Spiotta, Alejandro M

Background Randomized trials have shown equivocal outcomes between a direct aspiration as first-pass technique (ADAPT) and stent retriever (SR) stroke thrombectomy, yet whether specific patient subgroups benefit differentially from one technique over the other remains unknown. Methods In this retrospective multicenter cohort study, patients with large vessel occlusion were included, and those who underwent ADAPT versus SR first-pass thrombectomy (either as standalone or combined with aspiration) were compared. The primary outcome was a composite of first-pass effect (FPE, modified Thrombolysis In Cerebral Infarction (mTICI) 2c or better with one attempt) with no symptomatic intracranial hemorrhage (sICH). A causal forest model was used to estimate the conditional average treatment effect (CATE) for each patient, with larger CATEs indicating that ADAPT is expected to be more advantageous. Patients were stratified by CATEs, and outcomes were compared between treatment groups. Results Among 6700 included patients, ADAPT (n=3695, 55%) was associated with a higher rate of FPE with no sICH (39.9% vs 26.9%; adjusted OR (aOR) 2.07, 95% CI 1.77 to 2.41, P<0.001). The causal forest identified significant treatment effect heterogeneity (interaction P<0.001), where ADAPT was more advantageous in more recent years and among patients with M1 occlusions presenting in earlier time windows. Low-CATE patients showed no statistically significant difference between techniques (aOR 0.91, 95% CI 0.57 to 1.45, P=0.70), while medium- and high-CATE patients demonstrated progressively larger ADAPT advantages (aOR 2.06, 95% CI 1.67 to 2.55, and aOR 2.99, 95% CI 2.24 to 3.98, respectively, both P<0.001). Conclusions ADAPT may be superior to SR for a majority of patients, particularly in recent years, and among patients with M1 occlusions presenting in earlier time windows.

OBJECTIVE Endovascular thrombectomy (EVT) for acute large-vessel occlusion stroke is well established, yet its role in patients presenting with minor stroke symptoms (National Institutes of Health Stroke Scale [NIHSS] score < 6) remains unclear. Prior studies have not accounted for intraprocedural factors that may influence outcomes in this subgroup. METHODS The authors analyzed 5693 patients from the STAR (Stroke and Thrombectomy and Aneurysm Registry), including 398 with low NIHSS scores, to evaluate the association between procedure time (PT) and outcomes. Among patients with low NIHSS scores, propensity score matching was used to compare outcomes between those with PT ≤ 35 versus > 35 minutes, a cutoff defined using receiver operating characteristic curve analysis. The authors performed a meta-analysis of studies reporting best medical management (BMM) outcomes in patients with low NIHSS scores. To compare these with EVT-treated patients, a matched BMM comparator cohort using stratification on pooled baseline characteristics was constructed. Outcomes included 90-day functional independence (modified Rankin Scale [mRS] scores 0–2), intracranial hemorrhage, and mortality. RESULTS PT had a stronger negative effect on outcomes in patients with low NIHSS scores compared with those with high scores, with a steeper decline in functional independence per minute of PT (slope: –0.45% vs –0.21%; p = 0.03 for interaction). Among patients with low scores, PT ≤ 35 minutes was associated with higher 90-day functional independence compared with the propensity score–matching cohort with PT > 35 minutes (82.6% vs 59.0%, p < 0.001). When benchmarked against BMM (75.2% mRS scores 0–2), patients undergoing EVT within 35 minutes had superior outcomes (85.1%, p = 0.047). In contrast, EVT with PT > 35 minutes resulted in worse outcomes than BMM (mRS scores 0–2: 59.8%, p = 0.008). The number needed to treat for PT ≤ 35 minutes was 10, whereas PT > 35 minutes yielded a number needed to harm of 6. CONCLUSIONS PT critically modulates the benefit of EVT in minor stroke. While efficient EVT yields better outcomes than BMM, prolonged procedures are associated with harm. These findings may explain prior inconsistent evidence on EVT in patients with low NIHSS scores and underscore the need to individualize procedural thresholds in this population.

OBJECTIVE The objective was to evaluate the trajectories of hematoma resolution and functional improvement after middle meningeal artery embolization (MMAE) for chronic subdural hematoma (cSDH), model the temporal pattern of cSDH resolution, and identify factors associated with favorable outcomes. METHODS This real-world multicenter retrospective study included cSDH patients treated with MMAE at 24 centers between 2019 and 2024. Hematoma thickness was measured at baseline and at follow-up intervals (1–4 weeks, 1–3 months, 3–6 months, 6–12 months, and > 12 months after embolization). Resolution patterns were modeled using exponential decay functions. Modified Rankin Scale (mRS) scores assessed functional outcomes. Good functional outcome was defined as mRS score ≤ 2. Resolution patterns were modeled using exponential decay functions to estimate time to 50% and 80% reduction. Patients were categorized as complete resolution (≥ 99%) or by quartile of the remaining distribution (substantial [73%–98%], moderate [53%–73%], partial [27%–53%], minimal [< 27%]). The primary outcome was good functional status (mRS score ≤ 2). RESULTS The authors analyzed a total of 1781 patients with 2295 cSDHs who underwent MMAE. The mean ± SD age was 72.8 ± 12.4 years and 68.1% of patients were male. The initial mean hematoma thickness was 15.31 ± 6.53 mm, decreasing to 5.24 ± 5.91 mm at final follow-up (mean reduction 64.3% ± 42.1%). Resolution followed an exponential decay pattern, with an estimated time to 50% reduction of 1.8 months and to 80% reduction of 8.9 months. Complete resolution occurred in 1031 of 2224 patients (46.4%) with complete follow-up. The median (IQR) mRS score improved from 1 (0–3) at baseline to 0 (0–2) at > 12 months. Good functional outcomes were more common in patients with complete versus minimal resolution (68.9% vs 35.0%, p < 0.001). Achieving ≥ 73% resolution within 90 days was associated with better outcomes (good outcome in 76.9% of those with ≥ 73% resolution vs 67.3% in those without, p < 0.001). Neurological deterioration was the strongest predictor of lack of good outcome (23.7% in patients with neurological deterioration vs 82.4% without, p < 0.001). CONCLUSIONS After MMAE for cSDH, reduction in hematoma thickness follows a predictable exponential decay pattern. Greater extent (≥ 80%) and faster timing (within 90 days) of resolution are valuable prognostic indicators. Functional outcomes improve progressively through 6–12 months after the procedure. The relationship between resolution extent and functional outcomes provides quantitative benchmarks for evaluating treatment response.

Abstract Background Recent trials have furthered uncertainty regarding the endovascular benefit for medium vessel occlusions (MeVO). Stent retrievers (SR) were employed in the first attempt in most interventional arm participants. We sought to compare outcomes in acute MCA M2 occlusions between frontline aspiration and SR, and to delineate procedural and anatomical covariates associated with differential treatment effect. Methods Retrospective analysis of a multicenter stroke thrombectomy cohort identified cases of MT for M2 occlusions. Unmatched and propensity score-matched (PSM) cohorts were generated comparing frontline aspiration to standalone and combined SR. The primary outcome was functional independence (mRS 0–2) at 90 days. Recanalization, symptomatic intracranial hemorrhage (sICH), mortality, and the effect of M2 laterality, division occlusion and procedure time were assessed. Results About 1734 patients with M2 occlusions underwent either frontline aspiration (n = 711) or SR/combined (n = 958) thrombectomy between 2013 and 2024. PSM analysis favored aspiration for functional independence (49.9% vs 44.0%, OR 1.27 (1.03–1.57)), complete recanalization (61.2% vs 48.7%, OR 1.66 (1.34–2.05)), complete first pass effect (35.0% vs 27.6%, OR 1.42 (1.13–1.78)), and sICH (3.5% vs 6.2%, OR 0.55 (0.33–0.91)), with no difference in mortality. Frontline aspiration had significantly shorter procedural times (median 28 [IQR 15–49.5] vs 51 [IQR 35–78] minutes; p &lt; 0.001). For every minute increase in procedure time, the probability of functional independence decreased significantly (p &lt; 0.001) less with frontline aspiration (0.35%) compared to SR/combined (1.61%). Conclusion Frontline aspiration for M2 occlusions resulted in better clinical and angiographic outcomes compared to SRs. Future trials for MeVO with a focus on contact aspiration thrombectomy may succeed where recent trials have failed.

Background Contact aspiration remains a frontline approach for mechanical thrombectomy (MT) in acute ischemic stroke (AIS). Early evidence correlates catheter size with procedural efficiency and clinical outcomes. Larger‐bore (LB) aspiration catheters may enhance clot ingestion, increase aspiration force, and facilitate faster and more complete recanalization. However, the transition from standard LB catheters (0.068‐0.072″) to super‐large‐bore (SLB, ≥0.080″) devices has raised questions regarding both safety and clinical benefit. Although the use of SLB catheters is increasing, comparative data on their performance versus LB catheters remain limited. This study aims to evaluate the safety and efficacy of SLB compared with LB catheters including data from a large multicenter international registry. Methods We retrospectively analyzed patients with AIS due to LVO treated at 46 international stroke centers between January 2013 and June 2025. Among eligible patients, propensity score matching (PSM) at a 5:1 ratio was used to balance baseline characteristics between those treated with standard LB catheters and those treated with SLB catheters. Safety endpoints included intraprocedural complications, symptomatic intracranial hemorrhage (sICH), distal embolization, and 90‐day mortality. Efficacy endpoints included functional independence at 90 days (modified Rankin Scale [mRS] 0‐2), successful recanalization (TICI ≥2b), first‐pass effect (TICI ≥2b on the first aspiration attempt), and procedural timing to TICI2b. Results A total of 3,100 patients were included (LB n=3,024; SLB n=67). After PSM (LB n=335; SLB n=67), safety outcomes were comparable between groups in terms of intraprocedural complications occurred (p=0.5), sICH (p>0.9), embolization to new territory (p=0.2), and 90‐day mortality (p>0.9). Efficacy outcomes were similarly consistent for functional independence (mRS 0‐2) (p>0.9), successful recanalization (p>0.9), first‐pass effect (p=0.5), and time to TICI ≥2b (27.6 vs. 24.5 minutes; p=0.9). These findings remained consistent in the subgroup with ICA and M1 occlusions, with no significant differences in safety (intraprocedural complications [p=0.4], sICH [p>0.9], embolization to new territory [p=0.6], or 90‐day mortality [p>0.9], nor in efficacy outcomes (functional independence at 90 days [p>0.9], successful recanalization [p=0.9], first‐pass effect [p=0.6], and time to TICI ≥2b [p=0.9]). Conclusion In this large multicenter analysis, the use of SLB aspiration catheters demonstrated comparable safety and efficacy to standard LB catheters for MT in AIS. Despite theoretical advantages in aspiration dynamics, SLB devices did not confer significant procedural or clinical benefit over LB catheters. These findings suggest that while SLB catheters are a feasible alternative, technical and clinical outcomes remain comparable to LB catheters. Further prospective studies are warranted to clarify potential clinical advantages. image

Background Endovascular thrombectomy (EVT) has transformed acute ischemic stroke (AIS) care, with onset-to-puncture (OTP) time widely recognized as a critical determinant of outcome. However, emerging evidence suggests that in-hospital procedure time (PT)—from arterial puncture to final recanalization—may have an equally or more significant impact. This study examines the relative contribution of PT versus OTP to functional outcomes in patients with AIS undergoing EVT. Methods A retrospective analysis was conducted of 6644 patients with AIS treated at 44 international stroke centers from the Stroke Thrombectomy and Aneurysm Registry (STAR; 2016–2023). Multivariable regression, time-equivalence analysis, and marginal effects modeling were used to assess associations between PT, OTP, and 90-day modified Rankin Scale (mRS) outcomes. Centers were stratified by procedural efficiency and compared using propensity score matching (PSM). Mediation analysis evaluated whether PT accounted for inter-center differences. Results PT and OTP were independently associated with functional outcomes; however, PT had a significantly stronger effect (adjusted OR for mRS 0–2: PT=0.56 vs OTP=0.96 per hour). Each 5 min increase in PT was equivalent to 78–100 min of additional OTP in outcome impact. Centers with faster average PT had higher rates of functional independence (number needed to treat (NNT)=10), fewer complications, and lower symptomatic intracranial hemorrhage rates. PT significantly mediated the relationship between center tier and outcomes (Sobel’s P<0.001). Conclusion While minimizing OTP remains important, PT exerts a greater influence on outcomes after EVT. Procedural efficiency should be emphasized in stroke systems of care and included in center performance metrics to improve patient outcomes.

BACKGROUND AND OBJECTIVES: Flow-diverting stents (FDSs) have improved treatment options for intracranial aneurysms. Although FDS have proven successful in treating aneurysms that would previously have required complex microsurgical or endovascular repairs, treatment failures remain a concern. In this multicenter study, we aim to analyze the predictors of residual aneurysmal filling at early angiographic follow-up. METHODS: A retrospective analysis of a prospectively maintained neuroendovascular database at 14 high-volume US centers was conducted for all patients who underwent FDS placement for intracranial aneurysms between 2011 and 2019. Aneurysms were graded on the O'Kelly-Marotta scale (OKM). RESULTS: A total of 2277 patients underwent FDS embolization for intracranial aneurysms during the study period. The patient's mean age was 55 (SD ± 13.5) years, and 82% were female. The median maximal aneurysm diameter was 6.7 mm (IQR 4.10-11 mm). Complete aneurysm obliteration (OKM grade 4) occurred in 1109 patients (68%), and 146 (9%) were OKM grade 3, 188 (12%) were OKM grade 2, and 174 (11%) were OKM grade 1. In the adjusted multivariate analysis, individuals in the 65-74 years and 75+ years age groups had significantly increased risk of residual aneurysm filling at 6-month follow-up compared with the 18-44 years age group (odds ratio [OR] 1.92 (95% CI: 1.33-2.78) and 2.92 (95% CI: 1.79-4.77), respectively). Aneurysms arising from the superior cerebellar artery, the basilar artery, and the carotid terminus were more likely to have a residual filling (OR 12.6, 95% CI: 1.39–14.7; OR 4.27, 95% CI: 1.39–14.7; OR 3.16, 95% CI: 1.24–8.06, respectively). CONCLUSION: As the utilization of FDS for intracranial aneurysms becomes more widespread, the efficacy of aneurysm obliteration needs to be assessed. Our results indicate that several patient-dependent factors, such as age, aneurysm location, and size, predict the likelihood of residual aneurysm filling 6 months post-treatment.

Introduction: Endovascular thrombectomy (EVT) is an effective treatment for basilar artery occlusion (BAO) stroke in select patients. While there is a growing body of literature suggesting that advanced imaging modalities such as computed tomography perfusion (CTP) and magnetic resonance (MR) may not be necessary for selecting anterior circulation large vessel occlusion stroke patients for EVT, whether advanced imaging may be superior to conventional imaging (non-contrast CT and CT angiography) in identifying good treatment candidates among BAO patients is less clear. Patients and methods: This was a multicenter retrospective cohort study of BAO EVT patients treated from 2013 to 2022 in the Stroke Thrombectomy and Aneurysm Registry. Patients selected for EVT by advanced imaging (CTP or MR) were matched with those selected by conventional imaging using propensity score matching (PSM) accounting for possible confounders. Primary outcome was functional independence at 90 days. Other outcomes include bedridden state or death at 90-days and symptomatic intracranial hemorrhage (sICH). Results: 268 patients were included. 150 patients were selected for BAO EVT by conventional imaging, 86 by CTP, and 32 by MR. Patients selected by advanced imaging were significantly older than those selected by conventional imaging (median age 71 vs 64 years, p = 0.001); patient characteristics were otherwise similar between cohorts. After PSM, 90-day outcomes were similar between the two cohorts ( p = 0.56), with similar rates of functional independence (39.4% vs 35.1%, p = 0.65), bedridden state or death (40.4% vs 44.7%, p = 0.66), and sICH (3.3% vs 5.7%, p = 0.49) for conventional and advanced imaging groups, respectively. Results were similar across treatment time windows (all p > 0.05). Conclusions: Selecting patients for basilar EVT using conventional versus advanced imaging did not result in different clinical outcomes, regardless of treatment time windows. Conventional imaging appears sufficient as a first-line tool for selecting basilar EVT patients in routine clinical practice.

Background and objectives Arteriovenous malformations (AVMs) with perinidal aneurysms and single draining vein are associated with an elevated risk of rupture and increased procedural complexity. The role of preoperative embolization in this high-risk anatomical subset remains unclear. This study aimed to evaluate the safety and efficacy of microsurgery with preoperative embolization, compared with microsurgery alone in patients with such AVMs. Methods We conducted a multicenter retrospective analysis of an AVM registry from the MISTA (Multicenter International Study for Treatment of Brain AVMs) consortium and included AVMs with perinidal aneurysms and a single draining vein. Baseline characteristics, angiographic outcomes, functional outcomes, and complication rates were compared. Propensity score weighting (PSW) using the covariate balancing method was applied to adjust for baseline differences. Results Out of a total of 1919 patients, 65 met the inclusion criteria; 45 patients underwent preoperative embolization followed by microsurgery, and 20 underwent microsurgery alone. After adjustment, complete obliteration rates were similar between groups (OR 0.87, 95% CI 0.04 to 16.33, P=0.92), as were rates of functional independence at discharge and follow-up. Overall complication, symptomatic complication, and mortality rates did not differ significantly between groups. However, permanent complications were significantly lower in patients with preoperative embolization (OR 0.06, 95% CI 0.004 to 0.84, P=0.03). Discussion In patients with AVMs featuring perinidal aneurysms and single draining vein, preoperative embolization followed by microsurgery was associated with fewer permanent complications and no increase in adverse outcomes compared with microsurgery alone. However, given the small number of events, this finding should be interpreted cautiously.

Background The effectiveness of endovascular thrombectomy (EVT) for low Alberta Stroke Program Early CT score (ASPECTS) stroke patients with occlusion of the second segment of the middle cerebral artery (M2) is unclear. Methods This was a multicenter retrospective study. Patients with M1 or M2 occlusions and low ASPECTS (<6) who underwent successful EVT (modified treatment in cerebral ischemia score of 2b or higher) were included. Primary outcome was futile EVT reperfusion (defined as 90-day modified Rankin scale of 5 or 6). Other outcomes of interest include acceptable outcomes (modified Rankin scale of 3 or less) and intracranial hemorrhage (ICH), and all-cause 90-day mortality. Outcomes for M1 patients were compared to M2 patients with multivariable logistic regression models accounting for potential confounders. Results 173 patients with M1 or M2 occlusions and low ASPECTS (<6) who underwent successful EVT were identified. After multivariable adjustments, M2 patients had significantly higher odds of futile reperfusion (OR 5.48 [95%CI 1.91 to 15.7], p = 0.002), lower odds of acceptable outcomes (OR 0.33 [95%CI 0.12 to 0.89], p = 0.028), and higher odds of all-cause mortality (OR 4.90 [95%CI 1.65 to 14.5], p = 0.004). These findings suggest that EVT's efficacy for low-ASPECTS stroke patients may be diminished for patients with M2 occlusions. M2 occlusion was not significantly associated with ICH. Conclusions Among low-ASEPCTS stroke patients who underwent successful EVT, those with M2 occlusions had significantly higher odds of poor outcome compared to those with M1 occlusions.