Mechanical Thrombectomy For Large Vessel Occlusion Research Articles

Abstract WP192: Impact of Second Line Thrombectomy Technique Following Failed First Pass Thrombectomy for Anterior Circulation Stroke: To Switch or Not to Switch?

Introduction: Despite comparable outcomes for different frontline techniques in mechanical thrombectomy (MT) for acute ischemic stroke (AIS), there are sparse data regarding if and when to switch techniques if the first pass is unsuccessful. We aimed to investigate the impact of converting from one MT technique to another on the second MT attempt for AIS among patients with large vessel occlusion (LVO). Methods: This was a retrospective observational study using data from the large multicenter international Stroke Thrombectomy and Aneurysm Registry (STAR). Data from 29 stroke centers for 10,229 AIS patients treated with MT for LVO between January 2010 and December 2022 was investigated. The primary outcome measure was successful recanalization defined as modified Thrombolysis in Cerebral Ischemia (mTICI) score of 2b or higher. 90-day modified Rankin score (mRS) 0-2, mortality and symptomatic hemorrhage were used as secondary outcomes. Clinical and technical outcomes after the second MT attempt were compared between those with or without technique conversion. Results: Among 10,229 AIS patients, 1,797 AIS patients with LVO failed first pass recanalization and were included in this retrospective analysis. 927 patients were female (52%) and median (interquartile range) age was 72 (61-81) years. Converting to alternative techniques following a first failed attempt was more likely to be associated with successful recanalization at the second attempt (adjusted odds ratio 2.30, 95% CI: 1.37-3.86, P = 0.002) and 90-day good clinical outcome (adjusted odds ratio 2.10, 95% CI: 1.15-3.85, P = 0.02) after multivariate adjustment. Conclusions: This study demonstrates better clinical and technical outcomes with conversion of MT technique for the second attempt in AIS patients with LVO who failed first pass recanalization.

Mechanical Thrombectomy for All LVO – Is It Feasible? – Recent Evidence to Expand the Current Stroke Guidelines

Mechanical thrombectomy (MT) has established its role as a standard care of acute ischemic stroke due to large vessel occlusion (LVO). Current early stroke management guidelines have defined certain selection criteria for LVO patients undergoing MT to achieve the most benefit. However, it is still uncertain if some other LVO patients who do not meet these criteria can also benefit from MT. In this review, we research the latest evidence on efficacy and safety of MT for LVO in various unique stroke populations, such as advanced age, pre-stroke disability, LVO with minor stroke, large infarct volume, poor mismatch profile, very late time window, posterior circulation LVO and distal medium-sized vessel occlusions. By comparing the benefits and risks of MT with best medical management only, we may develop further subgroup-specific criteria to expand our capacity to best treat these unique LVO populations.

Safety Profile of Intra-Arterial Tirofiban as a Rescue Therapy during Mechanical Thrombectomy in Acute Ischemic Stroke

Abstract Purpose This article studies the safety profile and role of intra-arterial (IA) tirofiban as a rescue therapy in acute ischemic stroke (AIS) patients undergoing mechanical thrombectomy. Methods This is a retrospective observational study conducted among AIS patients with large vessel occlusion (LVO) eligible for endovascular revascularization and in whom IA tirofiban is given as rescue therapy. If the target vessel shows reocclusion following initial recanalization, flow limiting or significant residual stenosis after thrombectomy, or requires balloon angioplasty or stenting, IA tirofiban at a dose of 0.4 μg/kg/min was administered through the microcatheter in the target vessel followed by intravenous infusion of 0.1 μg/kg/min. The primary safety measure of the study was the incidence of symptomatic hemorrhage. Results The total number of patients in the study group was 82, 36 were in the tirofiban group and 46 were in the non-tirofiban group. Immediate successful reperfusion was achieved in 31 patients (86.1%) and 41 patients (89%) in the tirofiban and non-tirofiban groups, respectively. Note that 19.4 and 25% of patients in the tirofiban group required adjunct techniques of angioplasty and stenting, respectively. Also, 2.7% patient in the tirofiban group had a symptomatic hemorrhage, while 8.7% in the non-tirofiban group had symptomatic intracranial hemorrhage. On multinomial logistic regression, history of transient ischemic attack, truncal occlusion and watershed infarct pattern predicted the usage of IA tirofiban during mechanical thrombectomy. Conclusion Usage of IA tirofiban with or without adjunct techniques as a rescue therapy during mechanical thrombectomy in LVO improved recanalization rates without increasing the risk of symptomatic hemorrhage.

Comparative Outcomes of Mechanical Thrombectomy in Acute Ischemic Stroke Patients with ASPECTS 2-3 vs. 4-5

BackgroundThe influence of Alberta Stroke Program Early CT Score (ASPECTS) on outcomes following mechanical thrombectomy (MT) for acute ischemic stroke (AIS) patients with low ASPECTS remains unknown. In this study, we compared the outcomes of AIS patients treated with MT for large vessel occlusion (LVO) categorized by ASPECTS value. MethodsWe conducted a retrospective analysis involving 305 patients with AIS caused by LVO, defined as the occlusion of the internal carotid artery and/or the M1 segments of the middle cerebral artery, stratified into two groups: ASPECTS 2-3 and 4-5. The primary outcome was favorable outcome defined as a 90-day modified Rankin Scale (mRS) score of 0-3. Secondary outcomes were 90-day mRS 0-2, 90-day mortality, any intracerebral hemorrhage (ICH), and symptomatic ICH (sICH). We performed multivariable logistic regression analysis to evaluate the impact of ASPECTS 2-3 vs. 4-5 on outcomes. ResultsFifty-nine patients (19.3%) had ASPECTS 2-3 and 246 (80.7%) had ASPECTS 4-5. Favorable outcomes showed no significant difference between the two groups (adjusted odds ratio [aOR]= 1.13, 95% confidence interval [CI]: 0.52-2.41, p=0.80). There were also no significant differences in 90-day mRS 0-2 (aOR= 1.65, 95% CI: 0.66-3.99, p=0.30), 90-day mortality (aOR= 1.14, 95% CI: 0.58-2.20, p=0.70), any ICH (aOR= 0.54, 95% CI: 0.28-1.00, p=0.06), and sICH (aOR= 0.70, 95% CI: 0.27-1.63, p = 0.40) between the groups. ConclusionsAIS patients with LVO undergoing MT with ASPECTS 2-3 had similar outcomes compared to ASPECTS 4-5.

Abstract 246: Effect of platelet count on outcome in ischemic stroke patients with LVO undergoing MT;a meta‐analysis

Introduction Large randomized clinical trials have established the superiority of Mechanical Thrombectomy (MT) for the treatment of Large Vessel occlusion (LVO) in patients with Acute Ischemic stroke (AIS) in terms of revascularization rates and clinical outcomes as compared to IV‐tPA alone.(1, 2, 3) However, Data regarding outcomes of mechanical thrombectomy in patients with low platelets is limited and shows conflicting results. (4, 5, 6, 7, 8) Methods This meta‐analysis was performed according to the preferred reporting items for systematic review and meta‐analysis (PRISMA) guidelines.(9) We defined thrombocytopenia as platelet count < 150,000 /μL. We further classified these patients into two groups: 1) Mild thrombocytopenia (Platelet count 100,000 – 149,000 /μL) and 2) Moderate to severe thrombocytopenia (Platelet count <100,000 /μL). The favourable outcome was 90‐day functional independence, designated as an Modified Rankin Score (MRS) ≤ 2 at 90 days. Unfavorable outcomes were 1) Symptomatic Intracranial hemorrhage (sICH) and 2) Mortality at 90 days. Results All studies were determined to be of good/high quality (Newcastle Ottawa scale).(10) Compared to patients with normal platelets, Patients with low platelets (< 150,000 /μL) had a statistically significant worse outcome (mRS >2 )at 90 days (RR 0.80 [95% CI: 0.69 ‐ 0.94] p = 0.006). However, on analysis based on different platelet cutoff values, the difference in mRS score was not statistically significant in patients with Mild low platelets (100,000 – 149,000 /μL) (RR 0.84 [95% CI: 0.70 ‐ 1.00] p = 0.05) and moderate/severely low platelets (< 100,000 /μL) (RR 0.71 [95% CI: 0.48 ‐ 1.06] p = 0.09) when compared to patients with normal platelets. Similarly, Mortality was significantly increased in patients in the low platelet group (RR 1.95 [95% CI: 1.62 ‐ 2.36] p < 0.00001). Mortality was also significantly increased in the mild low platelet subgroup (RR 1.88 [ 95% CI: 1.34 ‐ 2.63] p = 0.0002) and moderate/severe low platelet subgroup (RR 2.07 [95% CI: 1.46 ‐ 2.92] p < 0.0001) when compared to patients with normal platelets. Furthermore, sICH events were significantly increased in patients in the low platelet group (RR 2.47 [95% CI: 1.51 ‐ 4.05] p = 0.0003). Similarly, on analysis based on different platelet cutoff values, sICH was also significantly increased in the mild low platelet subgroup (RR 2.34 [ 95% CI: 1.24 ‐ 4.40] p = 0.008) and moderate/severe low platelet subgroup (RR 4.13 [95% CI: 2.00 ‐ 8.50] p = 0.0001). Conclusion Our meta‐analysis revealed that compared to individuals with normal platelet count, those with platelet count (< 150,000 /μL) had worse functional outcomes (MRS ≤ 2) , higher mortality rates, and a greater incidence of sICH. However, on analysis based on different platelet cutoffs, difference in MRS score was insignificant while the mortality rates and sICH incidence remained significantly higher. This may be attributed to smaller number of studies in the “cut‐off” groups leading to decreased power. Nevertheless, our findings suggest that MT for LVO in patients with low platelets leads to worse outcomes, however these risk were not significant in group with mild thrombocytopenia. Hence, Clinicians should carefully monitor for these risks while performing procedure or post procedure care.

Endotheliitis and cytokine storm as a mechanism of clot formation in COVID-19 ischemic stroke patients: A histopathologic study of retrieved clots.

Studies during the COVID-19 pandemic have demonstrated an association between COVID-19 virus infection and the development of acute ischemic stroke, particularly large vessel occlusion (LVO). Studying the characteristics and immunohistochemistry of retrieved stroke emboli during mechanical thrombectomy for LVO may offer insights into the pathogenesis of LVO in COVID-19 patients. We examined retrieved COVID-19 emboli from the STRIP, EXCELLENT, and RESTORE registries and compared their characteristics to a control group. We identified COVID-positive LVO patients from the STRIP, RESTORE, and EXCELLENT studies who underwent mechanical thrombectomy. These patients were matched to a control group controlling for stroke etiology based on Trial of Org 10172 in Acute Stroke Treatment criteria. All clots were stained with Martius Scarlet Blue (MSB) along with immunohistochemistry for interleukin-6 (IL-6), C-reactive protein (CRP), von Willebrand factor (vWF), CD66b, fibrinogen, and citrullinated Histone H3. Clot composition was compared between groups. Nineteen COVID-19-positive patients and 38 controls were included. COVID-19-positive patients had a significantly higher percentage of CRP and vWF. There was no difference in IL-6, fibrin, CD66b, or citrullinated Histone H3 between groups. Based on MSB staining, there was no statistically significant difference regarding the percentage of red blood cells, white blood cells, fibrin, and platelets. Our study found higher concentrations of CRP and vWF in retrieved clots of COVID-19-positive stroke patients compared to COVID-19-negative controls. These findings support the potential role of systemic inflammation as indicated by elevated CRP and endothelial injury as indicated by elevated vWF as precipitating factors in thrombus development in these patients.

Concurrent bacterial endocarditis is associated with worse inpatient outcomes for large vessel occlusions

BackgroundNeurological complications of bacterial endocarditis (BE) are common, including acute ischemic stroke (AIS). Although mechanical thrombectomy (MT) is effective for large vessel occlusion (LVO) stroke, data are limited on MT...

Prognostic value of multiphase CT angiography: estimated infarct core volume in the patients with acute ischaemic stroke after mechanical thrombectomy

Recent studies reported the feasibility of quantifying a reliable infarct core (IC) volume using multiphase computed tomography (mCTA) based on deep learning, however its prognostic value was not fully clarified. Therefore, we aimed to evaluate the prognostic value of mCTA-estimated IC volume in patients with acute ischemic stroke (AIS) after mechanical thrombectomy (MT). We retrospectively reviewed patients who underwent mCTA and MT for large vessel occlusion in middle cerebral artery and (or) internal carotid artery within 6 hours after symptom onset between January 2018 and November 2019. Patients were dichotomized into good (modified Rankin Scale [mRS] score, 0-2) and poor (mRS, 3-6) outcome groups. mCTA-estimated IC volume were generated based on a multi-scale three-dimensional convolutional neural network. Univariate, multivariate logistic regression and receiver operating characteristic (ROC) curve analyses were used to identify the independent variables, and evaluate their performances in predicting the clinical outcome. Of 44 included patients, 27 (61.4%) patients achieved good outcome. National Institutes of Health Stroke Scale scores at admission [NIHSSpre] (odds ratio [OR], 1.191; 95%confidence interval [CI], 1.028-1.379; P=0.020) and mCTA-estimated IC volume (OR, 1.076; 95%CI, 1.016-1.140; P=0.013) were found to be independently associated with functional outcome in patients with AIS after MT. After integrating NIHSSpre and mCTA-estimated IC volume, optimal performance (area under the ROC curve, 0.874; 95%CI, 0.739-0.954) could be obtained in predicting the clinical outcome. mCTA-estimated IC volume might be promising for predicting the prognosis, and assisting in making individualized treatment decision in patients with AIS.

Underlying intracranial atherosclerotic disease is associated with worse outcomes in acute large vessel occlusion undergoing endovascular thrombectomy

BackgroundData on large vessel occlusion (LVO) management due to intracranial atherosclerotic disease (ICAD) are scarce. ObjectiveTo compare clinical outcomes between patients with ICAD and those without ICAD following mechanical thrombectomy (MT). MethodsWe performed a retrospective analysis of consecutive patients who underwent MT for LVO in a large academic comprehensive stroke center, and compared in-hospital mortality, 90-day mortality, favorable functional outcome at 90 days, and symptomatic intracranial hemorrhage (ICH) using chi-squared tests and multivariate logistic regression analyses. We defined ICAD as observable plaque at occlusion site post-thrombectomy. ResultsAmong 215 patients (mean age 67.1 ± 16.0 years; 60.5% female; 83.6% Black, median NIHSS score 16), ICAD was present in 38 patients (17.7%). Diabetes and dyslipidemia were more common in those with ICAD (57.9% vs. 38.4%, p = 0.027 and 29.0% vs. 14.7%, p = 0.035, respectively). Substantial reperfusion (TICI ≥2b) was achieved less often (84.2% vs. 94.4%, p = 0.031) but symptomatic ICH was also less common in ICAD patients (0% vs. 9.0%, p = 0.081). In-hospital and 90-day mortality were more common (36.8% vs. 15.8%, p = 0.003 and 52.6% vs. 26.6%, p = 0.002, respectively) and favorable functional outcome (mRS 0-2) at 90 days was less common (7.9% vs. 33.9%, p = 0.001) in ICAD patients. After adjusting for prognostic variables, ICAD was independently associated with in-hospital mortality (OR=4.1, 95% CI 1.7-9.7), 90-day mortality (OR=3.7, 95% CI 1.6-8.6), and poor functional outcome at 90 days (OR=5.5, 95% CI 1.6-19.4). ConclusionSymptomatic ICAD in a predominantly African American cohort is associated with increased odds of mortality and poor functional outcome at 90 days in patients with LVO undergoing MT.

Association between population changes and the number of endovascular thrombectomies.

Randomized controlled trials have demonstrated the efficacy of mechanical thrombectomy (MT) for acute ischemic stroke. However, few studies indicate an association between the number of mechanical thrombectomies and population changes. We aimed to clarify the association between population changes and the number of mechanical thrombectomies for proper allocation of limited medical resources. We retrospectively analyzed data from 162 patients who underwent MT for large vessel occlusion at our hospitals and compared the number of mechanical thrombectomies per 100,000 person/year to population changes in five regions covered by our hospitals within 2015-2016 and 2017-2019. We performed a simple linear regression analysis to determine the association between population changes and the number of mechanical thrombectomies. Overall, the number of mechanical thrombectomies increased from 15.1 to 19. However, a significant decrease was noted in Toya Lake and Sobetsu/Toyoura. Furthermore, there was a significant negative linear correlation between the overall population reduction rate and the number of mechanical thrombectomies and a positive linear correlation between the increased proportion of the population aged >65 years and the number of mechanical thrombectomies. The number of mechanical thrombectomies may decrease in areas where the overall population reduction rate exceeds 8% or the increased rate of the population aged >65 years is <4%. However, it is necessary to continue establishing a system for MT in areas that have yet to reach these levels.

Tissue Clock Beyond Time Clock: Endovascular Thrombectomy for Patients With Large Vessel Occlusion Stroke Beyond 24 Hours.

Randomized trials proved the benefits of mechanical thrombectomy (MT) for select patients with large vessel occlusion (LVO) within 24 hours of last-known-well (LKW). Recent data suggest that LVO patients may benefit from MT beyond 24 hours. This study reports the safety and outcomes of MT beyond 24 hours of LKW compared to standard medical therapy (SMT). This is a retrospective analysis of LVO patients presented to 11 comprehensive stroke centers in the United States beyond 24 hours from LKW between January 2015 and December 2021. We assessed 90-day outcomes using the modified Rankin Scale (mRS). Of 334 patients presented with LVO beyond 24 hours, 64% received MT and 36% received SMT only. Patients who received MT were older (67±15 vs. 64±15 years, P=0.047) and had a higher baseline National Institutes of Health Stroke Scale (NIHSS; 16±7 vs.10±9, P<0.001). Successful recanalization (modified thrombolysis in cerebral infarction score 2b-3) was achieved in 83%, and 5.6% had symptomatic intracranial hemorrhage compared to 2.5% in the SMT group (P=0.19). MT was associated with mRS 0-2 at 90 days (adjusted odds ratio [aOR] 5.73, P=0.026), less mortality (34% vs. 63%, P<0.001), and better discharge NIHSS (P<0.001) compared to SMT in patients with baseline NIHSS ≥6. This treatment benefit remained after matching both groups. Age (aOR 0.94, P<0.001), baseline NIHSS (aOR 0.91, P=0.017), Alberta Stroke Program Early Computed Tomography (ASPECTS) score ≥8 (aOR 3.06, P=0.041), and collaterals scores (aOR 1.41, P=0.027) were associated with 90-day functional independence. In patients with salvageable brain tissue, MT for LVO beyond 24 hours appears to improve outcomes compared to SMT, especially in patients with severe strokes. Patients' age, ASPECTS, collaterals, and baseline NIHSS score should be considered before discounting MT merely based on LKW.

CT-based thrombus radiomics nomogram for predicting secondary embolization during mechanical thrombectomy for large vessel occlusion.

Secondary embolization (SE) during mechanical thrombectomy (MT) for cerebral large vessel occlusion (LVO) could reduce the anterior blood flow and worsen clinical outcomes. The current SE prediction tools have limited accuracy. In this study, we aimed to develop a nomogram to predict SE following MT for LVO based on clinical features and radiomics extracted from computed tomography (CT) images. A total of 61 patients with LVO stroke treated by MT at Beijing Hospital were included in this retrospective study, of whom 27 developed SE during the MT procedure. The patients were randomly divided (7:3) into training (n = 42) and testing (n = 19) cohorts. The thrombus radiomics features were extracted from the pre-interventional thin-slice CT images, and the conventional clinical and radiological indicators associated with SE were recorded. A support vector machine (SVM) learning model with 5-fold cross-verification was used to obtain the radiomics and clinical signatures. For both signatures, a prediction nomogram for SE was constructed. The signatures were then combined using the logistic regression analysis to construct a combined clinical radiomics nomogram. In the training cohort, the area under the receiver operating characteristic curve (AUC) of the nomograms was 0.963 for the combined model, 0.911 for the radiomics, and 0.891 for the clinical model. Following validation, the AUCs were 0.762 for the combined model, 0.714 for the radiomics model, and 0.637 for the clinical model. The combined clinical and radiomics nomogram had the best prediction accuracy in both the training and test cohort. This nomogram could be used to optimize the surgical MT procedure for LVO based on the risk of developing SE.

Development of a clot-adhesive coating to improve the performance of thrombectomy devices

BackgroundThe first-pass complete recanalization by mechanical thrombectomy (MT) for the treatment of stroke remains limited due to the poor integration of the clot within current devices. Aspiration can help retrieval...

Abstract Number ‐ 189: Comparative Device Analysis for First Pass Stent Retriever Mechanical Thrombectomy

Introduction Limited data is available regarding comparative outcomes amongst FDA‐approved devices for mechanical thrombectomy (MT). The objective of this study is to assess procedural efficacy, clinical outcomes, and safety of currently available stent retriever devices when used during first pass thrombectomy for acute ischemic stroke. Methods A retrospective analysis was performed on all patients who underwent MT for large vessel occlusion (LVO) at a single comprehensive stroke center between January 2016 and January 2022. All patients who underwent MT with a stent retriever (Solitaire, Embotrap, Trevo) during first pass were included in the analysis. Primary efficacy and safety outcomes included time to recanalization, attainment of first‐pass effect (FPE), recanalization TICI score, 90‐day modified Rankin scale (mRS), and incidence of hemorrhagic transformation. One‐way ANOVA was used to compare median time to recanalization amongst cohorts. Chi‐squared test was used to compare frequencies of outcome measures amongst cohorts. Results During the study period, 234 patients underwent MT for LVO with use of stent retriever device during the first pass. In these cases, the type of stent retriever utilized was Solitaire (n = 163), Embotrap (n = 45), or Trevo (n = 26). There were no significant differences between cohorts in terms of age, gender, ethnicity, initial NIH stroke scale, or level of occlusion, or comorbidities. No significant differences were observed between cohorts for any primary outcome measures. The median time to recanalization was 53 min [Solitaire], 49 min [Embotrap], 63 min [Trevo] (p = 0.17). First‐pass effect was attained in 28.6% [Solitaire], 38.4% [Embotrap], 26.9% [Trevo] (p = 0.41). TICI 2b or greater recanalization was attained in 80.3% [Solitaire], 88.9% [Embotrap], 84.6% [Trevo] (p = 0.38). 90‐day mRS of 0–2 was observed in 36.6% [Solitaire], 38.9% [Embotrap], 34.8% [Trevo] (p = 0.95). Hemorrhagic transformation was observed in 45.9% [Solitaire], 36.8% [Embotrap], 34.6% [Trevo] (p = 0.40). Conclusions The type of stent retriever chosen for first pass thrombectomy did not predict procedural efficacy, clinical outcomes, or safety in our single center analysis.

Abstract Number ‐ 163: Underlying ICAD is associated with worse outcomes in acute large vessel occlusion undergoing endovascular thrombectomy

Introduction Acute large vessel occlusion (LVO) can be secondary to thromboembolism or intracranial atherosclerotic disease (ICAD). Data on LVO management due to underlying ICAD are scarce. We hypothesized that patients with ICAD have worse clinical outcomes following mechanical thrombectomy (MT) than those without ICAD. Methods We performed a retrospective analysis of consecutive patients who underwent MT for LVO in a large academic comprehensive stroke center between January 14, 2018 and October 24, 2021. Presence of ICAD at LVO site was determined by the interventionalist. We compared in‐hospital mortality, 90‐day mortality, and 90‐day modified Rankin Scale (mRS) scores between those with and without ICAD, in unadjusted and adjusting logistic regression models. Results Among 215 patients (mean age 67.1±16.0 years; 60.5% female; 80.5% Black, median NIHSS score 16), ICAD was present in 38 patients (17.7%). Diabetes and dyslipidemia were more common in those with ICAD (57.9% vs. 38.4%, p = 0.027 and 29.0% vs. 14.7%, p = 0.035, respectively). Substantial reperfusion (TICI ≥ 2b) was achieved less often (84.2% vs. 94.4%, p = 0.031) but symptomatic ICH was also less common in ICAD patients (0% vs. 9.0%, p = 0.054). In‐hospital and 90‐day mortality were more common (36.8% vs. 15.8%, p = 0.003 and 52.6% vs. 26.6%, p = 0.002, respectively) and favorable functional outcome (mRS 0–2) at 90 days was less common (7.9% vs. 33.9%, p = 0.001) in ICAD patients. After adjusting for prognostic variables, ICAD was independently associated with in‐hospital mortality (OR = 4.1, 95% CI 1.7‐9.7), 90‐day mortality (OR = 3.7, 95% CI 1.6‐8.6), and poor functional outcome at 90 days (OR = 5.5, 95% CI 1.6‐19.4). Conclusions Symptomatic ICAD in a predominantly African American cohort is associated with increased odds of mortality and poor functional outcome at 90 days in patients with LVO undergoing MT. Further research is warranted to understand factors associated with worse outcomes and investigate alternative interventional approaches and medical management in this high‐risk population.

Abstract WMP86: Risk Of Hemorrhagic Transformation Is Related To Severity Of Hba1c Elevation In Patients Undergoing Mechanical Thrombectomy

Introduction: While prior studies have demonstrated hyperglycemia as an independent predictor of hemorrhagic transformation and poor clinical outcome following Mechanical Thrombectomy (MT), it is less clear to what extent HbA1c impacts these relationships. The objective of this study was to assess the association between severity of poor glycemic control, functional independence and hemorrhagic transformation. Methods: A retrospective analysis was performed on patients who underwent MT for large vessel occlusion (LVO) at a single comprehensive stroke center between January 2016 and January 2022. Primary safety and efficacy outcomes included the presence of hemorrhagic transformation and good 90-day functional outcome defined as modified Rankin scale (mRS) of 0-2. Good glycemic control was described as HbA1c &lt;6.4 mg/dl. Fisher’s Exact Probability Test was used to compare cohorts to those with good glycemic control and calculate odds ratios for given outcomes. Results: 657 patients were included in the analysis. Among these, the observed HbA1c value was &lt;6.5 (n=535), 6.5-8.0 (n=72), or &gt;8.0 (n=50). There were no significant differences between cohorts in terms of age, gender, ethnicity, initial NIH stroke scale, level of occlusion, or medical comorbidities. Patients with HbA1c ≥6.5 had a 17.0% lower incidence of good functional outcome vs those with good glycemic control (OR 0.47, CI: 0.32-0.88). An HbA1c threshold of ≥6.5 did not correlate with significant differences in HT incidence (OR 1.08, CI: 0.76-1.79). However, patients with HbA1c &gt; 8.0 had a 14.8% higher incidence of HT vs those with good glycemic control (OR 1.81, CI: 1.15-4.35). Conclusions: While suboptimal glucose control and diabetes (HbA1c ≥6.5) is associated with worse outcomes following MT for acute ischemic stroke, its effect on hemorrhagic transformation risk was only seen in those with poor glycemic control (HbA1c &gt;8.0) in our single center analysis.

Abstract TP135: Underlying Intracranial Atherosclerotic Disease Is Associated With Worse Outcomes In Acute Large Vessel Occlusion Undergoing Endovascular Thrombectomy

Introduction: Acute large vessel occlusion (LVO) can be secondary to thromboembolism or intracranial atherosclerotic disease (ICAD). Data on LVO management due to underlying ICAD are scarce. We hypothesized that patients with ICAD have worse clinical outcomes following mechanical thrombectomy (MT) than those without ICAD. Methods: We performed a retrospective analysis of consecutive patients who underwent MT for LVO in a large academic comprehensive stroke center between January 14, 2018 and October 24, 2021. Presence of ICAD at LVO site was determined by the interventionalist. We compared in-hospital mortality, 90-day mortality, and 90-day modified Rankin Scale (mRS) scores between those with and without ICAD, in unadjusted and adjusting logistic regression models. Results: Among 215 patients (mean age 67.1±16.0 years; 60.5% female; 80.5% Black, median NIHSS score 16), ICAD was present in 38 patients (17.7%). Diabetes and dyslipidemia were more common in those with ICAD (57.9% vs. 38.4%, p=0.027 and 29.0% vs. 14.7%, p=0.035, respectively). Substantial reperfusion (TICI ≥2b) was achieved less often (84.2% vs. 94.4%, p=0.031) but symptomatic ICH was also less common in ICAD patients (0% vs. 9.0%, p=0.054). In-hospital and 90-day mortality were more common (36.8% vs. 15.8%, p=0.003 and 52.6% vs. 26.6%, p=0.002, respectively) and favorable functional outcome (mRS 0-2) at 90 days was less common (7.9% vs. 33.9%, p=0.001) in ICAD patients. After adjusting for prognostic variables, ICAD was independently associated with in-hospital mortality (OR=4.1, 95% CI 1.7-9.7), 90-day mortality (OR=3.7, 95% CI 1.6-8.6), and poor functional outcome at 90 days (OR=5.5, 95% CI 1.6-19.4). Conclusions: Symptomatic ICAD in a predominantly African American cohort is associated with increased odds of mortality and poor functional outcome at 90 days in patients with LVO undergoing MT. Further research is warranted to understand factors associated with worse outcomes and investigate alternative interventional approaches and medical management in this high-risk population.

Prognostic significance of age within the adolescent and young adult acute ischemic stroke population after mechanical thrombectomy: insights from STAR.

Although younger adults have been shown to have better functional outcomes after mechanical thrombectomy (MT) for acute ischemic stroke (AIS), the significance of this relationship in the adolescent and young adult (AYA) population is not well defined given its undefined rarity. Correspondingly, the goal of this study was to determine the prognostic significance of age in this specific demographic following MT for large-vessel occlusions. A prospectively maintained international multi-institutional database, STAR (Stroke Thrombectomy and Aneurysm Registry), was reviewed for all patients aged 12-18 (adolescent) and 19-25 (young adult) years. Parameters were compared using chi-square and t-test analyses, and associations were interrogated using regression analyses. Of 7192 patients in the registry, 41 (0.6%) satisfied all criteria, with a mean age of 19.7 ± 3.3 years. The majority were male (59%) and young adults (61%) versus adolescents (39%). The median prestroke modified Rankin Scale (mRS) score was 0 (range 0-2). Strokes were most common in the anterior circulation (88%), with the middle cerebral artery being the most common vessel (59%). The mean onset-to-groin puncture and groin puncture-to-reperfusion times were 327 ± 229 and 52 ± 42 minutes, respectively. The mean number of passes was 2.2 ± 1.2, with 61% of the cohort achieving successful reperfusion. There were only 3 (7%) cases of reocclusion. The median mRS score at 90 days was 2 (range 0-6). Between the adolescent and young adult subgroups, the median mRS score at last follow-up was statistically lower in the adolescent subgroup (1 vs 2, p = 0.03), and older age was significantly associated with a higher mRS at 90 days (coefficient 0.33, p < 0.01). Although rare, MT for AIS in the AYA demographic is both safe and effective. Even within this relatively young demographic, age remains significantly associated with improved functional outcomes. The implication of age-dependent stroke outcomes after MT within the AYA demographic needs greater validation to develop effective age-specific protocols for long-term care across both pediatric and adult centers.

Mechanical Thrombectomy for Acute Ischemic Stroke due to Thrombus in the Pulmonary Vein Stump after Left Pulmonary Lobectomy: A Case Series.

Cerebral embolic stroke caused by a thrombus in the pulmonary vein stump after left pulmonary lobectomy is a serious complication. We retrospectively analyzed four patients who underwent mechanical thrombectomy for large-vessel occlusion after left pulmonary lobectomy between January 2014 and March 2022. Two cases occurred after left upper lobectomy and the others occurred after left lower lobectomy. All patients presented with cerebral embolic stroke from the day after surgery to the 9th postoperative day, and successful reperfusion was achieved in all cases. Two patients had good outcomes at 90 days. Thrombus in the pulmonary vein stump is the probable cause of cerebral embolism, and mechanical thrombectomy is effective. Further studies are required to establish preventive measures and perioperative management strategies.

Management strategies of unanticipated intracranial stenosis during mechanical thrombectomy for acute stroke: A survey of academic neurointerventionalists.

The optimal approach to the management of intracranial atherosclerotic disease (ICAD) at the time of mechanical thrombectomy (MT) for large vessel occlusion (LVO) remains controversial. The goal of this study is to characterize current practices concerning this challenging clinical situation in a survey of practicing neurointerventionalists. An electronic questionnaire was sent to a cross-section of North American academic neurointerventionalists using publicly available contact information and departmental websites. Prior to analysis, responses were anonymized and categorized by region. A total of 136/360 responses were recorded from the U.S. and Canada. The mean number of years of practicing as a neurointerventionalist among the respondents was 10.5 (± 6.2 years). ICAD was perceived as a causative factor during MT for LVO in 5-10% of thrombectomy cases. The most common first-line treatment approach for significant ICAD, assuming a TICI 2b or better reperfusion, was medical therapy (77.9% of respondents), followed by angioplasty + stent placement (8.8% of respondents). There were no significant differences in the first line treatment of ICAD in LVO between geographical regions (p = 0.815). The approach to underlying ICAD in LVO varies widely; however, the majority of neurointerventionalists prefer medical therapy with DAPT as a first-line treatment approach. The current survey highlights the need for studies that better define the optimal timing and modality of treatment, along with an evidence-based framework for balancing the risks associated with these treatment approaches.