Outcomes Of Endovascular Thrombectomy Research Articles

Mechanical thrombectomy by stent retriever for the treatment of arterial ischemic stroke in a pediatric patient with acute lymphoblastic leukemia: A case report

Introduction: Arterial ischemic stroke (AIS) caused by occlusion of large vessels in childhood is a devastating rare condition that can contribute to long-term disabilities. Childhood leukemia is identified as a recognized risk factor for ischemic strokes. Mechanical thrombectomy is standard of care for large vessel occlusions in adults. However, there are still no definite recommendations regarding application and outcomes of endovascular thrombectomy and the devices used for pediatric patients with arterial ischemic stroke. Case presentation: We report a 13-year-old female with acute lymphoblastic leukemia who developed AIS due to thrombosis in the left internal carotid and proximal middle cerebral artery in the induction phase of treatment. The patient underwent successful mechanical thrombectomy via Solumbra by using “Embolus Retriever with Interlinked Cages (ERIC)” stent retriever and Sofia plus catheter which resulted in successful recanalization of ICA and MCA. Discussion: Selected pediatric patients with AIS due to large vessel occlusions can benefit from mechanical thrombectomy. Although the recently published literature demonstrated the efficacy and safety of MT in children, strong guideline recommendations are still absent. At present, the last AHA/ASA guidelines for early management of AIS recommends intravenous thrombolysis and endovascular therapy in adults, whereas controversy still exists in children. An urgent approach within the defined therapeutic time frame and a multidisciplinary team specialized in pediatric stroke with professional trained interventional neuroradiologist is essential for achieving optimal results. Conclusion: Mechanical thrombectomy provides promising results with high rates of arterial recanalization and favorable outcomes in pediatric patients with AIS.

Endovascular thrombectomy versus medical management for patients with large vessel stroke and infective endocarditis

BackgroundThe safety and efficacy of endovascular thrombectomy (EVT) for large vessel occlusion (LVO) strokes associated with infective endocarditis (IE) compared with medical management (MM) is unclear.MethodsIn this nationwide analysis of...

Association between heart failure and cerebral collateral flow in large vessel occlusive ischemic stroke

BackgroundCerebral collateral circulation plays a crucial role in determining the extent of brain ischemia in large vessel occlusive (LVO) stroke. Heart failure (HF) is known to cause cerebral hypoperfusion, yet the relationship between HF and robustness of collateral flow has not been well described. MethodsConsecutive patients with middle cerebral and/or internal carotid LVO who underwent endovascular thrombectomy (EVT) between 2012 and 2020 were included. Single-phase head CTA prior to EVT was used to assess collateral status (poor <50 % filling; good ≥50 %). Classification of HF by left ventricular ejection fraction (LVEF) on echocardiogram was used where HF with reduced ejection fraction (HFrEF) had LVEF ≤40 %, HF with preserved EF (HFpEF) had LVEF ≥50 % with evidence of structural heart disease, and no HF had LVEF≥50 % without structural heart disease. Multivariable logistic regression analyses were performed to evaluate the association between HF and poor collaterals. ResultsWe identified 235 patients, mean age was 69 ± 15 years; initial NIHSS was 18 ± 7. Of these, 107 (45.5 %) had HF and 105 (44.7 %) had poor collaterals. Those with HF were likely to have poor collaterals compared to those without HF (56.1 % vs 35.2 %, P = 0.001). There was a dose-dependent relationship between EF and poor collaterals: adjusted odds of poor collaterals were 1.63 and 2.45 in HFpEF and HFrEF, compared to those without HF (trend P = .018). ConclusionPatients with HFrEF are more likely to have poor cerebral collaterals. Further study is needed to explore the pathomechanisms. Optimization of HF may improve cerebral collaterals and enhance EVT outcomes.

Age and Functional Outcomes in Patients With Large Ischemic Stroke Receiving Endovascular Thrombectomy

Randomized clinical trials have demonstrated the efficacy and safety of endovascular thrombectomy for acute ischemic stroke with large infarct. Patients older than 80 years with large infarct are commonly encountered in clinical practice but underrepresented in randomized clinical trials. To provide an age-based analysis of functional outcomes in endovascular thrombectomy for acute ischemic strokes with large infarct. This retrospective multicenter cohort study included patients from the German Stroke Registry who received endovascular thrombectomy for acute ischemic stroke with large infarct at 1 of 25 German stroke centers between May 2015 and December 2021. Patients with acute ischemic stroke due to anterior circulation large vessel occlusion and large infarct were included. Large infarct was defined as an Alberta Stroke Program Early Computed Tomography Score of 0 to 5. Patients were subdivided by age to evaluate its association with functional outcomes. Age. Primary outcomes were independent ambulation (90-day modified Rankin Scale score of 0-3) and mortality (90-day modified Rankin Scale score of 6). A total of 408 patients with large infarct were included (217 women [53.2%]; median [IQR] age, 75 [64-83] years). The rate of independent ambulation decreased from 56.4% in patients aged 60 years and younger (44 of 78 patients) to 15.1% in patients older than 80 years (19 of 126 patients) (P < .001), while mortality increased from 15.4% (12 patients) to 64.3% (81 patients) (P < .001). Being older than 80 years was associated with lower rates of independent ambulation (adjusted odds ratio [aOR], 0.44; 95% CI, 0.23-0.82; P = .01) and higher mortality (aOR, 2.75; 95% CI, 1.61-4.72; P < .001). A final modified Thrombolysis in Cerebral Infarction grade of 2b or 3 was associated with higher rates of independent ambulation (aOR, 4.95; 95% CI, 2.14-11.43; P < .001), independent of age and without significant interaction (aOR, 0.69; 95% CI, 0.35-1.34; P = .27). In this cohort study of patients with acute ischemic stroke and large infarct, age was associated with functional outcomes. Patients older than 80 years had poor prognosis with high mortality but with sizeable differences depending on additional baseline and treatment characteristics. While it does not seem justified to apply a fixed upper age limit for endovascular thrombectomy, these results could assist clinicians in making informed treatment decisions in older patients with large ischemic stroke.

Impact of stroke imaging selection modality on endovascular thrombectomy outcomes in the early and extended time windows: A meta-analysis.

The effect of imaging selection modality on endovascular thrombectomy (EVT) clinical outcomes in patients with acute ischemic stroke due to large vessel occlusion (AIS-LVO) remains unclear. This study aims to compare post-EVT outcomes in patients with AIS-LVO who underwent basic imaging (computed tomography with or without computed tomography angiography) and advanced imaging (computed tomography perfusion or magnetic resonance imaging) in early and late time windows. A systematic literature search was conducted on PubMed, Cochrane Library, and Embase databases from inception until June 10, 2023. Studies investigating the relationship between the imaging selection modality and post-EVT outcomes in patients with AIS-LVO were retrieved. A random-effects model was used to pool the effect estimates of successful reperfusion, symptomatic intracranial hemorrhage (sICH), functional independence, and mortality. The meta-analysis was performed using Review Manager software v.4.3, and the outcomes were assessed using odds ratios (ORs) and 95% confidence intervals (CIs). A total of 13 non-randomized observational studies, comprising 19,694 patients, were included in this meta-analysis. In the early time windows, AIS-LVO patients receiving advanced imaging demonstrated a higher likelihood of functional independence (OR, 1.25, 95% CI, 1.08-1.46) and a lower risk of mortality (OR,.73 95% CI,.61-.86) compared to those receiving basic imaging. In the extended time windows, AIS-LVO patients undergoing advanced imaging had a lower mortality rate (OR,.79, 95% CI,.68-.92). Regardless of the time of onset, there were no significant differences between the two groups in terms of sICH or successful reperfusion. Advanced imaging combined with EVT may achieve better clinical outcomes in patients with AIS-LVO. Further high-quality studies are needed to validate these findings.

Impact of Direct Oral Anticoagulant Levels on Functional Independence Following Endovascular Thrombectomy in Patients With Atrial Fibrillation

Background In direct oral anticoagulant (DOAC) users with stroke due to large artery occlusion, endovascular thrombectomy is an effective treatment when intravenous thrombolytic therapy is unsuitable. The purpose of this study is to investigate the association between emergent DOAC levels and endovascular thrombectomy outcomes. Methods Participants with atrial fibrillation, who had a premorbid modified Rankin Scale score of ≤3 and had undergone endovascular thrombectomy for acute stroke, were enrolled. Drug levels upon hospital arrival were measured in the prestroke DOAC users. Head noncontrast computed tomography and computed tomographic angiography images were used to quantify thrombus permeability. The primary outcome was functional independence at 3 months (modified Rankin Scale 0–2 or a return to premorbid status for patients with a premorbid modified Rankin Scale of 3). Results The study included 250 patients (antithrombotic agent nonusers, 42.0%; oral anticoagulant users, 34.0%; and antiplatelet users, 24.0%). The primary outcomes did not differ among the 3 groups. Among oral anticoagulant users, 78.8% were DOAC users. Of the 59 DOAC users with available drug level measurements, 62.7% had low levels (&lt;50 ng/mL). Low‐level patients were less likely to achieve functional independence than high‐level patients (adjusted odds ratio, 0.26 [0.08–0.87]). Compared with antithrombotic nonusers, oral anticoagulant users with therapeutic anticoagulation were more likely to achieve functional independence (adjusted odds ratio, 2.83 [1.18–6.78]), whereas those with inadequate anticoagulation did not. Symptomatic intracerebral hemorrhage occurred in 3 DOAC users in the low‐level group (8.1%), 1 DOAC user in the high‐level group (4.5%), and 4 antithrombotic nonusers (3.8%). Thrombus permeability was similar between antithrombotic nonusers and low‐ or high‐level DOAC users. Conclusion Among patients who underwent DOAC therapy and endovascular thrombectomy, those with low DOAC levels were less likely to achieve functional independence. Furthermore, oral anticoagulant users with therapeutic anticoagulation displayed better functional outcomes than antithrombotic nonusers.

Outcomes and differences by occluded vessel after endovascular thrombectomy for isolated medium vessel occlusions

BackgroundThe outcomes of endovascular thrombectomy (EVT) for medium vessel occlusions (MeVOs) of specific vascular territories remain unknown. We aimed to investigate EVT outcomes by MeVO locations using the data from an ongoing international multicenter registry. MethodsPatients with isolated MeVO who underwent EVT between January 2013 and December 2022 were retrospectively analyzed. Isolated MeVO was defined as an occlusion of the A2 or A3 (A2/A3), M2 or M3, and P2 or P3 (P2/P3). Outcomes included a 90-day modified Rankin score (mRS) of 0–2, successful recanalization (modified Thrombolysis in Cerebral Infarction score ≥ 2b), early neurological deterioration (END) or improvement (ENI), and 90-day mortality. END was defined as a worsening of ≥4 points from the baseline National Institutes of Health Stroke Scale (NIHSS) score within 24 h of EVT, while ENI was defined as an improvement of ≥4 points from the baseline NIHSS score within 24 h of EVT. Results1744 MeVOs included. Compared to M2 occlusions (n = 1542, 88.4%), A2/A3 (n = 36, 2.1%) occlusions had lower odds of 90-day mRS 0–2 (adjusted odds ratio [aOR] 0.30, 95% confidence interval [CI] 0.11–0.80), and P2/P3 occlusions (n = 49, 2.8%) had lower odds of successful recanalization (aOR 0.19, 95% CI 0.07–0.50), and higher odds of END (aOR 3.53, 95% CI 1.35–9.25). Other outcomes showed no significant differences. ConclusionsA2/A3 occlusions were more likely to have worse outcomes compared to M2 occlusions after EVT for patients with isolated MeVOs.

The value of cardiopulmonary comorbidity in patients with acute large vessel occlusion stroke undergoing endovascular thrombectomy: a retrospective, observational cohort study

BackgroundChronic lung and heart diseases are more likely to lead an intensive end point after stroke onset. We aimed to investigate characteristics and outcomes of endovascular thrombectomy (EVT) in patients with acute large vessel occlusion stroke (ALVOS) and identify the role of comorbid chronic cardiopulmonary diseases in ALVOS pathogenesis.MethodsIn this single-center retrospective study, 191 consecutive patients who underwent EVT due to large vessel occlusion stroke in neurological intensive care unit were included. The chronic cardiopulmonary comorbidities and several conventional stroke risk factors were assessed. The primary efficacy outcome was functional independence (defined as a mRS of 0 to 2) at day 90. The primary safety outcomes were death within 90 days and the occurrence of symptomatic intracranial hemorrhage(sICH). Univariate analysis was applied to evaluate the relationship between factors and clinical outcomes, and logistic regression model were developed to predict the prognosis of ALVOS.ResultsEndovascular therapy in ALVOS patients with chronic cardiopulmonary diseases, as compared with those without comorbidity, was associated with an unfavorable shift in the NHISS 24 h after EVT [8(4,15.25) versus 12(7.5,18.5), P = 0.005] and the lower percentage of patients who were functionally independent at 90 days, defined as a score on the modified Rankin scale of 0 to 2 (51.6% versus 25.4%, P = 0.000). There was no significant between-group difference in the frequency of mortality (12.1% versus 14.9%, P = 0.580) and symptomatic intracranial hemorrhage (13.7% versus 19.4%, P = 0.302) or of serious adverse events. Moreover, a prediction model showed that existence of cardiopulmonary comorbidities (OR = 0.456, 95%CI 0.209 to 0.992, P = 0.048) was independently associated with functional independence at day 90.ConclusionsEVT was safe in ALVOS patients with chronic cardiopulmonary diseases, whereas the unfavorable outcomes were achieved in such patients. Moreover, cardiopulmonary comorbidity had certain clinical predictive value for worse stroke prognosis.

Endovascular Thrombectomy for Carotid Pseudo-Occlusion in the Setting of Acute Ischemic Stroke: A Comparative Systematic Review and Meta-analysis.

The effective treatment for patients with acute ischemic stroke (AIS) with cervical internal carotid pseudo-occlusion (cICA-PO) requires comprehensive research on the safety and outcomes of endovascular thrombectomy (EVT). However, there are limited data available, highlighting the need for further research to ensure better treatment strategies and improve the quality of care for these patients. This study aims to assess the management and outcomes in this population group compared with patients with true carotid occlusion. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines, a comprehensive systematic review was conducted by using PubMed, Embase, Web of Science, and Scopus from database inception to November 2023. The size of the included studies ranged from 16 patients to 146 patients. Through the 4 full-text articles, a total of 259 patients were collected. We compared outcomes between patients with cICA-PO compared with patients with true carotid occlusions undergoing EVT due to AIS. We excluded studies with patients with carotid pseudo-occlusion without stroke, review articles, duplicate studies, overlapped data that included the same patients presented in another included study, case reports, case series with fewer than 5 patients, and meeting abstracts that did not contain the outcomes of interest. We did not pose any limitations regarding sample size or patient characteristics. We utilized the R statistical software (V.4.3.1; R package meta) to conduct the analysis of all the data obtained. We calculated the OR for binary variables, and the corresponding 95% CI. To synthesize the data, random-effect models, as well as forest plots were generated to visually represent the synthesis of the data. Additionally, we assessed heterogeneity by using Cochran Q and I 2 tests. A P value < .05 for the Q statistic or I 2 more than 50% suggests notable heterogeneity. Based on a small number of studies (<10), the assessment of publication bias could not be reliably performed. This meta-analysis encompassed data from 4 studies. Patients with cICA-PO and AIS who underwent EVT (n = 135) exhibited lower rates of functional independence (OR = 0.35; 95% CI, 0.20-0.61; P < .001) compared with patients with true occlusions (n = 103), as well as successful recanalization rates (OR = 0.39; 95% CI, 0.20-0.74; P = .004). In addition, the cICA-PO group experienced higher mortality and symptomatic intracranial hemorrhage (sICH) compared with the group with true carotid occlusions (OR = 2.62; 95% CI, 0.21-7.24; and OR = 2.23; 95% CI, 1.00-4.95; P = .049, respectively). Individual patient data were not available. Studies were a retrospective design and some of the studies had small sample sizes. The included studies in our meta-analysis did not exclude patients with tandem occlusions that might influence the results of the comparison. Compared with patients with true carotid occlusion, the cICA-PO group with AIS undergoing EVT presented poor outcomes with lower functional independence and successful recanalization, as well as higher sICH and mortality rates.

Periprocedural intravenous heparin in patients with acute ischemic stroke treated with endovascular thrombectomy after intravenous thrombolysis.

The benefit-to-risk ratio of periprocedural heparin in patients treated with endovascular thrombectomy (EVT) after intravenous thrombolysis (IVT) remains unclear. This study aimed to evaluate the potential effects of periprocedural heparin on clinical outcomes of EVT after IVT. The authors retrospectively analyzed patients from multicenter studies treated with EVT after IVT in the anterior circulation. The endpoints were unfavorable outcome (defined as modified Rankin Scale score ≥ 3 at 90 days), 90-day mortality, symptomatic intracranial hemorrhage (SICH), successful recanalization, and early neurological deterioration. Patients were divided into two groups based on whether they were treated with heparin (heparin-treated group) or not (untreated group), and the efficacy and safety outcomes were compared using multivariable logistic regression models and propensity score-matching methods. Among the 322 included patients (mean age 67.4 years, 54.3% male), 32% of patients received periprocedural heparin. In multivariable analyses, the administration of periprocedural heparin was a significant predictor for unfavorable outcome (OR 2.821, 95% CI 1.15-7.326; p = 0.027), SICH (OR 24.925, 95% CI 2.363-780.262; p = 0.025), and early neurological deterioration (OR 5.344, 95% CI 1.299-28.040; p = 0.029). Regarding successful recanalization and death, no significant differences between the groups were found after propensity score matching. The results showed that periprocedural heparin is associated with an increased risk of unfavorable outcomes and SICH in patients treated with EVT after IVT. Further studies are warranted to evaluate the utility and safety of periprocedural heparin.

Endovascular Thrombectomy Treatment Effect in Direct vs Transferred Patients With Large Ischemic Strokes

Patients with large ischemic core stroke have poor clinical outcomes and are frequently not considered for interfacility transfer for endovascular thrombectomy (EVT). To assess EVT treatment effects in transferred vs directly presenting patients and to evaluate the association between transfer times and neuroimaging changes with EVT clinical outcomes. This prespecified secondary analysis of the SELECT2 trial, which evaluated EVT vs medical management (MM) in patients with large ischemic stroke, evaluated adults aged 18 to 85 years with acute ischemic stroke due to occlusion of the internal carotid or middle cerebral artery (M1 segment) as well as an Alberta Stroke Program Early CT Score (ASPECTS) of 3 to 5, core of 50 mL or greater on imaging, or both. Patients were enrolled between October 2019 and September 2022 from 31 EVT-capable centers in the US, Canada, Europe, Australia, and New Zealand. Data were analyzed from August 2023 to January 2024. EVT vs MM. Functional outcome, defined as modified Rankin Scale (mRS) score at 90 days with blinded adjudication. A total of 958 patients were screened and 606 patients were excluded. Of 352 enrolled patients, 145 (41.2%) were female, and the median (IQR) age was 66.5 (58-75) years. A total of 211 patients (59.9%) were transfers, while 141 (40.1%) presented directly. The median (IQR) transfer time was 178 (136-230) minutes. The median (IQR) ASPECTS decreased from the referring hospital (5 [4-7]) to an EVT-capable center (4 [3-5]). Thrombectomy treatment effect was observed in both directly presenting patients (adjusted generalized odds ratio [OR], 2.01; 95% CI, 1.42-2.86) and transferred patients (adjusted generalized OR, 1.50; 95% CI, 1.11-2.03) without heterogeneity (P for interaction = .14). Treatment effect point estimates favored EVT among 82 transferred patients with a referral hospital ASPECTS of 5 or less (44 received EVT; adjusted generalized OR, 1.52; 95% CI, 0.89-2.58). ASPECTS loss was associated with numerically worse EVT outcomes (adjusted generalized OR per 1-ASPECTS point loss, 0.89; 95% CI, 0.77-1.02). EVT treatment effect estimates were lower in patients with transfer times of 3 hours or more (adjusted generalized OR, 1.15; 95% CI, 0.73-1.80). Both directly presenting and transferred patients with large ischemic stroke in the SELECT2 trial benefited from EVT, including those with low ASPECTS at referring hospitals. However, the association of EVT with better functional outcomes was numerically better in patients presenting directly to EVT-capable centers. Prolonged transfer times and evolution of ischemic change were associated with worse EVT outcomes. These findings emphasize the need for rapid identification of patients suitable for transfer and expedited transport. ClinicalTrials.gov Identifier: NCT03876457.

Abstract TP203: Effect of SARS-CoV2 Infection on Endovascular Thrombectomy Outcomes - Data From the Florida Stroke Registry

Introduction: The outcomes of endovascular thrombectomy (EVT) in SARS-CoV2 positive patients with acute ischemic stroke (AIS) are not well studied. In the large Florida Stroke Registry we compared in hospital and discharge outcomes of patients with target vessel occlusions treated endovascularly with versus without a SARS-CoV2 positive infection status during their hospitalization. Methods: Data from Get With the Guidelines-Stroke hospitals participating in the Florida Stroke Registry from March 2020 to December 2022 were reviewed. EVT patients with coding for SARS-CoV2 testing during their hospital stay were categorized into SARS-CoV2 positive or negative groups. Associations between SARS-CoV2 status and favorable EVT outcomes of good mRS (0-2) at discharge, discharge to home or to rehabilitation centre, and independent ambulation at discharge were examined using multivariate logistic regression modeling adjusting for demographics, vascular risk factors, and clinical characteristics with generalized estimating equations (GEE). Temporal analyses compared outcomes across the years 2020-2022. Results: A total of 8,778 patients underwent EVT, of these, 193 (2.25%) were SARS-CoV2 positive. The odds of mRS 0-2 and independent ambulation at discharge were OR 0.194 (CI 0.035,1.077) and OR 0.794 (CI 0.168,3.75) in SARS-CoV2 positive relative to negative EVT patients. Outcomes of mRS 0-2 (OR 0.194, CI 0.035,1.077) and ambulation at discharge (OR 0.794, CI 0.168,3.75) were shy of statistical significance. Accounting for baseline differences SARS-CoV2 positive patients were less likely to be discharged home or to a rehabilitation centre (OR 0.671, CI 0.488,0.921) in multivariable analysis with GEE. Temporal analysis of SARS-CoV2 positive patients showed no significant differences across the years studied. Conclusions: In this large muliticentre stroke registry the results suggest that favorable outcomes post thrombectomy may be negatively impacted by SARS-CoV2 infection. Temporal assessment showed similar results across the years studied. These findings provide novel insight from a large database to add to the emerging literature examining outcomes of concurrent SARS-CoV2 infection in the setting of EVT for target vessel occlusion AIS.

Abstract 82: The Association of Transfer Status and Time on Clinical and Imaging Outcomes in Large Core Strokes: A SELECT2 Subanlaysis

Background: Patients with large core strokes have poor clinical outcomes and are frequently not transferred to endovascular thrombectomy (EVT)-capable centers for EVT. We analyzed the association of transfer status and time on neuroimaging changes, clinical outcomes and EVT treatment effect in SELECT2. Methods: Patients enrolled in the SELECT-2 trial were stratified based on transfer status. CT ASPECTS at outside hospital and EVT center were collected if available. Treatment effect was compared by transfer status as well as in transferred patients with outside ASPECTS ≤5. The association of ASPECTS loss during transfer was also quantified. The primary outcome was the distribution of modified Rankin Scale score at 90-day follow-up. Results: Of 352 enrolled patients, 211 (60%) were transferred to EVT capable center and 108(51%) received EVT. 141 presented directly and 72 (51%) received EVT. The median transfer time was 185 (140-234) minutes. Median ASPECTS decreased from outside hospital [5(4-7)] to EVT center [4 (3-5)] with ASPECTS decay rate at 0.31 (0-0.84) points/hour of transfer time, with 50/120 (42%) experienced ASPECTS loss ≥2. Thrombectomy treatment effect was preserved in both directly presenting patients [aGenOR: 2.01 (1.42-2.86)] as well as transferred patients [aGenOR: 1.50 (1.11-2.03)] without significant heterogeneity (P-int=0.14). EVT also demonstrated numerically better functional outcomes in transferred patients with outside ASPECTS of ≤5 (n=65, 35 EVT, aGenOR: 1.77 (0.97-3.23), p=0.068). ASPECTS loss was associated with worse clinical outcomes in EVT [aGenOR: 0.81 (0.71-0.83) per ASPECTS point loss] but not in MM: [aGenOR: 0.89 (0.73-1.08) per ASPECTS point loss]. Conclusion: In large core patients, transfer time was associated with ASPECTS decay, resulting in worse outcomes with EVT. Transferred patients however still benefited from EVT, with a trend towards better outcomes in patients with low ASPECTS at outside hospitals. These findings may substantially impact stroke care infrastructure, emphasizing the need for rapid identification of patients suitable for transfer and expedited transport. Clinicaltrials.gov registration: NCT03876457

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 60: Utilization, Workflow, and Outcomes of Endovascular Thrombectomy in Patients With versus Without Pre-Morbid Disability in a National Stroke Registry

Background: Given the paucity of high-quality data on acute stroke therapies in patients with pre-morbid disability, they risk being routinely excluded from such therapies. We examined utilization of endovascular thrombectomy (EVT), workflow, and outcomes among ischemic stroke patients with vs without pre-morbid disability in a national registry. Methods: We used data for the Czech Republic from 1-January-2016 to 31-December-2020. Pre-morbid disability was defined as pre-stroke modified Rankin Scale score (mRS) &gt;2. We compared receipt of EVT, workflow times, ΔmRS (change from pre-stroke to 3-months), intracerebral hemorrhage (ICH), mortality, and discharge NIHSS among patients with vs without pre-morbid disability, adjusting for age, sex, baseline NIHSS, and comorbidities, and verified using propensity score-weighting (PSW) for differences in treatment assignment. Results: Among 22,405 patients, 1,712 (7.6%) had pre-stroke mRS &gt;2. Patients with pre-morbid disability were less likely to receive EVT (10.1% vs 20.7%, aOR:0.30, 95%CI:0.24-0.36) and had longer door-to-puncture times (median:75-minutes, IQR:58-100 vs 54, IQR:27-77, adjusted-difference:12.5, 95%CI:2.68-22.3), worse ΔmRS (adjusted rate-ratio, aIRR on PSW:1.57, 1.43-1.72), rates of 3-month mRS 5-6, discharge NIHSS, and mortality (aOR-PSW[mortality]:2.54, 1.92-3.34); ICH rates did not differ. Among those with pre-morbid disability, 32.1% returned to pre-stroke state; this ranged from 19.6% for those &gt;85-years to 66.0% for &lt;65-years. EVT was associated with better outcomes including lower ΔmRS (aIRR-PSW:0.87, 0.83-0.91) and mortality, with no interaction of treatment effect by pre-morbid disability (e.g. mortality p interaction =0.73). EVT recipients with pre-morbid disability did not differ significantly for several key outcomes including ΔmRS (aIRR:0.99, 0.84-1.17), but were more likely to have mRS 5-6 (70.1% vs 39.5%, aOR:1.85, 1.12-3.04). Conclusions: Patients with pre-morbid disability were less likely to receive EVT and had slower treatment and worse outcomes than those without disability. However, patients fared better with EVT versus medical care, and one-third with pre-stroke disability returned to their pre-stroke state.

Abstract TP140: Effect of MR-Guided Perfusion Imaging Mismatch Profiles Within 6 Hours on Endovascular Thrombectomy Outcomes

Background: The treatment of acute ischemic stroke (AIS) aims to achieve early vascular recanalization and reperfusion of the penumbra. However, the effect of early penumbral imaging within 6 hours on clinical outcomes remains unclear. Objective: The objective of this study was to determine the effect of magnetic resonance-guided (MR-guided) perfusion imaging within 6 hours after symptom onset on endovascular thrombectomy outcomes in AIS patients. Methods: We prospectively collected the clinical information of consecutive AIS patients undergoing endovascular thrombectomy based on MR-guided perfusion imaging within 6 hours after symptom onset from AISRNA and EVTRNA studies. The primary outcome was defined as the poor outcome (mRS &gt; 2 within 90 days). The perfusion-weighted imaging/diffusion-weighted imaging (PWI/DWI) mismatch was assessed by an automated software. Results: We enrolled 84 patients (25 in the mismatch ≤ 1.8 group and 59 in the mismatch &gt; 1.8 group). Significant difference was found between the mismatch&gt;1.8 group and the mismatch≤1.8 group for the incidence of disabling stroke (mRS &gt; 2) within 90 days (40.7% vs. 68.0%, OR: 3.099, 95% CI: 1.154-8.323, P =0.025). Intracranial hemorrhage occurred in 8 patients (13.6%) in the mismatch &gt; 1.8 group and 10 patients in the mismatch ≤ 1.8 group (40.0%) (P = 0.010). The risk of severe cerebral edema was 2/59 (3.4%) vs. 7/25 (28.0%) (P = 0.004). These findings remained stable after adjustment. Conclusion: MR-guided perfusion imaging mismatch profiles within 6 hours after symptom onset may be feasible to improve clinical outcomes and reduce clinically ineffective reperfusion after endovascular thrombectomy.

Abstract TP200: Anticoagulation Use and Endovascular Thrombectomy in Patients With Large Core Stroke - A Secondary Analysis of SELECT2 Trial

Introduction: Anticoagulation (AC) use is common in patients presenting with acute ischemic stroke and is known to pose challenges to acute reperfusion therapy. However, evidence about association of AC use prior to stroke with endovascular thrombectomy outcomes and post-procedure hemorrhages, especially in those with large strokes is limited. Methods: From SELECT2, patients were stratified based on AC medication use and prior to stroke. Functional outcomes at 90day follow-up and hemorrhagic transformation on follow-up imaging were compared between patients with and without AC in adjusted regression models. Results: Of 352 patients, 29/180 (16%, VKA - 15, DOACs 14) EVT patients and 18/172 (10%, VKA - 3, DOACs 15) MM patients were receiving anticoagulants at baseline. AC patients were older (72 (62-79) y vs 66 (58-75) y), with higher cardiac morbidity (Congestive Heart Failure: 28% vs 10%, Atrial Fibrillation: 70% vs 17%), but had similar NIHSS [20 (16-24) vs 18 (15-23)], time to randomization [511 (350-909) vs 586 (326-920) minutes], CT ASPECTS [4 (3-5) vs 4 (3-5)] and ischemic core estimates [91 (71 -110) vs 103 (71-139) ml, AC vs nonAC respectively]. Within AC patients, EVT did not improve outcomes (Shift: 6 (4-6) vs 5 (4-6), aGenOR: 0.89 (0.53-1.50), mRS 0-3: 11% vs 14%, aRR: 1.27 (0.40-4.05), mRS 5-6: 69% vs 67%, aRR: 1.05 (0.73-1.50)]. Furthermore, EVT patients on AC reported numerically higher rates of any intracerebral hemorrhage [85.7% vs 70.2%, aRR: 1.18, 95% CI: 0.98-1.43], but no sICH or parenchymal hemorrhage and demonstrated worse outcome [median mRS: 6 (4-6) vs 4 (3-6), aGenOR: 0.49(0.32-0.74)], mRS 0-3: 14% vs 43%, aRR: 0.36 (0.15-0.86)], and mRS 5-6: 69% vs 43%, aRR: at 90 day follow-up and numerically lower functional independence (mRS 0-2) [3.4% vs 23.3%, aRR: 0.18(0.03-1.21)], AC vs nonAC respectively. Consistent results were observed in patients achieving successful reperfusion. Conclusion: Almost 1/7 th of patients presenting with large stroke in SELECT2 trial demonstrated AC use at baseline, with higher cardiac morbidity. These patients were more likely to have hemorrhagic outcomes and worse clinical outcomes after EVT and successful reperfusion. Clinicaltrials.gov registration: NCT03876457

Abstract 156: Cerebral Edema in Patients Presenting With Large Ischemic Core Undergoing Thrombectomy versus Medical Therapy: Secondary Analysis of SELECT 2 Trial

Background: Endovascular thrombectomy (EVT) improves long-term outcome in patients presenting with large ischemic core but is associated with early neurological worsening (ENW), potentially related to cerebral edema post-reperfusion. We investigated whether EVT increases edema development, and the relationship between edema and ENW in a secondary analysis of the SELECT2 trial. Methods: SELECT 2 tested the efficacy and safety of EVT versus medical therapy in patients with large ischemic core (ASPECTS 3-5 or core volume ≥50ml on CT Perfusion[CTP]/MR diffusion). Core volume was defined as the larger of the CTP-CBF relative cerebral blood flow &lt;30% or the visible hypodensity on non-contrast CT. Cerebral edema was measured as the maximum midline shift (MLS) on 24h follow-up MRI or CT. ENW was defined as &gt;=4 point worsening in NIHSS at 24h compared to baseline. Probabilistic index model was used in multivariable analyses to assess ≥1 point improvement on modified Rankin Scale at 90-days. Results: After exclusion of 10 patients with hemicraniectomy, the median MLS in 327 patients was 2.75mm (IQR 0-5.85) in EVT and 0mm (IQR 0-4.02) in control patients (p=0.005). EVT was independently associated with greater MLS (adjusted odds ratio, aOR 1.50, 95%CI 1.17-1.92, p=0.0012) after adjusting for age and core volume. There was no interaction between EVT and core volume on the association with MLS (p&gt;0.79). Patient with ENW had greater MLS (5.05mm [IQR2.06-10.2] vs 0mm [IQR0-3.94, p&lt;0.001]) MLS was associated with development of ENW (aOR 1.22, 95%CI 1.13-1.32, p&lt;0.001), and lower likelihood of long-term functional improvement (adjusted generalized OR 0.96, 95%CI 0.92-0.97, p&lt;0.001, adjusted for core volume, EVT, age and baseline NIHSS). Sensitivity analysis testing alternative definitions of core volume (CTP core volume only and Hypodensity on non-contrast only) showed concordant results. Conclusion: In patients presenting with large ischemic core, EVT was associated with increased cerebral edema at 24h which, in turn, was associated with ENW. Despite overall benefit of EVT, EVT-related edema is independently associated with neurological deterioration and long-term disability and is therefore a potential treatment target to improve EVT outcomes.

Abstract 232: Endovascular Thrombectomy for Distal Vessel Occlusions in Early vs Extended Time Window

Introduction There has been a growing body of literature in recent years suggesting the safety and efficacy of endovascular thrombectomy (EVT) in patients with acute ischemic stroke (AIS) from distal vessel occlusion (DVO). Limited data is available regarding the risks and benefits of EVT in this patient population, especially when comparing the early window (6 hours from LKW) to the extended window (6‐24 hours from LKW). We aim to study this further. Methods We queried our stroke registry, a prospectively maintained database of AIS patients who presented from December 2014 to July 2023, and isolated patients with DVO who underwent EVT. DVO was defined as M2, M3, M4 occlusion, ACA occlusion, and/or PCA occlusion. We then further subdivided this into two groups, patients within the early window, and patients within the extended window. We compared characteristics between these groups using univariate analysis. We additionally performed a multivariable logistic regression analysis adjusted for Alberta Stroke Program Early CT Score (ASPECTS), National Institutes of Health Stroke Scale (NIHSS) score, age, sex, and use of intravenous (IV) thrombolysis to investigate whether or not extended window thrombectomy was associated with worse outcome. Our primary outcomes were modified Rankin Score (mRS) at discharge and at 90 days. Results Total of 290 patients had DVO and underwent EVT. Of these, 214 had all relevant data. 147 (68.7%) underwent EVT in the early window and 67 (31.3%) received EVT in the extended window. Mean age was 72.3 (±14.4). There were more women in the extended window 51.5% vs 44.8% (χ² = 20.57, p‐value &lt; 0.001). No significant difference was observed in the average NIHSS between early (13.7) and extended (13.9) windows (t=‐0.44, p=0.66). Similarly, the median ASPECTS score was comparable between early (9.3) and extended (9.0) windows (t=1.41, p=0.16). As expected, there was a striking difference seen in patients receiving IV thrombolysis between early (54.5%) and extended (4.5%) windows (χ²=48.48, p&lt;0.001). Post‐operative hematoma also was not different between the early (23.8%) and extended (14.9%) windows (χ² = 0.69, p‐value = 0.40). Symptomatic intracerebral hemorrhage (SICH) was only seen in 3.4% of patient in the early window and 2.9% of patients in extended window. No significant difference was found in the mRS at discharge (early: 3.1, extended: 3.4, t=‐0.90, p=0.37) or at 90 days (early: 3.1, extended: 3.5, t=‐1.08, p=0.29). Additionally, in our multivariable logistic regression model, receiving EVT in the extended window didn't significantly affect the discharge mRS (β=0.10, p=0.27) or the 90 day mRS (β=‐0.15, p=0.38). In this model, increasing age, lower ASPECTS score, and higher admission NIHSS predicted a higher discharge mRS, while IV thrombolysis was linked to a lower discharge mRS. Higher admission NIHSS was associated with a higher mRS at both discharge and 90 days. Conclusion In our study, outcome of EVT in the extended time window in patients with DVO was comparable to EVT outcome in early window, with no increased hemorrhagic complications. More studies are required to further understand the risks and benefits of EVT in patients with DVO stroke

Abstract 194: Impact of Pre‐treatment Cerebral Microbleeds on the Outcomes of Endovascular Thrombectomy

Introduction Endovascular thrombectomy (EVT) is the gold standard treatment for patients with acute ischemic stroke (AIS) caused by large vessel occlusion (LVO), and there are several factors that can influence the outcomes of EVT in AIS‐LVO patients. We conducted this meta‐analysis to investigate the effect of cerebral microbleeds (CMBs) on the functional and safety outcomes of EVT in patients with AIS caused by LVO. Methods We followed the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) guidelines. We included observational studies that recruited AIS‐LVO patients, used susceptibility‐sensitive magnetic resonance imaging (MRI) to detect CMBs, and examined the association between them and predefined outcome events. The outcomes of interest included functional independence, revascularization success, and hemorrhagic adverse events. We conducted a meta‐analysis using the Mantel‐Haenszel method and calculated the risk ratios. Results Four studies involving 1,514 patients were included. A significant reduction in the likelihood of achieving a favorable functional outcome, as measured by the modified Rankin Scale (mRS), was observed in patients with CMBs (Risk Ratio (RR) 0.70, 95% Confidence Interval (CI): 0.53 ‐ 0.91, P=0.01). No significant differences were observed between the two groups in terms of successful revascularization (RR 0.93, 95% CI [0.74 to 1.17], P=0.51), mortality (RR 0.93, 95% CI [0.74 to 1.17], P=0.51), hemorrhagic transformation (RR 0.93, 95% CI [0.59 to 1.45], P=0.74), and parenchymal hematoma (RR 1.23, 95% CI [0.79 to 1.91], P=0.35). Conclusion The presence of CMBs significantly reduced the likelihood of achieving a favorable functional outcome after EVT in AIS‐LVO patients. However, CMBs did not impact the rates of successful revascularization, mortality, or the occurrence of various hemorrhagic complications. Future research should explore the mechanisms of this association and strategies to mitigate its impact.