Endovascular Thrombectomy

Acute ischemic stroke (AIS), particularly if it is caused by a large-vessel occlusion (LVO), is a severe and life-threatening disease. Endovascular therapy (EVT) has rendered safe and effective treatment of AIS due to LVO possible, and new thrombolytic agents and neuroprotectants could soon complement pharmacological AIS therapy. These treatments are highly time dependent. Hence, the overarching goal in the management of patients with AIS is to rapidly and safely transfer, diagnose, and treat patients with AIS (1). The only available 2 treatment options are intravenous alteplase and endovascular therapy (mechanical clot removal), both of which are highly time dependent. Thus, rapid patient transfer, diagnosis, and treatment are crucial, and time-consuming imaging methods and overly selective treatment selection criteria should be avoided (2). Imaging is crucial for AIS management, as it confirms the diagnosis and guides treatment, with intravenous tissue plasminogen activator (alteplase) and/or EVT, the 2 evidence-based treatment strategies for AIS. Every 30-min delay in recanalization decreases the chance of a good functional outcome by 8% to 14% (3). Clinical outcome after large-vessel occlusive strokes depends on admitting clinical condition, successful recanalization, and robust collateral circulation. However, predicting successful recanalization and quantifying collateral status in the acute setting remain elusive (4). Successful recanalization has many predictive factors. Strong evidence supports increasing clot length being associated with poor recanalization. Current imaging techniques completed in the acute setting suggest that clot length can be estimated with a clot burden score (5). Studies consistently show that independent predictors in clinical outcome remain the patient's admission clinical condition as evaluated by baseline NIH Stroke Scale (NIHSS) scores and ischemic lesion volume. Emphasis on lesion volume suggested that stroke mechanism, particularly lacunar strokes with their smaller ischemic volumes, could be an independent predictor for favorable clinical outcome. However, predicting clinical outcome with stroke mechanism, particularly in large vessel occlusions (LVO), remains elusive (6). As thrombus origin site (i.e., vein, artery, or heart) is thought to play a role in clot composition, cardioembolic and paradoxical strokes with their greater fibrin content and red cells were thought to be more susceptible to fibrinolysis than heterogeneous, chronic thrombotic arterial plaques formed in artery-to-artery strokes. However, studies continue to show that stroke mechanism does not influence recanalization or clinical outcome after intravenous rt-PA (IVtPA) (7). Radiological signs that are readily available on a patient's index CT scan have generated interest as predictors for patients undergoing EVT for LVO AIS. For example, poor baseline collateral flow status and Alberta Stroke Program Early CT Score (ASPECTS), assessed via CT angiography, are associated with a larger ischemic core and worse functional outcomes. Other radiological variables which have been investigated include clot characteristics including clot length, density, surface phenotype, truncal versus branch-type occlusions and the presence of a meniscus sign. Further radiological variables that have been studied pertain to vascular anatomy and include parameters that quantify vascular tortuosity such as the aortic arch type (8). Despite advances in the management of acute ischemic stroke due to large-vessel occlusion, significant variability still exists in both clinical and radiological outcomes among patients. Moreover, the relative contribution and interaction of different clinical and imaging predictors in determining treatment success and functional recovery remain not fully established. In addition, there is still no complete consensus regarding the most reliable predictors of recanalization and favorable outcomes in the acute setting, particularly in relation to thrombus characteristics, collateral status, and vascular anatomy (9). Therefore, this study aims to evaluate factors affecting clinical and radiological outcome in management of acute ischemic stroke due to large vessel occlusion.

Study Design and Duration: This domain will be conducted as part of ACT-GLOBAL platform trial and will have the nested domain name of REACT. It has a prospective, randomised, controlled, open-label, parallel group with blinded endpoint assessment (PROBE) design of up to 1,500 subjects with Acute Ischemic Stroke (AIS) who undergo EVT. Randomisation will be stratified by country/ region, and the IA thrombolytic agent (tenecteplase or alteplase). Minimal sufficient balance algorithm will operate within each stratum to preserve balance on key covariates while maintaining allocation randomness. Participants will be followed for 90 days (or until death, if prior to 90 days). The end of the trial is defined as the date that all participants have completed their Day 90 assessment. Primary outcome data will be determined by simplified, structured method of assessment using the modified Rankin scale (mRS), conducted through centralized telephone interviews or online media performed by central trial personnel blinded to treatment assignment and received. Domain Interventions: The intervention group will receive a single dose of local intraarterial thrombolysis using either tenecteplase (at a dose of 0.0625mg/kg; maximum dose of 6.25mg) or alteplase (0.225 mg/kg; maximum dose, 20mg) at the end of EVT procedure plus standard of care while the control group will receive standard of care alone. The selection of the thrombolytic agent will be determined according to local availability. The dose of intraarterial thrombolysis will be increased if the above dose meets prespecified posterior probabilities at the first or second interims. In all eligible patients: 1. Local intra-arterial thrombolysis using either tenecteplase at a dose of 0.0625mg/kg "maximum dose of 6.25mg" or alteplase "0.225 mg/kg; maximum dose, 20mg\* 2. No intra-arterial thrombolysis. * The dose of IA thrombolysis may be doubled to 0.125 mg/kg tenecteplase or 0.45 mg/kg alteplase if this dose shows futility at pre-specified interims Randomization will be stratified by country/ region, the IA thrombolytic agent used (tenecteplase or alteplase). IA thrombolysis will be administered as a one-time treatment.

Endovascular thrombectomy (EVT) improves outcomes in patients with acute large vessel occlusion (LVO). However, despite successful recanalization rates exceeding 80%, fewer than 50% of patients achieve favorable functional outcomes at 90 days, indicating a high rate of futile recanalization. Potential mechanisms include no-reflow, reperfusion injury, and microcirculatory dysfunction, which are closely associated with post-recanalization neuroinflammation. Minocycline is a second-generation tetracycline with pleiotropic neuroprotective effects, including inhibition of microglial activation, reduction of inflammatory mediators, suppression of matrix metalloproteinases, attenuation of oxidative stress, and preservation of blood-brain barrier integrity. Prior preclinical and clinical studies suggest that minocycline may improve neurological outcomes in acute ischemic stroke. This study is a multicenter, prospective, double-blind, randomized controlled trial designed to evaluate the safety and efficacy of adjunctive minocycline in patients with acute anterior circulation LVO who achieve successful recanalization after EVT. The trial will assess whether early administration of minocycline improves functional outcomes and reduces futile recanalization.

Acute ischemic stroke (AIS) is a leading cause of mortality and long-term disability worldwide. Among these, stroke caused by large vessel occlusion (LVO) are associated with particularly poor outcomes. Multiple randomized controlled trials have demonstrated that endovascular thrombectomy (EVT) significantly improves clinical outcomes in patients with acute LVO and is recommended as the standard of care by current guidelines. Posterior circulation strokes account for approximately 20% of all ischemic strokes and are generally associated with worse prognosis than anterior circulation strokes, especially in patients with basilar artery occlusion, who have a markedly increased risk of death or severe disability. Despite EVT treatment, more than three-quarters of these patients remain dead or functionally dependent at 90 days, indicating substantial room for improvement. Successful recanalization and restoration of effective cerebral perfusion are critical for achieving favorable outcomes. However, although recanalization rates exceed 80% with current thrombectomy techniques, fewer than 40 of patients achieve good functional outcomes at 90 days, suggesting a high incidence of futile recanalization. The underlying mechanisms may include no-reflow, reperfusion injury, and microcirculatory dysfunction, all of which are closely associated with post-recanalization neuroinflammation. Minocycline is a second-generation tetracycline with pleiotropic neuroprotective properties, including inhibition of microglial activation, reduction of inflammatory mediators, suppression of matrix metalloproteinases, attenuation of oxidative stress, and preservation of blood-brain barrier integrity. Preclinical and clinical studies suggest that minocycline may improve neurological outcomes in patients with AIS. This study is a multicenter, prospective, double-blind, randomized controlled trial designed to evaluate the safety and efficacy of adjunctive minocycline in patients with acute posterior circulation arterial occlusion who achieve successful recanalization after EVT. The trial will assess whether early administration of minocycline improves functional outcomes and reduces the incidence of futile recanalization.

This is a multicenter, randomized, double-blind, sham-controlled trial, to determine the efficacy and safety of cTBS in treating patients with acute ischemic stroke after endovascular treatment.

The purpose of this study is to determine the efficacy and safety of plasma adsorption for patients of acute ischemic stroke who underwent endovascular thrombectomy due to large vessel occlusion of anterior circulation.

To Evaluate the Safety and Efficacy of the Super-Bore 8/7F Thrombosis Aspiration Catheter in the Treatment of Acute Intracranial Large Vessel Occlusion.

Acute ischemic stroke (AIS) caused by intracranial large vessel occlusion (LVO) in the anterior circulation significantly contributes to stroke-related disability and mortality. Recent randomized controlled trials have demonstrated substantial benefits of endovascular thrombectomy (EVT) when patients are appropriately triaged beforehand. However, accurately orienting the 'missed segment' during EVT remains challenging. Guide-wires often fail to navigate through the occlusion or are mistakenly directed into the small tranches or even cause vessel rupture. To address this clinical need, the investigators developed an artificial intelligence (AI) algorithm to automate the reconstruction of CT angiography (CTA), focusing on the occluded LVO segment. To evaluate the clinical utility of this AI algorithm, the investigators propose a prospective, stepped-wedge cluster-randomized study to determine whether integrating our AI algorithm into AIS care flow can reduce the time for first pass of the thrombus by improving the visualization of the occluded segment on CTA. Physicians will assess patient eligibility for thrombectomy, and all selected patients will receive standard care according to current guidelines. This approach is expected to enhance patient treatment outcomes for endovascular thrombectomy by leveraging readily available data.

Rationale: Distal Medium Vessel Occlusion (MeVO) are thought to cause as many as 25% to 40% of all acute ischemic strokes (AIS). Despite their relatively high frequency, there is no consensus regarding the optimal management of these patients. However, the fact that AIS related to MeVO often results in significant disability despite best medical treatment (including intravenous thrombolysis, IVT) calls for novel treatment approaches. Fortunately, a growing number of non-randomized studies have now been published demonstrating the feasibility of endovascular treatment (EVT) for MeVO strokes. These studies have demonstrated that distal EVT leads to high rates of successful reperfusion and may be performed with a comparable safety profile to that of EVT for proximal arterial occlusions. Therefore, a strong rational exists to test the safety and efficacy of EVT for MeVO stokes in a prospective randomized clinical trial. Objectives: The primary objective of this study is to evaluate the hypothesis that endovascular thrombectomy is superior to standard medical management in achieving more favorable outcomes according to the modified Rankin Scale scores at 90 days in subjects presenting with acute ischemic stroke related to a distal medium vessel occlusion within 24 hours from symptom onset (defined as time last know well, TLKW). Secondary objectives include the assessment of the cost-effectiveness of endovascular thrombectomy in the medium vessel occlusion (MeVO) population as well as its impact on health-related quality of life. Study design: The study is a prospective, multicenter, investigational, randomized, controlled, open-label study with blinded endpoint evaluation (PROBE design) and an adaptive design with population enrichment. Study population: Subjects presenting with acute ischemic stroke within 24 hours from TLKW and whose strokes are attributable to a distal medium vascular occlusion defined as co/non-dominant M2 segment or M3 segment of the MCA, the ACA (A1, A2, or A3 segments), or the PCA (P1, P2 or P3 segments) with evidence of salvageable brain tissue on perfusion imaging, M2 segment vessel diameter should not exceed 2.0 mm. Primary outcome: Shift in distribution of all levels of the 90-day the modified Rankin Scale with levels 5-6 combined (mRS; 0, 1, 2, 3, 4, 5-6) as assessed by structured assessment.

Studies from our lab indicated that long-term sedation is protective in mice with midbrain infarct. To assess whether post-operative sedation has protective effects on clinical outcomes in patients with ischemic stroke undergoing endovascular thrombectomy (ET), a multi-center, randomized clinical trial will be carried out (POSET study). In POSET study, patients receiving ET for acute ischemic stroke under general anesthesia will be randomly assigned to the control group (Con group) and the post-operative sedation group (POS group). Patients in the Con group will be recovered and extubated immediately after the surgery, whereas those in the POS group will be sedated with propofol and dexmedetomidine for another 6hrs before extubation. The primary endpoint is the score on the modified Rankin Scale assessed at 90±7 days after randomization. The hypothesis is that patients in the POS group will have improved clinical outcome in 3 months after surgery.

We will conduct a multicenter, prospective, randomized, open-label, blinded endpoint trial with a non-inferiority design in patients who present 6 to 24 hours after symptom onset with LVO. Patients who meet eligibility criteria will be randomly assigned to the Non-perfusion or Perfusion group with a 1:1 ratio. In the Non-perfusion group, patients with penumbra-core mismatch (defined as the FLAIR Vascular Hyperintensity (FVH) extending beyond the boundary of the DWI cortical lesions) will receive EVT. In the Perfusion group, patients with perfusion mismatch (defined as regional cerebral blood flow (\<30%) \< 70 ml with mismatch ratio ≥ 1.8 and mismatch volume ≥ 15 ml) will receive EVT. Patients in both groups will receive guideline-based medical treatment. If patients in both groups do not meet the criteria for EVT, only guideline-based medical treatment will be administered.

The objective of this study is to create a comprehensive, multi-center, TRACK-LVO registry-linked cohort of consecutive patients with acute ischemic stroke (AIS) caused by large vessel occlusions (LVO) and presenting to each participating center beyond 24 hours from last known well, who are treated with either endovascular therapy (EVT) or the best available medical management (BMM).

Patients with ischemic stroke in the posterior circulation continue to have high rates of mortality and disability, even with aggressive treatment. We wanted to evaluate preoperative imaging to screen patients with a good prognosis from mechanical embolization. We assess the degree of ischemia by defining the pons-midbrain-medulla index (PMMI) and correlate the preoperative PMMI with the clinical prognosis of postoperative patients to verify the validity of PMMI in predicting the clinical prognosis of patients with embolization.