Chowdhry, Shakeel

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.

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 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.

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 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.

BACKGROUND AND OBJECTIVES: It remains unclear whether decompressive craniectomy (DC) is beneficial in patients who suffer symptomatic intracerebral hemorrhage (sICH) after acute ischemic stroke (AIS). We sought to study the effect of DC on functional outcomes in patients with sICH after AIS who underwent mechanical thrombectomy (MT). METHODS: Patients with AIS from anterior circulation large vessel occlusion who underwent MT and subsequently developed sICH were identified from the Stroke Thrombectomy and Aneurysm Registry database. The primary outcome was acceptable 90-day functional neurological outcome, defined as modified Rankin scale (mRS) 0-3. Multivariable logistic regression and propensity-score matching were used to identify and quantify risk factors. RESULTS: Of 464 patients identified with sICH after AIS after MT, 97 patients (20.9%) underwent DC. Patients who underwent DC were more likely to be female ( P < .001), younger ( P < .001), have a measured medical comorbidity, have higher baseline mRS ( P = .02), and have higher-grade hemorrhages ( P = .01). At 90 days, 14% of patients had the primary outcome of mRS 0-3 and 56% had died. The primary outcome was observed in 11 patients who underwent DC (11%) and 55 (15%) of those without DC (odds ratio [OR] 0.7, 95% CI 0.4-1.4, P = .40). DC did not affect mRS shift at 90 days ( P = .10) but was associated with lower mortality (OR 0.5, 95% CI 0.3-0.8, P = .01). Multivariable analysis demonstrated that DC decreased the odds of primary outcome (adjusted OR 0.2, 95% CI 0.02-0.9, P = .045), but did not affect mortality ( P = .94), mRS shift ( P = .50), or length of stay ( P = .90). Propensity-matched analysis similarly demonstrated that non-DC patients were more likely to achieve the primary outcome (24% vs 8%, P = .045). CONCLUSION: In patients with sICH after AIS after MT, those selected for DC had less favorable outcomes and similar rates of mortality at 90 days.

Background Larger “macrowires” may facilitate microcatheter-free delivery of large-bore aspiration catheters (ACs) for intracranial endovascular mechanical thrombectomy. We examined the safety and efficacy of the Aristotle Colossus Guidewire for this use. Methods In this retrospective analysis of prospective data from 12 institutions, we identified anterior circulation endovascular mechanical thrombectomy cases involving the Aristotle Colossus guidewire over a 12-month period. The primary efficacy endpoint was successful delivery of the AC to the site without the use of adjunct devices. Multivariable logistic regression was performed with clinically relevant covariables. Results In 122 patients (median age 74 years (interquartile range (IQR) 63–82)), most intracranial occlusions were in the M1 segment of the middle cerebral artery (95/122, 78.0%). The primary endpoint of microcatheter-free AC delivery was met in 87.7% (107/122) of patients; 93/122 (76.2%) patients underwent microcatheter-free delivery with successful reperfusion via contact aspiration (modified thrombolysis in cerebral infarction grade ≥ 2B). The median number of passes was 1 (IQR 1–2). Multivariable regression demonstrated that severe internal carotid artery tortuosity or cervical loop presence (odds ratio (OR): 0.09, 95% confidence interval (CI): 0.01–0.54, p = 0.01) and presence of intracranial atherosclerotic disease (OR: 0.15, 95% CI: 0.03–0.83, p = 0.03) were significantly associated with lower odds of successful AC delivery over the guidewire. Intraprocedural vasospasm occurred in 4.9% (6/122) of cases; there were no reports of vessel dissection or perforation. Conclusions We demonstrate the favorable performance of the Aristotle Colossus guidewire for anterior circulation ischemic stroke intervention. The macrowire appears to safely facilitate navigation of the neurovasculature by large-bore ACs without the need for microcatheter and/or stentriever.

OBJECTIVE The definitive influence of prestroke disability on outcomes in patients with a low Alberta Stroke Program Early CT Score (ASPECTS) treated with endovascular thrombectomy (EVT) for acute ischemic stroke (AIS) due to large-vessel occlusion (LVO) remains unknown. This study aimed to investigate the impact of prestroke disability on outcomes in this specific population. METHODS Data from 32 international centers for AIS-LVO patients with a low ASPECTS who underwent EVT between January 2013 and December 2022 were analyzed retrospectively. Low ASPECTS and prestroke disability were defined as ASPECTS values of 2–5 and prestroke modified Rankin Scale (mRS) score ≥ 2. The primary outcome was a return to the prestroke mRS score at 90 days. Secondary outcomes were independent ambulation (mRS scores of 0–3) or a return to the prestroke mRS score at 90 days, good functional outcome (mRS scores of 0–2) or a return to the prestroke mRS score at 90 days, successful recanalization, and 90-day mortality. Safety outcomes were any intracranial hemorrhage or symptomatic intracranial hemorrhage. A symptomatic intracranial hemorrhage was defined as an intracranial hemorrhage with an associated worsening of ≥ 4 points in the National Institutes of Health Stroke Scale score. Outcomes were compared between patients with and without prestroke disability. RESULTS Of 293 patients, 50 (17.1%) had a prestroke disability. Of 50 patients, 20 (40.0%), 24 (48.0%), and 6 (12.0%) had prestroke mRS scores of 2, 3, and 4, respectively. The primary outcome showed no significant difference between the two groups. Compared with patients without prestroke disability, those with prestroke disability had a significantly smaller proportion of independent ambulation or return to prestroke mRS score (adjusted OR 0.13, 95% CI 0.03–0.53) and good functional outcome or return to prestroke mRS score (adjusted OR 0.21, 95% CI 0.05–0.91). Other secondary and safety outcomes showed no significant difference between the two groups. CONCLUSIONS The present study indicated that prestroke disability was not associated with a return to the prestroke mRS score at 90 days or intracranial hemorrhage. Physicians should not routinely exclude AIS-LVO patients with a low ASPECTS who have prestroke disability from EVT based on prestroke disability alone.

Background The contact aspiration (CA) technique is often used to perform endovascular thrombectomy (EVT) for acute ischemic stroke (AIS); however, rescue strategies are necessary if CA fails to achieve recanalization. This study investigates the outcomes of incorporating stent retriever (SR) thrombectomy in the rescue strategy following failed CA. Methods EVT patients with failed CA attempts were identified from a large multicenter registry and stratified by rescue technique: CA alone or incorporating SR in the rescue strategy. Outcomes included successful recanalization, 90-day functional outcomes (defined by the modified Rankin Scale (mRS) score), symptomatic intracranial hemorrhage (sICH), and 90-day mortality. Results Among 1885 patients with failed CA attempts, conversion to SR was associated with higher recanalization rates (85.2% vs 80.6%; p=0.03), higher rates of second-pass recanalization (31.2% vs 23.4%; p<0.001), and better 90-day outcomes (mRS 0–2: 35.2% vs 29.9%; p=0.04) when compared with repeated CA attempts. Trevo SRs showed higher odds of successful recanalization (adjusted odds ratio (aOR)=1.9; p=0.02), second-pass recanalization (aOR=1.7; p=0.01), and reduced odds of sICH (aOR=0.3; p=0.02). EmboTrap SRs were associated with higher odds of 90-day mortality (aOR=2.6; p=0.004) and sICH (aOR=2.9; p=0.04) and lower odds of recanalization (aOR=0.5; p=0.03). Conclusions Incorporating SR in the rescue strategy after a failed CA improves recanalization rates and functional outcomes. Trevo SRs demonstrated superior efficacy and safety when incorporated into the rescue strategy.