Endovascular management of acute stroke.

Stroke related to large vessel occlusion is a leading cause of disability and death worldwide. Advances in endovascular therapy to reopen occluded arteries have been shown to reduce patient disability and mortality. Expanded indications to treat patients with large vessel occlusion in the late window (>6 h from symptom onset), with basilar artery occlusion, and with large ischaemic core at presentation have enabled treatment of more patients with simplified imaging methods. Ongoing knowledge gaps include an understanding of which patients with large ischaemic infarct are more likely to benefit from endovascular therapy, the role of endovascular therapy in patients who present with low National Institutes of Health Stroke Scale scores or medium or distal vessel occlusion, and optimal management of patients with underlying intracranial atherosclerotic disease. As reperfusion can now be facilitated by intravenous thrombolysis, mechanical thrombectomy, or both, the development of cytoprotective or adjunctive drugs to slow infarct growth, enhance reperfusion, or decrease haemorrhagic risk has gained renewed interest with the hope to improve patient outcomes.

Association of Mismatch Profiles and Clinical Outcome from Endovascular Therapy in Large Infarct: A Post-Hoc Analysis of the ANGEL-ASPECT Trial.

OBJECTIVES: We investigated whether patients with large infarct and the presence or absence of perfusion mismatch are associated with endovascular treatment benefit. METHODS: This is a post-hoc analysis of the Endovascular Therapy in Anterior Circulation Large Vessel Occlusion with a Large Infarct (ANGEL-ASPECT) randomized trial, which enrolled patients within 24 hours of onset with ASPECTS 3 to 5 or ASPECTS 0 to 2 with an infarct core 70 to 100 ml. Mismatch ratio was defined as time-to-maximum (Tmax) >6 s cerebral volume/ischemic core volume, and mismatch volume was defined as Tmax >6 s volume minus ischemic core volume. We divided patients into mismatch ratio ≥1.2 and mismatch volume ≥10 ml, and mismatch ratio ≥1.8 and mismatch volume ≥15 ml groups. The primary outcome was the 90-day modified Rankin Scale score ordinal distribution. Safety outcomes were symptomatic intracranial hemorrhage and 90-day mortality. RESULTS: There were 425 patients included. In both the mismatch ratio ≥1.2 and mismatch volume ≥10 ml (mismatch+, n = 395; mismatch-, n = 31) and mismatch ratio ≥1.8 and mismatch volume ≥15 ml groups (mismatch+, n = 346; mismatch-, n = 80), better 90-day modified Rankin Scale outcomes were found in the endovascular treatment group compared with the MM group (4 [2-5] vs 4 [3-5], common odds ratio [cOR], 1.9, 95% confidence interval [CI] 1.3-2.7, p = 0.001; 4 [2-5] vs 4 [3-5], cOR, 1.9, 95% CI 1.3-2.8, p = 0.001, respectively), but not in patients without mismatch ratio ≥1.2 and mismatch volume ≥10 ml (5 [3-6] vs 5 [4-6], cOR, 1.2, 95% CI 0.3-4.1, p = 0.83), and mismatch ratio ≥1.8 and mismatch volume ≥15 ml (4 [3-6] vs 5 [3-6], cOR, 1.2, 95% CI 0.6-2.7, p = 0.60). However, no interaction effect was found in both subgroups (p interaction >0.10). CONCLUSION: Endovascular treatment was more efficacious than MM in patients with mismatch profiles, but no treatment effect or interaction was noted in the no mismatch profile patients. However, the small sample size of patients with no mismatch may have underpowered our analysis. A pooled analysis of large core trials stratified by mismatch is warranted. ANN NEUROL 2024.

Mechanical Thrombectomy Global Access For Stroke (MT-GLASS): A Mission Thrombectomy (MT-2020 Plus) Study.

BACKGROUND: Despite the well-established potent benefit of mechanical thrombectomy (MT) for large vessel occlusion (LVO) stroke, access to MT has not been studied globally. We conducted a worldwide survey of countries on 6 continents to define MT access (MTA), the disparities in MTA, and its determinants on a global scale. METHODS: Our survey was conducted in 75 countries through the Mission Thrombectomy 2020+ global network between November 22, 2020, and February 28, 2021. The primary end points were the current annual MTA, MT operator availability, and MT center availability. MTA was defined as the estimated proportion of patients with LVO receiving MT in a given region annually. The availability metrics were defined as ([current MT operators×50/current annual number of estimated thrombectomy-eligible LVOs]×100 = MT operator availability) and ([current MT centers×150/current annual number of estimated thrombectomy-eligible LVOs]×100= MT center availability). The metrics used optimal MT volume per operator as 50 and an optimal MT volume per center as 150. Multivariable-adjusted generalized linear models were used to evaluate factors associated with MTA. RESULTS: We received 887 responses from 67 countries. The median global MTA was 2.79% (interquartile range, 0.70-11.74). MTA was <1.0% for 18 (27%) countries and 0 for 7 (10%) countries. There was a 460-fold disparity between the highest and lowest nonzero MTA regions and low-income countries had 88% lower MTA compared with high-income countries. The global MT operator availability was 16.5% of optimal and the MT center availability was 20.8% of optimal. On multivariable regression, country income level (low or lower-middle versus high: odds ratio, 0.08 [95% CI, 0.04-0.12]), MT operator availability (odds ratio, 3.35 [95% CI, 2.07-5.42]), MT center availability (odds ratio, 2.86 [95% CI, 1.84-4.48]), and presence of prehospital acute stroke bypass protocol (odds ratio, 4.00 [95% CI, 1.70-9.42]) were significantly associated with increased odds of MTA. CONCLUSIONS: Access to MT on a global level is extremely low, with enormous disparities between countries by income level. The significant determinants of MT access are the country's per capita gross national income, prehospital LVO triage policy, and MT operator and center availability.

Mechanical Thrombectomy Access Score: A Systematic Review and Modified Delphi of Global Barriers to Endovascular Therapy.

BACKGROUND: The availability of mechanical thrombectomy (MT) for acute ischemic stroke is limited, and vast disparities exist between countries. We aim to create a MT access score to measure the drivers of access to help quantify and accelerate treatment worldwide. METHODS: We used a systematic review complemented by a modified Delphi method. In the first of 3 rounds, 4 independent investigators performed a systematic literature review using key search terms that drive MT access, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. In the second round, a panel of 6 anonymous international experts selected key attributes needed for scoring. In the final round, a total of 12 attributes were selected on consensus, each given a score on a 0 to 3 scale. An ultimate MT access score (range, 0-36) was proposed as a new tool to use in identifying barriers to MT access and assist in providing an initial framework for public health interventions. RESULTS: Of 2864 abstracts screened, 121 studies were included in the final systematic review. A total of 34 attributes that potentially drive MT access were initially identified. In the final round, 12 attributes were selected by the expert panel: public awareness, emergency medical services transportation, prehospital large vessel occlusion screening, interhospital transfer policy, emergency department protocols, stroke imaging protocols, emergency department stroke expertise or telestroke availability, interventionalists, MT-capable centers, device availability, and insurance coverage. These attributes were weighted as part of the final score of 0 to 36. CONCLUSIONS: The MT access score represents the first tool to quantify barriers to global MT access. Its implementation stands not just as an academic achievement but as a beacon of hope for improving stroke care and outcomes worldwide, bringing us a step closer to bridging the gap in stroke treatment disparities.

Value of intravenous thrombolysis in endovascular treatment for large-vessel anterior circulation stroke: individual participant data meta-analysis of six randomised trials.

BACKGROUND: Intravenous thrombolysis is recommended before endovascular treatment, but its value has been questioned in patients who are admitted directly to centres capable of endovascular treatment. Existing randomised controlled trials have indicated non-inferiority of endovascular treatment alone or have been statistically inconclusive. We formed the Improving Reperfusion Strategies in Acute Ischaemic Stroke collaboration to assess non-inferiority of endovascular treatment alone versus intravenous thrombolysis plus endovascular treatment. METHODS: We conducted a systematic review and individual participant data meta-analysis to establish non-inferiority of endovascular treatment alone versus intravenous thrombolysis plus endovascular treatment. We searched PubMed and MEDLINE with the terms "stroke", "endovascular treatment", "intravenous thrombolysis", and synonyms for articles published from database inception to March 9, 2023. We included randomised controlled trials on the topic of interest, without language restrictions. Authors of the identified trials agreed to take part, and individual participant data were provided by the principal investigators of the respective trials and collated centrally by the collaborators. Our primary outcome was the 90-day modified Rankin Scale (mRS) score. Non-inferiority of endovascular treatment alone was assessed using a lower boundary of 0·82 for the 95% CI around the adjusted common odds ratio (acOR) for shift towards improved outcome (analogous to 5% absolute difference in functional independence) with ordinal regression. We used mixed-effects models for all analyses. This study is registered with PROSPERO, CRD42023411986. FINDINGS: We identified 1081 studies, and six studies (n=2313; 1153 participants randomly assigned to receive endovascular treatment alone and 1160 randomly assigned to receive intravenous thrombolysis and endovascular treatment) were eligible for analysis. The risk of bias of the included studies was low to moderate. Variability between studies was small, and mainly related to the choice and dose of the thrombolytic drug and country of execution. The median mRS score at 90 days was 3 (IQR 1-5) for participants who received endovascular treatment alone and 2 (1-4) for participants who received intravenous thrombolysis plus endovascular treatment (acOR 0·89, 95% CI 0·76-1·04). Any intracranial haemorrhage (0·82, 0·68-0·99) occurred less frequently with endovascular treatment alone than with intravenous thrombolysis plus endovascular treatment. Symptomatic intracranial haemorrhage and mortality rates did not differ significantly. INTERPRETATION: We did not establish non-inferiority of endovascular treatment alone compared with intravenous thrombolysis plus endovascular treatment in patients presenting directly at endovascular treatment centres. Further research could focus on cost-effectiveness analysis and on individualised decisions when patient characteristics, medication shortages, or delays are expected to offset a potential benefit of administering intravenous thrombolysis before endovascular treatment. FUNDING: Stryker and Amsterdam University Medical Centers, University of Amsterdam.

Systemic Immune-Inflammation Response is Associated with Futile Recanalization After Endovascular Treatment.

BACKGROUND: Frequent incidence of futile recanalization decreases the benefit of endovascular treatment (EVT) in acute ischemic stroke. We hypothesized that the inflammation and immune response after ischemic are associated with futile recanalization. We aimed to investigate the correlation of admission systemic immune-inflammation index (SII) with futile recanalization post EVT. METHODS: Patients with successful recanalization (modified Thrombolysis in Cerebral Ischemia angiographic score 2b-3) and maintained artery recanalized after 24 h of EVT were chosen from a prospective nationwide registry study. Futile recanalization was defined as a poor functional outcome (modified Rankin Scale score 3-6) at 90 days, irrespective of a successful recanalization. At admission, SII was calculated as (platelet count × neutrophil count)/lymphocyte count/100. Logistic regression analysis helped to test the relationship of SII with futile recanalization. RESULTS: Among the 1,002 patients included, futile recanalization occurred in 508 (50.70%). No matter whether tested as quartiles or continuous variables, SII was significantly associated with futile recanalization (P < 0.05), and for every one standard deviation increase of SII, the risk of futile recanalization elevated by 22.3% (odds ratio 1.223, 95% confidence interval 1.053-1.444, P = 0.0093). Moreover, no significant interactions could be observed between SII or SII quartiles and age, baseline National Institutes of Health Stroke Scale scores, onset-to-recanalization time, and modified Thrombolysis in Cerebral Ischemia angiographic scores (all P for interaction > 0.05). CONCLUSIONS: Early SII elevation was associated with an increased risk of futile recanalization among patients with EVT. Our results indicated that therapeutic drug targeting hyperreactive immune-inflammation response might be helpful for reducing the incidence of futile recanalization.

Balloon Angioplasty vs Medical Management for Intracranial Artery Stenosis: The BASIS Randomized Clinical Trial.

Importance: Previous randomized clinical trials did not demonstrate the superiority of endovascular stenting over aggressive medical management for patients with symptomatic intracranial atherosclerotic stenosis (sICAS). However, balloon angioplasty has not been investigated in a randomized clinical trial. Objective: To determine whether balloon angioplasty plus aggressive medical management is superior to aggressive medical management alone for patients with sICAS. Design, Setting, and Participants: A randomized, open-label, blinded end point clinical trial at 31 centers across China. Eligible patients aged 35 to 80 years with sICAS defined as recent transient ischemic attack (<90 days) or ischemic stroke (14-90 days) before enrollment attributed to a 70% to 99% atherosclerotic stenosis of a major intracranial artery receiving treatment with at least 1 antithrombotic drug and/or standard risk factor management were recruited between November 8, 2018, and April 2, 2022 (final follow-up: April 3, 2023). Interventions: Submaximal balloon angioplasty plus aggressive medical management (n = 249) or aggressive medical management alone (n = 252). Aggressive medical management included dual antiplatelet therapy for the first 90 days and risk factor control. Main Outcomes and Measures: The primary outcome was a composite of any stroke or death within 30 days after enrollment or after balloon angioplasty of the qualifying lesion or any ischemic stroke in the qualifying artery territory or revascularization of the qualifying artery after 30 days through 12 months after enrollment. Results: Among 512 randomized patients, 501 were confirmed eligible (mean age, 58.0 years; 158 [31.5%] women) and completed the trial. The incidence of the primary outcome was lower in the balloon angioplasty group than the medical management group (4.4% vs 13.5%; hazard ratio, 0.32 [95% CI, 0.16-0.63]; P < .001). The respective rates of any stroke or all-cause death within 30 days were 3.2% and 1.6%. Beyond 30 days through 1 year after enrollment, the rates of any ischemic stroke in the qualifying artery territory were 0.4% and 7.5%, respectively, and revascularization of the qualifying artery occurred in 1.2% and 8.3%, respectively. The rate of symptomatic intracranial hemorrhage in the balloon angioplasty and medical management groups was 1.2% and 0.4%, respectively. In the balloon angioplasty group, procedural complications occurred in 17.4% of patients and arterial dissection occurred in 14.5% of patients. Conclusions and Relevance: In patients with sICAS, balloon angioplasty plus aggressive medical management, compared with aggressive medical management alone, statistically significantly lowered the risk of a composite outcome of any stroke or death within 30 days or an ischemic stroke or revascularization of the qualifying artery after 30 days through 12 months. The findings suggest that balloon angioplasty plus aggressive medical management may be an effective treatment for sICAS, although the risk of stroke or death within 30 days of balloon angioplasty should be considered in clinical practice. Trial Registration: ClinicalTrials.gov Identifier: NCT03703635.

Time to Treatment With Intravenous Thrombolysis Before Thrombectomy and Functional Outcomes in Acute Ischemic Stroke: A Meta-Analysis.

Importance: The benefit of intravenous thrombolysis (IVT) for acute ischemic stroke declines with longer time from symptom onset, but it is not known whether a similar time dependency exists for IVT followed by thrombectomy. Objective: To determine whether the benefit associated with IVT plus thrombectomy vs thrombectomy alone decreases with treatment time from symptom onset. Design, Setting, and Participants: Individual participant data meta-analysis from 6 randomized clinical trials comparing IVT plus thrombectomy vs thrombectomy alone. Enrollment was between January 2017 and July 2021 at 190 sites in 15 countries. All participants were eligible for IVT and thrombectomy and presented directly at thrombectomy-capable stroke centers (n = 2334). For this meta-analysis, only patients with an anterior circulation large-vessel occlusion were included (n = 2313). Exposure: Interval from stroke symptom onset to expected administration of IVT and treatment with IVT plus thrombectomy vs thrombectomy alone. Main Outcomes and Measures: The primary outcome analysis tested whether the association between the allocated treatment (IVT plus thrombectomy vs thrombectomy alone) and disability at 90 days (7-level modified Rankin Scale [mRS] score range, 0 [no symptoms] to 6 [death]; minimal clinically important difference for the rates of mRS scores of 0-2: 1.3%) varied with times from symptom onset to expected administration of IVT. Results: In 2313 participants (1160 in IVT plus thrombectomy group vs 1153 in thrombectomy alone group; median age, 71 [IQR, 62 to 78] years; 44.3% were female), the median time from symptom onset to expected administration of IVT was 2 hours 28 minutes (IQR, 1 hour 46 minutes to 3 hours 17 minutes). There was a statistically significant interaction between the time from symptom onset to expected administration of IVT and the association of allocated treatment with functional outcomes (ratio of adjusted common odds ratio [OR] per 1-hour delay, 0.84 [95% CI, 0.72 to 0.97], P = .02 for interaction). The benefit of IVT plus thrombectomy decreased with longer times from symptom onset to expected administration of IVT (adjusted common OR for a 1-step mRS score shift toward improvement, 1.49 [95% CI, 1.13 to 1.96] at 1 hour, 1.25 [95% CI, 1.04 to 1.49] at 2 hours, and 1.04 [95% CI, 0.88 to 1.23] at 3 hours). For a mRS score of 0, 1, or 2, the predicted absolute risk difference was 9% (95% CI, 3% to 16%) at 1 hour, 5% (95% CI, 1% to 9%) at 2 hours, and 1% (95% CI, -3% to 5%) at 3 hours. After 2 hours 20 minutes, the benefit associated with IVT plus thrombectomy was not statistically significant and the point estimate crossed the null association at 3 hours 14 minutes. Conclusions and Relevance: In patients presenting at thrombectomy-capable stroke centers, the benefit associated with IVT plus thrombectomy vs thrombectomy alone was time dependent and statistically significant only if the time from symptom onset to expected administration of IVT was short.

Outcomes of antiplatelet therapy before endovascular treatment of acute large vessel occlusion: Data from the ANGEL-ACT registry.

OBJECTIVES: To investigate whether single or dual antiplatelet therapy (SAPT or DAPT) within 24 hours before endovascular treatment (EVT) could improve the clinical outcomes of patients with large vessel occlusion (LVO). METHODS: Patients from the ANGEL-ACT registry were divided into antiplatelet therapy (APT) and non-APT groups. The APT group was divided into SAPT and DAPT groups. Outcome measurement included 90-day modified Rankin Scale (mRS) distribution, change in the NIHSS at 7 days or discharge, number of passes, modified first pass effect (mFPE), symptomatic intracranial hemorrhage (SICH), and mortality within 90 days. To compare the outcomes, we performed multivariable analyses by adjusting for the propensity score calculated by the logistic regression model. RESULTS: Of 1611 patients, 1349 were in the non-APT group, while 262 (16.3 %) were in the APT group (122 [46.6 %] received SAPT, 140 [53.4 %] received DAPT). APT, SAPT or DAPT were not associated with a shift to better outcomes (non-APT vs. APT, 3[0-5] vs. 3[0-5], common odds ratio [OR], 1.04, 95 %confidence interval [CI]:0.82-1.34, P = 0.734). DAPT was associated with mFPE (OR,2.05, 95 %CI:1.39-3.01, P<0.001), more NIHSS reduction at 7 days or discharge (ß, -2.13, 95 %CI: -4.02--0.24, P = 0.028), lower number of passes (ß, -0.40, 95 %CI: -0.68--0.12, P=0.006), and shorter procedure duration (ß, -12.4, 95 %CI: -23.74--1.05, P = 0.032) without increasing odds of successful recanalization, PH within 24 hours and mortality with 90 days . CONCLUSIONS: APT before MT for AIS due to LVO does not affect clinical outcome in 90 days despite a tendency to reduce MT procedure time and number of passes. APT before MT in LVO does not increase SICH or mortality rates.

Association of baseline blood pressure and outcomes in etiology subtypes of large vessel occlusion stroke: Data from ANGEL-ACT registry.

BACKGROUND: Blood pressure (BP) management at the initial stage of stroke caused by large-vessel occlusion (LVO) remains challenging. We assessed the association between baseline BP and clinical and safety outcomes of endovascular treatment (EVT) in different stroke etiologies. METHODS: Patients with acute ischemic stroke and anterior circulation LVO were screened from a prospective, multicenter registry of EVT from November 2017 to March 2019. The primary outcome was poor 90-day outcome (modified Rankin Scale score 3-6). The safety outcome was 24 h post-procedure parenchymal hematoma (PH). The Trial of Org 101072 in Acute Stroke Treatment criteria were used for etiologic stroke classification. Restricted cubic spline and binary logistic regression analysis were performed to examine the association between study outcomes and natural log-transformed BP. RESULTS: In subgroup analyses, a U-shaped correlation existed between baseline mean arterial pressure (MAP) and poor outcome in large-artery atherosclerosis stroke only. Higher MAP was an independent risk factor compared with a central reference value (≥ 133 mm Hg vs 96-115 mm Hg; adjusted OR [aOR], 2.50; 95 % CI, 1.09 to 5.71, P = 0.030). Whereas elevated MAP was associated with PH (aOR, 1.58; 95 % CI 1.04 to 2.39, P = 0.030 for a ln10-unit increase in natural log-transformed MAP) in the range <110 mm Hg exclusively for cardioembolic stroke. CONCLUSION: Whether it is cause or epiphenomenon, baseline BP was associated with 90-day outcome in large-artery atherosclerosis stroke, whereas in cardioembolic stroke baseline BP was correlated with post-procedure PH within a certain range. Identifying these features based on etiological subtypes may offer a reference for BP management in acute LVO stroke.

Clinically Ineffective Reperfusion After Endovascular Therapy in Acute Ischemic Stroke.

Endovascular treatment is a highly effective therapy for acute ischemic stroke due to large vessel occlusion. However, in clinical practice, nearly half of the patients do not have favorable outcomes despite successful recanalization of the occluded artery. This unfavorable outcome can be defined as having clinically ineffective reperfusion. The objective of the review is to describe clinically ineffective reperfusion after endovascular therapy and its underlying risk factors and mechanisms, including initial tissue damage, cerebral edema, the no-reflow phenomenon, reperfusion injury, procedural features, and variations in postprocedural management. Further research is needed to more accurately identify patients at a high risk of clinically ineffective reperfusion after endovascular therapy and to improve individualized periprocedural management strategies, to increase the chance of achieving favorable clinical outcomes.

Sex-Related Differences in Outcomes of Endovascular Treatment for Anterior Circulation Large Vessel Occlusion.

BACKGROUND: Sex disparities in acute large vessel occlusion (LVO) following endovascular treatment (EVT) have been recently reported. However, there is uncertainty about the effect of sex differences on functional outcomes after EVT, particularly in an Asian population. The present study aimed to compare the clinical and safety outcomes between men and women with anterior circulation LVO treated with EVT. METHODS: We analyzed data from the ANGEL-ACT (Endovascular Treatment Key Technique and Emergency Work Flow Improvement of Acute Ischemic Stroke: a Prospective Multicenter Registry Study) Registry, which was conducted at 111 hospitals from 26 provinces in China between November 2017 and March 2019. Men and women with anterior circulation LVO treated with EVT were matched using propensity scores. After a 1:1 propensity score matching, we compared the clinical outcomes including 90-day ordinal modified Rankin Scale distribution (primary outcome), procedure duration, successful reperfusion, symptomatic intracranial hemorrhage, and mortality. Furthermore, we explored sex modification on the primary outcome in subgroup analysis. RESULTS: Of 1321 patients, 483 (36.6%) were women and 838 (63.4%) were men. The mean age for women and men were 68 and 62 years old, respectively. Among 578 patients identified after matching, there were no sex differences (men versus women) in 90-day ordinal modified Rankin Scale distribution (median [interquartile range], 4 [1-5] versus 3 [1-5], P=0.464), successful reperfusion (86.5% versus 91.0%, P=0.089), symptomatic intracranial hemorrhage (6.5% versus 7.9%, P=0.512), and mortality within 90 days (17.7% versus 17.0%, P=0.826). However, men had a longer median procedure duration than women (86 [52-128] versus 72 [48-110] minutes, ß=14.51, [95% CI, 4.19-24.84]; P=0.006). Subgroup analysis showed that in patients with National Institutes of Health Stroke Scale score <15, women tended to have a better outcome than men, whereas there was no gender effect in those with National Institutes of Health Stroke Scale score ≥15 (P for interaction=0.032). CONCLUSIONS: Overall, this matched-control study from the ANGEL-ACT study showed similar clinical outcomes between men and women with anterior circulation LVO treated with EVT. However, in the subgroup of patients presenting with lower stroke severity (ie, National Institutes of Health Stroke Scale score <15), women tended to have a better outcome than men highlighting a potential sex disparity for further investigation. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT03370939.

New Diffusion Abnormalities Following Endovascular Treatment for Intracranial Atherosclerosis.

Background There are limited data on new ischemic brain lesions after endovascular treatment for symptomatic intracranial atherosclerotic stenosis (ICAS). Purpose To investigate the (a) characteristics of new ischemic brain lesions at diffusion-weighted MRI (new diffusion abnormalities) after endovascular treatment, (b) characteristics between those treated with balloon angioplasty and stent placement procedures, and (c) predictors of new ischemic brain lesions. Materials and Methods Patients with symptomatic ICAS in whom maximum medical therapy failed were prospectively enrolled between April 2020 and July 2021 from a national stroke center and underwent endovascular treatment. All study participants underwent thin-section diffusion-weighted MRI (voxel size, 1.4 × 1.4 × 2 mm3 with no section gap) before and after treatment. The characteristics of new ischemic brain lesions were recorded. Multivariable logistic regression analysis was performed to determine potential predictors of new ischemic brain lesions. Results A total of 119 study participants (mean age, 59 years ± 11 [SD]; 81 men; 70 treated with balloon angioplasty and 49 with stent placement) were enrolled. Of the 119 participants, 77 (65%) had new ischemic brain lesions. Five of the 119 participants (4%) had symptomatic ischemic stroke. New ischemic brain lesions were located in (61%, 72 of 119) and/or beyond (35%, 41 of 119) the territory of the treated artery. Of the 77 participants with new ischemic brain lesions, 58 (75%) had lesions located in peripheral brain areas. There was no evidence of a difference in the frequency of new ischemic brain lesions between the balloon angioplasty and stent groups (60% vs 71%, P = .20). In adjusted models, cigarette smoking (odds ratio [OR], 3.6; 95% CI: 1.3, 9.7) and more than one operative attempt (OR, 2.9; 95% CI: 1.2, 7.0) were independent predictors of new ischemic brain lesions. Conclusion New ischemic brain lesions on diffusion-weighted MRI scans were common after endovascular treatment for symptomatic intracranial atherosclerotic stenosis, and occurrence may be associated with cigarette smoking and the number of operative attempts. Clinical trial registration no. ChiCTR2100052925 © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Russell in this issue.

Estimation of venous sinus pressure drop in patients with idiopathic intracranial hypertension using 4D-flow MRI.

OBJECTIVE: We aimed to explore a non-invasive estimate of pressure drop in patients who undergo venous sinus stenting to treat idiopathic intracranial hypertension (IIH). METHODS: This prospective study included 28 IIH patients scheduled for venous stenting. 4D-flow MRI was acquired 24-48 h before venous manometry. Manometry-obtained pressure drop (Mp) was dichotomized into low (Lp: 0-8 mmHg) and high (Hp: 8-30 mmHg) groups. Hemodynamic indices were compared between Lp and Hp. Trans-stenotic pressure drop was estimated by work-energy equation, simplified Bernoulli equation, vorticity magnitude, and velocity difference between inlet and outlet and was compared with Mp. Measurement agreement, correlation, and accuracy were evaluated using the κ coefficient, Pearson's r, and confusion matrix-derived accuracy. RESULTS: Among 28 patients (mean age 38.8 ± 12.7), 19 (67.9%) were female. Work-energy equation-estimated pressure drop (WEp) had strong correlation (r = 0.91, 95% confidence interval [CI]: 0.81-0.96, p < 0.001) and high agreement (intraclass correlation coefficient = 0.90, 95% CI: 0.78-0.95, p < 0.001) with Mp. WEp classified Lp and Hp with an accuracy of 0.96. The κ value between WEp and Mp was 0.92 (95% CI: 0.78-1.00). In the work-energy equation, the viscosity energy term (Ve) had the largest weights, and the ratio of Ve to the summation of the three energy terms was 0.93 ± 0.07. Ve had strong correlation with mVort (r = 0.93, 95% CI: 0.85-0.97, p < 0.001), and mean vorticity magnitude was significantly elevated in Hp compared to that in Lp (259.8 vs. 174.9 mL/s, p < 0.001). CONCLUSION: Trans-stenotic pressure drop in IIH can be estimated using the work-energy equation with favorable accuracy. KEY POINTS: • Trans-stenotic pressure drop in patients with idiopathic intracranial hypertension can be estimated accurately with the work-energy equation using the 4D-flow MRI full velocity field. • Compared with traditional venous sinus manometry, the 4D-flow MRI-derived pressure drop is totally non-invasive and cost-saving. • 4D-flow MRI may help neurointerventionalist to select IIH patients suitable for venous sinus stenting.

The Effects of Pressure Gradient on Papilledema Improvement After Venous Sinus Stenting in Idiopathic Intracranial Hypertension.

PURPOSE: This study aimed to evaluate the impact of the pressure gradient on papilledema after stenting in patients with idiopathic intracranial hypertension (IIH) patients and venous sinus stenosis (VSS). MATERIALS AND METHODS: In this prospective cohort study, we examined 121 patients with IIH and VSS who underwent stenting. The papilledema Frisen grade at the 1-month follow-up was used as a grouping factor (favorable outcome: 0-1; unfavorable outcome: 2-5). We used multivariable logistic regression modeling to determine independent predictors of favorable outcome. The performance of the prediction model was evaluated using a receiver operating characteristic (ROC) analysis. RESULTS: A total of 96 patients had papilledema grades 0 to 1, and 25 patients had papilledema grades 2 to 5. Patients with the first group had significantly lower gradient pressures preoperatively (15.2 mmHg vs. 21.4 mmHg, p=0.001) and postoperatively (2 mmHg vs. 3.3 mmHg, p=0.002) relative to those in the second group. Multivariate analysis indicated that preoperative pressure gradient (odds ratio [OR] = 1.119; 95% confidence interval [CI] = 1.034-1.211]) and postoperative pressure gradient (OR = 1.498; 95% CI = 1.147-1.957) were independent predictors of favorable outcome. In the ROC analysis, the cut-off pressure gradient for the highest sensitivity (0.44) and specificity (0.874) was 22.75 mmHg, with a Youden's index of 0.314. Survival analysis demonstrated that patients with a preoperative pressure gradient <22.75 mmHg had more rapid improvement of papilledema than did those with a pressure gradient >22.75 mmHg (mean+SD: 2.639+0.382 [95% CI: 1.890-3.388] versus mean+SD: 3.882+0.884 [95% CI: 2.149-5.616]; p=0.004). CONCLUSION: A significant reduction in the pressure gradient appears to be strongly correlated with the success of VSS in patients with IIH. A higher preoperative pressure gradient may reduce stenting efficacy in patients with IIH. CLINICAL IMPACT: Venous sinus stenting has the potential to yield substantial clinical advantages in individuals diagnosed with idiopathic intracranial hypertension with venous sinus stenosis. Nevertheless, a heightened preoperative pressure gradient could lead to less favorable results. Thus, the early adoption of venous sinus stenting is advised to avert additional irreversible clinical deterioration among idiopathic intracranial hypertension patients with venous sinus stenosis.

History of Neurointervention.

In this review article, we aim to provide a summary of the discoveries and developments that were instrumental in the evolution of the Neurointerventional field. We begin with developments in the advent of Diagnostic Cerebral Angiography and progress to cerebral aneurysm treatment, embolization in AVMs and ischemic stroke treatment. In the process we discuss many persons who were key in the development and maturation of the field. A pivotal aspect to rapid growth in the field has been the multidisciplinary involvement of the different neuroscience specialties and therefore we close out our discussion with excitement about ongoing and future developments in the field with a focus on treatments in the non-cerebrovascular disease realm.

Endovascular Thrombectomy for Anterior Circulation Large Vessel Occlusion Stroke: An Evolution of Trials.

The last decade's progress in demonstrating the clinical benefit of endovascular thrombectomy (EVT) in patients with large vessel occlusion stroke has transformed the paradigm of care for these patients. This review presents the milestones in implementing EVT as standard of care, demonstrates the current state of evidence, provides guidance for identifying the candidate patient for EVT, and highlights unsolved and controversial issues. Ongoing trials investigate broadening of EVT indications for patients who present with large core infarction, adjunctive intra-arterial thrombolysis, medium vessel occlusion, low NIHSS, and tandem occlusion.

Endovascular Treatment for Acute Large Vessel Occlusion Due to Underlying Intracranial Atherosclerotic Disease.

Intracranial atherosclerotic disease (ICAD) is one of the most common causes of acute ischemic stroke worldwide. Patients with acute large vessel occlusion due to underlying ICAD (ICAD-LVO) often do not achieve successful recanalization when undergoing mechanical thrombectomy (MT) alone, requiring rescue treatment, including intra-arterial thrombolysis, balloon angioplasty, and stenting. Therefore, early detection of ICAD-LVO before the procedure is important to enable physicians to select the optimal treatment strategy for ICAD-LVO to improve clinical outcomes. Early diagnosis of ICAD-LVO is challenging in the absence of consensus diagnostic criteria on noninvasive imaging and early digital subtraction angiography. In this review, we summarize the clinical and diagnostic criteria, prediction of ICAD-LVO prior to the procedure, and EVT strategy of ICAD-LVO and provide recommendations according to the current literature.

Prognostic value of pretreatment diffusion-weighted imaging score for acute basilar artery occlusion with successful endovascular recanalization.

PURPOSE: The aim of this study is to test the prognostic value of a diffusion-weighted imaging (DWI) score in acute basilar artery occlusion (ABAO) with successful recanalization. METHODS: The DWI-based pons-midbrain and thalamus (PMT) score was developed to assess posterior circulation infarcts. We test its prognostic value and compare it with other two established scales, the DWI-based posterior circulation acute stroke prognosis Early CT score (PC-ASPECTS) and brain stem score (BSS). A retrospective cohort of consecutive ABAO patients with pretreatment magnetic resonance imaging and successful recanalization (defined as modified Thrombolysis in Cerebral Infarction 2b-3) were analyzed. A favorable outcome was defined as a 90-day modified Rankin Scale (mRS) score of 2 or less. The prognostic performance of three scales was estimated by receiver operating characteristic (ROC) curve analyses. RESULTS: One hundred and sixteen eligible patients (mean age, 59.1 ± 11.7 [standard deviation]; 96 [82.8%] man) were included and evaluated. Between favorable (mRS ≤ 2) and unfavorable groups, the baseline PMT score (median [interquartile range], 3 [1-4] versus 6 [5-8]; P < 0.001) differs significantly. ROC curve analyses showed the PMT score had the best prognostic value for favorable outcome (area under the curve, PMT versus BSS versus PC-ASPECTS = 0.80 versus 0.72 versus 0.68, P = 0.010). Multivariate logistic regression analyses showed baseline National Institute of Health stroke scale (OR, 0.90 [95%CI, 0.86-0.95], P = 0.004) and PMT score < 5 (OR, 17.83 [95%CI, 3.91-81.19], P < 0.001) were independent prognostic factors of favorable outcome. CONCLUSIONS: The PMT score seems to predict clinical outcome of ABAO patients with successful recanalization.

Predictors of poor outcome after endovascular treatment for acute vertebrobasilar occlusion: data from ANGEL-ACT registry.

PURPOSE: Acute vertebrobasilar artery occlusion (VBAO) is a catastrophic disease for patients. There is evidence that the eventual patient outcome depends on patient-specific and procedural factors. This study aimed to identify the incidence and independent predictors of the 90-day poor outcome in VBAO after endovascular treatment (EVT). METHODS: Subjects were selected from the ANGEL-ACT registry. The 90-day poor outcome was defined as a 90-day modified Rankin Scale (mRS) of 4 to 6. Logistic regression analyses were performed to determine the independent predictors of the 90-day poor outcome. RESULTS: Of the 347 enrolled patients with acute VBAO undergoing EVT, 176 (50.7%) experienced the 90-day poor outcome. Multivariate logistic regression indicated that only the use of general anesthesia (GA) (odds ratio [OR] = 2.04; 95% confidence interval [CI], 1.23-3.37; P = 0.006) and heparin during the procedure (OR =1.74; 95% CI, 1.06-2.86; P = 0.028), admission National Institute of Health Stroke Scale (NIHSS) ≥ 26 (OR=3.96; 95% CI, 2.37-6.61; P < 0.001), and time from onset to puncture (OTP) ≥ 395 min (OR=1.91; 95% CI, 1.14-3.20; P = 0.014) and procedure duration ≥ 102 min (OR = 1.70; 95% CI, 1.04-2.79; P = 0.036) were independent predictors of the 90-day poor outcome after EVT. Furthermore, admission NIHSS (OR > 36 vs. ≤ 11 = 9.01, P for trend < 0.001), OTP (OR > 441min vs. ≤ 210 min = 2.71, P for trend = 0.023), and procedure duration (OR > 145 min vs. ≤ 59 min = 2.77, P for trend = 0.031) were significantly associated with increasing risk of the 90-day poor outcome. CONCLUSIONS: Poor outcome after EVT at 90 days occurred in 50.7% of acute VBAO patients from the ANGEL-ACT registry. Our study found several predictors of the 90-day poor outcome which should be highly considered in daily practice to improve acute VBAO management. CLINICAL TRIAL REGISTRATION : http://www. CLINICALTRIALS: gov . Unique identifier: NCT03370939.