral Infarction (mTICI) scale-and the score of mTICI (2b, or, “partial filling of more than 50% of the affected vascular territory” is considered the benchmark for “good” outcomes in EVT. It remains unclear whether this score at time of reperfusion reliably predicts a sustained improvement in neurologic or functional outcome. Method: This is a retrospective review of all anterior AIS patients with large vessel occlusion (LVO) at Barrow Neurological Institute between 01/01/2018 and 12/31/2022 who underwent EVT with mTICI 2b or greater. The study was approved by the local IRB. Demographic data of patients between the ages of 18 and 95 who had AIS with LVO in the anterior Circle of Willis or its supplying vessels were collected. Other variables collected and analyzed include mTICI score, and modified Rankin Score (mRS) at discharge and 90 days. The TICI grade was obtained via digital cerebral angiography post EVT. Descriptive statistics was used to examine the differences of mRS scores at 90 days. Results: Of 81 cases reviewed, 52 (65%) had a TICI 2b score and their average mRS was 3.7, 20 (25%) had a TICI 2c and their average mRS was 3.6, and 4 (5%) had a TICI 3 with mRS 3 at discharge. At 90 days, the average mRS for TICI 2b patients was 3.2, for TICI 2c patients 2.9 and for TICI 3 patients 2.3. No difference in the rate of intracerebral hemorrhage (ICH) following reperfusion between the TICI 2 and 3 groups (17%). Conclusion: Our results demonstrated that patients with a mTICI of 2b had a higher mean mRS at discharge and minimal improvement of mRS at 90 days compared against patients with a mTICI of 2c or 3 (average change in score was -0.6, -0.7 and -1.3 in the TICI 2b, 2c and 3 groups respectively). Therefore, a reperfusion score of mTICI 2b may not be sufficient to indicate a high probability of a good functional outcome. With EVT, reaching a TICI 3 should be attempted.

Abstract 139: Regional Disparities in Mechanical Thrombectomy Utilization for Treatment of Acute Ischemic Stroke in the United States

Background: A current national priority is to understand geographic disparities in mechanical thrombectomy (MT) provision for patients with acute ischemic stroke (AIS). We examine variation in rates of MT by geographic region and urban-rural areas to identify utilization disparities across the United States. Methods: The state-specific annual incidence of AIS in 2019 was determined using data from the Global Burden of Disease Collaborative Network. We determined the number of patients who were admitted with AIS due to thrombosis or embolism of anterior circulation arteries and those who received MT in a particular region/state based on the State Inpatient Database of NIS. The National Inpatient Sample data were used to create national weighted estimates of the size of subject populations, age at admission, length of stay, and discharge status. Results: In the United States, approximately 28,165 MT were performed in 2019, representing 4% of the AIS population. In large central metropolitan areas, the proportion of thrombectomies performed to the AIS patient population was significantly higher than the national estimate (4.34%, P < 0.001); small metropolitan areas and rural settings (micropolitan and noncore) had significantly lower proportions of MT-treated patients with 3.2% and 2.9%, respectively (P < 0.001), when compared with the national estimate. West region had significantly higher proportions of MT-treated patients with 4.3%, compared with the national estimate (P < 0.001), whereas South region had significantly lower proportions with 3.8% (P < 0.001). Conclusions: We found prominent regional disparities in the utilization rates of MT in acute ischemic stroke patients in the United States, which may have implications for Regional Stroke Destination Plans in Rural, Suburban, and Urban Communities.

Abstract TP43: Optimizing System-Wide Nursing Assessment Documentation in the Stroke Population

Background: Stroke centers following AHA guidelines for the treatment of acute ischemic stroke, are challenged by compliance with documentation of vital sign, neuro and neurovascular assessments post thrombolysis interventions. Standardizing documentation in the electronic health record (EHR) increases compliance and reduces patient harm. In a large healthcare system, multiple sites received corrective action findings from regulatory agencies for missed nursing assessments. The centers did not have a documentation workflow aligned with the EHR to capture assessments in the stroke population. Purpose: To create a system-wide documentation workflow that captures nursing assessments in the EHR. Methods: In 2019 a task force of stroke coordinators and clinical informaticists convened to define evidence-based nursing assessments in stroke patients post intervention, define within normal limits for each component, and identify barriers to documentation in the EHR. The EHR was evaluated for component location and other areas in need of optimization. Components were scattered across different EHR locations, leading to missing documentation and assessments were difficult to trend. The task force led the development and implementation of a single EHR location to document nursing assessments. The EHR revisions were implemented in July 2022 after being vetted by system EHR governance, nurse practice council, and stroke coordinator collaborative. Results: A single grouping was developed in the EHR including vitals, focused neurological and neurovascular assessments. This grouping was strategically placed within nursing’s existing workflow. Reference text addressing each element of the grouping and its “within defined limits’ definition were added to align with the organization's documentation standards. To increase visibility of documentation, trending, and the auditing process, a single results view was developed which included all documented assessment components. Conclusion: A system-wide documentation workflow aligned with the EHR optimized documentation workflow, improved visibility of assessments, reduced audit time and regulatory findings. Stroke centers should carefully consider the layout of nursing documentation in the EHR.

Abstract WP3: Serum Glucose Fluctuations is an Independent Predictor of Adverse Outcomes in Patients With Acute Ischemic Stroke Undergoing Endovascular Treatment

Background: Acute hyperglycemia may increase the rate of death or disability among acute ischemic stroke patients undergoing endovascular procedures. Objective: To explore the association between serum glucose fluctuation on post treatment symptomatic intracranial hemorrhage (sICH) and mortality. Methods: We analyzed consecutive acute ischemic stroke patients who underwent endovascular treatment over 30 months at a comprehensive stroke center. Serum glucose levels within the initial 24 hours were used to calculate the mean and standard deviation (SD). Patients were grouped by the standard deviation [SD] of the mean value of serum glucose, whether above or below 25%. Outcomes included sICH, and inpatient mortality, adjusted for confounders which included age, gender, baseline NIHSS, perfusion grade (TICI) intravenous thrombolysis, history of diabetes and HBA1c. Results: A total of 224 patients (mean age was 68.7 years (±14.3); 44.2% were women) underwent endovascular treatment. The proportion of sICH (16.7% vs. 3.28%; p=0.0006) and inpatient mortality (18.6% vs. 7.4%; p=0.0112) were higher in patients with SD exceeding 25. After adjusting for potential confounders, serum glucose SD above 25 was significantly associated with increased rate of sICH (odds ratio [OR] 5.2; 95% confidence interval [CI] 1.5-18.5; p=0.0112) and inpatient mortality (OR 3.5; 95% CI 1.3-9.8; p=0.0154). Conclusion: Serum glucose fluctuations within first 24 hours maybe be therapeutic target due to its association with increased risks of sICH and inpatient mortality following endovascular treatment in acute ischemic stroke.

Abstract WP100: Trends in the Utilization of Intravenous Thrombolysis for Ischemic Stroke in Korea From 2013 to 2022

Introduction: IV thrombolysis is a proven treatment for acute ischemic stroke (AIS), but it is still underutilized in real-world clinical practice. Using a nationwide multicenter stroke registry, we aimed to determine whether there are significant trends in the rate of IV thrombolysis in different patient populations. Methods: This study assessed patients with AIS or transient ischemic attack (TIA) registered prospectively in the Clinical Research Center for Stroke-Korea (CRCS-K) registry between 2013 and 2022. Trends in IV thrombolysis rate were respectively analyzed for all patients (cohort 1), patients who arrived at the hospital within 4.5 hours of onset (cohort 2), and patients potentially eligible for IV thrombolysis (cohort 3), using joinpoint regression analysis. Trends in IV thrombolysis rates in cohorts 1-3 were further investigated using generalized linear mixed-effects models adjusted for patient characteristics and accounting for hospital heterogeneity. Results: A total of 76535 patients were included in the analysis. The mean age of the patients increased from 67.3 to 69.8 years, and the median time from onset to hospital arrival increased over the 10-year period. During the study period, proportion of patients arriving at the hospital within 4.5 hours of onset and the proportion of patients potentially eligible for IV thrombolysis decreased, especially after 2016. IV thrombolysis rates significantly declined over the 10-year period in cohorts 1-3, with a pronounced decrease in the treatment rate in potentially IV thrombolysis eligible patients from 2013 to 2016 (average annual percent change [95% CI] -4.55% [-5.66% to -3.46%] in cohort 1; -2.63% [-3.95% to -1.34%] in cohort 2; -1.33% [-2.06% to -0.49%] in cohort 3). In the multivariable model, patients who arrived in 2022 were less likely to receive IV thrombolysis compared to patients who arrived in 2013 (adjusted odds ratio [95% CI], 0.83 [0.75 - 0.93]). Conclusions: Utilization of IV thrombolysis has declined over the decade in Korea, even accounting for the decline in the number of patients who are candidates for the treatment. Urgent interventions to increase IV thrombolysis rates are needed to improve acute stroke care.

Abstract WP197: Poor Venous Outflow is Associated With Ischemic Core Growth During Transfer in Acute Ischemic Stroke Patients With a Large Vessel Occlusion

Introduction: Thrombectomy is an effective therapy for the treatment of acute ischemic stroke due to large vessel occlusion (AIS-LVO). Patients with small ischemic cores have the most favorable outcomes after thrombectomy, and core growth during the transfer from a primary to a comprehensive stroke center (PSC to CSC) can lead to worse outcomes. We determined if poor venous outflow (VO) prior to transfer to a CSC predicts ischemic core growth in AIS-LVO. Methods: AIS-LVO patients in the prospective CRISP2 study who had a CTA and CT perfusion (CTP) at a PSC and a follow-up CTP or MRI immediately after transfer to the CSC were screened for enrollment. VO was measured on CTA at the PSC using cortical venous opacification score (COVES). COVES 0-2 was defined as unfavorable VO (VO-) and 3-6 was defined as favorable (VO+). Ischemic core was determined on CTP at the PSC and DWI MRI or CTP at the CSC. The primary outcome was inter-hospital ischemic core growth rate defined as a ratio between core growth and time between scans. Results: 174 patients were included; 64% had VO+ and 36% had VO-. VO- patients had larger baseline ischemic core volumes (median 10.5 [IQR 0-23.3] vs 0 [IQR 0-11] ml, p=0.006) and worse CTA collaterals (TAN median 1.82 [IQR 0-3] vs 2.26 [IQR 1-3], p=0.0002). VO- experienced greater ischemic core growth (median 19.6 ml [IQR 2.5-38] vs 8.8 ml [IQR 1.5-21.7], p=0.005) and higher growth rate (median 5.7 ml/hr [IQR 1.4-13.4] vs 2.8 ml/hr [IQR 0.4-7.5], p=0.007) during transfer as described in Figure 1 . Conclusions: In AIS-LVO patients, VO- prior to transfer to a comprehensive stroke center correlated with increased ischemic core growth and more rapid core growth rates. These results have implications for neuroprotection trial design.

Abstract WP42: Transition to Tenecteplase: A Regional Experience

Background: Timely recognition and treatment of acute ischemic stroke is well-supported to promote better outcomes. Historically, alteplase has been the drug of choice for thrombolytic treatment, and while it is an excellent drug, there were barriers that would routinely come up during administration. Following the results of several studies that compared alteplase to tenecteplase, our leadership team decided to initiate the transition to tenecteplase within our region, spanning several states with approximately 40 hospitals. Purpose: The purpose of this clinical initiative was to implement tenecteplase as the primary thrombolytic in acute ischemic stroke and evaluate time to treatment (door in door out [DIDO] and door to needle [DTN]). Methods: Following the approval by leadership, the first step was identification of stakeholders at facility, market, service-line, and regional levels and initiation of bi-weekly meetings. The project relied heavily on facility-level structure that facilitates stroke quality improvement. We were able to utilize market specific stroke databases to understand historical data and to monitor ongoing success and complications. Results: Post-implementation, several positive changes were noted, which are visualized in the graphs. Conclusions: Through reduction of DIDO, treatment is initiated sooner to reperfuse at-risk brain tissue. Further evaluation is needed on the correlation between the transition and decreased length of stay, but we recognize tenecteplase has been shown to have a better rate of recanalizing large vessel occlusions, potentially resulting in less disability and shorter hospitalizations.

Tenecteplase for Acute Ischemic Stroke Thrombolysis: Practical Considerations and Real-World Implementation.

The only FDA-approved medical treatment for acute ischemic stroke (AIS) is alteplase (commonly referred to as "tPA"). The utilization of a newer fibrinolytic agent, tenecteplase, in routine stroke care is increasing because of recent clinical trial findings, streamlined clinical workflows, and cost-effectiveness. The stroke community is monitoring this development with considerable interest and special attention to the following questions: (1) Does the current evidence support superiority or noninferiority of tenecteplase compared with standard-of-care alteplase? (2) What are the ramifications of off-label treatment with tenecteplase? (3) And what are the real-world considerations when transitioning from alteplase to tenecteplase for AIS thrombolysis? This commentary provides a practical synthesis of the current evidence and discusses our institutional experience with tenecteplase including treatment considerations, off-label use, patient consent, stroke center accreditation, and cost savings. Necessary "Code Stroke" workflow changes to ensure a safe transition from alteplase to tenecteplase are detailed.

Abstract 25: Intravenous Thrombolysis for Acute Ischemic Stroke in Patients With Recent Direct Oral Anticoagulant Use: A Systematic Review and Meta-Analysis

Introduction: Intravenous thrombolysis (IVT) is efficacious treatment of acute ischemic stroke (AIS). However, certain circumstances associated with increased bleeding risk, such as recent direct oral anticoagulation (DOAC) intake limits its use. Nonetheless, emerging evidence has shown promising results in this patient group. We investigated the safety and efficacy of IVT in patients with AIS and recent DOAC use. Methods: We conducted systematic review and meta-analysis of proportions evaluating IVT with recent DOAC use. Outcomes of interest were symptomatic intracranial hemorrhage (sICH), any ICH, serious systemic bleeding (SSB), and 90-day functional independence (mRS 0-2). Moreover, we calculated pooled odds ratios (OR) for each outcome using a random effect meta-analysis to compare the rates between the patients with DOAC and non-DOAC upon IVT. Ultimately, we completed a sensitivity analysis for idarucizumab, NIHSS, and the timing of DOAC administration. Results: Our meta-analysis included 14 studies with 247079 patients (3610 in DOAC and 243469 in non-DOAC). In the DOAC group, the rate of sICH was 3% (95%CI 3 - 4%), any ICH was 12% (95%CI 7 - 19%), SSB 0.7% (95%CI 0 - 1%), and 90-day mRS 0-2 was 57% (95%CI 43 - 70%). No difference in the rates of sICH (3.4vs.3.5%; OR=0.95; 95%CI 0.67 - 1.36), any ICH (17.7vs.17.3%; OR=1.23; 95%CI 0.61 - 2.48), SSB (0.7vs.0.6%; OR=1.27; 95%CI 0.79 - 2.02), and 90-day mRS 0-2 (46.4vs.56.8%; OR=1.21; 95%CI 0.400 - 3.67) was found between DOAC and non-DOAC groups. Subgroup analysis revealed no significant difference in the sICH rate between idaricuzumab and no idaricizumab administration prior to IVT [Figure 1]. Conclusions: Our analysis demonstrated no significant difference in functional independence and hemorrhagic complication rates in AIS patients treated with IVT with recent DOAC compared to the no-DOAC group. Further prospective randomized clinical trials are needed to shed more light on this topic.

Functional long-term outcome following endovascular thrombectomy in patients with acute ischemic stroke

Endovascular thrombectomy (EVT) is the most effective treatment for acute ischemic stroke caused by large vessel occlusion (LVO). Yet, long-term outcome (LTO) and health-related quality of life (HRQoL) in these patients have rarely been addressed, as opposed to modified Rankin scale (mRS) recordings. We analysed demographic data, treatment and neuroimaging parameters in 694 consecutive stroke patients in a maximum care hospital. In 138 of these patients with respect on receipt of written informed consent, LTO and HRQoL were collected over a period of 48 months after EVT using a standardised telephone survey (median 2.1 years after EVT). Age < 70 years (OR 4.82), lower NIHSS on admission (OR 1.11), NIHSS ≤ 10 after 24 h (OR 11.23) and complete recanalisation (mTICI3) (OR 7.79) were identified as independent predictors of favourable LTO. Occurrence of an infection requiring treatment within the first 72 h was recognised as a negative predictor for good long-term outcome (OR 0.22). Patients with mRS > 2 according to the telephone survey more often had complaints regarding mobility, self‐care, and usual activity domains of the HRQoL. Our results underline a sustainable positive effect of effective EVT on the quality of life in LVO stroke. Additionally, predictive parameters of outcome were identified, that may support clinical decision making in LVO stroke.

Abstract TP307: oxLDL Preconditioning Intensifies Ischemic-Like Injury Mediated Alterations in Human Male Brain Endothelial Cell Tight Junction Protein Levels and Proinflammatory Mediators

Introduction: Acute ischemic stroke (AIS) triggers endothelial activation and induces cerebrovascular inflammation which can result in vascular function and integrity loss leading to worsened stroke outcome. A clinically correlated risk factor for stroke shown to mediate vascular dysfunction and injury is elevated levels of oxidized low density lipoprotein (oxLDL). We hypothesized that oxLDL would exacerbate acute ischemic injury mediated alteration of endothelial proinflammatory mediator and integral barrier protein levels. Methods: Primary adult male human brain microvascular endothelial cells (HBMEC) were preconditioned with human oxLDL (50 or 100ug/dL; 6, 12, 24, or 36h) or vehicle, using a serum dose reported in AIS patients. HBMECs were then exposed to normoxia (21% O 2 ) or ischemic-like injury, hypoxia plus glucose deprivation (HGD; 1% O 2 ), for 3 or 6h. HBMEC levels or expression of barrier markers, adhesion molecules, and inflammatory mediators were examined using qRT-PCR, in cell western, and FIJI mediated immunocytochemical analysis. Secondary analysis was performed on RNA sequencing of adult male aortic endothelial cells (HAoECs) exposed to oxLDL (50ug/mL; 3, 6, 12, 24h) obtained from GEO dataset GSE13139. Results: HGD injury concomitantly decreased HBMEC claudin-5, occludin, and ZO-1 as well as increased IL-1b, ICAM-1, VCAM-1, iNOS, and TNF-a. OxLDL exacerbated an HGD mediated decrease in HBMEC barrier levels and increase in proinflammatory levels in a dose and time dependent manner. HAoEC barrier, adhesion, and proinflammatory levels were not altered by oxLDL. Conclusion: OxLDL may preferentially alter brain endothelial barrier and proinflammatory levels, as opposed to aortic endothelial cells in dose and time dependent manner. Mitigating the effect of oxLDL on brain endothelial permeability and inflammation, possibly via receptor inhibition may be a novel, viable therapeutic target in the treatment of AIS.

Abstract WP25: Eptifibatide in Acute Ischemic Strokes Without Large Vessel Occlusions

Background: Platelet glycoprotein IIb/IIIa inhibitors are currently being researched for patients with acute ischemic stroke (AIS), however there is no consensus on which inhibitor or dose is both safe and effective. Tirofiban has recently been studied, however it was associated with an increased risk of intracranial bleeding. In this study we share our experience using eptifibatide given it has shown to be as effective as tirofiban with a better safety profile. Methods: In this multi-center retrospective analysis, we screened 102 patients who received an eptifibatide bolus of 135 mcg/kg followed by 0.5 mcg/kg/min infusion and 332 patients treated with usual stroke care between December 2022 and May 2023. Patients were excluded if the NIHSS on presentation but within 24 hours of last known well was less than 3 or if the patient had a large vessel occlusion (LVO). There were 7 and 31 patients included in the eptifibatide and usual care group respectively. Our primary endpoint was change in NIHSS from admission to discharge. Our safety endpoints were symptomatic ICH and any ICH. Results: No patients included in the study experienced a symptomatic ICH. The median time of eptifibatide infusion was 24 hours with some patients receiving the infusion for multiple days. Conclusion: While larger studies are needed to confirm our findings, eptifibatide may be safe and effective in the treatment of AIS without LVO.

Abstract WP29: Early Adopter of Intravenous Tenecteplase: Two Year Clinical Experience in a Non-Academic Suburban Comprehensive Stroke Center for Acute Ischemic Stroke Treatment

Background: The most recent American Heart Association/American Stroke Association acute ischemic stroke guidelines recognize tenecteplase (TNK) as an alternative to alteplase (ALT) for acute ischemic stroke (AIS) treatment. TNK has a longer half-life, and is given as a single intravenous bolus compared to the complex and cumbersome ALT administration. A switch to TNK was implemented at our Comprehensive Stroke center (CSC) after a rigorous training of nurses and providers on May 1, 2021. We sought to evaluate the comparative performance of two thrombolytics over the period of last two years of ALT and first two years on TNK use. Methods: This was a retrospective review of prospectively collected database of consecutive AIS patients treated with ALT between May 2019 to April 2021 and those who received TNK from May 2021 to April 2023 at our CSC. Data samples were analyzed with respect to baseline patient characteristics, stroke severity, Door to Needle (DTN) time, 90 day Modified Rankin Scores (MRS), complications, and cost savings. Statistical analyzes were used for between group comparisons (SPSS). Results: A total of 115 patients were treated with ALT and 134 - with TNK. There were no significant differences in baseline characteristics or stroke severity between the groups (mean NIHSS of 10 for both). The mean DTN was 53.0 minutes for ALT and 41.5 minutes for TNK (p&lt;0.001). There was a strong trend towards improved 90-day clinical outcomes for TNK-treated patients (mRS 2.5 vs 3.1, p=0.06). No significant differences in rates of symptomatic Intracerebral Hemorrhage (SICH) were observed between two groups (2.6% ALT vs 2.9% TNK). Estimated cost savings of TNK use over two year period were $75,102. Conclusion: Our real-world data suggests that intravenous TNK for AIS appears to be safe and may result in improved clinical outcomes and substantial cost savings compared to ALT.

Abstract WP65: Impact of Artificial Intelligence on Acute Ischemic Stroke Treatment in a Large Academic Healthcare System

Introduction: We aimed to evaluate the impact of the implementation of a stroke triage artificial intelligence (AI) software on a large academic healthcare system. Methods: A retrospective study was conducted in our spoke and hub network comparing equal corresponding periods of pre- and post- Viz.ai implementation between January 2021 and December 2022. Door to needle, door to puncture (DTP), successful reperfusion rates, transfer rates, and clinical outcomes at discharge were compared. Results: The analysis encompassed a total of 5,456 patients including 2313 pre- and 2275 post-Viz.ai patients across 11 spokes and 416 pre- and 452 post-Viz.ai patients across 4 hubs. Among 868 patients undergoing EVT at the 4 hubs, there was no differences in baseline data except for a higher baseline NIHSS score in the post Viz.ai group. We found an overall absolute reduction of transfers by 60 cases equating to a statistically significant decrease of 2.3% (P=0.04). The results showed an overall decrease by 13.5 minutes (8.1%) which was not statistically significant (P=0.3). There was an overall statistically significant decrease of 6 minutes (9.5%) in DTP times from 63 (23-98) minutes to 57 (23-79) minutes (P=0.01). No other differences in outcomes were noted between both groups. Conclusion: The automatic AI software was able to show a notable impact in our hub and spoke mature network driven by decrease of unnecessary transfers, DIDO and DTP. These data support the role of AI software as an effective triaging tool in the stroke and hub networks. More studies are needed to confirm these results.

Abstract 144: Value of CT Perfusion Imaging Among Patients With Minor Stroke

Introduction: CTP has increasingly been incorporated into the evaluation of all patients with suspected acute ischemic stroke (AIS), including those with minor symptoms. We aimed to assess the incremental value of CTP in acute treatment decision-making among patients with low NIHSS. Methods: We performed a retrospective cohort study of all patients who underwent CTP upon presentation to the ED at three academic, urban hospitals in Philadelphia, PA between January 1, 2022 and December 31, 2022. We collected data on initial NIHSS score, AIS treatment decisions, subsequent neuroimaging, and final diagnosis. Results: There were 531 patients with a median age of 64.5 years (IQR 54-73) and 56% were women. 73% were Black or African American, 20% White, and 4% Asian. Frequency of CTP imaging by initial NIHSS score is presented in the Figure. Among 90 patients (16.9%) with NIHSS≤2, CTP imaging was cited as justification for AIS treatment (thrombolysis, thrombectomy, or both) in 0 (0%, 95% CI: 0-4%). Specifically, among 41 patients (7.7%) with NIHSS≤1, 0 received thrombolysis or thrombectomy, and 12 (29.2%) were ultimately diagnosed with AIS on CT/MRI. Among 49 with NIHSS=2 (9.2%), 2 patients received thrombolysis (based on clinical exam, CTP was normal) and one later underwent thrombectomy based on clinical decompensation with repeat NIHSS=7, and 28.6% had AIS on CT/MRI. Meanwhile, among 33 patients with NIHSS=3, acute treatment was given to 3 and CTP influenced AIS treatment decisions in 2 (6.1%). Among 59 patients with NIHSS=4, acute treatment was given to 4 and CTP influenced decision-making in 3 (5.1%). CTP mismatch ratio was &gt; 1.7 in all 5 patients who received acute treatment and had NIHSS of 3 or 4. Conclusions: CTP is frequently performed in patients with low NIHSS. It had limited impact on acute treatment decisions, notably none among those with NIHSS≤2, suggesting that CTP may be over-utilized in this subset of patients with AIS.

Abstract TP207: Endovascular Treatment in the Late Time Window: Strict Perfusion Imaging Screening Criteria in Case Selection

Background and purpose: Clinical-imaging mismatch or perfusion imaging mismatch criteria per DAWN (Clinical Mismatch in the Triage of Wake Up and Late Presenting Strokes Undergoing Neurointervention With Trevo) or DEFUSE-3 (Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke), respectively were recommended for case selection for endovascular treatment (EVT) of acute ischemic stroke (AIS) in the late time window outside 6 hours of stroke onset. We aimed to compare the clinical functional outcomes in EVT patients with and without strict perfusion imaging screening criteria in the late time window. Methods: AIS patients with anterior circulation large vessel occlusion (LVO) presenting within 6 to 24h hours after symptom onset were selected from a retrospectively collected thrombectomy cohort database (RESTORE). According to the imaging criteria of DAWN and DEFUSE-3, we compared proportions of patients with a favorable functional outcome (defined as a modified Rankin Scale [mRS] score of 0-2) at 90 days between the DAWN or DEFUSE-3 patients (D/D) and the non-DAWN or DEFUSE-3 (non-D/D) patients. Results: Among 265 adult patients with anterior circulation LVO who received EVT within 6 to 24 hours after symptom onset, 142 patients met either DAWN or DEFUSE-3 imaging criteria. D/D group independently predicted favorable functional outcome at 90 days (50.7% vs. 35.0%, aOR 0.514; 95% CI 0.273-0.966, p=0.039) adjusted for age, sex, previous stroke, hypertension, atrial fibrillation, coronary heart disease, pre-EVT collateral score, successful recanalization, onset to CT time. Conclusions: In AIS patients with anterior circulation LVO in the late time window, our real world data support the guideline that DAWN or DEFUSE-3 imaging criteria are strongly recommended for EVT case selection.

Abstract WP200: Endovascular Therapy for Isolated Carotid Occlusion in the Neck

Background and Study Purpose: Existing guidelines on endovascular treatment (EVT) of acute ischemic stroke do not include isolated cervical internal carotid artery occlusions (CICAO). These occlusions are still treated, but the effect remains unclear. This study aimed to compare the baseline characteristics and treatment outcomes between patients with isolated CICAO and patients who underwent EVT due to occlusions mentioned in guidelines. Methods: A retrospective study was conducted on 1162 patients who underwent EVT due to ischemic stroke at Aarhus University Hospital between June 2017 and June 2022. Univariate analysis of outcomes and baseline characteristics were compared between patients with isolated CICAO and tandem occlusions or isolated CICAO and occlusion of the middle cerebral artery (M1)/intracerebral internal carotid artery (ICA-T). Results: 731 patients were eligible for inclusion. Patients with isolated CICAO were more likely male (67.8% vs 50.9%, p-value = 0.0009) and active smokers (42.2% vs 26.4%, p = 0.0016) compared to patients with M1/ICA-T occlusions where atrial fibrillation (35.5% vs. 23.5%, p = 0.0158) and an equal sex distribution was more frequently seen. The groups showed similar favorable outcomes and mortality. Notably, a statistically significant difference in mortality between patients with isolated CICAO (precent) and M1/ICA-T occlusions (percent) could not be excluded (p = 0.0584). Conclusion: Patients with isolated CICAO and M1/ICA-T occlusions seem to differ in sex, smoking status, and atrial fibrillation. This study did not find any differences between isolated CICAO and tandem occlusions. EVT appears beneficial in patients with isolated CICAO, however randomized-controlled trials are necessary to examine and compare the effect between occlusion sites.

Abstract WP193: Endovascular Thrombectomy for DAWN- and DEFUSE 3 Ineligible Acute Ischemic Stroke Patients: A Systematic Review and Meta-Analysis

Background: The current evidence supports the benefits of endovascular treatment (EVT) in acute ischemic stroke (AIS) with large vessel occlusion (LVO). The DAWN and DEFUSE-3 trials expanded the EVT window up to 24 hours. A few real-world studies explored EVT outcomes in DAWN/DEFUSE-3 ineligible (NDND) patients. Methods: This meta-analysis investigated EVT outcomes in patients with late-window anterior circulation LVO, including both DAWN/DEFUSE-3 eligible (DD) and NDND patients. Nine studies were included, focusing on study characteristics, risk of bias, and outcomes. Results: Baseline characteristics showed comparable age, gender, comorbidities, NIHSS score, and ASPECTS between DD and NDND patients. NDND patients exhibited larger infarct volumes and higher atrial fibrillation rate. Successful reperfusion rates (TICI 2b-3) were comparable between the two groups (OR= 0.86; 95% CI= 0.40, 1.84; p = 0.689), with significant heterogeneity (I 2 = 73%; P = 0.002). Functional independence (90-day mRS score 0-2) was not significantly different between the two groups (OR= 1.12; 95% CI= 0.77, 1.63; p = 0.552) with notable heterogeneity (I 2 = 46%, p = 0.063). Symptomatic intracranial hemorrhage (sICH) rate was lower in the DD group as compared to NDND patients (OR= 0.49; 95% CI= 0.25, 0.93; p = 0.029) with no heterogeneity (I 2 = 0%, p = 0.552). 90-day mortality was lower in the DD group than in the NDND group (OR= 0.55; 95%-CI= 0.37, 0.82; p = 0.004) with no significant heterogeneity (I 2 = 0%, p = 0.536). Conclusion: While this meta-analysis showed comparable rates of functional independence between DD and NDND patients, the potential bias introduced by the higher rates of sICH and mortality in the latter group should prompt great care when offering EVT to NDND patients. Less restricted EVT eligibility criteria might yield positive outcomes in real-world practice in specific patients. However, increased risks of sICH and mortality in NDND patients warrant further investigation to optimize the risk-benefit balance in expanding EVT eligibility criteria.

Abstract TP70: EHR Based System Improves Stroke Alerting Process in the Emergency Department

Background and Issues: Treatment decisions for patients experiencing acute ischemic stroke require complex imaging and evaluation. Specialized teams including Neurologists, pharmacists and CT technicians are alerted to the ED when a patient presents with signs or symptoms of acute ischemic stroke (AIS) to carry out these evaluations. At our facility, these alerts were delivered via a de-identified text message, preventing the collection of data needed for clinical effectiveness and quality improvement work. Purpose: This project's purpose was to improve the Stroke Alert process using Computerized Physician Order Entry (CPOE) to initiate the alert via a HIPAA Compliant Group Messaging (HCGM) application called Haiku. Methods: Haiku is an application available in the hospital’s electronic health record, which allows for retrieval of data unavailable when utilizing the de-identified alerting method. Data on 70 consecutive Stroke Alerts from 6 weeks prior to implementation of the Haiku Stroke Alert were compared to 80 consecutive Stroke Alerts 6 weeks after implementation. A comparison of Door to CT and Door to Needle times in those periods were also compared to ensure the new process did not cause any delays in these metrics. Results: Results showed the CPOE based Haiku Stroke Alert process was easily adopted and allowed for access to data necessary for clinical effectiveness and quality improvement work without causing delays in Door to CT (DTCT) or Door to Needle (DTN) times. Conclusions: In conclusion, this quality improvement project addressed the lack of data available to assess the Stroke Alert process. A new CPOE based alert process utilizing the HCGM app Haiku proved feasible, received positive feed-back from ED team who initiates the alert and the Neurology resident team who receives the alert. The Haiku alert did not appreciably add time to the DTCT or DTN times. This process allows access to comprehensive data that can be used to explore other avenues to improve the hyperacute phase of AIS triage and treatment. The availability of robust Stroke Alert data was the missing foundational element allowing for clinical effectiveness and quality improvement work.

Abstract WP87: To Walk-In or Not to Walk-In: Effects of ED Mode of Arrival on Acute Stroke Treatment and Hospitalization Outcomes in a Large Integrated Healthcare System

Background: Prior studies reported that only half of stroke patients arrived at emergency departments (ED) via emergency medical services (EMS). We sought to assess predictors of ED mode of arrival and its effects on acute stroke care and inpatient outcomes in a large racial-ethnically diverse cohort. Methods: In 2016, we launched a system-wide standardized telestroke program for 21 certified stroke centers. Non-cancelled stroke alerts included those patients who were potential candidates for further workup for acute ischemic stroke treatment. This study cohort included non-cancelled stroke alerts seen by Telestroke in 2021. Assessment included demographics, ED arrival mode , initial NIH Stroke Scale (NIHSS), neuroimaging results, IV thrombolytic, door-to-needle (DTN) time, large vessel occlusion (LVO), thrombectomy referral, hospital length of stay and discharge disposition. Clustered logistic regression was used to evaluate ED arrival mode’s effects on short-term outcomes. Results: Of the 7744 stroke alerts seen by Telestroke in 2021, 3264 (42.2%) were non-canceled. Among these, 2014 (61.7%) were in the early window (0-4.5 hours from last seen well). More of those arriving in the early window came via EMS compared to those seen in the extended window [1625 (80.7%) versus 729 (58.3%) respectively]. Among non-canceled ED stroke alerts, compared to patients who arrived via EMS, walk-in patients were younger, more Hispanic, had lower initial NIHSS scores, longer times for ED to contact Telestroke, slower DTN times, but less mortality [Table]. In multivariate analysis, walk-in patients were less likely to have a DTN time within 30 minutes (OR=0.37, 95% CI 0.25-0.34; p=&lt;0.001). Conclusions: In our cohort, there were several differences between walk-in patients and those who arrived via EMS. Further research is needed to understand these differences, the reasons for choosing walk-in, and whether ED mode of arrival affects clinical outcomes.