Starke, Robert M.

Background Multiple randomized trials could not establish the noninferiority of endovascular thrombectomy (EVT) alone without preceding intravenous thrombolysis (IVT) or superiority of IVT followed by EVT in anterior circulation large‐vessel occlusion stroke. The role of prior IVT in posterior circulation large‐vessel occlusion remains controversial. Methods In this multicenter, retrospective study, patients with stroke with large‐vessel occlusion in the posterior circulation who received EVT alone or with IVT were selected from the stroke thrombectomy and aneurysm registry between 2013 and 2022. Effects of IVT followed by thrombectomy on favorable functional outcome (defined as modified Rankin scale≤3 at 90 days) and safety were investigated using multivariable logistic and linear regression models. Results Of the 588 included patients, 67% (n = 394) were treated with EVT alone and 29% (n = 170) with EVT after IVT, and 4% (n = 24) have missing values on this variable. Controlling for multiple confounding factors, IVT was not associated with a higher likelihood of favorable functional outcome at 90 days (odds ratio, 1.04 [95% CI, 0.52–2.09; P = 0.901). Thrombectomy alone did not show any safety advantages compared with those receiving IVT. Conclusion Similar functional outcomes and complication rates were seen in patients with posterior circulation large‐vessel occlusion treated with EVT alone versus EVT after IVT. Further prospective studies are required to determine the utility of IVT in posterior circulation stroke, especially in patients being directly admitted to thrombectomy centers.

OBJECTIVE The placement of flow-diverting devices has become a common method of treating unruptured intracranial aneurysms of the internal carotid artery. The progressive improvement of aneurysm occlusion after treatment—with low complication and rupture rates—has led to a dilemma regarding the management of aneurysms in which occlusion has not occurred within 6–24 months. The authors aimed to identify clinical consensus regarding management of intracranial aneurysms displaying persistent filling 6–24 months after flow diversion and to ascertain questions that may drive future investigation. METHODS An international panel of 67 experts was invited to participate in a multistep Delphi consensus process on the treatment of intracranial aneurysms after failed flow diversion. RESULTS Of the 67 experts invited, 23 (34%) participated. Qualitative analysis of an initial survey with open-ended questions resulted in 51 statements regarding management of aneurysms showing persistent filling after flow diversion. The statements were grouped into 8 categories, and in the second round, respondents rated the degree of their agreement with each statement on a 5-point Likert scale. Flow diverters with surface modifiers did not influence administration of dual-antiplatelet therapy according to 83%. Consensus was also reached regarding the definition of treatment failure at specific time points, including at 6 months if there is aneurysm growth or persistent rapid flow through the entirety of the aneurysm (96%), at 12 months if there is aneurysm growth or symptom onset (78%), and at 24 months if there is persistent filling regardless of size and filling characteristics (74%). Although experts agreed that the degree of intimal hyperplasia or in-device stenosis could not be ascertained by noninvasive imaging alone (83%), only 65% chose digital subtraction angiography as the preferred modality. At 6 and 12 months, retreatment is preferred if there is persistent filling with aneurysm growth (96%, 96%), device malposition (48%, 87%), or a history of subarachnoid hemorrhage (65%, 70%), respectively, and at 24 months if there is persistent filling without reduction in aneurysm size (74%). Experts favored treatment with an additional flow diverter (87%) over aneurysm clipping, applying the same principles for follow-up (83%) and treatment failure (91%) as for the first flow diverter. CONCLUSIONS The authors present the consensus practices of experts in the management of intracranial aneurysms without occlusion 6–24 months after treatment with a flow-diverting device.

BACKGROUND AND OBJECTIVES: This study aimed to compare outcomes of low Alberta Stroke Program Early Computed Tomography Score (ASPECTS) patients with stroke who underwent mechanical thrombectomy (MT) within 6 hours or 6 to 24 hours after stroke onset. METHODS: A retrospective cohort study was conducted using data from a large multicenter international registry from 2013 to 2023. Patients with low ASPECTS (2-5) who underwent MT for anterior circulation intracranial large vessel occlusion were included. A propensity matching analysis was conducted for patients presented in the early (<6 hours) vs late (6-24 hours) time window after symptom onset or last known normal. RESULTS: Among the 10 229 patients who underwent MT, 274 met the inclusion criteria. 122 (44.5%) patients were treated in the late window. Early window patients were older (median age, 74 years [IQR, 63-80] vs 66.5 years [IQR, 54-77]; P < .001), had lower proportion of female patients (40.1% vs 54.1%; P = .029), higher median admission National Institutes of Health Stroke Scale score (20 [IQR, 16-24] vs 19 [IQR, 14-22]; P = .004), and a higher prevalence of atrial fibrillation (46.1% vs 27.3; P = .002). Propensity matching yielded a well-matched cohort of 84 patients in each group. Comparing the matched cohorts showed there was no significant difference in acceptable outcomes at 90 days between the 2 groups (odds ratio = 0.90 [95% CI = 0.47-1.71]; P = .70). However, the rate of symptomatic ICH was significantly higher in the early window group compared with the late window group (odds ratio = 2.44 [95% CI = 1.06-6.02]; P = .04). CONCLUSION: Among patients with anterior circulation large vessel occlusion and low ASPECTS, MT seems to provide a similar benefit to functional outcome for patients presenting <6 hours or 6 to 24 hours after onset.

OBJECTIVE This study was conducted to investigate the impact of antiplatelet administration in the periprocedural period on the occurrence of thromboembolic complications (TECs) in patients undergoing treatment using the Woven EndoBridge (WEB) device for intracranial wide-necked bifurcation aneurysms. The primary objective was to assess whether the use of antiplatelets in the pre- and postprocedural phases reduces the likelihood of developing TECs, considering various covariates. METHODS A retrospective multicenter observational study was conducted within the WorldWideWEB Consortium and comprised 38 academic centers with endovascular treatment capabilities. Univariable and multivariable logistic regression analyses were performed to determine the association between antiplatelet use and TECs, adjusting for covariates. Missing predictor data were addressed using multiple imputation. RESULTS The study comprised two cohorts: one addressing general thromboembolic events and consisting of 1412 patients, among whom 103 experienced TECs, and another focusing on symptomatic thromboembolic events and comprising 1395 patients, of whom 50 experienced symptomatic TECs. Preprocedural antiplatelet use was associated with a reduced likelihood of overall TECs (OR 0.32, 95% CI 0.19–0.53, p < 0.001) and symptomatic TECs (OR 0.49, 95% CI 0.25–0.95, p = 0.036), whereas postprocedural antiplatelet use showed no significant association with TECs. The study also revealed additional predictors of TECs, including stent use (overall: OR 4.96, 95% CI 2.38–10.3, p < 0.001; symptomatic: OR 3.24, 95% CI 1.26–8.36, p = 0.015), WEB single-layer sphere (SLS) type (overall: OR 0.18, 95% CI 0.04–0.74, p = 0.017), and posterior circulation aneurysm location (symptomatic: OR 18.43, 95% CI 1.48–230, p = 0.024). CONCLUSIONS The findings of this study suggest that the preprocedural administration of antiplatelets is associated with a reduced likelihood of TECs in patients undergoing treatment with the WEB device for wide-necked bifurcation aneurysms. However, postprocedural antiplatelet use did not show a significant impact on TEC occurrence.

BACKGROUND AND OBJECTIVES: First pass effect (FPE) is a metric increasingly used to determine the success of mechanical thrombectomy (MT) procedures. However, few studies have investigated whether the duration of the procedure can modify the clinical benefit of FPE. We sought to determine whether FPE after MT for anterior circulation large vessel occlusion acute ischemic stroke is modified by procedural time (PT). METHODS: A multicenter, international data set was retrospectively analyzed for anterior circulation large vessel occlusion acute ischemic stroke treated by MT who achieved excellent reperfusion (thrombolysis in cerebral infarction 2c/3). The primary outcome was good functional outcome defined by 90-day modified Rankin scale scores of 0–2. The primary study exposure was first pass success (FPS, 1 pass vs ≥2 passes) and the secondary exposure was PT. We fit-adjusted logistic regression models and used marginal effects to assess the interaction between PT (≤30 vs >30 minutes) and FPS, adjusting for potential confounders including time from stroke presentation. RESULTS: A total of 1310 patients had excellent reperfusion. These patients were divided into 2 cohorts based on PT: ≤30 minutes (777 patients, 59.3%) and >30 minutes (533 patients, 40.7%). Good functional outcome was observed in 658 patients (50.2%). The interaction term between FPS and PT was significant ( P = .018). Individuals with FPS in ≤30 minutes had 11.5% higher adjusted predicted probability of good outcome compared with those who required ≥2 passes (58.2% vs 46.7%, P = .001). However, there was no significant difference in the adjusted predicted probability of good outcome in individuals with PT >30 minutes. This relationship appeared identical in models with PT treated as a continuous variable. CONCLUSION: FPE is modified by PT, with the added clinical benefit lost in longer procedures greater than 30 minutes. A comprehensive metric for MT procedures, namely, FPE 30 , may better represent the ideal of fast, complete reperfusion with a single pass of a thrombectomy device.

Introduction: Acute ischemic stroke (AIS) patients often require multiple passes during mechanical thrombectomy (MT) to open the vessel. Yet, at times, even numerous passes are unsuccessful. This study aims to investigate the impact of the number of passes on the outcomes of patients who underwent failed MT. Methods: We used Data from the Stroke Thrombectomy and Aneurysm Registry (STAR) from 2013 to August 2023. Patients who underwent MT for ICA, M1, or M2 with unsuccessful recanalization (modified Thrombolysis in Cerebral Infarction ≤ 2a) were included. Primary outcome was 90- day modified Rankin Scale (mRS) 0-2. Secondary outcomes included any intracranial hemorrhage (ICH) and symptomatic ICH (sICH). Outcomes were compared among patients who received ≤ 2, 3, 4, and ≥ 5 MT passes. Results: 736 patients met inclusion criteria. 90-day mRS 0-2 was found to decrease with number of passes (Figure 1). Multivariate logistic regression analysis revealed that 3 passes (OR: 0.48, 95% CI: 0.23 -0.96, P-value: 0.04), 4 passes (OR: 0.46, 95% CI: 0.19 -1.03, P-value: 0.07), and ≥ 5 passes (OR: 0.22, 95% CI: 0.08 -0.50, P-value: <0.001) were associated with lower odds of mRS 0-2 compared to ≤ 2 passes. However, there were no significant differences between groups in ICH, sICH, or 90-day mortality. Conclusion: The number of passes affects functional outcomes among stroke patients who underwent failed MT.

Introduction: Recent randomized control trials suggested that mechanical thrombectomy (MT) was associated with good functional outcomes after acute ischemic stroke (AIS) due to large vessel occlusion (LVO) in patients presenting with low Alberta Stroke Program Early CT Score (ASPECTS) (defined as ASPECTS 2-5). The aim of this study is to develop and validate a stroke prediction tool for outcome in MT for AIS patients with low ASPECTS using data from an ongoing international multicenter registry, the Stroke Thrombectomy and Aneurysm Registry (STAR). Methods: 236 AIS patients with low ASPECTS caused by LVO who undertook MT between January 2010 and December 2022 were retrospectively investigated. Univariate and multivariate logistic regression results were used to screen model predictors and construct nomograms of 90-day modified Rankin Scale scores (mRS) 0-3. The performance of the model was detected by using receiver operating characteristic analysis. The bootstrap resampling method was considered internal validation of the model. Results: Age (< 70 years), premorbid status (mRS 0), National Institutes of Health Stroke Scale (NIHSS) (< 20), and recanalization status after the MT (modified Thrombolysis in Cerebral Ischemia [mTICU] ≥2b) were related to 90-day mRS 0-3. Predictive score was calculated by adding 1 point for age (< 70 years), premorbid status (mRS 0), and NIHSS < 20 and 3 points for a mTICI ≥2b (ranging 0-6). 90-day mRS 0-3 was observed in 0% of patients with a score of 0 or 1, 6.3% with a score of 2, 17.7% with a score of 3, 22.2% with a score of 4, 45.7% with a score of 5, and 73.7% with a score of 6. The score showed relatively high performance in predicting 90-day mRS0-3 (area under the curve: 0.79 [95% CI 0.73-0.79] and 0.78 [95% CI 0.78-0.78] for derivation and validation cohorts, respectively). Conclusions: This study indicates the STAR score can be calculated with baseline and periprocedural characteristics to predict the 90-day outcome after MT in AIS patients with low ASPECTS.

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.

Introduction: The benefits of intravenous thrombolysis (IVT) in acute ischemic stroke (AIS) patients with unsuccessful mechanical thrombectomy (MT) are not well established. Methods: This study included patients from the Stroke Thrombectomy and Aneurysm Registry (STAR) who underwent MT for ICA, M1, or M2 occlusions with unsuccessful MT (mTICI score ≤ 2a). Patients who received IVT prior to MT were compared to those who received MT alone. Propensity score (PS) matching was performed using age, sex, premorbid modified Rankin Scale (mRS), admission National Institute of Health Stroke Scale (NIHSS), occluded vessel, ASPECTS score, mTICI score, and symptom onset to groin puncture time. The primary outcome was favorable 90-day outcomes (mRS 0-2). Results: Of 610 patients with unsuccessful MT, 219 were matched in each group. Median ages were 70 [IQR: 61 - 80] and 73 [IQR: 62 - 81] in the IVT + MT and MT alone groups, respectively. In the IVT + MT group. Final TICI scores of 0, 1, and 2a were achieved in 92 (42.0%), 33 (15.1%), and 94 (42.9%) patients, respectively, compared to 76 (34.7%), 29 (13.2%), and 114 (52.1%) in the MT alone group. The IVT + MT group showed a significantly. higher 90-day mRS of 0-2 (aOR: 2.54, 95% CI: 1.53-4.32) and mRS of 0-3 (aOR: 2.05, 95% CI: 1.36-3.12). There were no significant differences between the groups in intracranial hemorrhage (ICH), symptomatic ICH, or 90-day mortality rates. Conclusions: IVT is associated with improved functional outcomes in patients with unsuccessful MT. Ensuring that IVT is provided to all eligible stroke patients should remain a priority.

Introduction: Up to 50% of acute ischemic stroke (AIS) patients who undergo successful mechanical thrombectomy (MT) fail to achieve favorable outcomes (futile recanalization). In this study we aim to develop a machine learning (ML) model to predict futile recanalization (FR) in AIS patients who undergo MT. Methods: We used data from an ongoing large, multicenter database from 2013 to 2023. We included AIS patients treated with MT for ICA, M1, or M2 occlusion with successful recanalization (modified Thrombolysis in Cerebral Infarction [mTICI] score ≥ 2C) and procedure durations under 60 minutes. FR was defined as successful recanalization with 90-day modified Rankin Scale (mRS) 3-6. The dataset was divided into 75% for training and 25% for external validation. Using the Caret Package in R, multiple models were tested, and their performances were evaluated by the area under the curve (AUC) of receiver operating. Both baseline and pre-interventional characteristics were incorporated into the model. The selected model was then externally validated on a 25% validation dataset. Results: Among 2,546 qualified patients, FR occurred in 1,342 (52.7%). In univariate analysis, baseline characteristics were significantly different between FR and non-FR groups. The M5P model demonstrated the highest performance (AUC: 0.833; 95% CI: 0.7989-0.852; PPV: 0.8101) in comparison to other tested models such as logistic regression (AUC: 0.74), RF (AUC: 0.78), J48 (AUC: 0.78), SVM (AUC: 0.79), and GB (AUC: 0.79). The external validation of the model showed satisfactory results (AUC: 75.25; 95% CI: 70-80; PPV: 76.87). Conclusion: Utilizing clinical, pre-procedural, and imaging parameters, the M5P model can efficiently predict F) in AIS patients before attempting MT. This tool can assist neurointerventionalists in adequately choosing their MT candidates.