Endovascular Therapy Is Effective and Safe for Patients With Severe Ischemic Stroke: Pooled Analysis of Interventional Management of Stroke III and Multicenter Randomized Clinical Trial of Endovascular Therapy for Acute Ischemic Stroke in the Netherlands Data

Nomogram established on account of Lasso-logistic regression for predicting hemorrhagic transformation in patients with acute ischemic stroke after endovascular thrombectomy

BACKGROUND

Hemorrhagic transformation (HT) is a common and serious complication in patients with acute ischemic stroke (AIS) after endovascular thrombectomy (EVT). This study was performed to determine the predictive factors associated with HT in stroke patients with EVT and to establish and validate a nomogram that combines with independent predictors to predict the probability of HT after EVT in patients with AIS.

METHODS

All patients were randomly divided into development and validation cohorts at a ratio of 7:3. The least absolute shrinkage and selection operator (LASSO) regression was used to select the optimal factors, and multivariate logistic regression analysis was used to build a clinical prediction model. Calibration plots, decision curve analysis (DCA) and receiver operating characteristic curve (ROC) were generated to assess predictive performance.

RESULTS

LASSO regression analysis showed that Alberta Stroke Program Early CT Scores (ASPECTS), international normalized ratio (INR), uric acid (UA), neutrophils (NEU) were the influencing factors for AIS with HT after EVT. A novel prognostic nomogram model was established to predict the possibility of HT with AIS after EVT. The calibration curve showed that the model had good consistency. The results of ROC analysis showed that the AUC of the prediction model established in this study for predicting HT was 0.797 in the development cohort and 0.786 in the validation cohort.

CONCLUSION

This study proposes a novel and practical nomogram based on ASPECTS, INR, UA, NEU, which can well predict the probability of HT after EVT in patients with AIS.

Intracarotid Infusion of Redox-Active Manganese Porphyrin, MnTnBuOE-2-PyP5+, following Reperfusion Improves Long-Term, 28-Day Post-Stroke Outcomes in Rats

Endovascular mechanical thrombectomy, combined with a tissue plasminogen activator (t-PA), is efficacious as a standard care for qualifying ischemic stroke patients. However, > 50% of thrombectomy patients still have poor outcomes. Manganese porphyrins, commonly known as mimics of superoxide dismutases, are potent redox-active catalytic compounds that decrease oxidative/nitrosative stress and in turn decrease inflammatory responses, mitigating therefore the secondary injury of the ischemic brain. This study investigates the effect of intracarotid MnTnBuOE-2-PyP5+ (BMX-001) administration on long-term, 28-day post-stroke recovery in a clinically relevant setting. The 90 min of transient middle cerebral artery occlusion was performed in young, aged, male, female, and spontaneous hypertension rats. All physiological parameters, including blood pressure, blood gas, glucose, and temperature, were well controlled during ischemia. Either BMX-001 or a vehicle solution was infused through the carotid artery immediately after the removal of filament, mimicking endovascular thrombectomy, and was followed by 7 days of subcutaneous injection. Neurologic deficits and infarct volume were assessed at 28 days in a blinded manner. The effects of BMX-001 on the carotid arterial wall and blood-brain barrier permeability and its interaction with t-PA were assessed in normal rats. There were no intra-group differences in physiological variables. BMX-001-treated stroke rats regained body weight earlier, performed better in behavioral tests, and had smaller brain infarct size compared to the vehicle-treated group. No vascular wall damage and blood-brain barrier permeability changes were detected after the BMX-001 infusion. There was no drug interaction between BMX-001 and t-PA. Intracarotid BMX-001 infusion was safe, and it significantly improved stroke outcomes in rats. These findings indicate that BMX-001 is a candidate drug as an adjunct treatment for thrombectomy procedure to further improve the neurologic outcomes of thrombectomy patients. This study warrants further clinical investigation of BMX-001 as a new stroke therapy.

Efficacy and Safety of Mechanical Thrombectomy in Elderly and Non-Elderly Patients with Large Vessel Occlusion Stroke: Systematic Review and Meta-Analysis

INTRODUCTION

Mechanical thrombectomy (MT) is recommended for large vessel occlusion (LVO) stroke. However, most of the studies that investigated the superiority of MT over best medical management (BMM) alone included preponderantly non-elderly patients. Thus, there is uncertainty in relation to the efficacy of MT in the elderly. We aim to compare the effect of BMM to BMM plus MT among elderly and non-elderly patients with LVO.

METHODS

We performed a systematic search of medical databases from inception to April 2023 to identify randomized studies that reported the functional outcome at 90 days by age for patients with LVO treated with MT versus BMM. Patients were divided into elderly (>70 or >80 years, depending on the cutoff used in each study) and non-elderly. Outcomes were defined as excellent (modified Rankin Scale [mRS] ≤1), good (mRS ≤3), poor (mRS ≥5), or death. Effect sizes were calculated by using random effects meta-analyses. Results were represented by odds ratio (OR) and their 95% confidence intervals (95% CIs).

RESULTS

A total of 2,195 patients were included in the analysis (≥70 years, 7 trials, n = 696; ≥80 years, 2 trials, n = 139). Non-elderly patients treated with MT had higher odds of excellent outcome (OR: 3.05; 95% CI: 2.23-4.18) and good outcome (OR: 2.70; 95% CI: 1.94-3.74), and lower odds of poor outcome (OR: 0.54; 95% CI: 0.40-0.72) and death (OR: 0.63; 95% CI: 0.41-0.96). Similarly, elderly patients treated with MT had higher odds of excellent (OR: 2.39; 95% CI: 1.05-5.45) and good outcomes (OR: 2.18; 95% CI: 1.43-3.33) and lower odds of poor outcome (OR: 0.48; 95% CI: 0.33-0.70) and mortality (OR: 0.50; 0.26-0.95). When outcomes were analyzed by age subgroups, MT was associated with higher odds of good outcome in patients ≥70 years (OR: 1.95, 95% CI: 1.26-3.03) and ≥80 years (OR: 4.43, 95% CI: 1.02-19.23).

CONCLUSION

MT increases the likelihood of achieving a good outcome in elderly and non-elderly patients without increasing the risk of severe disability or death. MT, when otherwise clinically indicated, should be considered over BMM alone in both age groups.

Emergent carotid stenting versus no stenting for acute ischemic stroke due to tandem occlusion: a meta-analysis

BACKGROUND

Emergent carotid artery stenting (eCAS) is performed during mechanical thrombectomy for acute ischemic stroke due to tandem occlusion. However, the optimal management strategy in this setting is still unclear.

OBJECTIVE

To carry out a systematic review and meta-analysis to investigate the safety and efficacy of eCAS in patients with tandem occlusion.

METHODS

Systematic review followed the PRISMA guidelines. Medline, EMBASE, and Scopus were searched from January 1, 2004 to March 7, 2022 for studies evaluating eCAS and no-stenting approach in patients with stroke with tandem occlusion. Primary endpoint was the 90-day modified Rankin Scale score 0-2; secondary outcomes were (1) symptomatic intracerebral hemorrhage (sICH), (2) recurrent stroke, (3) successful recanalization (Thrombolysis in Cerebral Infarction score 2b-3), (4) embolization in new territories, and (5) restenosis rate. Meta-analysis was performed using the Mantel-Haenszel method and random-effects modeling.

RESULTS

Forty-six studies reached synthesis. eCAS was associated with higher good functional outcome compared with the no-stenting approach (OR=1.52, 95% CI 1.19 to 1.95), despite a significantly increased risk of sICH (OR=1.97, 95% CI 1.23 to 3.15), and higher successful recanalization rate (OR=1.91, 95% CI 1.29 to 2.85). Restenosis rate was lower in the eCAS group than in the no-stenting group (2% vs 9%, p=0.001). Recanalization rate was higher in retrograde than antegrade eCAS (OR=0.51, 95% CI 0.28 to 0.93). Intraprocedural antiplatelets during eCAS were associated with higher rate of good functional outcome (60% vs 46%, p=0.016) and lower rate of sICH (7% vs 11%; p=0.08) compared with glycoprotein IIb/IIIa inhibitors.

CONCLUSIONS

In observational studies, eCAS seems to be associated with higher good functional outcome than no-stenting in patients with acute ischemic stroke due to tandem occlusion, despite the higher risk of sICH. Dedicated trials are needed to confirm these results.

Recanalization Rate and Clinical Outcomes of Intravenous Tissue Plasminogen Activator Administration for Large Vessel Occlusion Stroke Patients

OBJECTIVE

Stroke caused from large vessel occlusion (LVO) has emerged as the most common stroke subtype worldwide. Intravenous tissue plasminogen activator administration (IV-tPA) and additional intraarterial thrombectomy (IA-Tx) is regarded as standard treatment. In this study, the authors try to find the early recanalization rate of IV-tPA in LVO stroke patients.

METHODS

Total 300 patients undertook IA-Tx with confirmed anterior circulation LVO, were analyzed retrospectively. Brain computed tomography angiography (CTA) was the initial imaging study and acute stroke magnetic resonance angiography (MRA) followed after finished IV-tPA. Early recanalization rate was evaluated by acute stroke MRA within 2 hours after the IV-tPA. In 167 patients undertook IV-tPA only and 133 non-recanalized patients by IV-tPA, additional IA-Tx tried (IV-tPA + IA-Tx group). And 131 patients, non-recanalized by IV-tPA (IV-tPA group) additional IA-Tx recommend and tried according to the patient condition and compliance.

RESULTS

Early recanalization rate of LVO after IV-tPA was 12.0% (36/300). In recanalized patients, favorable outcome (modified Rankin Scale, 0-2) was 69.4% (25/36) while it was 32.1% (42/131, p<0.001) in non-recanalized patients. Among 133 patients, nonrecanalized after intravenous recombinant tissue plasminogen activator and undertook additional IA-Tx, the clinical outcome was better than not undertaken additional IA-Tx (favorable outcome was 42.9% vs. 32.1%, p=0.046). Analysis according to the perfusion/diffusion (P/D)-mismatching or not, in patient with IV-tPA with IA-Tx (133 patients), favorable outcome was higher in P/ D-mismatching patient (52/104; 50.0%) than P/D-matching patients (5/29; 17.2%; p=0.001). Which treatment tired, P/D-mismatching was favored in clinical outcome (iv-tPA only, p=0.008 and IV-tPA with IA-Tx, p=0.001).

CONCLUSION

The P/D-mismatching influences on the recanalization and clinical outcomes of IV-tPA and IA-Tx. The authors would like to propose that we had better prepare IA-Tx when LVO is diagnosed on initial diagnostic imaging. Furthermore, if the patient shows P/D-mismatching on MRA after IV-tPA, additional IA-Tx improves treatment results and lessen the futile recanalization.

Thrombectomy in basilar artery occlusion

BACKGROUND AND PURPOSE

The benefit of thrombectomy (TE) for acute ischemic stroke (AIS) in patients suffering basilar artery occlusion (BAO) is still unclear. Our aim was to analyze functional outcome after 3 months in BAO compared to anterior circulation large vessel occlusion (ACLVO) in a nationwide registry.

METHODS

Patients enrolled into the Austrian Endostroke Registry from 2013 to 2018 were analyzed. We used propensity score matching to control for imbalances and to compare patients with BAO and ACLVO. The primary outcome was favorable functional outcome after 3 months measured by the modified Rankin Scale (mRS) (0-2). Multivariate models were applied to estimate the effect of localization (BAO vs ACLVO).

RESULTS

In total, 2288 patients underwent TE for AIS with proximal vessel occlusion, of these 267 with BAO. Two hundred and sixty-four patients with BAO were matched to 264 patients with ACLVO. Baseline characteristics were well-balanced. The 90-day mortality did not significantly differ between patients with BAO and ACLVO. In a multivariate logistic regression model, we did not detect a significant difference in functional outcome between BAO and ACLVO (odds ratio for favorable outcome defined as mRS = 0-2: 1.19; 95% confidence interval (CI) = 0.78-1.81; p = 0.42). In patients with an onset-to-door-time ⩾270 min, TE of BAO was associated with poor functional outcome defined as mRS 3-6 (odds ratio (OR) = 3.97; 95% CI = 1.32-11.94; p = 0.01) as compared to ACLVO.

CONCLUSION

In this study, functional outcome did not differ after TE in patients with BAO and ACLVO overall; however, we detected an association of BAO with poor outcome in patients arriving late.

Safety and outcomes of endovascular treatment in patients with very severe acute ischemic stroke

BACKGROUND

Patients with anterior circulation ischemic strokes due to large vessel occlusion (AIS-LVO) and very severe neurological deficits (National Institutes of Health Stroke Scale (NIHSS) score > 25) were under-represented in clinical trials on endovascular treatment (EVT). We aimed to evaluate safety and outcomes of EVT in patients with very severe vs. severe (NIHSS score 15-25) neurological deficits.

METHODS

We included consecutive patients undergoing EVT for AIS-LVO between January 2015 and December 2019 at Lille University Hospital. We compared rates of parenchymal hemorrhage (PH), symptomatic intracranial hemorrhage (SICH), procedural complications, and 90-day mortality between patients with very severe vs. severe neurological deficit using univariable and multivariable logistic regression analyses. Functional outcome (90-days modified Rankin Scale) was compared between groups using ordinal logistic regression analysis.

RESULTS

Among 1484 patients treated with EVT, 108 (7%) had pre-treatment NIHSS scores > 25, 873 (59%) with NIHSS scores 15-25 and 503 (34%) with NIHSS scores < 15. Rates of PH, SICH, successful recanalization, and procedural complications were similar in patients with NIHSS scores > 25 and NIHSS 15-25. Patients with NIHSS > 25 had a lower likelihood of improved functional outcome (_adjcommon OR 0.31[95% CI 0.21-0.47]) and higher odds of mortality at 90 days (_adjOR 2.3 [95% CI 1.5-3.7]) compared to patients with NIHSS 15-25. Successful recanalization was associated with better functional outcome (_adjcommon OR 3.8 [95% CI 1.4-10.4]), and lower odds of mortality (_adjOR 0.3 [95% CI 0.1-0.9]) in patients with very severe stroke. The therapeutic effect of recanalization on functional outcome and mortality was similar in both groups.

CONCLUSIONS

In patients with very severe neurological deficit, EVT was safe and successful recanalization was strongly associated with better functional outcome at 90 days.

Use of emerging technologies to enhance the treatment paradigm for spontaneous intraventricular hemorrhage

The presence of intraventricular hemorrhage (IVH) portends a worse prognosis in patients presenting with spontaneous intracerebral hemorrhage (ICH). Intraventricular hemorrhage increases the rates of hydrocephalus, ventriculitis, and long-term shunt dependence. Over the past decade, novel medical devices and protocols have emerged to directly treat IVH. Presently, we review new technological adaptations to treating intraventricular hemorrhage in an effort to focus further innovation in treating this morbid neurosurgical pathology. We summarize current and historical treatments as well as innovations in IVH including novel procedural techniques, use of the Integra Surgiscope, use of the Artemis evacuator, use of BrainPath, novel catheter technology, large bore external ventricular drains, the IRRAflow, the CerebroFlo, and the future directions of the field. Technology and medical devices for both surgical and nonsurgical methods are advancing the treatment of IVH. With many promising new technologies on the horizon, prospects for improved clinical care for IVH and its etiologies remain hopeful.

Oleuropein Protects Against Cerebral Ischemia Injury in Rats: Molecular Docking, Biochemical and Histological Findings

This study was designed to evaluate the underlying protective mechanisms of oleuropein involved in alleviating brain damage in a rat model of ischemic stroke. Male Wistar rats were divided into four groups; Control, stroke (MCAO), MCAO + clopidogrel (Clop) and MCAO + oleuropein (Ole). Results showed that the MCAO group evidenced significant brain edema (+ 9%) as well as increases of plasma cardiac markers such as lactate deshydrogenase (LDH), creatine kinase (CK-MB), fibrinogen and Trop-T by 11 %, 43%, 168 and 590%, respectively, as compared to the control group. Moreover, infarcted rats exhibited remarkable elevated levels of angiotensin converting enzyme (ACE), both in plasma and brain tissue, with astrocyte swelling and necrotic neurons in the infarct zone, hyponatremia, and increased rate of thiobarbituric acid-reactive substances (TBARS) by 89% associated with decreases in the activity of superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (Cat) by 51%, 44 and 42%, respectively, compared to normal control rats. However, MCAO rats treated with oleuropein underwent mitigation of cerebral edema, correction of hyponatremia, remarkable decrease of plasma fibrinogen and cardiac dysfunctional enzymes, inhibition of ACE activity and improvement of oxidative stress status in brain tissue. Furthermore, in silico analysis showed considerable inhibitions of ACE, protein disulfide isomerase (PDI) and TGF-β1, an indicative of potent anti-embolic properties. Overall, oleuropein offers a neuroprotective effect against ischemic stroke through its antioxidative and antithrombotic activities.

Management of Internal Carotid Artery and Intracranial Anterior Circulation Tandem Occlusion with Stenting versus No Stenting: A Multicenter Study

BACKGROUND

Tandem occlusion (TO) describes not only occlusion of the middle cerebral artery but a contemporaneous occlusion of the cervical internal carotid artery. There is a paucity of data over whether mechanical thrombectomy (MT) alone, MT with angioplasty, or MT with carotid artery stent placement is superior. We aim to address a gap in the literature comparing carotid stenting with mechanical thrombectomy (CSMT) and carotid angioplasty with mechanical thrombectomy (CAMT) in patients presenting with acute anterior circulation TOs.

METHODS

This is a multicenter, retrospective study from 2012 to 2020 comparing CSMT and CAMT presenting with acute anterior circulation TOs. Primary outcomes of interest were functional status, perioperative stroke, mortality, and symptomatic intracranial hemorrhage (sICH). A total of 92 patients (66 vs. 26 in CSMT and CAMT, respectively) met inclusion criteria for analysis.

RESULTS

There was no statistically significant difference in functional outcomes at 90-day follow-up (adjusted odds ratio [aOR] 0.82; 95% confidence interval [CI] 0.20-3.5; P = 0.46). In addition, there was no statistically significant difference in 90-day mortality (aOR 0.361; 95% CI 0.016-2.92; P = 0.532) and perioperative stroke rate (aOR 1.76; 95% CI 0.160-15.6; P = 0.613). However, sICH risk was significantly greater in the stent-treated cohort (aOR 3.94; 95% CI 0.529-37.4; P = 0.003).

CONCLUSIONS

Functional outcomes, mortality, and perioperative stroke rates do not significantly differ in CSMT and CAMT procedures in the acute setting. However, CSMT-treated patients do appear to have an increased risk of sICH, potentially due to the use of additional antiplatelet agents following stent placement.

Effect of Blood Pressure Management Strategies on Outcomes in Patients with Acute Ischemic Stroke After Successful Mechanical Thrombectomy

BACKGROUND

Variability, with no general consensus, exists in how patients' blood pressure should be managed after successful mechanical thrombectomy (MT) for large vessel ischemic stroke. We examined whether exceeding the systolic blood pressure (SBP) targets in patients during the first 24 hours after successful MT led to worse outcomes.

METHODS

We retrospectively studied a consecutive sample of adult patients who had undergone MT. We collected SBP data for the first 24 hours after MT and categorized the patients into 3 groups according to cases of the SBP exceeding 140, 160, or 180 mm Hg. The primary and secondary outcomes were the modified Rankin scale score at discharge and 90 days of follow-up, the incidence of symptomatic intracranial hemorrhage, malignant cerebral edema, and hemicraniectomy, mortality within 90 days, and discharge disposition.

RESULTS

A total of 117 patients were included (mean age, 65 ± 13.12 years; 53% female). The occurrence of ≥1 instance of SBP ≥180 mm Hg was significantly associated with poor functional outcomes at discharge (adjusted odds ratio [OR], 5.83; 95% confidence interval [CI], 1.41-32.9; P = 0.025) but not at 90 days of follow-up. The occurrence of SBP ≥160 mm Hg resulted in an independently increased odds of malignant cerebral edema (adjusted OR, 17.07; 95% CI, 2.56-174.4; P = 0.01), with a trend toward increased odds of symptomatic intracranial hemorrhage (adjusted OR, 4.42; 95% CI, 1.03-21.2; P = 0.0503).

CONCLUSIONS

These results suggest that individual instances of SBP elevation alone after successful MT, rather than a necessarily prolonged increased blood pressure as reflected by the mean or median SBP values, can significantly affect the clinical outcomes after successful MT.

Mechanical thrombectomy in patients with proximal occlusions and low NIHSS: Results from a large prospective registry

BACKGROUND

Mechanical thrombectomy is now standard of care for treatment of acute ischemic stroke secondary to large vessel occlusion in the setting of high NIHSS. We analysed a large nationwide registry focusing on patients with large vessel occlusion and low NIHSS on admission to evaluate the efficacy and safety of thrombectomy in this patient population METHODS: 2826 patients treated with mechanical thrombectomy were included in a multicentre registry from January 1, 2011 to December 31, 2015. We included patients with large vessel occlusion and NIHSS ≤ 6 on admission. Baseline characteristics, imaging, clinical outcome, procedure adverse events and positive and negative outcome predictors were analysed.

RESULTS

134 patients were included. 90/134 had an anterior circulation and 44 a posterior circulation stroke. One patient died before treatment. Successful revascularization (mTICI 2b-3) was achieved in 73.7% (98/133) of the patients. Intraprocedural adverse event was observed in 3% (4/133) of cases. Symptomatic intracranial haemorrhage rate was 5.3% (7/133). At three months, 70.9% (95/134) of the patients had mRS score 0-2, 15.7% (21/134) mRS 3-5 and 13.4% (18/134) mRS 6. Age and successful recanalization were significant predictors of a good clinical outcome on both univariate (p= 0.005 and p=0.007) and multivariable (p=0.0018 and p=0.009 [nat log]) analysis. Absence of vessel recanalization and symptomatic intracranial hemorrhage were independent predictors of poor outcome (p=0.021) .

CONCLUSIONS

Our study suggests that patients with large vessel occlusion and low NIHSS score on admission can benefit from mechanical thrombectomy. Randomized trials are warranted.

Salidroside as a potential neuroprotective agent for ischemic stroke: a review of sources, pharmacokinetics, mechanism and safety

Salidroside (Sal) is a bioactive extract principally from traditional herbal medicine such as Rhodiola rosea L., which has been commonly used for hundreds of years in Asia countries. The excellent neuroprotective capacity of Sal has been illuminated in recent studies. This work focused on the source, pharmacokinetics, safety and anti-ischemic stroke (IS) effect of Sal, especially emphasizing its mechanism of action and BBB permeability. Extensive databases, including Pubmed, Web of science (WOS), Google Scholar and China National Knowledge Infrastructure (CNKI), were applied to obtain relevant online literatures. Sal exerts powerful therapeutic effects on IS in experimental models either in vitro or in vivo due to its neuroprotection, with significantly diminishing infarct size, preventing cerebral edema and improving neurological function. Also, the findings suggest the underlying mechanisms involve anti-oxidation, anti-inflammation and anti-apoptosis by regulating multiple signaling pathways and key molecules, such as NF-κB, TNF-α and PI3K/Akt pathway. In pharmacokinetics, although showing a rapid absorption and elimination, bioavailability of Sal is elevated under some non-physiological conditions. The component and its metabolite (tyrosol) are capable of distributing to brain tissue and the later keeps a higher level of concentration. Moreover, Sal scarcely has obvious toxicity or side effects in a variety of animal experiments and clinical trials, but combination of drugs and perinatal use of medicine should be taken more attentions. Finally, as an active ingredient, not only is Sal isolated from diverse plants with limited yield, but also large batches of the products can be harvested by biological and chemical synthesis. With higher efficacy and better safety profiles, Sal could sever as a promising neuroprotectant for preventing and treating IS. Nevertheless, further investigations are still required to explore the pharmacodynamic and pharmacokinetic properties of Sal in the treatment of IS.

Antioxidant nanomedicine with cytoplasmic distribution in neuronal cells shows superior neurovascular protection properties

This study investigated whether nitroxide radical (4-amino-TEMPOL)-containing nanoparticles (RNPs; antioxidant nanomedicine) can prevent neurovascular unit impairment caused by reactive oxygen species (ROS) after cerebral ischemia-reperfusion. C57BL/6J mice underwent transient middle cerebral artery occlusion (tMCAO). The mice were randomly divided and administered intra-arterial RNPs injection (9 mg/kg, 7 μM/kg), edaravone (3 mg/kg, 17 μM/kg), or phosphate-buffered saline (control group). Survival rate and neurological score were evaluated 24 h post-injection. RNPs distribution was determined using immunofluorescence staining and blood-brain barrier (BBB) disruption using Evans blue extravasation assay. Effect of RNPs and edaravone on microglia polarization into microglia M1 and M2 was evaluated. We also determined multiple ROS-scavenging activities in brain homogenates of RNPs- and edaravone-treated animals using an electron spin resonance-based spin-trapping method. Compared with edaravone, RNPs significantly improved the survival rate and neurological deficit, inhibited BBB disruption and supported polarization of microglia into M2 microglia. RNPs were localized in endothelial cells, the perivascular space, neuronal cell cytoplasm, astrocytes, and microglia. Scavenging capacities of hydroxyl, alkoxyl, and peroxyl radicals were significantly higher in the RNPs-treated group. RNPs show promising results as a future neuroprotective nanomedicine approach for cerebral ischemia-reperfusion injury.

Impact of endovascular recanalization on quantitative lesion water uptake in ischemic anterior circulation strokes

Studies evaluating the effect of reperfusion on ischemic edema in acute stroke described conflicting results. Net water uptake (NWU) per brain volume is a new quantitative imaging biomarker of space-occupying ischemic edema, which can be measured in computed tomography (CT). We sought to investigate the effects of vessel recanalization on the formation of ischemic brain edema using quantitative NWU. In this multicenter observational study, acute ischemic stroke patients with a large vessel occlusion (LVO) in the anterior circulation were consecutively screened. Patients with vessel recanalization (thrombolysis in cerebral infarction (TICI) 2 b or 3) versus persistent vessel occlusion (no thrombectomy, TICI 0-1) were compared. Lesion-NWU was quantified in multimodal admission CT and follow-up CT (FCT), and ΔNWU was calculated as difference. Of 194 included patients, 150 had successful endovascular recanalization and 44 persistent LVO. In FCT after treatment, the mean (standard deviation) ΔNWU was 15.8% (5.7) in patients with persistent LVO and 9.8% (5.8) with vessel recanalization (p < 0.001). In multivariate regression analysis, vessel recanalization was independently associated with a lowered ΔNWU by 6.3% compared to LVO (95% confidence interval: 3.7-9.0, p < 0.001). Successful vessel recanalization was associated with a significantly reduced formation of ischemic brain edema. Quantitative NWU may be used to compare the treatment effects in acute stroke.

Oxidative stress-responsive apoptosis inducing protein (ORAIP) plays a critical role in cerebral ischemia/reperfusion injury

Oxidative stress is known to play a critical role in the pathogenesis of various disorders, especially in ischemia/reperfusion (I/R) injury. We identified an apoptosis-inducing humoral factor and named this novel post translationally modified secreted form of eukaryotic translation initiation factor 5A (eIF5A) "oxidative stress-responsive apoptosis inducing protein" (ORAIP). The purpose of this study was to investigate the role of ORAIP in the mechanisms of cerebral I/R injury. Hypoxia/reoxygenation induced expression of ORAIP in cultured rat cerebral neurons, resulting in extensive apoptosis of these cells, which was largely suppressed by neutralizing anti-ORAIP monoclonal antibody (mAb) in vitro. Recombinant-ORAIP induced extensive apoptosis of cerebral neurons. Cerebral I/R induced expression of ORAIP in many neurons in a rat tandem occlusion model in vivo. In addition, we analyzed the effects of intracerebroventricular administration of neutralizing anti-ORAIP mAb on the development of cerebral infarction. Cerebral I/R significantly increased ORAIP levels in cerebrospinal fluid. Treatment with intracerebroventricular administration of neutralizing anti-ORAIP mAb reduced infarct volume by 72%, and by 55% even when started after reperfusion. These data strongly suggest that ORAIP plays a pivotal role and will offer a critical therapeutic target for cerebral I/R injury induced by thrombolysis and thrombectomy for acute ischemic stroke.

Platelets Are at the Nexus of Vascular Diseases

Platelets are important actors of cardiovascular diseases (CVD). Current antiplatelet drugs that inhibit platelet aggregation have been shown to be effective in CVD treatment. However, the management of bleeding complications is still an issue in vascular diseases. While platelets can act individually, they interact with vascular cells and leukocytes at sites of vascular injury and inflammation. The main goal remains to better understand platelet mechanisms in thrombo-inflammatory diseases and provide new lines of safe treatments. Beyond their role in hemostasis and thrombosis, recent studies have reported the role of several aspects of platelet functions in CVD progression. In this review, we will provide a comprehensive overview of platelet mechanisms involved in several vascular diseases.

Futile reperfusion and predicted therapeutic benefits after successful endovascular treatment according to initial stroke severity

Background

Futile reperfusion (poor functional status despite successful reperfusion) was observed in up to 67% of patients enrolled in recent endovascular treatment (EVT) clinical trials. We investigated the impact of baseline stroke severity on both futile reperfusion and therapeutic benefit of successful EVT.

Methods

Using a prospective multicenter stroke registry, we identified consecutive ischemic stroke patients with anterior circulation large artery occlusion, who were reperfused successfully by EVT (Thrombolysis in Cerebral Infarction grade 2b–3). The rate of futile reperfusion was assessed across the initial National Institutes of Health Stroke Scale (NIHSS) scores. The frequency of poor outcomes (modified Rankin scale [mRS] 3–6) according to NIHSS scores was compared between patients revascularized successfully by EVT and those who did not receive EVT, after standardizing for age.

Results

Among 21,591 patients with ischemic stroke, 972 (4.5%) received EVT within 12 h of onset, including 440 who met study eligibility criteria. Futile reperfusion was observed in 226 of the 440 study-eligible patients (51.4%) and was associated with stroke severity: 20.9% in NIHSS scores ≤5, 34.6% in 6–10, 58.9% in 11–20, and 63.8% in > 20 (p < 0.001). Nonetheless, the therapeutic benefit of EVT also increased with increasing stroke severity (p for interaction < 0.001): 0.1% in NIHSS ≤5, 18.6% in 6–10, 28.7% in 11–20, and 34.3% in > 20.

Conclusions

EVT is more beneficial with increasing stroke severity, although futile reperfusion also increases with higher stroke severity.

Electronic supplementary material

The online version of this article (10.1186/s12883-019-1237-2) contains supplementary material, which is available to authorized users.

Calcium Imaging of Microglial Network Activity in Stroke

Calcium signaling plays a significant role in microglial activation. Genetically encoded calcium indicators (GECI) have been widely used for calcium imaging studies in many brain cell types, including neurons, astrocytes, and oligodendrocytes. However, microglial calcium imaging approaches have been hampered by idiosyncrasies of their gene expression and malleable cell properties. The generation of PC::G5-tdT, a Polr2a locus-based conditional mouse reporter of calcium, facilitated the deployment of GECI in microglia. When crossed with the Iba1(Aif1)-IRES-Cre line, all brain microglia of the progeny are labeled with the calcium indicator variant GCaMP5G and the red fluorescent protein tdTomato. This reporter system has enabled in vivo studies of intracellular calcium in large microglial cell populations in cerebral pathologies such as ischemic stroke. In this chapter, we outline specific guidelines for genetic, surgical, imaging, and data analysis aspects of microglial calcium monitoring of the ischemic cortex following middle cerebral artery occlusion.

Neutrophil to lymphocyte ratio predicts intracranial hemorrhage after endovascular thrombectomy in acute ischemic stroke

BACKGROUND

The development of intracranial hemorrhage (ICH) in acute ischemic stroke is associated with a higher neutrophil to lymphocyte ratio (NLR) in peripheral blood. Here, we studied whether the predictive value of NLR at admission also translates into the occurrence of hemorrhagic complications and poor functional outcome after endovascular treatment (EVT).

METHODS

We performed a retrospective analysis of consecutive patients with anterior circulation ischemic stroke who underwent EVT at a tertiary care center from 2012 to 2016. Follow-up scans were examined for non-procedural ICH and scored according to the Heidelberg Bleeding Classification. Demographic, clinical, and laboratory data were correlated with the occurrence of non-procedural ICH.

RESULTS

We identified 187 patients with a median age of 74 years (interquartile range [IQR] 60-81) and a median baseline National Institutes of Health Stroke scale (NIHSS) score of 18 (IQR 13-22). A bridging therapy with recombinant tissue-plasminogen activator (rt-PA) was performed in 133 (71%). Of the 31 patients with non-procedural ICH (16.6%), 13 (41.9%) were symptomatic. Patients with ICH more commonly had a worse outcome at 3 months (p = 0.049), and were characterized by a lower body mass index, more frequent presence of tandem occlusions, higher NLR, larger intracranial thrombus, and prolonged rt-PA and groin puncture times. In a multivariate analysis, higher admission NLR was independently associated with ICH (OR 1.09 per unit increase, 95% CI (1.00-1.20, p = 0.040). The optimal cutoff value of NLR that best distinguished the development of ICH was 3.89.

CONCLUSIONS

NLR is an independent predictor for the development of ICH after EVT. Further studies are needed to investigate the role of the immune system in hemorrhagic complications following EVT, and confirm the value of NLR as a potential biomarker.

Thrombectomy in stroke of unknown onset, wake up stroke and late presentations: Australian experience from 2 comprehensive stroke centres

Two recent randomized controlled trials (RCTs) showed selected patients treated with endovascular thrombectomy (EVT) more than 6 h from acute ischemic stroke (AIS) onset had significant improvement in functional outcome at 90 days compared with standard care alone. Our aim is to determine the outcome and predictors of good outcome in AIS patients undergoing EVT with unknown-onset, or late presentation, stroke after 6 h from time last seen well, or witnessed stroke onset, at two Australian comprehensive stroke centres. A retrospective analysis of functional outcome and mortality at 90-days from a prospective cohort of 56 consecutive patients with unknown-onset, or late presentation, stroke with large vessel occlusion (LVO) in the anterior cerebral circulation undergoing EVT over a 15-month period (2016-2017). We evaluated factors which correlated with good functional outcome defined as a 90-day modified Rankin scale (mRS) 0-2. Recanalization times and symptomatic intracranial haemorrhage (sICH) rates were also examined. A good functional outcome was achieved in 35 patients (62%). Eight patients died (14%). Median time-to-recanalization was 7.6 h. SICH occurred in four patients (7%). Factors which predicted good 90-day functional outcome included baseline National Institutes of Health Stroke Scale (NIHSS) < 16, 24 h NIHSS < 10, baseline Alberta Stroke Program Early CT Score (ASPECTS) ≥ 8, pre-procedural CT perfusion imaging and LVO lesion location. This study shows good 'real world' outcomes, comparable to published RCTs, in patients with unknown-onset, or late presentation, stroke treated with EVT more than 6 h from stroke onset.

Fibrinolysis: strategies to enhance the treatment of acute ischemic stroke

Stroke is a major cause of disability worldwide, and is the second leading cause of death after ischemic heart disease. Until recently, tissue-type plasminogen activator (t-PA) was the only treatment for acute ischemic stroke. If administered within 4.5 h of symptom onset, t-PA improves the outcome in stroke patients. Mechanical thrombectomy is now the preferred treatment for patients with acute ischemic stroke resulting from a large-artery occlusion in the anterior circulation. However, the widespread use of mechanical thrombectomy is limited by two factors. First, only ⁓ 10% of patients with acute ischemic stroke have a proximal large-artery occlusion in the anterior circulation and present early enough to undergo mechanical thrombectomy within 6 h; an additional 9-10% of patients presenting within the 6-24-h time window may also qualify for the procedure. Second, not all stroke centers have the resources or expertise to perform mechanical thrombectomy. Nonetheless, patients who present to hospitals where thrombectomy is not an option can receive intravenous t-PA, and those with qualifying anterior circulation strokes can then be transferred to tertiary stroke centers where thrombectomy is available. Therefore, despite the advances afforded by mechanical thrombectomy, there remains a need for treatments that improve the efficacy and safety of thrombolytic therapy. In this review, we discuss: (i) current treatment options for acute ischemic stroke; (ii) the mechanism of action of fibrinolytic agents; and (iii) potential strategies to manipulate the fibrinolytic system to promote endogenous fibrinolysis or to enhance the efficacy of fibrinolytic therapy.

Does stroke health promotion increase awareness of appropriate behavioural response? Impact of the face, arm, speech and time (FAST) campaign on population knowledge of stroke risk factors, warning signs and emergency response

INTRODUCTION

Inability to identify stroke warning signs accurately is an important cause of delay in seeking medical attention, leading to potential ineligibility for acute intervention. We report on post-campaign findings (wave 2) of national surveys to estimate changes in population knowledge following a media-based Face, Arm, Speech, Time stroke awareness campaign, comparing findings to those of a pre-campaign population survey (wave 1).Participants and methods: One thousand and ten randomly selected adults (18+) completed the Stroke Awareness Questionnaire on knowledge of warning signs, risk factors and response to stroke at wave 2 and findings were compared to wave 1 survey results. Logistic regression was used to examine the association between demographic characteristics and self-reported risk factors with knowledge of stroke and emergency response.

RESULTS

No significant differences existed in the ability of respondents to define stroke or to identify two or more stroke risk factors between waves 1 and 2 surveys (71% and 70%, respectively). Respondents to the wave 2 survey were five times more likely (odds ratio 4.9, p < .001) than those responding at wave 1 to know at least two warning signs of stroke (67% vs. 31%, respectively), specifically those targeted by the Face, Arm, Speech, Time campaign. While significant improvement in intention to call an ambulance was noted (odds ratio 1.5, p < .001, 57% at wave 2 compared to 47% at wave 1), for almost half of respondents (43%) this would not have been their first response to stroke. Less than 5% of respondents to both surveys identified thrombolysis as an emergency treatment for stroke (3.9% at wave 2 compared to 1.8% at wave 1).

DISCUSSION

Although significant improvements were made in several areas of stroke knowledge and intended response, awareness of acute stroke interventions was poor and intended behavioural response was suboptimal.

CONCLUSION

Findings from this study indicate need for targeted campaigns to improve population understanding of the reasons underlying the importance of rapid emergency response to stroke.

European Stroke Organisation certification of stroke units and stroke centres

To improve quality and to overcome the wide discrepancies in stroke care both within- and between European countries, the European Stroke Organisation Executive Committee initiated in 2007 activities to establish certification processes for stroke units and stroke centres. The rapidly expanding evidence base in stroke care provided the mandate for the European Stroke Organisation Stroke Unit-Committee to develop certification procedures for stroke units and stroke centres with the goals of setting standards for stroke treatment in Europe, improving quality and minimising variation. The purpose of this article is to present the certification criteria and the auditing process for stroke units and stroke centres that aim to standardise and harmonise care for stroke patients, and hence become members of the European Stroke Organisation Stroke Unit and Stroke Centre network. Standardised application forms and guidelines for national and international auditors have been developed and updated by members of the European Stroke Organisation Stroke Unit-Committee. Key features are availability of trained personnel, diagnostic equipment, acute treatment and collaboration with other stroke-caregivers. After submission, the application is reviewed by one national and two international auditors. Based on their reports, the Stroke Unit-Committee will make a final decision. Validating on-site visits for a subset of stroke units and stroke centres are planned. We herein describe a novel, European Stroke Organisation-based online certification process of stroke units and stroke centres. This is a major step forward towards high-quality stroke care across Europe. The additional value by connecting high-quality European Stroke Organisation Stroke Unit and Stroke Centre is facilitation of future collaboration and research activities, enabling building and maintenance of a high-quality stroke care network in Europe.

Neurovascular Unit Protection From Cerebral Ischemia-Reperfusion Injury by Radical-Containing Nanoparticles in Mice

BACKGROUND AND PURPOSE

Reperfusion therapy by mechanical thrombectomy is used to treat acute ischemic stroke. However, reactive oxygen species generation after reperfusion therapy causes cerebral ischemia-reperfusion injury, which aggravates cerebral infarction. There is limited evidence for clinical efficacy in stroke for antioxidants. Here, we developed a novel core-shell type nanoparticle containing 4-amino-4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (nitroxide radical-containing nanoparticles [RNPs]) and investigated its ability to scavenge reactive oxygen species and confer neuroprotection.

METHODS

C57BL/6J mice underwent transient middle cerebral artery occlusion and then received RNPs (9 mg/kg) through the common carotid artery. Infarction size, neurological scale, and blood-brain barrier damage were visualized by Evans blue extravasation 24 hours after reperfusion. RNP distribution was detected by rhodamine labeling. Blood-brain barrier damage, neuronal apoptosis, and oxidative neuronal cell damage were evaluated in ischemic brains. Multiple free radical-scavenging capacities were analyzed by an electron paramagnetic resonance-based method.

RESULTS

RNPs were detected in endothelial cells and around neuronal cells in the ischemic lesion. Infarction size, neurological scale, and Evans blue extravasation were significantly lower after RNP treatment. RNP treatment preserved the endothelium and endothelial tight junctions in the ischemic brain; neuronal apoptosis, O₂^- production, and gene oxidation were significantly suppressed. Reactive oxygen species scavenging capacities against OH, ROO, and O₂^- improved by RNP treatment.

CONCLUSIONS

An intra-arterial RNP injection after cerebral ischemia-reperfusion injury reduced blood-brain barrier damage and infarction volume by improving multiple reactive oxygen species scavenging capacities. Therefore, RNPs can provide neurovascular unit protection.

Selection of patients for intra-arterial treatment for acute ischaemic stroke: development and validation of a clinical decision tool in two randomised trials

Objective To improve the selection of patients with acute ischaemic stroke for intra-arterial treatment using a clinical decision tool to predict individual treatment benefit.Design Multivariable regression modelling with data from two randomised controlled clinical trials.Setting 16 hospitals in the Netherlands (derivation cohort) and 58 hospitals in the United States, Canada, Australia, and Europe (validation cohort).Participants 500 patients from the Multicenter Randomised Clinical Trial of Endovascular Treatment for Acute Ischaemic Stroke in the Netherlands trial (derivation cohort) and 260 patients with intracranial occlusion from the Interventional Management of Stroke III trial (validation cohort).Main outcome measures The primary outcome was the modified Rankin Scale (mRS) score at 90 days after stroke. We constructed an ordinal logistic regression model to predict outcome and treatment benefit, defined as the difference between the predicted probability of good functional outcome (mRS score 0-2) with and without intra-arterial treatment.Results 11 baseline clinical and radiological characteristics were included in the model. The externally validated C statistic was 0.69 (95% confidence interval 0.64 to 0.73) for the ordinal model and 0.73 (0.67 to 0.79) for the prediction of good functional outcome, indicating moderate discriminative ability. The mean predicted treatment benefit varied between patients in the combined derivation and validation cohort from -2.3% to 24.3%. There was benefit of intra-arterial treatment predicted for some individual patients from groups in which no treatment effect was found in previous subgroup analyses, such as those with no or poor collaterals.Conclusion The proposed clinical decision tool combines multiple baseline clinical and radiological characteristics and shows large variations in treatment benefit between patients. The tool is clinically useful as it aids in distinguishing between individual patients who may experience benefit from intra-arterial treatment for acute ischaemic stroke and those who will not.Trial registration clinicaltrials.gov NCT00359424 (IMS III) and isrctn.com ISRCTN10888758 (MR CLEAN).

Towards personalised intra-arterial treatment of patients with acute ischaemic stroke: a study protocol for development and validation of a clinical decision aid

INTRODUCTION

Overall, intra-arterial treatment (IAT) proved to be beneficial in patients with acute ischaemic stroke due to a proximal occlusion in the anterior circulation. However, heterogeneity in treatment benefit may be relevant for personalised clinical decision-making. Our aim is to improve selection of patients for IAT by predicting individual treatment benefit or harm.

METHODS AND ANALYSIS

We will use data collected in the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands (MR CLEAN) trial to analyse the effect of baseline characteristics on outcome and treatment effect. A multivariable proportional odds model with interaction terms will be developed to predict the outcome for each individual patient, both with and without IAT. Model performance will be expressed as discrimination and calibration, after bootstrap resampling and shrinkage of regression coefficients, to correct for optimism. External validation will be conducted on data of patients in the Interventional Management of Stroke III trial (IMS III). Primary outcome will be the modified Rankin Scale (mRS) at 90 days after stroke.

ETHICS AND DISSEMINATION

The proposed study will provide an internationally applicable clinical decision aid for IAT. Findings will be disseminated widely through peer-reviewed publications, conference presentations and in an online web application tool. Formal ethical approval was not required as primary data were already collected.

TRIAL REGISTRATION NUMBERS

ISRCTN10888758; Post-results and NCT00359424; Post-resultsc.

Mechanical thrombectomy in patients with M1 occlusion and NIHSS score ≤5: a single-centre experience

Background

The recent success of several mechanical thrombectomy trials has resulted in a significant change in management for patients presenting with stroke. However, it is still unclear how to manage patients that present with stroke and low National Institutes of Health Stroke Scale (NIHSS) ≤5. We sought to review our experience of mechanical thrombectomy in patients with low NIHSS and confirmed M1 occlusion.

Methods

We retrospectively analysed our prospectively maintained database of all patients undergoing mechanical thrombectomy between January 2008 and August 2016. We identified 41 patients with confirmed M1 occlusion and low NIHSS (≤5) on admission to our hospital. We collected demographic, radiological, procedural and outcome data.

Results

The mean age of patients was 72±14, with 20 male patients. Associated medical conditions were common with hypertension seen in ∼80%. Just over 50% presented with NIHSS 4 or 5. The average ASPECTS score on admission was 8.8 (range 6–10), and the average clot length 10 mm. Angiographically Thrombolysis in Cerebral Infarction (TICI) ≥2b was obtained in 87.8% of patients. 7 patients had haemorrhage on follow-up, 2 of which were symptomatic. Of 40 patients with 90-day follow-up, 75% had modified Rankin Scale (mRS) score 0–2. There were 3 deaths at 90 days.

Conclusions

Mechanical thrombectomy in patients with low NIHSS and proximal large vessel occlusion is technically possible and carries a high degree of success with good safety profile. Patients with low NIHSS and confirmed occlusion should be considered for mechanical thrombectomy.

Endovascular thrombectomy after large-vessel ischaemic stroke: a meta-analysis of individual patient data from five randomised trials

BACKGROUND

In 2015, five randomised trials showed efficacy of endovascular thrombectomy over standard medical care in patients with acute ischaemic stroke caused by occlusion of arteries of the proximal anterior circulation. In this meta-analysis we, the trial investigators, aimed to pool individual patient data from these trials to address remaining questions about whether the therapy is efficacious across the diverse populations included.

METHODS

We formed the HERMES collaboration to pool patient-level data from five trials (MR CLEAN, ESCAPE, REVASCAT, SWIFT PRIME, and EXTEND IA) done between December, 2010, and December, 2014. In these trials, patients with acute ischaemic stroke caused by occlusion of the proximal anterior artery circulation were randomly assigned to receive either endovascular thrombectomy within 12 h of symptom onset or standard care (control), with a primary outcome of reduced disability on the modified Rankin Scale (mRS) at 90 days. By direct access to the study databases, we extracted individual patient data that we used to assess the primary outcome of reduced disability on mRS at 90 days in the pooled population and examine heterogeneity of this treatment effect across prespecified subgroups. To account for between-trial variance we used mixed-effects modelling with random effects for parameters of interest. We then used mixed-effects ordinal logistic regression models to calculate common odds ratios (cOR) for the primary outcome in the whole population (shift analysis) and in subgroups after adjustment for age, sex, baseline stroke severity (National Institutes of Health Stroke Scale score), site of occlusion (internal carotid artery vs M1 segment of middle cerebral artery vs M2 segment of middle cerebral artery), intravenous alteplase (yes vs no), baseline Alberta Stroke Program Early CT score, and time from stroke onset to randomisation.

FINDINGS

We analysed individual data for 1287 patients (634 assigned to endovascular thrombectomy, 653 assigned to control). Endovascular thrombectomy led to significantly reduced disability at 90 days compared with control (adjusted cOR 2.49, 95% CI 1.76-3.53; p<0.0001). The number needed to treat with endovascular thrombectomy to reduce disability by at least one level on mRS for one patient was 2.6. Subgroup analysis of the primary endpoint showed no heterogeneity of treatment effect across prespecified subgroups for reduced disability (pinteraction=0.43). Effect sizes favouring endovascular thrombectomy over control were present in several strata of special interest, including in patients aged 80 years or older (cOR 3.68, 95% CI 1.95-6.92), those randomised more than 300 min after symptom onset (1.76, 1.05-2.97), and those not eligible for intravenous alteplase (2.43, 1.30-4.55). Mortality at 90 days and risk of parenchymal haematoma and symptomatic intracranial haemorrhage did not differ between populations.

INTERPRETATION

Endovascular thrombectomy is of benefit to most patients with acute ischaemic stroke caused by occlusion of the proximal anterior circulation, irrespective of patient characteristics or geographical location. These findings will have global implications on structuring systems of care to provide timely treatment to patients with acute ischaemic stroke due to large vessel occlusion.

FUNDING

Medtronic.

Mechanical thrombectomy in patients with acute ischemic stroke: a cost-utility analysis

BACKGROUND

The beneficial effects of endovascular treatment with new-generation mechanical thrombectomy devices compared with intravenous thrombolysis alone to treat acute large-artery ischemic stroke have been shown in randomized controlled trials (RCTs). This study aimed to estimate the cost utility of mechanical thrombectomy compared with the established standard of care.

METHODS

We developed a Markov decision process analytic model to assess the cost-effectiveness of treatment with mechanical thrombectomy plus intravenous thrombolysis versus treatment with intravenous thrombolysis alone from the public payer perspective in Canada. We conducted comprehensive literature searches to populate model inputs. We estimated the efficacy of mechanical thrombectomy plus intravenous thrombolysis from a meta-analysis of 5 RCTs, and we used data from the Oxford Vascular Study to model long-term clinical outcomes. We calculated incremental cost-effectiveness ratios (ICER) using a 5-year time horizon.

RESULTS

The base case analysis showed the cost and effectiveness of treatment with mechanical thrombectomy plus intravenous thrombolysis to be $126 939 and 1.484 quality-adjusted life-years (QALYs), respectively, and the cost and effectiveness of treatment with intravenous thrombolysis alone to be $124 419 and 1.273 QALYs, respectively. The mechanical thrombectomy plus intravenous thrombolysis strategy was associated with an ICER of $11 990 per QALY gained. Probabilistic sensitivity analysis showed that the probability of treatment with mechanical thrombectomy plus intravenous thrombolysis being cost-effective was 57.5%, 89.7% and 99.6% at thresholds of $20 000, $50 000 and $100 000 per QALY gained, respectively. The main factors influencing the ICER were time horizon, extra cost of mechanical thrombectomy treatment and age of the patient.

INTERPRETATION

Mechanical thrombectomy as an adjunct therapy to intravenous thrombolysis is cost-effective compared with treatment with intravenous thrombolysis alone for patients with acute large-artery ischemic stroke.

Safety and Efficacy of Solitaire Stent Thrombectomy: Individual Patient Data Meta-Analysis of Randomized Trials

BACKGROUND AND PURPOSE

Recent positive randomized trials of endovascular therapy for ischemic stroke used predominantly stent retrievers. We pooled data to investigate the efficacy and safety of stent thrombectomy using the Solitaire device in anterior circulation ischemic stroke.

METHODS

Patient-level data were pooled from trials in which the Solitaire was the only or the predominant device used in a prespecified meta-analysis (SEER Collaboration): Solitaire FR With the Intention for Thrombectomy as Primary Endovascular Treatment (SWIFT PRIME), Endovascular Treatment for Small Core and Anterior Circulation Proximal Occlusion With Emphasis on Minimizing CT to Recanalization Times (ESCAPE), Extending the Time for Thrombolysis in Emergency Neurological Deficits-Intra-Arterial (EXTEND-IA), and Randomized Trial of Revascularization With Solitaire FR Device Versus Best Medical Therapy in the Treatment of Acute Stroke Due to Anterior Circulation Large Vessel Occlusion Presenting Within Eight Hours of Symptom Onset (REVASCAT). The primary outcome was ordinal analysis of modified Rankin Score at 90 days. The primary analysis included all patients in the 4 trials with 2 sensitivity analyses: (1) excluding patients in whom Solitaire was not the first device used and (2) including the 3 Solitaire-only trials (excluding ESCAPE). Secondary outcomes included functional independence (modified Rankin Score 0-2), symptomatic intracerebral hemorrhage, and mortality.

RESULTS

The primary analysis included 787 patients: 401 randomized to endovascular thrombectomy and 386 to standard care, and 82.6% received intravenous thrombolysis. The common odds ratio for modified Rankin Score improvement was 2.7 (2.0-3.5) with no heterogeneity in effect by age, sex, baseline stroke severity, extent of computed tomography changes, site of occlusion, or pretreatment with alteplase. The number needed to treat to reduce disability was 2.5 and for an extra patient to achieve independent outcome was 4.25 (3.29-5.99). Successful revascularization occurred in 77% treated with Solitaire device. The rate of symptomatic intracerebral hemorrhage and overall mortality did not differ between treatment groups.

CONCLUSIONS

Solitaire thrombectomy for large vessel ischemic stroke was safe and highly effective with substantially reduced disability. Benefits were consistent in all prespecified subgroups.