Crosa, Roberto

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.

Introduction: The outcomes of mechanical thrombectomy (MT) for patients with acute ischemic stroke (AIS) caused by medium vessel occlusions (MeVOs) in different vessels remains unknown. The aim of this study is to investigate MT outcomes in AIS patients with isolated MeVOs in different occluded vessel segments using the data from an ongoing international multicenter registry, the Stroke Thrombectomy and Aneurysm Registry (STAR). The aim of this study is to investigate MT outcomes in AIS patients with isolated MeVOs in different occluded vessel segments using the data from an ongoing international multicenter registry, the Stroke Thrombectomy and Aneurysm Registry (STAR). Methods: 110 AIS patients with MeVO who undertook MT between January 2010 and December 2022 were retrospectively investigated. MeVO was defined as isolated occlusion of the A2 or A3 (A23O) segment of the anterior cerebral artery, M3 segment of the middle cerebral artery (M3O), and P2 or P3 segment of the posterior cerebral artery (P23O). The primary outcome measure was a 90-day modified Rankin score (mRS) 0-2. The 90-day mRS 0-1, any intracranial hemorrhage, symptomatic intracranial hemorrhage, and 90-day mortality were used as secondary outcomes. Outcomes were compared between A23O, M3O, and P23O. Results: Median (interquartile range) age was 68.3 (58.4-76.0) years and 49 patients were female (46.7%). MeVO included 17 A23O (15.5%), 60 M3O (54.5%), and 33 P23O (30.0%).Compared to patients with A23O (17.7%), those with M3O (56.7%) and P23O (45.5%) had a higher proportion of 90-day mRS 0-2 (M3O, adjusted odds ratio 10.3, 95% confidence interval 1.71-62.2, p = 0.01; P23O adjusted odds ratio 8.86, 95% confidence interval 1.32-59.3, p =0.02). Other outcomes showed no significant differences. Conclusions: This study indicates A2O might be related to poorer outcomes compared to M3O and P23 in MT treatment for AIS patients due to isolated MeVO. Efforts should be aimed at improving outcomes following A23O to match those at other MeVO locations.

Background: Mechanical thrombectomy (MT) has significantly reduced morbidity and mortality in acute ischemic stroke (AIS). This study aims to analyze the outcomes and factors associated with decompressive hemicraniectomy (DHC) in AIS patients who underwent MT. Methods: We retrospectively analyzed data from an ongoing, multicenter database to investigate AIS patients who underwent MT for ICA, M1, or M2 occlusion. We compared clinical and procedural variables between patients who underwent DHC and those who did not. Propensity score (PS) matching between the two groups was conducted using age, sex, admission NIHSS, occluded vessel, ASPECTS, time from symptoms onset to arterial puncture, intracranial hemorrhage (ICH), and symptomatic ICH (sICH). Results: Among the 3,135 MT patients who met our inclusion criteria, 113 underwent DHC. A 1:3 propensity matching yielded a well-matched cohort of 113 in the DHC group versus 339 in the non-DHC group. The DHC group had a significantly higher rate of successful recanalization (mTICI ≥ 2C) (175 [51.6%] versus 36 [31.9%], P < 0.001) and a longer procedure duration, with a median of 30 minutes (IQR: 17-54) compared to 44 minutes (IQR: 25-78) in the non-DHC group (P = <0.001). Further comparison of patients with low ASPECTS (≤ 5) who underwent DHC (n = 36) with those who did not (n = 99) showed no significant difference in successful recanalization rates (15 [41.7%] versus 43 [43.4%], P > 0.90). However, procedure duration was significantly longer in the DHC group with a median of 29 minutes (IQR: 13-52), compared to 39 minutes (IQR: 27-86) in the non-DHC group (P = 0.02). Conclusions: Successful recanalization can help in preventing DHC in AIS patients with high ASPECTS, but not those with low ASPECTS. Procedure duration is independently related to DHC following MT, especially in low ASPECTS patients.

Introduction: The first-pass effect (FPE), defined as a complete or near-complete recanalization after a single pass of a mechanical thrombectomy (MT) device, has been linked to favorable clinical outcomes. However, its effectiveness in acute ischemic stroke (AIS) patients with low ASPECTS (Alberta Stroke Program Early CT Score 2-5) has not been validated. Method: We utilized data from STAR, a multicenter database of 84 centers worldwide, to conduct a retrospective, cohort study on patients who underwent MT for internal carotid artery (ICA) or M1 occlusion presenting with ASPECTS 2-5. We compared the outcomes of patients who achieved FPE (successful recanalization with an mTICI score of 2c or higher in one pass) to those who did not. The primary outcome was a 90-day favorable outcome, defined as mRS 0-3. Secondary outcomes included any intracranial hemorrhage (ICH), symptomatic ICH (sICH), and 90-day mortality. Results: Out of 10,229 patients in the STAR database, 250 patients met our inclusion criteria. Among those, 60 (24%) achieved FPE. There were no significant differences between the two groups in baseline, imaging, and procedural characteristics. FPE was significantly associated with higher odds of 90-day mRS 0-3 (adjusted odds ratio (aOR): 2.17, 95% confidence interval (CI): 1.04 - 4.20; P-value: 0.04) and lower rates of ICH (OR: 0.49, 95% CI: 0.25 - 0.93, P-value: 0.03). However, there was no significant difference in sICH rates (OR: 0.84, 95% CI: 0.31 - 2.04, P-value: 0.70). Conclusion: Achieving FPE in AIS stroke patients with low ASPECTS was associated with significantly higher rates of good functional outcomes and lower rates of ICH.

Introduction: Real-world data showed that less than half of the acute ischemic stroke (AIS) patients with large vessel occlusion (LVO) presenting with low Alberta Stroke Program Early Computed Tomography Score (ASPECTS) (2-5) achieved favorable outcomes at 90 days after mechanical thrombectomy (MT). In this study, we aim to investigate the relationship between the number of MT passes at which successful recanalization is obtained and outcomes in LVO-related AIS patients with low ASPECTS. Methods: This retrospective cohort study was performed on the data from 31 thrombectomy-capable centers between 2013 to 2022. Successful recanalization was defined as modified Thrombolysis in Cerebral Ischemia Score≥ 2b. The primary outcome was a 90-day modified Rankin Scale (mRS) of 0-3. Secondary outcomes were symptomatic intracranial hemorrhage and intracranial hemorrhage within 24 hours and mortality at 90 days. Outcomes were compared among patients with unsuccessful recanalization, and successful recanalization at first, second, third, and more than four passes. Results: A total of 297 patients with a median age of 70 [IQR 59-78] years were included and 140 (47.1%) were female. In 239 (80.4%) patients, successful recanalization was achieved: 88 patients (29.6 %) with 1 pass, 59 patients (19.9 %) with 2 passes, 35 patients(11.8%) with 3 passes, and 57 patients (19.2%) with more than 4 passes. Compared to unsuccessful recanalization, successful recanalization at first pass (adjusted OR 5.25, 95% CI 1.78 - 17.1), second passes (adjusted OR 5.20, 95% CI 1.68 - 17.6), and passes 4 (adjusted OR 4.90, 95% CI 1.68 - 17.6) was related to 90-day mRS 0-3. Recanalization status and MT attempt number were not related to secondary outcomes except for 90-day mortality. Compared to unsuccessful recanalization, successful recanalization at second and third passes were inversely related to 90-day mortality (adjusted OR 0.37, 95% CI 0.14 - 0.93; adjusted OR 0.33, 95% CI 0.11 - 0.95, respectively). Conclusion: The present results indicated that successful recanalization was related to 90-day good outcome regardless of the number of MT passes but the odds of achieving favorable outcome declines with each pass.

Introduction: The combination of intravenous or intra-arterial thrombolysis with mechanical thrombectomy (MT) for acute ischemic stroke (AIS) has been thoroughly investigated. However, no study has explored the outcomes of combining both intravenous and intra-arterial thrombolysis with MT. Methods: Data from Stroke Thrombectomy and Aneurysm Registry (STAR) from 2013 to 2023 was utilized. We compared AIS patients with LVO who underwent MT with combined intra-venous and intra-arterial thrombolysis (IV+IA) and with intra-venous thrombolysis alone (IV). We performed propensity score (PS) matching between the two groups using age, sex, premorbid mRS, admission NIHSS, occluded vessel, ASPECTS score, time from symptoms onset to arterial puncture, and frontline technique. Primary outcomes were any intracranial hemorrhage (ICH) and symptomatic ICH (sICH). Secondary outcomes included successful recanalization (mTICI ≥2C), early neurological improvement (defined as 4 or more points improvement in NIHSS score in 24 hours), 90-day modified Rankin Scale (mRS) 0-2, mRS 0-1, and mortality. Results: A total of 2495 LVO-related AIS patients were included, consisting of the IA+IV group (n = 266) and the IV group (n = 2228). Propensity matching yielded 192 well-matched patients in each group. No significant differences were observed between the groups in either ICH or sICH (odds ratio [OR]: 0.96, 95% confidence interval [CI]: 0.61-1.52, p = 0.60; OR: 0.92, 95% CI: 0.42-2.03, p > 0.90, respectively). The IA+IV group had a significantly lower proportion of successful recanalization (OR: 0.41, 95% CI: 0.27-0.62, p < 0.001), and early neurological improvement (OR: 0.55, 95% CI: 0.30-1.00). However, 90-day mRS 0-2, mRS 0-1, and mortality rates showed no significant differences between the two groups. Conclusion: The findings of this study suggest that the combined use of IA and IV thrombolysis in AIS patients undergoing MT is safe. Although the IA+IV group demonstrated lower rates of recanalization and early neurological improvement, long-term functional outcomes and mortality rates were comparable to the IV-thrombolysis group, indicating a potential delayed benefit of additional IA thrombolysis therapy.

Introduction: While balloon guide catheters (BGCs) enhance safety and efficacy of mechanical thrombectomy in large vessel occlusions, their impact on distal medium vessel occlusion (DMVO) remains underexplored. This study aimed to compare the outcomes of BGC vs non-BGC in DMVO thrombectomy. Methods: This retrospective study focused on DMVO cases defined as occlusions in M2-M4 middle cerebral artery, anterior cerebral artery, and posterior cerebral artery. Baseline characteristics and technical and clinical outcomes were compared between the two groups, with subgroup analysis in first-line thrombectomy techniques, including ADAPT, stent retriever, and Solumbra. First pass effect (FPE) was defined as a modified Thrombolysis in Cerebral Infarction (mTICI) score ≥ 2C after the first pass. Results: A total of 1,508 patients were included, of whom 231 (15.3%) were in the BGC group and 1,277 (84.7%) were in the Non-BGC group. The BGC group was associated with a lower mTICI score ≥ 2C (overall: 43.2% vs. 52.7%, p = 0.01; ADAPT: 42.2% vs. 57.1%, p = 0.01; Solumbra: 32.4% vs. 51.4%, p = 0.005), longer puncture to intracranial access time (overall: 15 vs. 8 min, p < 0.001; ADAPT: 17 vs. 8 min, p < 0.001; Solumbra: 12 vs. 8 min, p = 0.02), and longer puncture to recanalization time (overall: 97 vs. 35 min, p < 0.001; ADAPT: 100 vs. 28 min, p < 0.001; Solumbra: 78 vs. 46 min, p < 0.001; Stent retriever: 95 vs. 45 min, p < 0.001 ). The BGC group also had a lower FPE rate (17.4% vs. 30.7%, p = 0.03) in the Solumbra subgroup. In terms of clinical outcomes, the BGC group had a lower rate of distal embolization (overall: 8.8% vs. 14.9%, p = 0.02), but there were no significant differences in other clinical outcomes between the two groups in first-line thrombectomy techniques. Conclusions: Our findings showed that the use of BGC in DMVO had a lower mTICI score, reduced FPE rates, decreased distal embolization, and longer procedure times. Figure 1: Figure 2:

Introduction: The efficacy of mechanical thrombectomy (MT) for tandem vertebrobasilar occlusion (tVBO) is not well established in patients with basilar artery occlusion (BAO). Objective: To investigate the treatment outcomes of MT in tVBO. Method: This international, multicenter, retrospective cohort included patients with MT for tVBO and isolated BAO from 2013 to 2023. The primary outcome was the 90-day modified Rankin Scale (mRS) score 0-2. Secondary outcomes included complete recanalization (modified Thrombolysis in Cerebral Ischemia [mTICI] ≥ 2C) and 90-day mortality rate. These outcomes were compared between tVBO and isolated BAO groups. Adjustment factors were age, sex, admission National Institutes of Health Stroke Scale (NIHSS), pre-morbid mRS, onset to groin duration, and intravenous tissue plasminogen activator. Results: Among 10,229 patients, 689 had BAO. Of those, 61 (9.7%) had a tVBO. Median age was 61 [IQR 53-74] years and 29 (47.5%) patients were female. Compared to isolated BAO, tVBO group had lower age (61 [53-74] versus 68 [58-79], P<0.001) and lower admission NIHSS (15 [7 - 22] versus 17 [9-26], P≤0.05). There was no significant difference in the rate of complete recanalization between the two groups (adjusted odds ratio [aOR]: 0.83; 95% CI: 0.39-1.79; P=0.60) However, the tVBO group had significantly lower odds of a favorable outcome compared to the isolated BAO group (aOR: 0.35; 95% CI: 0.13-0.83; P=0.023) and higher odds of 90-day mortality (aOR: 3.51; 95% CI: 1.59-7.85; P=0.002). Binary regression analysis revealed that age (OR 0.98; 95% CI 0.96 - 1.00; P=0.019), admission NIHSS (OR 0.90; 95% CI 0.87-0.93; P<0.001), premorbid mRS (OR 0.71; 95% CI 0.53-0.93; P=0.016), successful recanalization (OR 2.94; 95% CI 1.71-5.15; P<0.001), and tVBO (OR 0.33; 95% CI 0.11-0.86; P=0.031) were significant predictors of 90-day favorable outcome. Conclusion: tVBO was associated with poor outcomes. Further efforts should be aimed at improving outcomes for this subpopulation.

Objective: To determine whether first pass effect (FPE) after mechanical thrombectomy (MT) for anterior circulation large vessel occlusion acute ischemic stroke (LVO-AIS) is modified by procedural time (PT). Methods: The Stroke Thrombectomy and Aneurysm Registry (STAR), a multi-center international dataset, was retrospectively analyzed for anterior circulation LVO-AIS treated by MT who achieved excellent reperfusion (TICI 2c/3). The primary outcome was good functional outcome as defined by a 90-day modified Rankin Scale (mRS) 0-2. The primary study exposure was first pass success (FPS, 1 pass vs ≥2 passes) and the secondary exposure was PT. Logistic regression models were fit-adjusted and marginal effects used to assess the interaction of PT (≤30 vs >30 minutes) and FPS, adjusting for potential confounders including time from last known well to start of MT. Results: A total of 1,310 patients had excellent reperfusion. These patients were divided into two 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=0.018). 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=0.001). However, there was no significant difference in the adjusted predicted probability of good outcome based on FPS in individuals with PT >30 minutes (p=0.763). This relationship appeared identical in models with PT treated as a continuous variable. Conclusion: In a large, real-world, multi-national dataset, we find that FPE is importantly modified by PT. The added clinical benefit of FPE is lost in longer procedures (>30 minutes). These data argue for a new metric for MT procedures, namely, FPE 30 , that better represents the ideal of fast, complete reperfusion with a single pass of a thrombectomy device.

Background As the number of thrombectomy passes increases during endovascular therapy (EVT) for acute stroke, neurointerventionalists must weigh the risks of potential complications against the risk of failing to recanalize the affected vessel. Thus, we investigated the effectiveness and safety of EVT for patients with acute stroke in which ≥5 EVT passes were performed. Methods This retrospective cohort study from January 2013 to December 2022 included 31 thrombectomy‐capable centers. Patients in whom ≥5 EVT passes were made were included in the analysis. The patients with successful recanalization defined as modified Thrombolysis in Cerebral Infarction ≥2b at 5, 6, 7, or more passes were compared with unsuccessful recanalization. We also compared procedure time, separated by 30 minutes. Primary outcome was a favorable 90‐day outcome (modified Rankin scale score of 0–2). Secondary outcomes were intracranial hemorrhage and death. Results A total of 407 patients met the inclusion criteria, of which 175 were women (43.1%); the mean age was 67.3 years. In 265 (65.1%) patients, successful recanalization was achieved: 134 patients with 5 passes, 67 patients with 6 passes, and 64 with ≥7 passes. Intravenous recombinant tissue plasminogen activator administration was more common in the unsuccessful recanalization group (successful recanalization with 5, 6, and ≥7 EVT passes and unsuccessful recanalization: 35.3%, 30.3%, 18.8%, and 45.4%, respectively). Successful recanalization with 5, 6, and ≥7 EVT passes was associated with favorable outcome compared with unsuccessful recanalization group (adjusted odds ratio successful recanalization with 5, 6, and ≥7 EVT passes to unsuccessful recanalization [95% CIs]: 8.29 [2.13–32.3]; 14.0 [3.27–60.3]; and 5.26 [1.12–24.8], respectively). However, symptomatic intracranial hemorrhage was not significantly different between the groups. Regarding procedure time, favorable outcome was not significantly different in each group, while symptomatic intracranial hemorrhage occurred more frequently in the 60 to 89 minutes group compared with the <30 minutes group (adjusted odds ratio, 60–89 minutes group to <30 minutes group [95% CI]: 5.86 [1.09–31.6]). Conclusion These findings suggest that a benefit in outcome persists for recanalization, without significant increase in complications. In addition, there was no significant difference in favorable outcomes among procedure time.