Benefit Of Endovascular Thrombectomy Research Articles

Endovascular vs Medical Management of Acute Basilar Artery Occlusion

In several randomized clinical trials, endovascular thrombectomy led to better functional outcomes than conventional treatment at 90 days poststroke in patients with acute basilar artery occlusion. However, the long-term clinical outcomes of these patients have not been well delineated. To evaluate 1-year clinical outcomes in patients with acute basilar artery occlusion following endovascular thrombectomy vs control. This study is an extension of the ATTENTION trial, a multicenter, randomized clinical trial. Patients were included between February 2021 and January 2022, with 1-year follow-up through April 2023. This multicenter, population-based study was conducted at 36 comprehensive stroke sites. Patients with acute basilar artery occlusion within 12 hours of estimated symptom onset were included. Of the 342 patients randomized in the ATTENTION trial, 330 (96.5%) had 1-year follow-up information available. Endovascular thrombectomy (thrombectomy group) vs best medical treatment (control group). The primary outcome was defined as a score of 0 to 3 on the modified Rankin Scale (mRS) at 1 year. Secondary outcomes were functional independence (mRS score 0-2), excellent outcome (mRS score 0-1), level of disability (distribution of all 7 mRS scores), mortality, and health-related quality of life at 1 year. Among 330 patients who had 1-year follow-up data, 227 (68.8%) were male, and the mean (SD) age was 67.0 (10.7) years. An mRS score 0 to 3 at 1 year was achieved by 99 of 222 patients (44.6%) in the thrombectomy group and 21 of 108 (19.4%) in the control group (adjusted rate ratio, 2.23; 95% CI, 1.51-3.29). Mortality at 1 year compared with 90 days was more frequent in both the thrombectomy group (101 of 222 [45.5%] vs 83 of 226 [36.7%]) and the control group (69 of 108 [63.9%] vs 63 of 114 [55.3%]). Excellent outcome (mRS score 0-1) at 1 year compared with 90 days increased in the thrombectomy group (62 of 222 [27.9%] vs 45 of 226 [19.9%]) but not in the control group (9 of 108 [8.3%] vs 9 of 114 [7.9%]) resulting in a magnified treatment benefit. Among patients with basilar artery occlusion within 12 hours of onset, the benefits of endovascular thrombectomy at 1 year compared with 90 days were sustained for favorable (mRS score 0-3) outcome and enhanced for excellent (mRS score 0-1) outcome.

Endovascular Thrombectomy for Large Ischemic Stroke Across Ischemic Injury and Penumbra Profiles

Whether endovascular thrombectomy (EVT) efficacy for patients with acute ischemic stroke and large cores varies depending on the extent of ischemic injury is uncertain. To describe the relationship between imaging estimates of irreversibly injured brain (core) and at-risk regions (mismatch) and clinical outcomes and EVT treatment effect. An exploratory analysis of the SELECT2 trial, which randomized 352 adults (18-85 years) with acute ischemic stroke due to occlusion of the internal carotid or middle cerebral artery (M1 segment) and large ischemic core to EVT vs medical management (MM), across 31 global centers between October 2019 and September 2022. EVT vs MM. Primary outcome was functional outcome-90-day mRS score (0, no symptoms, to 6, death) assessed by adjusted generalized OR (aGenOR; values >1 represent more favorable outcomes). Benefit of EVT vs MM was assessed across levels of ischemic injury defined by noncontrast CT using ASPECTS score and by the volume of brain with severely reduced blood flow on CT perfusion or restricted diffusion on MRI. Among 352 patients randomized, 336 were analyzed (median age, 67 years; 139 [41.4%] female); of these, 168 (50%) were randomized to EVT, and 2 additional crossover MM patients received EVT. In an ordinal analysis of mRS at 90 days, EVT improved functional outcomes compared with MM within ASPECTS categories of 3 (aGenOR, 1.71 [95% CI, 1.04-2.81]), 4 (aGenOR, 2.01 [95% CI, 1.19-3.40]), and 5 (aGenOR, 1.85 [95% CI, 1.22-2.79]). Across strata for CT perfusion/MRI ischemic core volumes, aGenOR for EVT vs MM was 1.63 (95% CI, 1.23-2.16) for volumes ≥70 mL, 1.41 (95% CI, 0.99-2.02) for ≥100 mL, and 1.47 (95% CI, 0.84-2.56) for ≥150 mL. In the EVT group, outcomes worsened as ASPECTS decreased (aGenOR, 0.91 [95% CI, 0.82-1.00] per 1-point decrease) and as CT perfusion/MRI ischemic core volume increased (aGenOR, 0.92 [95% CI, 0.89-0.95] per 10-mL increase). No heterogeneity of EVT treatment effect was observed with or without mismatch, although few patients without mismatch were enrolled. In this exploratory analysis of a randomized clinical trial of patients with extensive ischemic stroke, EVT improved clinical outcomes across a wide spectrum of infarct volumes, although enrollment of patients with minimal penumbra volume was low. In EVT-treated patients, clinical outcomes worsened as presenting ischemic injury estimates increased. ClinicalTrials.gov Identifier: NCT03876457.

Abstract WP199: Outcomes Following Posterior Cerebral Artery Thrombolysis vs Medical Management in those with Atrial Fibrillation

Background: The benefits of endovascular thrombectomy (EVT) for posterior cerebral artery (PCA) occlusion remain controversial, but intravenous thrombolysis (IVT) has proven benefit across nearly all ischemic stroke types. We isolated a cohort of patients with likely embolic PCA occlusions (those with atrial fibrillation) and compared outcomes associated with IVT and EVT versus medical management (MM). Methods: The National Inpatient Sample (2015-2020) was retrospectively queried for patients with a primary diagnosis of a PCA occlusion (without a concomitant basilar occlusion, BAO) with a secondary diagnosis of atrial fibrillation. Descriptive statistics and propensity score matching for IVT with multivariable logistic regression were used to determine the odds of routine discharge, hospital length of stay, and death between those treated with IVT and EVT versus MM. Results: Of the 107,525 screened patients with a primary diagnosis of a PCA occlusion, 27730(25.7%) had a secondary diagnosis of atrial fibrillation, of whom 3010 underwent IVT. In a 1:1 matched cohort(n=3010 per group), patients treated with IVT had greater odds of discharge to home (adjusted OR 1.87,95% CI 1.22 to 2.87) with no difference in length of hospital stay (adjusted β 0.26, 95% -0.71 to 1.22) or in-hospital death (adjusted OR 0.81, 95% CI 0.27 to 2.47) as compared to patients treated with MM. These trends were preserved in a secondary analysis of unmatched patients in multi variable regression models, and no significant benefit of EVT for these outcomes (OR 1.75, 95%CI 0.62-4.93). Patterns were also similar when patients with a concomitant BAO were included (routine discharge adjusted OR for IVT: 1.57, 95% CI:1.03-2.38). Conclusion: Our findings show a potential real-world benefit for IVT in patients with a PCA occlusion secondary to presumed cardio embolism, but no significant advantage with EVT.

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 <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 >=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>0.79). Patient with ENW had greater MLS (5.05mm [IQR2.06-10.2] vs 0mm [IQR0-3.94, p<0.001]) MLS was associated with development of ENW (aOR 1.22, 95%CI 1.13-1.32, p<0.001), and lower likelihood of long-term functional improvement (adjusted generalized OR 0.96, 95%CI 0.92-0.97, p<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.

Endovascular Treatment of Acute Ischemic Stroke After Cardiac Interventions in the United States

Ischemic stroke is a serious complication of cardiac intervention, including surgery and percutaneous procedures. Endovascular thrombectomy (EVT) is an effective treatment for ischemic stroke and may be particularly important for cardiac intervention patients who often cannot receive intravenous thrombolysis. To examine trends in EVT for ischemic stroke during hospitalization of patients with cardiac interventions vs those without in the United States. This cohort study involved a retrospective analysis using data for 4888 US hospitals from the 2016-2020 National Inpatient Sample database. Participants included adults (age ≥18 years) with ischemic stroke (per codes from the International Statistical Classification of Diseases, Tenth Revision, Clinical Modification), who were organized into study groups of hospitalized patients with cardiac interventions vs without. Individuals were excluded from the study if they had either procedure prior to admission, EVT prior to cardiac intervention, EVT more than 3 days after admission or cardiac intervention, or endocarditis. Data were analyzed from April 2023 to October 2023. Cardiac intervention during admission. The odds of undergoing EVT by cardiac intervention status were calculated using multivariable logistic regression. Adjustments were made for stroke severity in the subgroup of patients who had a National Institutes of Health Stroke Scale (NIHSS) score documented. As a secondary outcome, the odds of discharge home by EVT status after cardiac intervention were modeled. Among 634 407 hospitalizations, the mean (SD) age of the patients was 69.8 (14.1) years, 318 363 patients (50.2%) were male, and 316 044 (49.8%) were female. A total of 12 093 had a cardiac intervention. An NIHSS score was reported in 218 576 admissions, 216 035 (34.7%) without cardiac intervention and 2541 (21.0%) with cardiac intervention (P < .001). EVT was performed in 23 660 patients (3.8%) without cardiac intervention vs 194 (1.6%) of those with cardiac intervention (P < .001). After adjustment for potential confounders, EVT was less likely to be performed in stroke patients with cardiac intervention vs those without (adjusted odds ratio [aOR], 0.27; 95% CI, 0.23-0.31), which remained consistent after adjusting for NIHSS score (aOR, 0.28; 95% CI, 0.22-0.35). Among individuals with a cardiac intervention, receiving EVT was associated with a 2-fold higher chance of discharge home (aOR, 2.21; 95% CI, 1.14-4.29). In this study, patients hospitalized with ischemic stroke and cardiac intervention may be less than half as likely to receive EVT as those without cardiac intervention. Given the known benefit of EVT, there is a need to better understand the reasons for lower rates of EVT in this patient population.

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

Endovascular therapy versus best medical management for isolated posterior cerebral artery occlusion: A systematic review and meta-analysis.

Isolated posterior cerebral artery occlusions (iPCAO) were underrepresented in pivotal randomized clinical trial (RCTs) of endovascular thrombectomy (EVT) in ischemic stroke, and the benefit of EVT in this population is still indeterminate. We performed a systematic review and a meta-analysis to compare the safety and efficacy of EVT compared to best medical management (BMM) in patients with iPCAO. We searched Medline/PubMed, Embase, Web of Science, and the Cochrane databases up to May 2023 for eligible studies reporting outcomes of patients with iPCAO treated with EVT or BMM. We pooled odds ratios (ORs) with corresponding 95% confidence intervals (CI) using a random-effects model. Seven studies involving 2560 patients were included. EVT was associated with significantly higher likelihood of early neurological improvement (OR, 2.31 [95% CI, 1.38-2.91]; p < 0.00001) and visual field normalization (OR, 3.08 [95% CI, 1.76-5.38]; p < 0.0001) compared to BMM. Rates of good functional outcomes (mRS 0-2) were comparable between the two arms (OR, 0.88 [95% CI, 0.70-1.10]; p = 0.26). Symptomatic intracranial hemorrhage (sICH) was comparable between the two groups (OR, 1.94 [95% CI, 0.96-3.93]; p = 0.07). Mortality was also similar between the two groups (OR, 1.36; [95% CI, 0.77-2.42]; p = 0.29). In patients with iPCAO, EVT was associated with visual and early neurological improvement but with a strong trend toward increased sICH. Survival and functional outcomes may be slightly poorer. The role of EVT in iPCAO remains uncertain.

Thrombectomy for proximal intracranial occlusion beyond 24 hours after time last seen normal: A narrative review

Endovascular thrombectomy (EVT) revolutionized the treatment for acute ischemic stroke due to large vessel occlusion (LVO). Current guidelines published by multiple academic societies recommend EVT for eligible patients who present within 24 hours of the time last seen well. However, more recent data suggests that extending this window past 24 hours produces more favorable outcomes in specific patients presenting with anterior circulation LVO. More specifically, recent observational data indicates a higher probability of functional independence, functional improvement, and long-term survival with EVT when compared to best medical management. Based on the available data, there is unclear equipoise in randomizing all patients with acute ischemic stroke due to LVO to EVT or medical management. However, for those patients with large established infarction, distal occlusions, or well beyond the 24-hour window, randomized clinical trials are called upon to determine whether there is benefit of EVT in these patient groups. In this narrative review, we will summarize the most recent data on EVT in the ultra extended window (&gt;24 hours after time last seen normal) and discuss further considerations of this treatment.

Outcomes with Endovascular Treatment of Patients with M2 Segment MCA Occlusion in the Late Time Window.

Randomized trials in the late window have demonstrated the efficacy and safety of endovascular thrombectomy in large-vessel occlusions. Patients with M2-segment MCA occlusions were excluded from these trials. We compared outcomes with endovascular thrombectomy in patients with M2-versus-M1 occlusions presenting 6-24 hours after symptom onset. Analyses were on pooled data from studies enrolling patients with stroke treated with endovascular thrombectomy 6-24 hours after symptom onset. We compared 90-day functional independence (mRS ≤ 2), mortality, symptomatic intracranial hemorrhage, and successful reperfusion (expanded TICI = 2b-3) between patients with M2 and M1 occlusions. The benefit of successful reperfusion was then assessed among patients with M2 occlusion. Of 461 patients, 367 (79.6%) had M1 occlusions and 94 (20.4%) had M2 occlusions. Patients with M2 occlusions were older and had lower median baseline NIHSS scores. Patients with M2 occlusion were more likely to achieve 90-day functional independence than those with M1 occlusion (adjusted OR = 2.13; 95% CI, 1.25-3.65). There were no significant differences in the proportion of successful reperfusion (82.9% versus 81.1%) or mortality (11.2% versus 17.2%). Symptomatic intracranial hemorrhage risk was lower in patients with M2-versus-M1 occlusions (4.3% versus 12.2%, P = .03). Successful reperfusion was independently associated with functional independence among patients with M2 occlusions (adjusted OR = 2.84; 95% CI, 1.11-7.29). In the late time window, patients with M2 occlusions treated with endovascular thrombectomy achieved better clinical outcomes, similar reperfusion, and lower symptomatic intracranial hemorrhage rates compared with patients with M1 occlusion. These results support the safety and benefit of endovascular thrombectomy in patients with M2 occlusions in the late window.

Abstract WMP90: Is Endovascular Thrombectomy More Effective Than IV-tPA For Distal Vessel Occlusions? Propensity Score-matched Analysis From K-net Registry

Background and Purpose: The benefit of endovascular thrombectomy (EVT) for acute ischemic stroke due to primary distal vessel occlusions is unclear. We assessed whether outcome of acute ischemic stroke patients treated with EVT for primary distal vessel occlusions was better than intravenous tissue-type plasminogen activator (IV-tPA) alone. Materials and Methods: We investigated data from K-NET Registry, which is a prospective, multicenter, observational registry of acute ischemic stroke patients treated with EVT or IV t-PA in Kanagawa, Japan. We evaluated the patients who had primally distal vessel occlusion and were treated with EVT (with or without IV-tPA) or IV tPA alone. Distal vessel occlusion was defined as middle cerebral artery M2-M3, anterior cerebral artery or posterior cerebral artery occlusion. Propensity score-matched analysis was conducted to compare outcomes between EVT and IV-tPA alone. Primary outcome was good outcome at 90 days, defined as mRS of 0 to 2 or not worsening compared to pre-stroke mRS. Safety outcome was the occurrence of all hemorrhage and symptomatic hemorrhage. Results: 703 patients with distal vessel occlusion (MCA M2, 436 cases, M3, 167 cases, ACA 48 cases, PCA 52 cases) were included in this study. 461 cases were treated with EVT and 242 were IV-tPA alone. Propensity-score matching paired 110 patients with EVT and 110 patients with IV-tPA. There were no significant differences in good clinical outcome (EVT 65.4%, IV-tAP 60.0%), all hemorrhage (EVT 15.4%, IV-tAP 11.8%) and symptomatic hemorrhage (EVT 4.5%, IV-tAP 1.8%). Dividing EVT group into EVT with IV-tPA and EVT alone, there were no significant differences in outcomes compared to IV-tPA alone. Conclusions: The benefit of EVT for acute primary distal vessel occlusions was similar as IV-tPA alone. Although IV-tPA is a first line treatment for primary distal vessel occlusions, EVT is a feasible treatment for patients who have contraindication to IV-tPA.

Impact of time between thrombolysis and endovascular thrombectomy on outcomes in patients with acute ischaemic stroke.

Benefits of endovascular thrombectomy (ET) after intravenous thrombolysis (IVT) for patients with acute ischaemic stroke (AIS) have been demonstrated, but analyses of the relationship between IVT-ET time delay and functional outcomes among patients receiving both treatments are lacking. We used data from the "Berlin-Specific Acute Treatment in Ischaemic and haemorrhAgic stroke with Long-term outcome" (B-SPATIAL) registry. Between January 1st, 2016 and December 31st, 2019, we included patients who received both IVT and ET. The primary outcome was the 3-month ordinal modified Rankin scale (mRS) score. The IVT-ET time delay was analyzed in categories and continuously. We used adjusted ordinal logistic regression to estimate common odds ratios (cOR) and 95% confidence intervals (CI). Secondary analyses involved flexible modeling of IVT-ET delay and dichotomous outcomes. Of 11,049 patients, 714 who received IVT followed by ET were included. Compared with having an IVT-ET window >120 min (reference), for an IVT-ET window < 30 min, we obtained adjusted cORs for mRS of 0.41 (95% CI: 0.22 to 0.78); and 0.52 (95% CI: 0.33 to 0.82) for 30 to 120 min. Secondary analyses also found protective effects of shorter time delays against "poor" functional outcomes at 3 months. In patients with AIS, shorter IVT-ET intervals were associated with better 3-month functional outcomes. While the time-to-IVT and time-to-ET include the time until medical attention is received, the IVT-ET time delays fall entirely within the domain of medical management and thus might be easier to optimize.

Endovascular thrombectomy in acute ischemic stroke patients with prestroke disability (mRS ≥2): A systematic review and meta-analysis

ObjectiveThe effect of endovascular thrombectomy (EVT) in acute ischemic stroke patients with prestroke disability (modified Rankin Scale score, mRS) ≥2) has not been well-studied. This study aimed to assess the safety and benefit of EVT in patients with prestroke disability.MethodsAccording to PRISMA guidelines, literature searching was performed using PubMed, Embase, and Cochrane databases, for a series of acute ischemic stroke patients with prestroke mRS ≥2 treated by EVT. Random-effects meta-analysis was used to pool the rate of return to prestroke mRS and mortality at 3-month follow-up.ResultsIn total, 13 observational studies, with 2,625 patients, were analyzed. The rates of return to prestroke mRS in patients with prestroke mRS of 2–4 were 20% (120/588), 27% (218/827), and 31% (34/108), respectively. Patients with prestroke disability treated by EVT had a higher likelihood of return to prestroke mRS (relative risk, RR, 1.86; 95% CI 1.28–2.70) and a lower likelihood of mortality (RR 0.75; 95%CI 0.58–0.97) compared with patients with standard medical treatment. Successful recanalization (Thrombolysis in Cerebral Infarction grade 2b-3) after EVT gave a higher likelihood of return to prestroke mRS (RR 2.04; 95% CI 1.17–3.55) and lower mortality (RR 0.72; 95% CI 0.62–0.84) compared with unsuccessful reperfusion.ConclusionsAcute ischemic stroke patients with prestroke disability may benefit from EVT. Withholding EVT on the sole ground of prestroke disabilities may not be justified.Systematic Review Registration: https://www.crd.york.ac.uk/prospero/.

Association Between Use of a Flying Intervention Team vs Patient Interhospital Transfer and Time to Endovascular Thrombectomy Among Patients With Acute Ischemic Stroke in Nonurban Germany

The benefit of endovascular thrombectomy (EVT) for acute ischemic stroke is highly time-dependent, and it is challenging to expedite treatment for patients in remote areas. To determine whether deployment of a flying intervention team, compared with patient interhospital transfer, is associated with a shorter time to endovascular thrombectomy and improved clinical outcomes for patients with acute ischemic stroke. This was a nonrandomized controlled intervention study comparing 2 systems of care in alternating weeks. The study was conducted in a nonurban region in Germany including 13 primary telemedicine-assisted stroke centers within a telestroke network. A total of 157 patients with acute ischemic stroke for whom decision to pursue thrombectomy had been made and deployment of flying intervention team or patient interhospital transfer was initiated were enrolled between February 1, 2018, and October 24, 2019. The date of final follow-up was January 31, 2020. Deployment of a flying intervention team for EVT in a primary stroke center vs patient interhospital transfer for EVT to a referral center. The primary outcome was time delay from decision to pursue thrombectomy to start of the procedure in minutes. Secondary outcomes included functional outcome after 3 months, determined by the distribution of the modified Rankin Scale score (a disability score ranging from 0 [no deficit] to 6 [death]). Among the 157 patients included (median [IQR] age, 75 [66-80] y; 80 [51%] women), 72 received flying team care and 85 were transferred. EVT was performed in 60 patients (83%) in the flying team group vs 57 (67%) in the transfer group. Median (IQR) time from decision to pursue EVT to start of the procedure was 58 (51-71) minutes in the flying team group and 148 (124-177) minutes in the transfer group (difference, 90 minutes [95% CI, 75-103]; P < .001). There was no significant difference in modified Rankin Scale score after 3 months between patients in the flying team (n = 59) and transfer (n = 57) groups who received EVT (median [IQR] score, 3 [2-6] vs 3 [2-5]; adjusted common odds ratio for less disability, 1.91 [95% CI, 0.96-3.88]; P = .07). In a nonurban stroke network in Germany, deployment of a flying intervention team to local stroke centers, compared with patient interhospital transfer to referral centers, was significantly associated with shorter time to EVT for patients with acute ischemic stroke. The findings may support consideration of a flying intervention team for some stroke systems of care, although further research is needed to confirm long-term clinical outcomes and to understand applicability to other geographic settings.

Abstract TP147: Endovascular Therapy Versus Medical Therapy Alone For Basilar Artery Stroke: A Systematic Review And Meta-analysis Through Nested Knowledge

Background and Purpose: Endovascular thrombectomy (EVT) is an effective treatment for acute ischemic stroke (AIS) due to large vessel occlusion of the anterior circulation (AC-LVO). Randomized trials of posterior circulation large vessel occlusion (PC-LVO) patients have failed to show a benefit of EVT over medical therapy (MEDT). We performed a systematic review and meta-analysis to understand better whether EVT is beneficial for PC-LVO. Methods: Using the Nested Knowledge AutoLit living review platform, we identified randomized control trials and prospective studies that reported functional outcomes in patients with PC-LVO treated with EVT versus MEDT. The primary outcome variable was 90-day modified Rankin Scale (mRS) 0-3, and secondary outcome variables included 90-day mRS 0-2, 90-day mortality, and rate of symptomatic intracranial hemorrhage (sICH). A separate random effects model was fit for each outcome measure to calculate pooled odds ratios. Results: Three studies with 1,248 patients, 860 in the EVT arm and 388 in the MEDT arm, were included in the meta-analysis. The favorable outcome rate (mRS 0-3) in EVT patients was 39.9% (95% CI: 30.6-50.1%) versus 24.5% in MEDT patients (95% CI: 9.6-49.8%). EVT patients had higher mRS 0-2 rates (31.8% [95% CI: 25.7-38.5%] versus 19.7% [95% CI: 7.4-42.7%]) and lower mortality (42.1% [95% CI: 35.9-48.6%] versus 52.8% [95% CI: 33.3-71.5%]) compared to MEDT patients, but neither result was statistically significant. EVT patients were more likely to develop sICH (OR=10.36; 95% CI: 3.92-27.40). Conclusions: EVT treatment of PC-LVO trended toward superior functional outcomes and reduced mortality compared to MEDT despite a trend toward increased sICH in EVT patients. Existing randomized and prospective studies are insufficiently powered to demonstrate a benefit of EVT over MEDT in PC-LVO patients.

Endovascular Thrombectomy preceded by intravenous Alteplase versus endovascular Thrombectomy alone in Han Chinese patients treated for acute ischemic stroke with large vessel occlusion: a single-center retrospective analysis

BackgroundThe American Heart Association/ American Stroke Association and the Chinese Stroke Association guidelines are recommending intravenous alteplase intervention before endovascular thrombectomy if patients are eligible to do so but the benefits of endovascular thrombectomy are different in Chinese patients with stroke than those of the white patients. The objective of the study was to compare outcomes of patients with acute ischemic stroke treated with endovascular thrombectomy with intravenous alteplase against those treated with endovascular thrombectomy alone.MethodsA report is a retrospective analysis of comparing demographics, imaging, clinical and adverse outcomes in the Han Chinese patient who underwent mechanical thrombectomy for acute ischemic stroke with large vessel occlusion, with or without preceding intravenous alteplase administration. Patients with terminus and non-terminus intracranial occlusions and ≤ 2 points neurologic deficit underwent endovascular thrombectomy preceded by 0.9 mg/ kg intravenous alteplase (ET cohort, n = 184) and those who had contra-indication for intravenous alteplase were treated with endovascular thrombectomy alone (EA cohort, n = 141).ResultsThe most common procedural complications were embolization into new territory (p = 0.866) and uneventful artery vasospasm (p = 0.712). Insignificant differences were reported for any procedural complications (p = 0.991), imaging outcomes, the modified Rankin scale score (p = 0.663), and death (28 vs. 24, p = 0.761) within 90 days between patients of both cohorts. At the discharge of the hospital, the National Institutes of Health Stroke Scale scores of patients of the ET cohort were lower than those of the EA cohort (8.58 ± 3.79 vs. 10.23 ± 4.97, p = 0.003). The Barthel Index of survivors at 90 days after endovascular thrombectomy was higher for patients of the ET cohort than those of the EA cohort (87.47 ± 12.58 vs. 84.01 ± 13.47, p = 0.032). The most common adverse effect was asymptomatic intracranial hemorrhage (p = 0.297). Insignificant differences were reported for adverse effects after thrombectomy between survivors of both cohorts.ConclusionsOutcome measures in Han Chinese patients with acute ischemic stroke treated with endovascular thrombectomy alone were statistically the same as those treated with endovascular thrombectomy plus intravenous alteplase.Level of evidenceIiiTechnical efficacy stage4.

The Benefit of Endovascular Thrombectomy for Stroke on Functional Outcome Is Sustained at 12 Months

Background and Purpose: The short-term benefits of endovascular thrombectomy (EVT) for acute ischemic stroke (AIS) have been widely documented, yet there is limited evidence to show that this is sustained in the long term. We aimed to determine whether the benefit of EVT on functional outcome at 3 months is maintained at 12 months and the factors correlating with functional independence and quality of life. Methods: Data for analysis came from a prospective registry of consecutive patients undergoing EVT at a single Comprehensive Stroke Center (Oct 2018–Sep 2019). A phone interview was conducted for 12-month patient outcomes. Functional outcome was assessed by the modified Rankin Scale (mRS). Quality of life was determined by return to usual place of residence, work, or driving and calculation of a health utility index using the European Quality of Life-5 Dimensions questionnaire (EQ-5D-3L). Results: Of the 151 patients who underwent EVT during the study period, 12-month follow-up was available for 145 (96%). At 12 months, 44% (n = 64) of patients were functionally independent (mRS 0–2) compared to 48% at 3 months. Mortality at 12 months was 26% compared to 17% at 3 months. Significant predictors of functional independence at 12 months were younger age and lower baseline National Institutes of Health Stroke Scale. Better quality of life significantly correlated with return to usual place of residence and driving. Conclusion: Three-month functional independence was sustained at 12 months, indicating that EVT remains beneficial for patients with AIS in the longer term.

Healthy Life-Year Costs of Treatment Speed From Arrival to Endovascular Thrombectomy in Patients With Ischemic Stroke

The benefits of endovascular thrombectomy (EVT) are time dependent. Prior studies may have underestimated the time-benefit association because time of onset is imprecisely known. To assess the lifetime outcomes associated with speed of endovascular thrombectomy in patients with acute ischemic stroke due to large-vessel occlusion (LVO). PubMed was searched for randomized clinical trials of stent retriever thrombectomy devices vs medical therapy in patients with anterior circulation LVO within 12 hours of last known well time, and for which a peer-reviewed, complete primary results article was published by August 1, 2020. All randomized clinical trials of stent retriever thrombectomy devices vs medical therapy in patients with anterior circulation LVO within 12 hours of last known well time were included. Patient-level data regarding presenting clinical and imaging features and functional outcomes were pooled from the 7 retrieved randomized clinical trials of stent retriever thrombectomy devices (entirely or predominantly) vs medical therapy. All 7 identified trials published in a peer-reviewed journal (by August 1, 2020) contributed data. Detailed time metrics were collected including last known well-to-door (LKWTD) time; last known well/onset-to-puncture (LKWTP) time; last known well-to-reperfusion (LKWR) time; door-to-puncture (DTP) time; and door-to-reperfusion (DTR) time. Change in healthy life-years measured as disability-adjusted life-years (DALYs). DALYs were calculated as the sum of years of life lost (YLL) owing to premature mortality and years of healthy life lost because of disability (YLD). Disability weights were assigned using the utility-weighted modified Rankin Scale. Age-specific life expectancies without stroke were calculated from 2017 US National Vital Statistics. Among the 781 EVT-treated patients, 406 (52.0%) were early-treated (LKWTP ≤4 hours) and 375 (48.0%) were late-treated (LKWTP >4-12 hours). In early-treated patients, LKWTD was 188 minutes (interquartile range, 151.3-214.8 minutes) and DTP 105 minutes (interquartile range, 76-135 minutes). Among the 298 of 380 (78.4%) patients with substantial reperfusion, median DTR time was 145.0 minutes (interquartile range, 111.5-185.5 minutes). Care process delays were associated with worse clinical outcomes in LKW-to-intervention intervals in early-treated patients and in door-to-intervention intervals in early-treated and late-treated patients, and not associated with LKWTD intervals, eg, in early-treated patients, for each 10-minute delay, healthy life-years lost were DTP 1.8 months vs LKWTD 0.0 months; P < .001. Considering granular time increments, the amount of healthy life-time lost associated with each 1 second of delay was DTP 2.2 hours and DTR 2.4 hours. In this study, care delays were associated with loss of healthy life-years in patients with acute ischemic stroke treated with EVT, particularly in the postarrival time period. The finding that every 1 second of delay was associated with loss of 2.2 hours of healthy life may encourage continuous quality improvement in door-to-treatment times.

Which Acute Ischemic Stroke Patients Are Fast Progressors?: Results From the ESCAPE Trial Control Arm.

Fast infarct progression in acute ischemic stroke has a severe impact on patient prognosis and benefit of endovascular thrombectomy. In this post hoc analysis of the ESCAPE trial (Endovascular Treatment for Small Core and Proximal Occlusion Ischemic Stroke), we identified acute ischemic stroke patients with rapid infarct growth and investigated their baseline clinical and imaging characteristics. Control arm patients were included if they had follow-up imaging at 2-8 hours without substantial recanalization, and if their baseline Alberta Stroke Program Early CT Score was ≥9. Fast infarct progression was defined as Alberta Stroke Program Early CT Score decay ≥3 points from baseline to 2- to 8-hour follow-up imaging. Clinical and imaging baseline characteristics were compared between fast progressors and other patients, and occlusion site and collateral flow patterns were assessed in detail. Fast infarct progression occurred in 15 of 43 included patients (34.9%). Fast progressors had worse collaterals (poor in 3/15 [20%] versus 0/28 patients, P=0.021) and more carotid-T or -L occlusions (8/15 [53.4%] versus 3/28[10.7%], P=0.021). In 8 out of 15 (53.3%), occlusion site and circle of Willis configuration prevented collateral flow via the anterior or posterior cerebral artery. Most patients with fast infarct progression had terminal carotid occlusions and impaired collateral flow via the anterior or posterior cerebral artery, indicating that occlusion location and intracranial vascular anatomy are relevant for infarct progression.

Abstract 17: Time-Benefit Association is Magnified in Door-To-Puncture Window: Lose 1 Second, Lose 2.2 Hours of Healthy Life

Background: The benefits of endovascular thrombectomy (EVT) are time dependent. Prior studies may have underestimated the magnitude of the time-benefit relation because time of onset (last known well ”LKW”) is imprecisely known, and analyses including late-arriving patients have under-representation of “fast-progressors.” Methods: Patient level data were pooled by the HERMES Investigators from all 7 RCTs of stent retriever thrombectomy devices (entirely or predominantly) versus medical therapy. Analysis was confined to early-treated patients (LKW-to-puncture≤4h). Exposures: last known well-to-door (LKWTD) time; door-to-puncture (DTP) time; door-to-reperfusion (DTR) time. Outcomes: stroke-related quality of life at 3m (utility-weighted modified Rankin Scale); years of healthy life lost [disability-adjusted life years (DALYs)]. Results: Among the 781 EVT-treated patients, 406 (52.0%) were treated within 4h of LKW, with LKW-to-Door time median 188 minutes (IQR 151-215) and DTP time 105 minutes (IQR 76-135). Among the 295/372 (79.3%) with substantial reperfusion, DTR time was median 145 minutes (IQR 111-186). Care process delays were more strongly associated with worse clinical outcomes in the DTP and DTR epochs than the LKW-To-Door epoch (Table 1A), e.g., for each 10 minute delay, healthy life-years lost were: DTP 1.8 months vs LKW-to-Door 0.0 months, p &lt; 0.0001. Considering granular time increments, the amount of healthy life-years lost associated with each 1 second of delay was: DTP 2.2 hours, DTR 2.1 hours.(Table 1B) Conclusion: Post-arrival care delays are strongly associated with worse EVT patient outcomes in the early post-arrival time period. With every 1 second of delay in EVT delivery, patients lose 2.2 hours of healthy life-years. Continuous quality improvement to minimize delays in DTP and DTR for endovascular thrombectomy is warranted.

Risks and Benefits of Endovascular Thrombectomy in Older Adults

Endovascular thrombectomy (EVT) is an established treatment for patients with acute ischemic stroke and large vessel occlusion (LVO), but clinical