Occlusion Acute Ischemic Stroke Research Articles

Endovascular thrombectomy versus intravenous thrombolysis for primary distal, medium vessel occlusion in acute ischemic stroke

Abstract Introduction In the absence of clinical trials, the benefit of endovascular therapy (EVT) on the treatment of acute ischemic stroke (AIS) with primary distal and medium vessel occlusions (DMVO) is still not well defined. The aim of the study is to evaluate EVT with or without intravenous thrombolysis (EVT ± IVT) in primary DMVO stroke in comparison with a control cohort treated with IVT alone. Methods We analysed all consecutive AIS with proven primary DMVO. Primary endpoints were excellent outcome, functional independence at 3 months follow-up, and early neurologic improvement at 1 day after treatment. Results One hundred and fourteen patients with DMVO strokes were included between 2019 and 2023. Propensity-weighted analysis showed no significant differences in EVT ± IVT vs IVT for the excellent outcome (adjusted OR [aOR], 1.575; 95% CI, 0.706–3.513), functional independence (aOR, 2.024; 95% CI, 0.845–4.848), early neurological improvement (aOR, 2.218; 95% CI, 0.937–5.247), mortality (aOR, 0.498; 95% CI, 0.177–1.406), symptomatic intracranial haemorrhage (aOR, 0.493; 95% CI, 0.102–2.385), and subarachnoid haemorrhage (aOR, 0.560; 95% CI, 0.143–2.187). The type of revascularization did not influence the percentage of cerebral volume lost (adjusted linear regression estimate, −19.171, t value, 11.562; p = 0.104). Conclusions This study supports the hypothesis that patients with primary DMVO stroke treated with EVT (±IVT) or IVT alone have comparable outcomes.

Leukocyte counts and ratios as potential predictors of large vessel occlusion in acute ischemic stroke: A retrospective cohort study.

Leukocyte counts and ratios are independent biomarkers to determine the severity and prognosis of acute ischemic stroke (AIS). In AIS, the connection between leukocytes and large vessel occlusion (LVO) is uncertain. This study aims to determine the relationship between the existence of LVO and leukocyte counts and ratios on admission to AIS. Patients were retrospectively evaluated within six hours of AIS starting between January 2019 and April 2023. On admission, blood specimens were collected, and leukocyte subtype counts were promptly analyzed. Computed tomography or digital subtraction angiography were utilized to verify the existence of LVO. Regression analysis and receiver operating characteristic (ROC) curves were employed to investigate the connections between the counts and ratios of leukocytes and the existence of LVO, as well as the discriminatory ability of these variables in predicting LVO. Total white blood cell (WBC) count, neutrophil count, and neutrophil-to-lymphocyte ratio (NLR) were substantially higher in the LVO existence group compared to the LVO absence group, whereas the ratio of eosinophils to neutrophils (ENR × 102) was lower (P < .001, respectively). Significant associations were observed between total WBC counts, neutrophil counts, NLR, and ENR × 102 and the existence of LVO (P < .001, respectively). Total WBC counts, neutrophil counts, NLR, and ENR × 102 had respective areas under the curves (AUC) of 0.730, 0.748, 0.704, and 0.680 for identifying LVO. Our results show that in AIS patients, the existence of LVO is independently associated with elevated total WBC and neutrophil counts, high NLR, and low ENR × 102 levels. Neutrophil and total WBC counts, as well as NLR and levels of ENR × 102, may serve as potential biomarkers for predicting LVO. Neuroinflammation, based on the existence of LVO, should be given particular attention in future investigations.

Hyperglycemia Is Associated With Computed Tomography Perfusion Core Volume Underestimation in Patients With Acute Ischemic Stroke With Large‐Vessel Occlusion

BACKGROUND Computed tomography perfusion (CTP) predictions of infarct core play an important role in the determination of treatment eligibility in large‐vessel occlusion acute ischemic stroke. Prior studies have demonstrated that blood glucose can affect cerebral blood flow. Here, we examine the influence of acute and chronic hyperglycemia on CTP estimations of infarct core. METHODS From our prospectively collected multicenter observational cohort, we identified patients with large‐vessel occlusion acute ischemic stroke who underwent CTP with RAPID (IschemaView, Stanford, CA) postprocessing, followed by endovascular therapy with substantial reperfusion (Thrombolysis in Cerebral Infarction 2b–3) within 90 minutes, and final infarct volume determination by magnetic resonance imaging 48 to 72 hours posttreatment. Core volume overestimations and underestimations were defined as a difference of at least 20 mL between CTP‐RAPID predicted infarct core and Diffusion Weighted Imaging (DWI) final infarct volume. Primary outcome was the association of presentation glucose and hemoglobin A1c (HgbA1c) with underestimation of core volume and was measured using multivariable logistic regression adjusted for comorbidities and presentation characteristics. Secondary outcomes included frequency of overestimation of infarct core. RESULTS Among 256 patients meeting inclusion criteria, median age was 67 (interquartile range [IQR], 57–77) years, 51.6% were women, and 132 (51.6%) and 93 (36.3%) had elevated presentation glucose and elevated HgbA1c, respectively. Median CTP‐predicted core was 6 mL (IQR, 0–30 mL), median DWI final infarct volume was 14 mL (IQR, 6‐43 mL), and median difference was 12 mL (IQR, 5–35 mL). Twenty‐eight (10.9%) patients had infarct core overestimation and 68 (26.6%) had underestimation. Compared with those with no underestimation, patients with underestimation had elevated blood glucose (median, 119 [IQR, 103–155] versus 138 [IQR, 117–195] mg/dL; P = 0.002) and HgbA1c (median, 5.80% [IQR, 5.40–6.40] versus 6.40% [IQR, 5.50–7.90]; P = 0.009). In multivariable analysis, underestimation was independently associated with elevated glucose (adjusted odds ratio [OR], 2.10; P = 0.038) and HgbA1c (adjusted OR, 2.37; P = 0.012). Overestimation was associated with lower presentation blood glucose (median, 109 [IQR, 99–132] in overestimation versus 127 [IQR, 107–172] mg/dL in no overestimation; P = 0.003) and HgbA1c (5.6%[IQR 5.1–6.2] in overestimation versus 5.90%[IQR, 5.50–6.70] in no overestimation; P = 0.012). CONCLUSIONS Acute and chronic hyperglycemia were strongly associated with CTP underestimation in patients with large‐vessel occlusion acute ischemic stroke undergoing endovascular therapy. Glycemic state should be considered when interpreting CTP findings in patients with large‐vessel occlusion acute ischemic stroke.

Deep learning-assisted diagnosis of large vessel occlusion in acute ischemic stroke based on four-dimensional computed tomography angiography.

To develop deep learning models based on four-dimensional computed tomography angiography (4D-CTA) images for automatic detection of large vessel occlusion (LVO) in the anterior circulation that cause acute ischemic stroke. This retrospective study included 104 LVO patients and 105 non-LVO patients for deep learning models development. Another 30 LVO patients and 31 non-LVO patients formed the time-independent validation set. Four phases of 4D-CTA (arterial phase P1, arterial-venous phase P2, venous phase P3 and late venous phase P4) were arranged and combined and two input methods was used: combined input and superimposed input. Totally 26 models were constructed using a modified HRNet network. Assessment metrics included the areas under the curve (AUC), accuracy, sensitivity, specificity and F1 score. Kappa analysis was performed to assess inter-rater agreement between the best model and radiologists of different seniority. The P1 + P2 model (combined input) had the best diagnostic performance. In the internal validation set, the AUC was 0.975 (95%CI: 0.878-0.999), accuracy was 0.911, sensitivity was 0.889, specificity was 0.944, and the F1 score was 0.909. In the time-independent validation set, the model demonstrated consistently high performance with an AUC of 0.942 (95%CI: 0.851-0.986), accuracy of 0.902, sensitivity of 0.867, specificity of 0.935, and an F1 score of 0.901. The best model showed strong consistency with the diagnostic efficacy of three radiologists of different seniority (k = 0.84, 0.80, 0.70, respectively). The deep learning model, using combined arterial and arterial-venous phase, was highly effective in detecting LVO, alerting radiologists to speed up the diagnosis.

The Importance of Increased Serum GFAP and UCH-L1 Levels in Distinguishing Large Vessel from Small Vessel Occlusion in Acute Ischemic Stroke.

Acute ischemic stroke (AIS) is one of the leading causes of morbidity worldwide, thus, early recognition is essential to accelerate treatment. The only definite way to diagnose AIS is radiological imaging, which is limited to hospitals. However, two serum neuromarkers, glial fibrillary acidic protein (GFAP) and ubiquitin C-terminal hydrolase-L1 (UCH-L1), have been proven as indicators of brain trauma and AIS. We aimed to investigate the potential utility of these markers in distinguishing between large vessel occlusion (LVO) and small vessel occlusion (SVO), considering differences in treatment. Sixty-nine AIS patients were included in our study and divided into LVO and SVO groups based on radiological imaging. Control group consisted of 22 participants without history of neurological disorders. Results showed differences in serum levels of both GFAP and UHC-L1 between all groups; control vs. SVO vs. LVO (GFAP: 30.19 pg/mL vs. 58.6 pg/mL vs. 321.3 pg/mL; UCH-L1: 117.7 pg/mL vs. 251.8 pg/mL vs. 573.1 pg/mL; p < 0.0001), with LVO having the highest values. Other prognostic factors of stroke severity were analyzed and did not correlate with serum biomarkers. In conclusion, a combination of GFAP and UCH-L1 could potentially be a valuable diagnostic tool for differentiating LVO and SVO in AIS patients.

What Is a Meaningful Difference When Using Infarct Volume as the Primary Outcome?: Results From the HERMES Database.

Ischemic stroke lesion volume at follow-up is an important surrogate outcome for acute stroke trials. We aimed to assess which differences in 48-hour lesion volume translate into meaningful clinical differences. We used pooled data from 7 trials investigating the efficacy of endovascular treatment for anterior circulation large vessel occlusion in acute ischemic stroke. We assessed 48-hour lesion volume follow-up computed tomography or magnetic resonance imaging. The primary outcome was a good functional outcome, defined as modified Rankin Scale (mRS) scores of 0 to 2. We performed multivariable logistic regression to predict the probability of achieving mRS scores of 0 to 2 and determined the differences in 48-hour lesion volume that correspond to a change of 1%, 5%, and 10% in the adjusted probability of achieving mRS scores of 0 to 2. In total, 1665/1766 (94.2%) patients (median age, 68 [interquartile range, 57-76] years, 781 [46.9%] female) had information on follow-up ischemic lesion volume. Computed tomography was used for follow-up imaging in 83% of patients. The median 48-hour lesion volume was 41 (interquartile range, 14-120) mL. We observed a linear relationship between 48-hour lesion volume and mRS scores of 0 to 2 for adjusted probabilities between 65% and 20%/volumes <80 mL, although the curve sloped off for lower mRS scores of 0-2 probabilities/higher volumes. The median differences in 48-hour lesion volume associated with a 1%, 5%, and 10% increase in the probability of mRS scores of 0 to 2 for volumes <80 mL were 2 (interquartile range, 2-3), 10 (9-11), and 20 (18-23) mL, respectively. We found comparable associations when assessing computed tomography and magnetic resonance imaging separately. A difference of 2, 10, and 20 mL in 48-hour lesion volume, respectively, is associated with a 1%, 5%, and 10% absolute increase in the probability of achieving good functional outcome. These results can inform the design of future stroke trials that use 48-hour lesion volume as the primary outcome.

Use of the SONAS Ultrasound Device for the Assessment of Cerebral Perfusion in Acute Ischemic Stroke

Background Early recognition of large‐vessel occlusion in acute ischemic stroke is pivotal to ensuring timely and effective treatment. However, current prehospital evaluation strategies largely rely on stroke scales that lack sensitivity and specificity. Recently, a novel, portable, noninvasive brain perfusion ultrasound device (SONAS) was developed as a diagnostic aid and demonstrated robust correlation with magnetic resonance imaging–based brain perfusion imaging. The present study aimed to investigate the feasibility and diagnostic performance of the SONAS device in identifying alterations in cerebral blood flow in patients with acute ischemic stroke with suspected or known perfusion deficits. Methods We performed a phase II, single‐arm, prospective study using SONAS in a close timely relation to computed tomography perfusion imaging in subjects diagnosed with acute ischemic stroke and suspected or known large‐vessel pathology, presenting within 24 hours of symptom onset between April 2019 through December 2019. Performance end points included successful measurement of time‐to‐peak in each hemisphere and comparison of perfusion deficits measured by SONAS to the reference standard computed tomography perfusion imaging. Safety end points included frequency, severity, and outcome of adverse events. Results A total of 20 subjects were enrolled. Eighteen subjects (90%) had microbubble signals successfully detected on initial assessment by SONAS. The diagnostic accuracy of the SONAS device in identifying a perfusion deficit was 88.9%. The sensitivity was 14 of 15 (93.3%), and the specificity was 2 of 3 (66.7%). No adverse events were reported secondary to SONAS or the contrast agent used. Conclusion In this clinical study, we demonstrated that the SONAS system is a safe tool that can aid in identifying cerebral perfusion deficits in this selected population of patients with acute ischemic stroke with suspected or known perfusion deficits. Future studies should assess the efficacy and impact on clinical outcomes of using SONAS in a real‐world “in the field” setting on a large subset of patients with suspected stroke and in addition to prehospital stroke scales.

Incidence and clinical outcomes of perforations during mechanical thrombectomy for medium vessel occlusion in acute ischemic stroke: A retrospective, multicenter, and multinational study.

Mechanical thrombectomy (MT) has revolutionized the treatment of acute ischemic stroke (AIS) due to large vessel occlusion (LVO), but its efficacy and safety in medium vessel occlusion (MeVO) remain less explored. This multicenter, retrospective study aims to investigate the incidence and clinical outcomes of vessel perforations (confirmed by extravasation during an angiographic series) during MT for AIS caused by MeVO. Data were collected from 37 academic centers across North America, Asia, and Europe between September 2017 and July 2021. A total of 1373 AIS patients with MeVO underwent MT. Baseline characteristics, procedural details, and clinical outcomes were analyzed. The incidence of vessel perforation was 4.8% (66/1373). Notably, our analysis indicates variations in perforation rates across different arterial segments: 8.9% in M3 segments, 4.3% in M2 segments, and 8.3% in A2 segments (p = 0.612). Patients with perforation had significantly worse outcomes, with lower rates of favorable angiographic outcomes (TICI 2c-3: 23% vs 58.9%, p < 0.001; TICI 2b-3: 56.5% vs 88.3%, p < 0.001). Functional outcomes were also worse in the perforation group (mRS 0-1 at 3 months: 22.7% vs 36.6%, p = 0.031; mRS 0-2 at 3 months: 28.8% vs 53.9%, p < 0.001). Mortality was higher in the perforation group (30.3% vs 16.8%, p = 0.008). This study reveals that while the occurrence of vessel perforation in MT for AIS due to MeVO is relatively rare, it is associated with poor functional outcomes and higher mortality. The findings highlight the need for increased caution and specialized training in performing MT for MeVO. Further prospective research is required for risk mitigation strategies.

Safety and Efficacy of Low-Dose Eptifibatide for Tandem Occlusions in Acute Ischemic Stroke.

The optimal treatment strategy for ischemic stroke in patients presenting with tandem occlusions of the internal carotid artery remains controversial. Several studies have demonstrated better clinical outcomes after eptifibatide, which is a short half-life antiplatelet agent. This retrospective analysis focused on the safety and efficacy of low-dose eptifibatide administration in stroke patients with tandem lesions. We evaluated the results of endovascular treatment in 148 stroke patients with tandem lesions. Patients in whom balloon angioplasty alone resulted in satisfactory cerebral flow did not receive eptifibatide (33 patients); others received this drug together with stent implantation (115 patients). Eptifibatide was given as an intravenous bolus of 180 μg/kg and then in a modified low dose of 1 μg/kg/min for 24 hours. There were no statistically significant differences between both groups regarding 30-day mortality, frequency of thrombotic events, or hemorrhagic complications. An analysis of clinical status at 30-day follow-up revealed that the administration of eptifibatide was associated with a statistically significant better outcome: a higher rate of either no neurological symptoms or only mild symptoms (4 NIHSS points maximally). The administration of eptifibatide in stroke patients presenting with tandem lesions is relatively safe. Moreover, treatment with this drug can improve clinical outcomes in these challenging patients.

Variation in Vessel Size and Angiographic Outcomes Following Stent‐Retriever Thrombectomy in Acute Ischemic Stroke: STRATIS Registry

Background Mechanical thrombectomy is established for large‐vessel occlusions in acute ischemic stroke, but the potential role in distal vessel occlusions of medium arteries is less well established. Such medium or distal arterial segments have not been assessed with respect to thrombectomy devices used during endovascular therapy. We conducted an analysis of arterial size, segmental anatomy, and stent‐retriever device performance with respect to vessel size during thrombectomy. Methods The STRATIS registry angiography core laboratory adjudicated the exact location of the occlusion, proximal, and distal device deployment, relationship to arterial bifurcations, and anatomic nomenclature. Arterial diameters were measured at all these sites. Statistical analyses examined the relationship between vessel and stent size, and arterial recanalization using expanded Thrombolysis in Cerebral Infarction reperfusion score. Results Overall, 665 patients with stroke were included following thrombectomy using various Solitaire device sizes, including Solitaire 4×40, Solitaire 6×30, Solitaire 4×20, Solitaire 6×20, and Solitaire 4×15. Arterial diameter at the occlusion site was a median of 2.17 mm (interquartile range [IQR], 1.88–2.60 mm) in the distal M1, 1.67 mm (IQR, 1.47–2.06 mm) in the proximal M2 middle cerebral artery, 1.50 mm (IQR, 1.15–1.61 mm) in the distal M2 middle cerebral artery, 1.24 mm (IQR, 1.11–1.24 mm) in the M3 middle cerebral artery, and 1.88 mm (IQR, 1.49–1.94 mm) in the P1 posterior cerebral artery. Expanded Thrombolysis in Cerebral Infarction 2b to 3 reperfusion was achieved in all M3 or P1 segment occlusions. The rate of first‐pass recanalization was significantly higher in patients with medium (0.75–2 mm) versus large (&gt;2 mm) vessel occlusion (69.5% versus 57.1%; P = 0.003). Conclusion Considerable overlap was noted between arterial sizes at occlusion sites carrying different segmental arterial nomenclature or vessel names. Substantial reperfusion may be achieved with currently available mechanical thrombectomy devices in medium arteries.

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.

Mechanical thrombectomy in low Alberta stroke program early CT score (ASPECTS) in hyperacute stroke-a systematic review and meta-analysis.

Major randomized controlled trials of mechanical thrombectomy (MT) for acute ischemic stroke (AIS) failed to include a substantial number of patients presenting with low baseline Alberta Stroke Program Early CT Score (ASPECTS:0-5). Patients experiencing hyperacute strokes (last known well ≤ 6 h) can potentially benefit most from MT. We conducted a systematic review and meta-analysis to report presentation severity and radiographic and clinical outcomes for hyperacute stroke patients presenting with low-ASPECTS. Our comprehensive literature search of PubMed, Embase, and Cochrane databases up to August 31, 2022 included articles reporting patients presenting hyperacutely who underwent MT for anterior circulation large vessel occlusion AIS with an ASPECTS ≤ 5 on baseline imaging. Pooled averages were calculated for age and presenting National Institutes of Health Stroke Scale (NIHSS). Fixed- and random-effects meta-analyses for weighted estimation of overall rates were performed. Forest plots were generated for proportions and estimated overall outcome rates. 18 studies (1958 patients) were included (mean age = 64.1 years; presenting NIHSS = 18.4). Final modified thrombolysis in cerebral infarction 2b-3 grade was achieved in 76.4%, with symptomatic intracranial hemorrhage in 12.1%. Good (modified Rankin Scale [mRS] 0-2) and ambulatory (mRS 0-3) 3-month outcomes were achieved by 27.4 and 46.7%, respectively; 90-day mortality was 26.4%. MT in low-ASPECTS hyperacute stroke patients may result in ambulatory clinical outcomes with acceptable hemorrhage risk. Recanalization rates achieved were similar to those in patients presenting with ASPECTS ≥ 6; this did not fully translate to better clinical outcomes. MT should be considered for hyperacute strokes with low presenting ASPECTS.

Diagnosis and management of tandem occlusion in acute ischemic stroke

Approximately 20–30% of patients with acute ischemic stroke, caused by large intracranial vessel occlusion, have a tandem lesion, defined as simultaneous presence of high-grade stenosis or occlusion of the cervical internal carotid artery and thromboembolic occlusion of the intracranial terminal internal carotid artery or its branches, usually the middle cerebral artery. Patients with tandem lesions have usually worse outcomes than patients with single intracranial occlusions, and intravenous thrombolysis is less effective in these patients. Although endovascular thrombectomy is currently a cornerstone therapy in the management of acute ischemic stroke due to large vessel occlusion, the optimal management of extracranial carotid lesions in tandem occlusion remains controversial. Acute placement of a stent in the cervical carotid artery lesion is the most used therapeutic strategy compared with stented balloon angioplasty and thrombectomy alone without carotid artery revascularization; however, treatment strategies in these patients are often more complex than with single occlusion, so treatment decisions can change based on clinical and technical considerations. The aim of this review is to analyze the results of different studies and trials, investigating the periprocedural neurointerventional management of patients with tandem lesions and the safety, efficacy of the different technical strategies available as well as their impact on the clinical outcome in these patients, to strengthen current recommendations and thus optimize patient care.

Medical Management Versus Endovascular Treatment for Large-Vessel Occlusion Anterior Circulation Stroke With Low NIHSS.

Endovascular treatment (EVT) for acute ischemic stroke (AIS) patients presenting with National Institutes of Health Stroke Scale score of 0 to 5 is common in clinical practice but has not yet been proven safe and effective. Our objective is to assess whether EVT on top of best medical treatment (BMT) in AIS patients with large-vessel occlusion of the anterior circulation presenting with mild symptoms is beneficial compared with BMT. We searched MEDLINE, SCOPUS, and reference lists of retrieved articles published until December 28, 2022. A systematic literature search was conducted to identify clinical trials or observational cohort studies evaluating patients with AIS due to anterior circulation large-vessel occlusion and admission National Institutes of Health Stroke Scale score ≤5 treated with EVT versus BMT alone. The primary outcome was excellent functional outcome (modified Rankin Scale score 0-1) at 3 months. The protocol had been registered before data collection (PROSPERO). Eleven observational eligible studies were included in the meta-analysis, comprising a total of 2019 AIS patients with National Institutes of Health Stroke Scale score ≤5 treated with EVT versus 3171 patients treated with BMT. EVT was not associated with excellent functional outcome (risk ratio, 1.10 [95% CI, 0.93-1.31]). When stratified for different study design (per-protocol versus intention-to-treat), there were no significant subgroup differences. EVT was not associated with good functional outcome (modified Rankin Scale score 0-2; risk ratio, 1.01 [95% CI, 0.89-1.16]) or reduced disability at 3 months (common odds ratio, 0.92 [95% CI, 0.60-1.41]). Symptomatic intracranial hemorrhage was more common in the patients receiving EVT (risk ratio, 3.53 [95% CI, 2.35-5.31]). No correlation was found between EVT and mortality at 3 months (risk ratio, 1.34 [95% CI, 0.83-2.18]). The same overall associations were confirmed in the sensitivity analysis of studies that performed propensity score matching. EVT appears equivalent to BMT for patients with anterior circulation large-vessel occlusion AIS with low baseline National Institutes of Health Stroke Scale, despite the increased risk for symptomatic intracranial hemorrhage. URL: https://www.crd.york.ac.uk/PROSPERO/; Unique identifier: CRD42022334417.

E.2 Predictors of successful endovascular thrombectomy for M2 occlusion in acute ischemic stroke

Background: There remains lack of data in regards to factors influencing successful endovascular reperfusion of isolated occlusion of the M2 segment of the middle cerebral artery (MCA). In this study, we set out to investigate the variables that affect the successful endovascular reperfusion of isolated M2 segment occlusion. Methods: M2 segment occlusion was defined as isolated clot anywhere within the M2 segment of the MCA. A prediction model of successful endovascular reperfusion defined as modified Thrombolysis in Cerebral Ischemia (mTICI) score of 2b, 2c and 3 and unsuccessful endovascular reperfusion defined as mTICI score of 0, 1 and 2a was developed from demographics (age, sex) , clinical factors (NIHSS at the time of presentation to hospital), imaging characteristics (ASPECTS, ICA occlusion, presence of Intracranial arterial disease (ICAD), computed tomography perfusion (CTP)-based ischemic core and mismatch volume estimation), and treatment (alteplase/tenecteplase use and periprocedural complications) variables from 64 patients who underwent endovascular thrombectomy (EVT) at Kingston Health Science Centre between December 24, 2018 and October 18, 2022. Results: The only statistical significant predictor of successful endovascular reperfusion was CTP-based ischemic core volume (smaller core volume) (p&lt;0.05). Conclusions: The CTP-based ischemic core volume is the most important predictor of successful endovascular reperfusion for M2 occlusion.

Comparison Between In‐Hospital and Community‐Onset Stroke Treated With Endovascular Thrombectomy: A Propensity Score–Matched Cohort Study

Background Patients with acute ischemic stroke onset during hospital admission often have concurrent illnesses, increased underlying comorbidities and are often associated with a delayed recognition of stroke onset, compared with patients with stroke onset in the community (community‐onset stroke [COS]). Endovascular thrombectomy (EVT) for large‐vessel occlusion in acute ischemic stroke has been proven to be effective, though the safety and feasibility of EVT among patients with in‐hospital stroke (IHS) onset remains undetermined. We aim to compare the workflow and clinical outcomes for patients undergoing EVT following IHS onset and COS. Methods Using data from a national stroke registry, we used propensity score‐matched individual‐level data of patients who underwent EVT, following IHS and COS, between October 2015 and March 2020. Univariate analysis was performed to assess the procedural, functional, and safety outcomes. Results We included 4353 patients (COS, 4104 [249 after propensity score matching]; IHS, 249 [249 after propensity score matching]). Compared with COS, patients with IHS had similar modified Rankin Scale on discharge (odds ratio [OR], 0.98 [95% CI, 0.72–1.34]; P =0.96) and at 6 months (OR, 1.25 [95% CI, 0.71–2.24]; P =0.48). No significant difference in achieving good functional outcome (modified Rankin Scale ≤ 2 at discharge; 31.3% [IHS] versus 29.3% [COS]; OR,=1.10 [95% CI 0.74–1.60]; P =0.61), successful reperfusion (modified Thrombolysis in Cerebral Infarction score of 2b–3), P =0.82; or safety outcomes of symptomatic intracranial hemorrhage ( P =0.64) and in‐hospital mortality ( P =0.26) were demonstrated. Shorter time interval from stroke onset to imaging in the IHS group (IHS, 80±88 versus COS, 216±292 minutes) was observed. The imaging‐to‐arterial‐puncture time was not significantly different between the groups (IHS, 160±140 versus COS, 162±184 minutes; P =0.85). Conclusions EVT in patients with IHS is safe and feasible, with comparable functional and safety outcomes to patients with COS, in this national stroke registry. Continued efforts are required to improve the inpatient stroke workflow in recognizing stroke symptoms and initiating reperfusion treatment for eligible patients with IHS.

Patterns in the Number of Interventionalists for Endovascular Treatment of Acute Ischemic Stroke in the US (P8-5.006)

<h3>Objective:</h3> To examine associations between the number of neuro-interventionalists at a hospital and acute ischemic stroke (AIS) outcomes. <h3>Background:</h3> Endovascular thrombectomy has become the standard of care for large vessel occlusion AIS involving the anterior circulation. Hence, the need for neuro-interventionalists is growing. There is limited data describing the number of interventionalists per hospital in the US, and correlations with outcomes. <h3>Design/Methods:</h3> We used complete Medicare datasets and included all AIS admissions from 2018–2019, using validated International Classification of Diseases, 10th Revision, Clinical Modification codes to identify AIS and co-morbidities. We used National Provider Identifier codes to identify distinct interventionalists at the hospital. We examined outcomes at the hospital level, including percent of AIS 1) with inpatient mortality, 2) with discharge home, and 3) with 30-day mortality. <h3>Results:</h3> Among 471427 AIS admissions, 16253 received ET. Only 683 of 4576 AIS-treating hospitals provided ET (14.9%). These hospitals most frequently only had one interventionalist available and were clustered in large metropolitan areas with high AIS volumes. As AIS volumes, ET volumes, and mean NIHSS scores increased, so did the number of interventionalists. With each additional interventionalist, there was an increased likelihood of poor outcomes at the hospital level including percent of AIS with 1) inpatient mortality (difference in percent with each additional interventionalist 0.13 SE 0.03, p&lt;0.0001), 2) discharge home (−0.17, SE 0.07, p=0.022), and 3) 30-day mortality (0.23, SE 0.04, p&lt;0.0001). <h3>Conclusions:</h3> We confirmed a relative lack of neuro-interventionalists among US hospitals, with a concentration of interventionalists in urban, high-volume centers. Although we found an increasing likelihood of poor outcomes associated with increasing number of interventionalists, this is likely due to increasing complexity and severity of cases at high-volume ET centers, but further study is needed. <b>Disclosure:</b> Dr. Tripathi has nothing to disclose. The institution of Dr. Stein has received research support from American Heart Association. Dr. Dhamoon has received personal compensation in the range of $10,000-$49,999 for serving as an Expert Witness for Faegre Baker Daniels LLP. Dr. Dhamoon has received personal compensation in the range of $10,000-$49,999 for serving as an Expert Witness for Wellstar Health System Inc. Dr. Dhamoon has received personal compensation in the range of $10,000-$49,999 for serving as an Expert Witness for Fabiani Cohen &amp; Hall, LLP. Dr. Dhamoon has received personal compensation in the range of $5,000-$9,999 for serving as an Expert Witness for Kramer, Dillof, Livingston &amp; Moore. Dr. Dhamoon has received personal compensation in the range of $500-$4,999 for serving as an Expert Witness for Robins Kaplan. Dr. Dhamoon has received personal compensation in the range of $5,000-$9,999 for serving as an Expert Witness for Parker Waichman LLP. Dr. Dhamoon has received personal compensation in the range of $500-$4,999 for serving as an Expert Witness for Heidell, Pittoni, Murphy &amp; Bach, LLP.

A Retained Microcatheter Fragment in the middle cerebral artery: report of a rare complication

Mechanical thrombectomy is now a recommended treatment for large vessel occlusion in acute ischemic stroke. However, it is associated with a number of complications, which need to be minimized and effectively managed to maximize the benefits of thrombectomy. We describe an unusual and rare complication of microcatheter fracture after a successful thrombectomy for middle cerebral artery occlusion. Due to a lack of possibilities to remove it, we decided to manage it conservatively. Subsequently, the microcatheter fragment did not interrupt normal blood flow through the artery, and the patient has been doing well without neurological sequelae. Systematic reporting of such complications will aid in the design and development of thrombectomy devices in the future.

A retained microcatheter fragment in the middle cerebral artery: Report of a rare complication

Mechanical thrombectomy is now a recommended treatment for large vessel occlusion in acute ischemic stroke. However, it is associated with a number of complications, which need to be minimized and effectively managed to maximize the benefits of thrombectomy.

A Decade of Improvement in Door‐to‐Puncture Times for Mechanical Thrombectomy But Ongoing Stagnation in Prehospital Care

Background Systems of care surrounding endovascular therapy for stroke have garnered much attention in recent years. In‐hospital metrics, such as “door‐to‐puncture” and procedure times have been areas for quality improvement. The temporal trend and clinical significance of prehospital “onset‐to‐door” time, however, remains unknown. Methods We performed a systematic review of time metric data from all published randomized controlled and investigational device exemption trials involving endovascular therapy for stroke between 2005 and 2019 (n=26). Second, we conducted a record‐level observational analysis on a total of 3512 patients from 3 real‐world registries (Mechanical Embolus Removal in Cerebral Ischemia [MERCI], Thrombectomy REvascularization of Large Vessel Occlusions in Acute Ischemic Stroke [TREVO], and TREVO Stent‐Retriever Acute Stroke [TRACK]), together with 4 prospective trials (MERCI trial, Multi‐MERCI, TREVO‐EU, and TREVO‐2). Only patients receiving mechanical thrombectomy within 9 hours from onset‐to‐puncture time were included. Predictors of good outcome were identified using generalized linear mixed modeling. Results Door‐to‐puncture times (slope=−5.83 min/y; R 2 =0.25; P =0.046), procedure times (slope=−3.78 min/y; R 2 =0.54; P &lt;0.001), and onset‐to‐reperfusion times (slope=−11.82 min/y; R 2 =0.57; P &lt;0.001) improved over the years among previously published randomized controlled trials/investigational device exemption trials from 2005 to 2019. The prehospital metric of onset‐to‐door time, however, remained statistically unchanged (slope=1.03 min/y; R 2 &lt;0.01; P =0.806). Pooled analysis from record‐level data demonstrated a similar temporal trend where door‐to‐puncture, procedure, and onset‐to‐reperfusion times declined by an average of 12 minutes (R 2 =0.45; P &lt;0.0001), 6 minutes (R 2 =0.27; P &lt;0.0001), and 8 minutes per year (R 2 =0.18; P &lt;0.0001), respectively, over a similar time period. Time from onset to door, however, did not improve (3.6 min/y; R 2 =0.34; P =0.005). In a backward‐selection regression model, onset‐to‐door time was found to be a significant predictor of patient outcomes, where every hour delay in hospital arrival correlated with a 14% reduction in the odds of a good outcome. Conclusions “Door‐to‐puncture” and procedure times have seen significant improvements over the past decade. The prehospital component of “onset‐to‐door” time, however, has remained stagnant. This presents an unrealized opportunity to enhance patient outcomes through improved systems of care in the prehospital setting.