Randomized Trial of Intraarterial Infusion of Urokinase Within 6 Hours of Middle Cerebral Artery Stroke

Post-thrombectomy rehabilitation strategies and 90-day outcomes in acute ischemic stroke patients enrolled in randomized controlled trials: A systematic review and meta-analysis

BackgroundThe post-thrombectomy recovery phase has significant influence on long-term patient outcomes. Our study aims to explore the effect of post-thrombectomy rehabilitation strategies on modified Rankin Scale (mRS) at 90-day.MethodsA search of PubMed, Scopus, Web of Science, ClinicalTrials.gov, and the Cochrane Library from inception to April 2024. Randomized controlled trials (RCTs) were included and assessed for quality using the Cochrane risk of bias tool. The rehabilitation strategies were divided into three groups: as per institutional care, as per national guideline, or not specified. We performed meta-regression to identify the association between rehabilitation strategy used and 90-day outcome defined using mRS.Results23 RCTs were included with 6649 patients (mean age 67 and 26% of patients were men). Rehabilitation "as per institutional care" was the most common (52%, 95% confidence interval (CI):31%-72%), followed by "as per national guidelines" (17%, 95% CI:5%-39%). We found statistically significant variations in proportions of rehabilitation strategies (F(2,97) = 0.035, p = 0.01). A two-proportion z-test indicated a borderline significant difference between "as per institutional care" (52%) and "as per national guidelines" (17%) (χ2(1) = 3.52, p = 0.06). In meta-regression, rehabilitation strategies used in the RCT significantly influenced the proportion of patients enrolled in the RCT who achieved mRS 0-2 at 90 days post-thrombectomy (QM (df = 1) = 5.06, p = 0.025). Trials using rehabilitation "as per institutional care" (log odds ratio (OR) = 0.64, 95% CI [0.42, 0.87], p < 0.01) and those using rehabilitation "as per national guidelines" (log odds ratio = 0.58, 95% CI [0.07-1.08], p = 0.02) were associated with statistical significantly higher odds of having higher proportion of patients with mRS 0-2 at 90 days.ConclusionsThere is variation in rehabilitation strategies utilized post-thrombectomy which influences functional outcomes at 90 days. Rehabilitation protocols should be standardized in RCTs evaluating thrombectomy in acute ischemic stroke patients.

Comparative effectiveness of intra-arterial thrombolysis vs. mechanical thrombectomy: a literature review

Background

Acute ischemic stroke (AIS) remains one of the leading causes of morbidity and mortality worldwide. Time is the single most critical factor in the management of patients presenting with AIS, where re-opening of occluded blood vessels is paramount. Intra-arterial thrombolysis (IAT) and mechanical thrombectomy (MT) are two such therapies employed to reestablish cerebrovascular blood flow in patients with AIS. This review compares both IAT and MT according to their efficacy, safety profiles, recanalization rates, clinical outcomes, and adverse procedural events.

Methods

Study abstraction from electronic search databases comprising PubMed/MEDLINE, ResearchGate, and the National Library of Medicine was used. Screening and selection of relevant articles were comprehensively conducted for this review. Direct comparisons between IAT and MT in terms of variables including recanalization rates, clinical outcomes, and adverse procedural events were warranted for study inclusion. Research determined to exhibit insufficient data or without comparable groups were subsequently excluded.

Results

MT was prompter when executing procedures than IAT, achieving greater rates of recanalization. Both interventions displayed similar results regarding rates of symptomatic intracranial hemorrhage (sICH) and mortality. Despite current available data indicating MT to demonstrate more efficiency as a procedure, further research is needed to examine IAT in light of specific patient demographics, clinical presentation, and circumstances.

Conclusion

This review elucidated that MT often takes less time peri-procedurally, achieving greater success in revascularization compared with that of IAT. Regarding mortality and sICH rates, IAT and MT comparison showed equivocal results. Thus, while making therapeutic decisions, it is important to consider the unique clinical features of each patient as well as the timing of interventions in order to maximize treatment outcomes.

Thrombolysis for acute ischaemic stroke: development and update

Thrombolytic therapy is a cornerstone in managing acute ischaemic stroke, marking significant advancements in treatment. Various generations of thrombolytics play crucial roles in different strategies, including intravenous thrombolysis, bridging therapy and thrombolysis beyond the conventional time window. The continuous development of thrombolytics has brought notable improvements. Compared to first-generation urokinase, second-generation alteplase and third-generation tenecteplase offer significant pharmacological advantages, such as enhanced fibrin specificity and longer half-lives. Tenecteplase demonstrates non-inferiority to alteplase regarding efficacy and safety, with the added benefit of a more convenient administration method. Ongoing trials continue to reveal additional evidence. Furthermore, other thrombolytic agents, including reteplase and non-immunogenic recombinant staphylokinase, are gaining increasing interest in the medical community. This review examines the structural characteristics, pharmacological properties, efficacy and safety profiles of these thrombolytic drugs. It also provides a detailed analysis of the performance of thrombolytic therapy in different acute ischaemic stroke patient subgroups, aiming to trace the evolution of these treatments and compare their effectiveness in acute ischaemic stroke. The goal is to offer a scientific basis for clinical practices and future development of thrombolytic therapies.

Ultrasound Evaluation for Shortening the Door-to-Puncture Time During Endovascular Treatment of Intracranial Vessel Occlusion

OBJECTIVE

Concerning endovascular treatment for acute ischemic stroke with intracranial vessel occlusion, shortening the door-to-puncture time (DTP) improves the patient's outcome. To determine endovascular treatment, magnetic resonance angiography or computed tomography angiography is performed for occluded vessel detection. Another detection method of internal carotid artery (ICA) occlusion or middle cerebral artery first segment (M1) occlusion is ultrasound (US). Bilateral flow pattern analysis of common carotid arteries by US leads to the diagnosis of ICA or M1 occlusion within a few minutes. Moreover, it can be conducted in the emergency department. The addition of the US for the initial evaluation of vessel occlusion can shorten the DTP. In this study, we evaluated the effectiveness of carotid artery US imaging in detecting large vessel occlusion (LVO) and shortening the DTP.

MATERIALS AND METHODS

This is a retrospective case-control study. Our analysis was based on the data from 150 patients with LVO or medium vessel occlusion who underwent endovascular revascularization treatment at our hospital between January 2015 and December 2022. Among them, 104 patients who had an anterior circulation vessel occlusion were included. They were divided into the US evaluation group and the non-US evaluation group, and their characteristics, treatment time course, and outcomes were compared.

RESULTS

This study included 104 patients with a median age of 81 years (interquartile range: 73-89 years), 57.7% were females, and the pre-stroke modified Rankin Scale (mRS) median was 0.5 (interquartile range: 0-3). Our cohort included advanced aged patients; therefore, this study included 56.7% of patients over 80 years old and 35.6% of pre-stroke mRS over 3. The US (US group) and non-US (non-US group) evaluation groups included 54 and 50 patients, respectively. As magnetic resonance imaging evaluation in the non-US group was performed over the 4.5 hours delayed arrival of patients from the last known well (LKW) to consider the evaluation of tPA administration, selection bias occurred. The US group included high National Institutes of Health Stroke Scale (NIHSS) patients (P = 0.0152) and more ICA occlusions (P = 0.0146). Onset (LKW) to door time was shorter in the US group (median, 75 min (35-146.5 minutes)) than the non-US group (median, 179 minutes (47.3-432.8 minutes); P = 0.0426), and the DTP was shorter for the US group (median, 75.5 minutes (63.8-87.3 minutes)) than for the non-US group (median, 85 minutes (67-129 minutes); P = 0.0102). Statistical difference was not seen in puncture to reperfusion time among the US group (median, 71.5 minutes (51-114 minutes)) and non-US group (median, 67 minutes (42.3-98.5 minutes); P = 0.5581). The onset (LKW) to reperfusion was shorter for the US group (median, 251 minutes (201-327.3 minutes)) than for the non-US group (median, 319 minutes (200-633.5 minutes); P = 0.0348). No statistical differences were seen for thrombolysis in cerebral infarction grade 2b-3 after treatment, improvement of NIHSS, and mRS at 90 days.

CONCLUSION

US is a useful imaging method to identify an anterior circulation LVO. It can distinguish patients with severe internal carotid or middle cerebral artery occlusion from medium vessel occlusion or other peripheral vessel occlusions. US helps to shorten the DTP time of LVO.

Blood pressure management in reperfused ischemic stroke

OBJECTIVES

This is a protocol for a Cochrane Review (intervention). The objectives are as follows: To assess the benefits and harms of intensive systolic blood pressure management (target less than 160 mmHg) versus conventional management (target less than 180 mmHg) in people undergoing ischemic stroke reperfusion via systemic thrombolysis or endovascular thrombectomy.

Intraarterial Thrombolysis as an Adjunct to Thrombectomy in Acute Ischemic Stroke: Current Status and Future Prospects

BACKGROUND AND PURPOSE

Intraarterial thrombolysis (IAT) has been sporadically used as an adjunct to mechanical thrombectomy (MT) in acute ischemic stroke patients for nearly two decades to improve distal arterial and microvascular perfusion even in patients with near complete or complete recanalization.

METHODS

We provide an overall narrative review that includes a systematic review and meta-analysis of two randomized controlled trials (RCTs), Chemical Optimization of Cerebral Embolectomy and Endovascular Recanalization in Patients with Acute Posterior Circulation Arterial Occlusion, to identify current and future implications. Risk ratios (RRs) were calculated from RCTs using a fixed-effects model. We identified 10 ongoing or planned RCTs after a search on clinicaltrials.gov and other sources, of which eight are in China, one in Europe, and one in Australia.

RESULTS

A previous meta-analysis of 16 (predominantly observational) studies involving 7572 MT-treated patients had identified 14% higher odds of functional independence (modified Rankin scale [mRS] 0-2) at 90 days in patients treated with IAT. In the current analysis of 321 patients who underwent MT in RCTs, 165 were randomized to IAT and 156 were in the control group. The RR of achieving an mRS score of 0-1 at 90 days postrandomization was higher in patients treated with IAT compared with the control group (absolute increase of 12.87%, RR = 1.39, 95% confidence interval [CI] 1.04-1.86). The rate of symptomatic intracerebral hemorrhage (sICH) within 24 h was slightly higher (absolute increase of 1.64%, RR = 0.95, 95% CI 0.07-13.30) in patients treated with IAT. The ongoing RCTs have sample sizes ranging from 80 to 498 that can identify very large minimal clinically important differences (MCIDs) (13%-20% increase) in primary outcomes, but smaller MCIDs (<10%) that can still result in practice changes with interventions associated with low cost and complexity and are easy to implement, such as IAT, will not be identified.

CONCLUSIONS

Observational studies and recent RCTs suggest a potential benefit of IAT in improving functional outcomes among patients post-MT, although the potentially increased risk of sICH, inadequate sample sizes, and lack of data from the United States need to be considered. A large, definitive, and generalizable RCT is required to establish the therapeutic value and safety profile of IAT prior to widespread incorporation into routine practice.

Intra-Arterial Urokinase After Endovascular Reperfusion for Acute Ischemic Stroke: The POST-UK Randomized Clinical Trial

Importance

Persisting or new thrombi in the distal arteries and the microcirculation have been reported to limit the benefits of successful endovascular thrombectomy for patients with acute ischemic stroke. It remains uncertain whether intra-arterial thrombolysis by urokinase following near-complete to complete reperfusion by thrombectomy improves outcomes among patients with ischemic stroke due to large vessel occlusion.

Objective

To assess the efficacy and adverse events of intra-arterial urokinase after near-complete to complete reperfusion by thrombectomy for acute ischemic stroke due to large vessel occlusion.

Design, Setting, and Participants

This investigator-initiated, randomized, open-label, blinded-end point trial was implemented at 35 hospitals in China, enrolling 535 patients with proximal intracranial large vessel occlusion presenting within 24 hours of time last known well, who achieved near-complete or complete reperfusion by endovascular thrombectomy and did not receive intravenous thrombolysis prior to the procedure. Recruitment took place between November 15, 2022, and March 29, 2024, with final follow-up on July 4, 2024.

Interventions

Eligible patients were randomly assigned to the intra-arterial urokinase group (a single dose of intra-arterial 100 000 IU urokinase injected in the initial target territory; n = 267) or control group (without intra-arterial thrombolysis; n = 267).

Main Outcomes and Measures

The primary efficacy outcome was the percentage of patients achieving survival without disability (modified Rankin Scale score of 0 or 1) at 90 days. The primary safety outcomes were mortality at 90 days and incidence of symptomatic intracranial hemorrhage within 48 hours.

Results

A total of 535 patients were enrolled (median age, 69 years; 223 [41.8%] female) and 532 (99.6%) completed the trial. The percentage of patients with survival without disability at 90 days was 45.1% (120/266) in the intra-arterial urokinase group and 40.2% (107/266) in the control group (adjusted risk ratio, 1.13 [95% CI, 0.94-1.36]; P = .19). Mortality at 90 days (18.4% vs 17.3%, respectively; adjusted hazard ratio, 1.06 [95% CI, 0.71-1.59]; P = .77) and incidence of symptomatic intracranial hemorrhage (4.1% vs 4.1%, respectively; adjusted risk ratio, 1.05 [95% CI, 0.45-2.44]; P = .91) were not significantly different between groups.

Conclusions and Relevance

Among patients with acute ischemic stroke due to large vessel occlusion, adjunct intra-arterial urokinase after near-complete to complete reperfusion by endovascular thrombectomy did not significantly increase the likelihood of survival without disability at 90 days.

Trial Registration

ChiCTR.org.cn Identifier: ChiCTR2200065617.

Bridging thrombolysis before endovascular therapy is associated with better outcomes in patients with large infarction core

BACKGROUND

This study investigates the efficacy and safety of bridging intravenous thrombolysis (IVT) before endovascular therapy (EVT) compared with EVT alone in patients with large infarction core.

METHODS

We conducted a comprehensive search of PubMed, EMBASE, and the Cochrane Library from January 2015 to June 2024. Included studies involved patients with acute ischemic stroke with an Alberta Stroke Program Early CT Score of ≤5 or an ischemic core volume of ≥50 mL. Studies were required to provide either 90-day modified Rankin Scale (mRS) score, reperfusion, symptomatic intracranial hemorrhage (sICH), or 90-day mortality.

RESULTS

Nine observational studies with 2641 patients were analyzed. The IVT+EVT group had a higher rate of 90-day functional independence (mRS 0-2; OR 1.56, 95% CI 1.31 to 1.87; adjusted OR (aOR) 1.43, 95% CI 1.21 to 1.68) and 90-day functional outcome (mRS 0-3; OR 1.34, 95% CI 1.11 to 1.62; aOR 1.18, 95% CI 1.02 to 1.37) compared with EVT alone. There was no significant difference in successful reperfusion (OR 1.01, 95% CI 0.62 to 1.64; aOR 1.07, 95% CI 0.74 to 1.54) and 90-day mortality (OR 0.86, 95% CI 0.73 to 1.02; aOR 0.89, 95% CI 0.77 to 1.04) between the two groups. Moreover, patients who received IVT+EVT had a higher rate of sICH (OR 1.30, 95% CI 1.03 to 1.64; aOR 2.21, 95% CI 1.22 to 4.01).

CONCLUSIONS

In patients with large infarction core, bridging IVT before EVT is associated with favorable functional outcomes compared with EVT, even though bridging therapy entails a higher risk of sICH. Further trials are needed to confirm these findings.

Concomitant Myocardial Infarction and Stroke Managed With a Unique Approach: A Case Report and Review of Literature

A 71-year-old gentleman presented with concomitant acute myocardial-cerebral infarction (AMCI). The patient was treated with a novel endovascular approach of simultaneous intracoronary (IC) and cerebral intra-arterial (IA) thrombolysis. The concomitant occurrence of acute myocardial infarction (AMI) and acute ischemic stroke (AIS) is a rare and challenging clinical scenario with a lack of established definitions and treatment guidelines. The preferred treatment approach of combined mechanical thrombectomy (MT) and percutaneous coronary intervention (PCI) is not widely available, hence necessitating the need to explore further practical and feasible treatment options.

Fibrinolytic Agents in Thromboembolic Diseases: Historical Perspectives and Approved Indications

Fibrinolytic agents catalyze the conversion of the inactive proenzyme plasminogen into the active protease plasmin, degrading fibrin within the thrombus and recanalizing occluded vessels. The history of these medications dates to the discovery of the first fibrinolytic compound, streptokinase, from bacterial cultures in 1933. Over time, researchers identified two other plasminogen activators in human samples, namely urokinase and tissue plasminogen activator (tPA). Subsequently, tPA was cloned using recombinant DNA methods to produce alteplase. Several additional derivatives of tPA, such as tenecteplase and reteplase, were developed to extend the plasma half-life of tPA. Over the past decades, fibrinolytic medications have been widely used to manage patients with venous and arterial thromboembolic events. Currently, alteplase is approved by the U.S. Food and Drug Administration (FDA) for use in patients with pulmonary embolism with hemodynamic compromise, ST-segment elevation myocardial infarction (STEMI), acute ischemic stroke, and central venous access device occlusion. Reteplase and tenecteplase have also received FDA approval for treating patients with STEMI. This review provides an overview of the historical background related to fibrinolytic agents and briefly summarizes their approved indications across various thromboembolic diseases.

Mechanistic correlation of molecular pathways in obesity-mediated stroke pathogenesis

Obesity, a prominent risk factor for the development of heart attacks and several cardiovascular ailments. Obesity ranks as the second most significant avoidable contributor to mortality, whereas stroke stands as the second leading cause of death on a global scale. While changes in lifestyle have been demonstrated to have significant impacts on weight management, the long-term weight loss remains challenging, and the global prevalence of obesity continues to rise. The pathophysiology of obesity has been extensively studied during the last few decades, and an increasing number of signal transduction pathways have been linked to obesity preclinically. This review is focused on signaling pathways, and their respective functions in regulating the consumption of fatty food as well as accumulation of adipose tissue, and the resulting morphological and cognitive changes in the brain of individuals with obesity. We have also emphasized the recent progress in the mechanisms behind the emergence of obesity, as elucidated by both experimental and clinical investigations. The mounting understanding of signaling transduction may shed light on the future course of obesity research as we move into a new era of precision medicine.

Intra-Arterial Thrombolysis is Associated with Delayed Reperfusion of Remaining Vessel Occlusions following Incomplete Thrombectomy

BACKGROUND AND PURPOSE

Intra-arterial thrombolytics may be used to treat distal vessel occlusions, which cause incomplete reperfusion following mechanical thrombectomy. Because immediate reperfusion after intra-arterial thrombolytics occurs rarely, the aim of this study was to assess the delayed effect of intra-arterial thrombolytics using follow-up perfusion imaging.

MATERIALS AND METHODS

We included patients from a prospective stroke registry (February 2015 to September 2022) who had undergone mechanical thrombectomy and had incomplete reperfusion (expanded TICI 2a-2c) and available 24 hour perfusion imaging. Perfusion imaging was rated as delayed reperfusion if time-sensitive perfusion maps did not show wedge-shaped delays suggestive of persisting occlusions corresponding to the post-mechanical thrombectomy angiographic deficit. Patients treated with intra-arterial thrombolytics were compared with controls using multivariable logistic regression and inverse probability of treatment weighting matching for baseline differences and factors associated with delayed reperfusion.

RESULTS

The median age of the final study population (n = 459) was 74 years (interquartile range, 63-81 years), and delayed reperfusion occurred in 61% of cases. Patients treated with additional intra-arterial thrombolytics (n = 40) were younger and had worse expanded TICI scores. After matching was performed, intra-arterial thrombolytics was associated with higher rates of delayed reperfusion (adjusted OR = 2.7; 95% CI, 1.1-6.4) and lower rates of new infarction in the residually hypoperfused territory after mechanical thrombectomy (adjusted OR = 0.3; 95% CI, 0.1-0.7). No difference was found in the rates of functional independence (90-day mRS, 0-2; adjusted OR = 1.4; 95% CI, 0.4-4.1).

CONCLUSIONS

Rescue intra-arterial thrombolytics is associated with delayed reperfusion of remaining vessel occlusions following incomplete mechanical thrombectomy. The value of intra-arterial thrombolytics as a potential therapy for incomplete reperfusions after mechanical thrombectomy should be assessed in the setting of randomized controlled trials.

Effect of intra-arterial thrombolysis following successful endovascular thrombectomy on functional outcomes in patients with large vessel occlusion acute ischemic stroke: A post-CHOICE meta-analysis

INTRODUCTION

Endovascular thrombectomy (EVT) is the standard treatment of acute ischemic stroke (AIS) due to large vessel occlusion (LVO). Although > 70% of patients in the trials assessing EVT for AIS-LVO had successful recanalization, only a third ultimately achieved favorable outcomes. A "no-reflow" phenomenon due to distal microcirculation disruption might contribute to such suboptimal outcomes. Combining intra-arterial (IA) tissue plasminogen activator (tPA) and EVT to reduce the distal microthrombi burden was investigated in a few studies. We present a pooled-data meta-analysis of the existing evidence of this combinatorial treatment.

METHODS

We followed the Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA) recommendations. We aimed to include all original studies investigating EVT plus IA tPA in AIS-LVO patients. Using R software, we calculated pooled odds ratios (ORs) with corresponding 95% confidence intervals (CI). A fixed-effects model was adopted to evaluate pooled data.

RESULTS

Five studies satisfied the inclusion criteria. Successful recanalization was comparable between the IA tPA and control groups at 82.9% and 82.32% respectively. The 90-day functional independence was similar between both groups (OR= 1.25; 95% CI= 0.92-1.70; P= 0.154). Symptomatic intracranial hemorrhage (sICH) was also comparable between both groups (OR= 0.66; 95% CI= 0.34-1.26; P= 0.304).

CONCLUSION

Our current meta-analysis does not show significant differences between EVT alone and EVT plus IA tPA in terms of functional independence or sICH. However, with the limited number of studies and included patients, more randomized controlled trials (RCTs) are needed to further investigate the benefits and safety of combined EVT and IA tPA.

Acute recanalization treatments in postnatal paediatric ischaemic arterial stroke. Paediatric stroke code

In children, arterial ischemic stroke is a much less understood disease compared to in adults due to its lower frequency and different aetiology. However, it is also a serious disease, with a high incidence of severe and permanent sequelae that exceeds 50% of total cases. The acute management of postnatal arterial ischaemic stroke (MNAIS) has changed drastically in recent years, chiefly on account of recanalization treatments (thrombolysis and endovascular therapies). These treatments, which used to not be recommended in childhood, are increasingly implemented in everyday clinical practice. Although the evidence from studies carried out in children is not of high quality due to their retrospective design and the small number of reported cases, they support the hypothesis that these treatments are as safe and effective as they are in adults as long as appropriate eligibility criteria are applied and they are used within a certain time from the onset of symptoms (therapeutic window). This article reviews the acute management of postnatal paediatric arterial ischemic stroke based on the current scientific evidence. Since the efficacy of these treatments is highly dependent on their early initiation, a paediatric stroke code needs to be in place as an extension of the stroke code applied to adults. It has started to be introduced in Spain since 2019, although there are still large areas of the country where it has yet to be applied.

Intraarterial urokinase for thrombus migration after mechanical thrombectomy for large vessel ischemic stroke

BACKGROUND

Achieving rapid and complete reperfusion is the ultimate purpose for ischemic stroke with large vessel occlusion (LVO). Although mechanical thrombectomy (MT) had been a proverbially important procedure, medium vessel occlusion (MeVO) with thrombus migration can sporadically occur after MT. Moreover, the safe and effective approach for such had been unknown. We reported thrombolysis with intraarterial urokinase for MeVO with thrombus migration after MT.

METHODS

We included 122 patients who were treated by MT with LVO stroke at our institution between April 2019 and March 2021. Of 26 patients (21.3%) who developed MeVO with thrombus migration after MT, 11 (9.0%) underwent additional MT (MT group) and 15 (12.3%) received intraarterial urokinase (UK group). The procedure time; angiographically modified Treatment in Cerebral Ischemia Scale (mTICI); functional independence, which was defined as modified Rankin Scale 0-2, on day 30 or upon discharge; and symptomatic and asymptomatic intracerebral hemorrhage (ICH) were compared between the UK and MT groups.

RESULTS

The procedure time, mTICI, and asymptomatic ICH did not significantly differ between the groups. In the UK group, 8 of 15 (53.3%) patients obtained functional independence, and the functional independence rate was significantly higher in the UK group than in the MT group (p < 0.05). Symptomatic ICH did not occur in the UK group, and its incidence was significantly smaller than that in the MT group (p < 0.05).

CONCLUSION

The results of this study suggest that intraarterial urokinase for MeVO with thrombus migration after MT may safely improve angiographic reperfusion.

Intra-arterial thrombolytics during endovascular thrombectomy for acute ischaemic stroke in the MR CLEAN Registry

INTRODUCTION

The efficacy and safety of local intra-arterial (IA) thrombolytics during endovascular thrombectomy (EVT) for large-vessel occlusions is uncertain. We analysed how often IA thrombolytics were administered in the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands (MR CLEAN) Registry, whether it was associated with improved functional outcome and assessed technical and safety outcomes compared with EVT without IA thrombolytics.

METHODS

In this observational study, we included patients undergoing EVT for an acute ischaemic stroke in the anterior circulation from the MR CLEAN Registry (March 2014-November 2017). The primary endpoint was favourable functional outcome, defined as an modified Rankin Scale score ≤2 at 90 days. Secondary endpoints were reperfusion status, early neurological recovery and symptomatic intracranial haemorrhage (sICH). Subgroup analyses for IA thrombolytics as primary versus adjuvant revascularisation attempt were performed.

RESULTS

Of the 2263 included patients, 95 (4.2%) received IA thrombolytics during EVT. The IA thrombolytics administered were urokinase (median dose, 250 000 IU (IQR, 1 93 750-2 50 000)) or alteplase (median dose, 20 mg (IQR, 12-20)). No association was found between IA thrombolytics and favourable functional outcome (adjusted OR (aOR), 1.16; 95% CI 0.71 to 1.90). Successful reperfusion was less often observed in those patients treated with IA thrombolytics (aOR, 0.57; 95% CI 0.36 to 0.90). The odds of sICH (aOR, 0.82; 95% CI 0.32 to 2.10) and early neurological recovery were comparable between patients treated with and without IA thrombolytics. For primary and adjuvant revascularisation attempts, IA thrombolytics were more often administered for proximal than for distal occlusions. Functional outcomes were comparable for patients receiving IA thrombolytics as a primary versus adjuvant revascularisation attempt.

CONCLUSION

Local IA thrombolytics were rarely used in the MR CLEAN Registry. In the relatively small study sample, no statistical difference was observed between groups in the rate of favourable functional outcome or sICH. Patients whom required and underwent IA thrombolytics were patients less likely to achieve successful reperfusion, probably due to selection bias.

Motor sequela of adult and pediatric stroke: Imminent losses and ultimate gains

Stroke is the leading cause of neurological disability in the United States and worldwide. Remarkable advances have been made over the past 20 years in acute vascular treatments to reduce infarct size and improve neurological outcome. Substantially less progress has been made in the understanding and clinical approaches to neurological recovery after stroke. This chapter reviews the epidemiology, bedside examination, localization approaches, and classification of stroke, with an emphasis on motor stroke presentations and management, and promising research approaches to enhancing motor aspects of stroke recovery.

Safety and efficacy of low-cost alternative urokinase in acute ischemic stroke: A systematic review and meta-analysis

INTRODUCTION

Use of intravenous thrombolysis (IVT) for treatment of acute ischemic stroke (AIS) varies greatly between countries, ranging from 10% to 15% in high-income countries to less than 2% in low- and middle income countries (LMICs). This is because alteplase is expensive and has been cited as one of the most common barriers to IVT in LMICs. Urokinase (UK) is a thrombolytic agent which is almost 50 times cheaper with easier production and purification than alteplase. UK may become a cost-effective option for IVT in LMICs if it is found to be safe and effective. We conducted this study to assess the existing evidence on the safety and efficacy of UK vs alteplase for IVT in AIS.

METHODS

The study was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and meta-Analyses) guideline. Systematic literature search was done in PubMed, EMBASE, and Google Scholar for English literature published from 2010 to 2021.

RESULTS

A total of 4061 participants in the alteplase and 2062 participants in the UK group were included in the final statistical analysis. After IVT, a good functional outcome at last follow-up was found among 80.57 % of patients in the alteplase group compared to 73.79 % of patients in the UK group (OR: 1.11; 95 % CI: 0.95- 1.31; I2 = 0 %; P = 0.18). Symptomatic Intracerebral Hemorrhage (sICH) was found among 1.77 % of patients in the alteplase group compared to 2.83 % of patients in the UK group (OR: 0.84; 95 % CI: 0.56- 1.26; I2 = 0 %; P = 0.41). Similarly, mortality was found among 5.03 % of patients in the alteplase group compared to 5.42 % of patients in the UK group (OR: 0.87; 95 % CI: 0.66-1.14; I2 = 0 %; P = 0.30).

CONCLUSION

Our meta-analysis found that intravenous UK is not inferior to alteplase in terms of safety and efficacy and can be a viable alternative for IVT in AIS patients in LMICs.

Intra-Arterial Thrombolysis Vs. Mechanical Thrombectomy in Acute Minor Ischemic Stroke Due to Large Vessel Occlusion

Background

The efficacy and safety of mechanical thrombectomy (MT) in acute large vessel occlusion (LVO) patients with minor stroke (NIHSS ≤ 5) remains undetermined. We aimed to compare the efficacy and safety of intra-arterial thrombolysis (IAT) alone vs. MT for LVO patients with minor stroke.

Methods

Patients were selected from the Acute Ischemic Stroke Cooperation Group of Endovascular Treatment (ANGEL) registry, a prospective multicenter registry study, and divided into MT and IAT alone groups. We compared the outcome measures between the two groups, including 90-day functional outcome evaluated by the modified Rankin Scale (mRS), the final recanalization level, intracranial hemorrhage, and mortality within 90-days by logistic regression models with adjustment. Besides the conventional multivariable analysis, we performed a sensitivity analysis by adjusting the propensity score to confirm our results. The propensity score was derived using a logistic regression model.

Results

Of the 120 patients, 63 received IAT alone and 57 received MT as the first-line treatment strategy. As compared to MT group, patients in the IAT alone group were associated with a higher chance of 90-day mRS 0-2 [93.7% vs. 71.9%, odds ratio (OR) = 4.75, 95% confidence interval (CI): 1.20–18.80, P = 0.027], a high chance of 90-day mRS 0-3 (96.8% vs. 86.7%, OR = 11.35, 95% CI: 1.93–66.86, P = 0.007), a shorter median time from puncture to recanalization (PTR) (60 min vs. 100 min, β = −63.70, 95% CI: −81.79– −45.61, P < 0.001), a lower chance of any intracranial hemorrhage (ICH) within 48 h (3.2% vs. 19.3%, OR = 0.15, 95% CI: 0.03–0.79, P = 0.025), and a lower chance of mortablity within 90 days (1.6% vs. 9.2%, OR = 0.05, 95% CI: 0.01–0.57, P = 0.016). Similarly, the sensitivity analysis showed the robustness of the primary analysis.

Conclusions

Compared with MT, IAT may improve 90-day clinical outcomes with decreased ICH rate and mortality in LVO patients with minor stroke.

Intravenous thrombolysis and endovascular thrombectomy for acute ischaemic stroke in patients with Moyamoya disease - a systematic review and meta-summary of case reports

BACKGROUND AND AIMS

Patients with Moyamoya disease (MMD) can present with ischaemic or haemorrhagic stroke. There is no good evidence for treatment strategies in MMD-associated acute ischaemic stroke (AIS), particularly for treatments like intravenous thrombolysis (IVT) and endovascular thrombectomy (ET). As the intracranial vessels are friable in MMD, and the risk of bleeding is high, the use of IVT and ET is controversial. To clarify the safety and efficacy of IVT/ET in the treatment of MMD-associated AIS, we performed a systematic review and meta-summary to examine this issue.

METHODS

A systematic search was performed from four electronic databases: PubMed (MEDLINE), Cochrane Library, EMBASE and Scopus, profiling data from inception till 21 November 2021, as well as, manually on Google Scholar.

RESULTS

Ten case reports detailing 10 MMD patients presenting with AIS and undergoing IVT or ET, or both, were included in the analysis. The median National Institute of Health Stroke Scale score at presentation was 10 (Interquartile Range [IQR] = 6.0-16.5). IVT alone was instituted in 6 patients, primary ET was attempted in 2, and 2 had received bridging IVT with ET. Of the 4 patients who underwent ET, 2 patients achieved successful reperfusion (modified Thrombolysis In Cerebral Infarction scale [mTICI] ≥ 2b). In terms of functional outcomes, One patient achieved complete recovery (modified Rankin Scale 0), 4 patients attained improvement in neurological status, and 4 had no improvement, whilst functional outcome was unreported in 1 patient. No patient experienced symptomatic intracranial haemorrhage.

CONCLUSIONS

In this systematic review and meta-summary, the utility of IVT and ET in MMD-associated AIS appears feasible in selected cases. Further larger cohort studies are required to evaluate these treatment approaches.

HIGHLIGHTS

· AIS in MMD was typically managed with bypass surgery but not via thrombolysis or thrombectomy. · In this meta-summary, all patients treated with thrombolysis and/or thrombectomy survived and some experienced symptomatic and/or functional improvement. · Further larger cohort studies are necessary for investigating the role of thrombolysis and/or thrombectomy as treatment of AIS in MMD.

Patient and procedure selection for mechanical thrombectomy: Toward personalized medicine and the role of artificial intelligence

Mechanical thrombectomy (MT) for ischemic stroke due to large vessel occlusion is standard of care. Evidence-based guidelines on eligibility for MT have been outlined and evidence to extend the treatment benefit to more patients, particularly those at the extreme ends of a stroke clinical severity spectrum, is currently awaited. As patient selection continues to be explored, there is growing focus on procedure selection including the tools and techniques of thrombectomy and associated outcomes. Artificial intelligence (AI) has been instrumental in the area of patient selection for MT with a role in diagnosis and delivery of acute stroke care. Machine learning algorithms have been developed to detect cerebral ischemia and early infarct core, presence of large vessel occlusion, and perfusion deficit in acute ischemic stroke. Several available deep learning AI applications provide ready visualization and interpretation of cervical and cerebral arteries. Further enhancement of AI techniques to potentially include automated vessel probe tools in suspected large vessel occlusions is proposed. Value of AI may be extended to assist in procedure selection including both the tools and technique of thrombectomy. Delivering personalized medicine is the wave of the future and tailoring the MT treatment to a stroke patient is in line with this trend.

The End of Tissue-Type Plasminogen Activator's Reign?

Mechanical thrombectomy is a highly effective treatment for acute ischemic stroke caused by large-vessel occlusion in the anterior cerebral circulation, significantly increasing the likelihood of recovery to functional independence. Until recently, whether intravenous thrombolysis before mechanical thrombectomy provided additional benefits to patients with acute ischemic stroke-large-vessel occlusion remained unclear. Given that reperfusion is a key factor for clinical outcome in patients with acute ischemic stroke-large-vessel occlusion and the efficacy of both intravenous thrombolysis and mechanical thrombectomy is time-dependent, achieving complete reperfusion with a single pass should be the primary angiographic goal. However, it remains undetermined whether extending the procedure with additional endovascular attempts or local lytics administration safely leads to higher reperfusion grades and whether there are significant public health and cost implications. Here, we outline the current state of knowledge and research avenues that remain to be explored regarding the consistent therapeutic benefit of intravenous thrombolysis in anterior circulation strokes and the potential place of adjunctive intra-arterial lytics administration, including alternative thrombolytic agent place.

Indications for Mechanical Thrombectomy for Acute Ischemic Stroke: Current Guidelines and Beyond

PURPOSE OF THE REVIEW

This article reviews recent breakthroughs in the treatment of acute ischemic stroke, mainly focusing on the evolution of endovascular thrombectomy, its impact on guidelines, and the need for and implications of next-generation randomized controlled trials.

RECENT FINDINGS

Endovascular thrombectomy is a powerful tool to treat large vessel occlusion strokes and multiple trials over the past 5 years have established its safety and efficacy in the treatment of anterior circulation large vessel occlusion strokes up to 24 hours from stroke onset.

SUMMARY

In 2015, multiple landmark trials (MR CLEAN, ESCAPE, SWIFT PRIME, REVASCAT, and EXTEND IA) established the superiority of endovascular thrombectomy over medical management for the treatment of anterior circulation large vessel occlusion strokes. Endovascular thrombectomy has a strong treatment effect with a number needed to treat ranging from 3 to 10. These trials selected patients based on occlusion location (proximal anterior occlusion: internal carotid or middle cerebral artery), time from stroke onset (early window: up to 6-12 hours), and acceptable infarct burden (Alberta Stroke Program Early CT Score [ASPECTS] ≥6 or infarct volume <50 mL). In 2017, the DAWN and DEFUSE-3 trials successfully extended the time window up to 24 hours in appropriately selected patients. Societal and national thrombectomy guidelines have incorporated these findings and offer Class 1A recommendation to a subset of well-selected patients. Thrombectomy ineligible stroke subpopulations are being studied in ongoing randomized controlled trials. These trials, built on encouraging data from pooled analysis of early trials (HERMES collaboration) and emerging retrospective data, are studying large vessel occlusion strokes with mild deficits (National Institutes of Health Stroke Scale <6) and large infarct burden (core volume >70 mL).

Impact of dose reduction and iterative model reconstruction on multi-detector CT imaging of the brain in patients with suspected ischemic stroke

Non-contrast cerebral computed tomography (CT) is frequently performed as a first-line diagnostic approach in patients with suspected ischemic stroke. The purpose of this study was to evaluate the performance of hybrid and model-based iterative image reconstruction for standard-dose (SD) and low-dose (LD) non-contrast cerebral imaging by multi-detector CT (MDCT). We retrospectively analyzed 131 patients with suspected ischemic stroke (mean age: 74.2 ± 14.3 years, 67 females) who underwent initial MDCT with a SD protocol (300 mAs) as well as follow-up MDCT after a maximum of 10 days with a LD protocol (200 mAs). Ischemic demarcation was detected in 26 patients for initial and in 64 patients for follow-up imaging, with diffusion-weighted magnetic resonance imaging (MRI) confirming ischemia in all of those patients. The non-contrast cerebral MDCT images were reconstructed using hybrid (Philips “iDose4”) and model-based iterative (Philips “IMR3”) reconstruction algorithms. Two readers assessed overall image quality, anatomic detail, differentiation of gray matter (GM)/white matter (WM), and conspicuity of ischemic demarcation, if any. Quantitative assessment included signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) calculations for WM, GM, and demarcated areas. Ischemic demarcation was detected in all MDCT images of affected patients by both readers, irrespective of the reconstruction method used. For LD imaging, anatomic detail and GM/WM differentiation was significantly better when using the model-based iterative compared to the hybrid reconstruction method. Furthermore, CNR of GM/WM as well as the SNR of WM and GM of healthy brain tissue were significantly higher for LD images with model-based iterative reconstruction when compared to SD or LD images reconstructed with the hybrid algorithm. For patients with ischemic demarcation, there was a significant difference between images using hybrid versus model-based iterative reconstruction for CNR of ischemic/contralateral unaffected areas (mean ± standard deviation: SD_IMR: 4.4 ± 3.1, SD_iDose: 3.5 ± 2.3, P < 0.0001; LD_IMR: 4.6 ± 2.9, LD_iDose: 3.2 ± 2.1, P < 0.0001).  In conclusion, model-based iterative reconstruction provides higher CNR and SNR without significant loss of image quality for non-enhanced cerebral MDCT.

Predictors of hemorrhagic complications after intravenous thrombolysis in acute cerebral infarction patients: A single-center study of 391 cases

For patients with ischemic stroke, intravenous (IV) thrombolysis with Urokinase within 6 hours has been accepted as beneficial, but its application is limited by high risk of hemorrhagic complications after thrombolysis. This study aimed to analyze the risk factors of hemorrhagic complications after intravenous thrombolysis using Urokinase in acute cerebral infarction (ACI) patients.Total 391 consecutive ACI patients were enrolled and divided into 2 groups: the hemorrhagic complications group and the non-hemorrhagic complications group. The related data were collected and analyzed.Univariate analysis showed significant differences in prothrombin time, atrial fibrillation (AF), Mean platelet volume, large platelet ratio (L-PLR), triglyceride (TG), Lactate dehydrogenase, alanine aminotransferase (ALT), high-density lipoprotein, and baseline National Institute of Health Stroke Scale score between the hemorrhagic complications and the non-hemorrhagic complications group (P < .1). Multivariate logistic regression analysis indicated that AF (odds ratio [OR] = 2.91, 95% confidence interval [CI] = 1.06-7.99 P = .039) was the risk factor of hemorrhagic complications, while ALT (OR = 0.27, 95% CI = 0.10-0.72 P = .009) and TG (OR = 0.16, 95% CI = 0.06-0.45 P = .000) were protective factors of hemorrhagic complications.For patients with AF and lower levels of ALT or TG, the risk of hemorrhagic complications might increase after ACI.

Endovascular thrombectomy and intra-arterial interventions for acute ischaemic stroke

BACKGROUND

Most disabling strokes are due to a blockage of a large artery in the brain by a blood clot. Prompt removal of the clot with intra-arterial thrombolytic drugs or mechanical devices, or both, can restore blood flow before major brain damage has occurred, leading to improved recovery. However, these so-called endovascular interventions can cause bleeding in the brain. This is a review of randomised controlled trials of endovascular thrombectomy or intra-arterial thrombolysis, or both, for acute ischaemic stroke.

OBJECTIVES

To assess whether endovascular thrombectomy or intra-arterial interventions, or both, plus medical treatment are superior to medical treatment alone in people with acute ischaemic stroke.

SEARCH METHODS

We searched the Trials Registers of the Cochrane Stroke Group and Cochrane Vascular Group (last searched 1 September 2020), CENTRAL (the Cochrane Library, 1 September 2020), MEDLINE (May 2010 to 1 September 2020), and Embase (May 2010 to 1 September 2020). We also searched trials registers, screened reference lists, and contacted researchers.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of any endovascular intervention plus medical treatment compared with medical treatment alone in people with definite ischaemic stroke.

DATA COLLECTION AND ANALYSIS

Two review authors (MBR and MJ) applied the inclusion criteria, extracted data, and assessed trial quality. Two review authors (MBR and HL) assessed risk of bias, and the certainty of the evidence using GRADE. We obtained both published and unpublished data if available. Our primary outcome was favourable functional outcome at the end of the scheduled follow-up period, defined as a modified Rankin Scale score of 0 to 2. Eighteen trials (i.e. all but one included trial) reported their outcome at 90 days. Secondary outcomes were death from all causes at in the acute phase and by the end of follow-up, symptomatic intracranial haemorrhage in the acute phase and by the end of follow-up, neurological status at the end of follow-up, and degree of recanalisation.

MAIN RESULTS

We included 19 studies with a total of 3793 participants. The majority of participants had large artery occlusion in the anterior circulation, and were treated within six hours of symptom onset with endovascular thrombectomy. Treatment increased the chance of achieving a good functional outcome, defined as a modified Rankin Scale score of 0 to 2: risk ratio (RR) 1.50 (95% confidence interval (CI) 1.37 to 1.63; 3715 participants, 18 RCTs; high-certainty evidence). Treatment also reduced the risk of death at end of follow-up: RR 0.85 (95% CI 0.75 to 0.97; 3793 participants, 19 RCTs; high-certainty evidence) without increasing the risk of symptomatic intracranial haemorrhage in the acute phase: RR 1.46 (95% CI 0.91 to 2.36; 1559 participants, 6 RCTs; high-certainty evidence) or by end of follow-up: RR 1.05 (95% CI 0.72 to 1.52; 1752 participants, 10 RCTs; high-certainty evidence); however, the wide confidence intervals preclude any firm conclusion. Neurological recovery to National Institutes of Health Stroke Scale (NIHSS) score 0 to 1 and degree of recanalisation rates were better in the treatment group: RR 2.03 (95% CI 1.21 to 3.40; 334 participants, 3 RCTs; high-certainty evidence) and RR 3.11 (95% CI 2.18 to 4.42; 268 participants, 3 RCTs; high-certainty evidence), respectively.

AUTHORS' CONCLUSIONS

In individuals with acute ischaemic stroke due to large artery occlusion in the anterior circulation, endovascular thrombectomy can increase the chance of survival with a good functional outcome without increasing the risk of intracerebral haemorrhage or death.

Impact of Procedure Time on Clinical Outcomes of Patients Who Underwent Endovascular Therapy for Acute Ischemic Stroke

BACKGROUND AND PURPOSE

The time from onset to reperfusion is associated with clinical outcomes in acute ischemic stroke due to large vessel occlusion (LVO); nevertheless, the time limit of the continuing procedure remains unclear. We analyzed the relationship between procedure time and clinical outcomes in patients with LVO who underwent endovascular treatment (EVT).

METHODS

We assessed 1,247 patients who underwent EVT for LVO. Data were obtained from our multicenter registry, and patients were included if data on procedure time were available. Multivariate analysis was performed to assess the impact of procedure time on clinical outcomes using the following parameters: favorable outcome (the modified Rankin score of 0-2 at 90 days), mortality within 90 days, symptomatic intracranial hemorrhage within 72 h after stroke onset, and procedure-related complications.

RESULTS

The rate of favorable outcomes linearly decreased with increasing procedure time, but there was no linear relationship between procedure time and other outcomes. The adjusted odds ratio for 30-minute delay in procedure time was 0.76 (95% confidence interval, 0.68-0.84) for favorable outcome, 1.15 (0.97-1.36) for mortality, 1.08 (0.87-1.33) for symptomatic intracranial hemorrhage, and 0.92 (0.75-1.16) for complications. Significant interactions in the effect of procedure time on favorable outcome were observed between the subgroups stratified by age (≥75 or <75 years). Younger patients had a greater deleterious effect of delayed reperfusion.

CONCLUSIONS

Increasing procedure time was associated with less favorable outcomes, but not with the rate of mortality, symptomatic intracerebral hemorrhage, or complications in our cohort.

Effectiveness of intravenous r-tPA versus UK for acute ischaemic stroke: a nationwide prospective Chinese registry study

Background

Intravenous recombinant tissue plasminogen activator (r-tPA) and urokinase (UK) are both recommended for the treatment of acute ischaemic stroke (AIS) in China, but with few comparative outcome data being available. We aimed to compare the outcomes of these two thrombolytic agents for the treatment of patients within 4.5 hours of onset of AIS in routine clinical practice in China.

Methods

A pre-planned, prospective, nationwide, multicentre, real-world registry of consecutive patients with AIS (age ≥18 years) who received r-tPA or UK within 4.5 hours of symptom onset according to local decision-making and guideline recommendations during 2017–2019. The primary effectiveness outcome was the proportion of patients with an excellent functional outcome (defined by modified Rankin scale scores 0 to 1) at 90 days. The key safety endpoint was symptomatic intracranial haemorrhage according to standard definitions. Multivariable logistic regression was used for comparative analysis, with adjustment according to propensity scores to ensure balance in baseline characteristics.

Results

Overall, 4130 patients with AIS were registered but 320 had incomplete or missing data, leaving 3810 with available data for analysis of whom 2666 received r-tPA (median dose 0.88 (IQR 0.78–0.90) mg/kg) and 1144 received UK (1.71 (1.43–2.00)×10⁴ international unit per kilogram). There were several significant intergroup differences in patient characteristics: r-tPA patients were more educated, had less history of stroke, lower systolic blood pressure, greater neurological impairment and shorter treatment times from symptom onset than UK patients. However, in adjusted analysis, the frequency of excellent outcome (OR 1.18, 95% CI 1.00 to 1.40, p=0.052) and symptomatic intracranial haemorrhage (OR 0.70, 95% CI 0.33 to 1.47, p=0.344) were similar between groups.

Conclusions

UK may be as effective and carry a similar safety profile as r-tPA in treating mild to moderate AIS within guidelines in China.

Registration

http://www.clinicaltrials.gov. unique identifier: NCT02854592.

Intra-Arterial Thrombolysis after Unsuccessful Mechanical Thrombectomy in the STRATIS Registry

BACKGROUND AND PURPOSE

Recent data suggest that intra-arterial thrombolytics may be a safe rescue therapy for patients with acute ischemic stroke after unsuccessful mechanical thrombectomy; however, safety and efficacy remain unclear. Here, we evaluate the use of intra-arterial rtPA as a rescue therapy in the Systematic Evaluation of Patients Treated with Neurothrombectomy Devices for Acute Ischemic Stroke (STRATIS) registry.

MATERIALS AND METHODS

STRATIS was a prospective, multicenter, observational study of patients with acute ischemic stroke with large-vessel occlusions treated with the Solitaire stent retriever as the first-line therapy within 8 hours from symptom onset. Clinical and angiographic outcomes were compared in patients having rescue therapy treated with and without intra-arterial rtPA. Unsuccessful mechanical thrombectomy was defined as any use of rescue therapy.

RESULTS

A total of 212/984 (21.5%) patients received rescue therapy, of which 83 (39.2%) and 129 (60.8%) were in the no intra-arterial rtPA and intra-arterial rtPA groups, respectively. Most occlusions were M1, with 43.4% in the no intra-arterial rtPA group and 55.0% in the intra-arterial rtPA group (P = .12). The median intra-arterial rtPA dose was 4 mg (interquartile range = 2-12 mg). A trend toward higher rates of substantial reperfusion (modified TICI  ≥ 2b) (84.7% versus 73.0%, P = .08), good functional outcome (59.2% versus 46.6%, P = .10), and lower rates of mortality (13.3% versus 23.3%, P = .08) was seen in the intra-arterial rtPA cohort. Rates of symptomatic intracranial hemorrhage did not differ (0% versus 1.6%, P = .54).

CONCLUSIONS

Use of intra-arterial rtPA as a rescue therapy after unsuccessful mechanical thrombectomy was not associated with an increased risk of symptomatic intracranial hemorrhage or mortality. Randomized clinical trials are needed to understand the safety and efficacy of intra-arterial thrombolysis as a rescue therapy after mechanical thrombectomy.

Intracranial Bleeding After Reperfusion Therapy in Acute Ischemic Stroke

Intracranial hemorrhage is one of the most feared complications following brain infarct. Ischemic tissues have a natural tendency to bleed. Moreover, the first recanalization trials using intravenous thrombolysis have shown an increase in mild to severe intracranial hemorrhage. Symptomatic intracerebral hemorrhage is strongly associated with poor outcomes and is an important factor in recanalization decisions. Stroke physicians have to weigh the potential benefit of recanalization therapies, first, with different risks of intracranial hemorrhage described in randomized controlled trials, and second with numerous risk markers that have been found to be associated with intracranial hemorrhage in retrospective series. These decisions have become quite complex with different intravenous thrombolytics and mechanical thrombectomy. This review aims to outline some elements of the pathophysiological mechanisms and classifications, describe most of the risk factors identified for each reperfusion therapy, and finally suggest future research directions that could help physicians dealing with these complications.

Bleeding from an Unruptured Cerebral Aneurysm following the Local Intra-arterial Administration of Urokinase: A Case Report

A 57-year-old woman with a wide-necked anterior communicating artery (Acom) aneurysm underwent stent-assisted coiling (SAC) due to aneurysm enlargement. Dual antiplatelet therapy was initiated 7 days before the operation, and systemic heparinization was performed while maintaining an activated clotting time (ACT) of approximately 300 s during the procedure. SAC was performed using a laser-cut closed-cell stent and bare platinum coils. At the end of the procedure, the Acom and right anterior cerebral artery (ACA) were occluded by in-stent thrombosis. Following local intra-arterial administration of 480000 U of urokinase, the Acom and right ACA were recanalized, accompanied by extravasation around the Acom aneurysm. A computed tomography (CT) scan revealed a right frontal hematoma, which did not enlarge after the administration of protamine sulfate. The hematoma disappeared spontaneously, and the patient recovered without any neurological deficits. Local administration of urokinase is an effective treatment for in-stent thrombosis. However, because the devices for SAC may cause mechanical injuries to the aneurysms, urokinase should be used cautiously for cerebral aneurysms, even if unruptured.

Biomechanics and hemodynamics of stent-retrievers

In 2015, multiple randomized clinical trials showed an unparalleled treatment benefit of stent-retriever thrombectomy as compared to standard medical therapy for the treatment of a large artery occlusion causing acute ischemic stroke. A short time later, the HERMES collaborators presented the patient-level pooled analysis of five randomized clinical trials, establishing class 1, level of evidence A for stent-retriever thrombectomy, in combination with intravenous thrombolysis when indicated to treat ischemic stroke. In the years following, evidence continues to mount for expanded use of this therapy for a broader category of patients. The enabling technology that changed the tide to support endovascular treatment of acute ischemic stroke is the stent-retriever. This review summarizes the history of intra-arterial treatment of stroke, introduces the biomechanics of embolus extraction with stent-retrievers, describes technical aspects of the intervention, provides a description of hemodynamic implications of stent-retriever embolectomy, and proposes future directions for a more comprehensive, multi-modal endovascular approach for the treatment of acute ischemic stroke.

[To guide and train young neurologists as stroke specialists: proceedings of the third annual workshop for stroke education]

The Japanese Society of Neurology has held an annual workshop for stroke education since September 2018 for young members of the society and medical students to take an interest in stroke medicine and stroke research and to contribute to conquest of stroke, a national disease. The third annual workshop will be held in the National Cerebral and Cardiovascular Center, Osaka in September 2020 also with the support of the Japan Stroke Society. Designated lecturers are preparing for presentation of their own devising. Here, brief abstracts of educational lectures and special statements on career formation of vascular neurologists are introduced.

Pathophysiology and Treatment of Stroke: Present Status and Future Perspectives

Stroke is the second leading cause of death and a major contributor to disability worldwide. The prevalence of stroke is highest in developing countries, with ischemic stroke being the most common type. Considerable progress has been made in our understanding of the pathophysiology of stroke and the underlying mechanisms leading to ischemic insult. Stroke therapy primarily focuses on restoring blood flow to the brain and treating stroke-induced neurological damage. Lack of success in recent clinical trials has led to significant refinement of animal models, focus-driven study design and use of new technologies in stroke research. Simultaneously, despite progress in stroke management, post-stroke care exerts a substantial impact on families, the healthcare system and the economy. Improvements in pre-clinical and clinical care are likely to underpin successful stroke treatment, recovery, rehabilitation and prevention. In this review, we focus on the pathophysiology of stroke, major advances in the identification of therapeutic targets and recent trends in stroke research.

Clinical considerations and assessment of risk factors when choosing endovascular thrombectomy for acute stroke

INTRODUCTION

The advent of endovascular thrombectomy (EVT) has been a game changer for the management of acute ischemic stroke due to large vessel occlusion. However, the selection of suitable candidates for EVT remains a significant challenge.

AREAS COVERED

This review focuses on the clinical, radiological, and procedural considerations for EVT in acute stroke that assist in optimal patient selection.

EXPERT OPINION

All patients presenting with significant clinical deficits with treatable occlusions, who have salvageable brain tissue at presentation might benefit from treatment up to twenty-four hours from symptom onset. Neuroimaging tools form the backbone for this decision making.

Chinese Stroke Association guidelines for clinical management of cerebrovascular disorders: executive summary and 2019 update of clinical management of ischaemic cerebrovascular diseases

Aim

Stroke is the leading cause of disability and death in China. Ischaemic stroke accounts for about 60%–80% of all strokes. It is of considerable significance to carry out multidimensional management of ischaemic cerebrovascular diseases. This evidence-based guideline aims to provide the latest detailed and comprehensive recommendations on the diagnosis, treatment and secondary prevention of ischaemic cerebrovascular diseases.

Methods

We had performed comprehensive searches of MEDLINE (via PubMed) (before 30 June 2019), and integrated the relevant information into charts and distributed to the writing group. Writing group members discussed and determined the recommendations through teleconference. We used the level of evidence grading algorithm of Chinese Stroke Association to grade each recommendation. The draft was reviewed by the Guideline Writing Committee of Chinese Stroke Association Stroke and finalised. This guideline is fully updated every 3 years.

Results

This evidence-based guideline is based on the treatment, care and prevention of ischaemic cerebrovascular diseases, which emphasises on pathogenesis evaluation, intravenous thrombolysis, endovascular therapy, antiplatelet therapy, prevention and treatment of complications, and risk factor management.

Conclusions

This updated guideline presents a framework for the management of ischaemic cerebrovascular diseases. Timely first-aid measures, professional care in the acute stage, and proactive secondary prevention will be helpful to patients.

Expansion of the dimensions in the current management of acute ischemic stroke

Stroke is the fifth leading cause of death in the United States with a huge burden on health care. Acute ischemic stroke (AIS) accounts for 87% of all stroke. The use of thrombolytic agents in AIS treatment is well known since 1950 but no FDA approval until 1996, due to lack of strong evidence showing benefits outweigh the risk of intracranial hemorrhage. The NINDS trial led to the approval of intravenous tissue plasminogen activator treatment (IV recombinant tPA) within 3 h of stroke. Due to this limitation of 3-4.5 h. window, evolution began in the development of effective endovascular therapy (EVT). Multiple trials were unsuccessful in establishing the strong evidence for effectiveness of EVT. In 2015, MR CLEAN trial made progress and showed improved outcomes with EVT in AIS patients with large vessel occlusion (LVO), with 6-h window period. In 2018, two major trials-DAWN and DEFUSE 3-along with few other trials had shown improved outcomes with EVT and stretched window period from 6 to 24 h. AHA Stroke Council is constantly working to provide focused guidelines and recommendations in AIS management since 2013. SVIN had started the initiative "Mission Thrombectomy-2020" to increase global EVT utilization rate 202,000 procedures by 2020. Physicians are using safer and easier approach like brachial and radial approach for EVT. TeleNeurology and artificial intelligence also played a significant role in increasing the availability of IV recombinant tPA in AIS treatment in remote hospitals and also in screening, triaging and identifying LVO patients for EVT. In this review article, we aim to describe the history of stroke management along with the new technological advancements in AIS treatment.

Endovascular treatment or general treatment: how should acute ischemic stroke patients choose to benefit from them the most?: A systematic review and meta-analysis

BACKGROUND

Acute ischemic stroke due to large-vessel occlusion is a leading cause of death and disability, and therapeutic time window was limited to 4.5 hour when treated with intravenous thrombolysis. It has been acknowledged that endovascular treatment (EVT) is superior to general treatment (only medication, including intravenous recombinant tissue plasminogen activator (rt-PA)) in improving the outcome of AIS since 2015. However, the benefits were limited to improvement of functional outcomes and functional independence. Hence, this meta-analysis was conducted to summarize the benefits of EVT for acute ischemic stroke, explore underlying indications of EVT for AIS patients and suggest implications for clinical practice and future research.

METHODS

A search was performed to identify eligible studies in PubMed, Scopus and Web of Science updated to February 5, 2019. Functional outcomes, the modified Rankin Scale (mRS) 0-1, mRS 0-2, all-cause mortality, symptomatic intracerebral hemorrhage and asymptomatic intracerebral hemorrhage (aICH) at 90 days were selected as outcomes. Data was pooled to calculate the odds ratio (OR) and 95% confidence interval (CI). Heterogeneity, subgroup analysis, sensitivity analysis and publication bias were also performed in this meta-analysis.

RESULTS

Eighteen studies comprising 3831 patients were included and analyzed in this meta-analysis. In comparison with general treatment, improved functional outcomes (mRS 0-1: OR = 1.68, 95% CI = 1.43-1.97, inconsistency index [I = 57%, P < .00001; mRS 0-2: OR = 1.78, 95% CI = 1.55-2.03, I = 69%, P < .00001), reduced risk of all-cause mortality (OR = 0.82, 95% CI = 0.70-0.98, I = 27%, P = .03) but higher risk of aICH (OR = 1.43, 95% CI = 1.05-1.95, I = 0%, P = .02) at 90 days were found in AIS patients treated with EVT. Age < 70, National Institutes of Health Stroke Scale ≥20 and maximum delay for invention>5 hours could improve clinical outcomes following EVT. In sensitivity analysis, it showed that 2 studies had a great influence on the pooled ORs. No potential publication bias was found in this meta-analysis.

CONCLUSION

Taken together, EVT, which led to improved functional outcomes and decreased risk of death, is superior to general treatment for AIS patients with age < 70, National Institutes of Health Stroke Scale ≥20 and maximum delay for invention>5 hours. Moreover, it suggests that "with mechanical thrombectomy" is potential favorable factor for improving aICH in comparison with general treatment.

Border Zones of Evidence: How Non-evidence Based Factors Influence Evidence Generation and Clinical Practice in Stroke Medicine

The interpretation of the results of clinical trials should be done by examining the finer prints of extraneous factors such as stopping rules, interim analysis, intricacies of patient selection, and the rationale of decisions that lead to non-prespecified termination. This can be done only by critical education in the art and science of interpretation of evidence emerging from clinical trials. The pioneering pivotal studies, namely, NINDS rtPA and ECASS III trials, hold disproportionate influence in determining the contours of the subsequent fate of clinical trials and treatment guidelines. It needs to be recognized that the pooling of studies using dissimilar trial designs, notwithstanding similar patient profiles, would undermine the positive signal emerging from the studies that have used better selection methodologies to homogenize the study population.

Urokinase Plasminogen Activator: A Potential Thrombolytic Agent for Ischaemic Stroke

Stroke continues to be one of the leading causes of mortality and morbidity worldwide. Restoration of cerebral blood flow by recombinant plasminogen activator (rtPA) with or without mechanical thrombectomy is considered the most effective therapy for rescuing brain tissue from ischaemic damage, but this requires advanced facilities and highly skilled professionals, entailing high costs, thus in resource-limited contexts urokinase plasminogen activator (uPA) is commonly used as an alternative. This literature review summarises the existing studies relating to the potential clinical application of uPA in ischaemic stroke patients. In translational studies of ischaemic stroke, uPA has been shown to promote nerve regeneration and reduce infarct volume and neurological deficits. Clinical trials employing uPA as a thrombolytic agent have replicated these favourable outcomes and reported consistent increases in recanalisation, functional improvement and cerebral haemorrhage rates, similar to those observed with rtPA. Single-chain zymogen pro-urokinase (pro-uPA) and rtPA appear to be complementary and synergistic in their action, suggesting that their co-administration may improve the efficacy of thrombolysis without affecting the overall risk of haemorrhage. Large clinical trials examining the efficacy of uPA or the combination of pro-uPA and rtPA are desperately required to unravel whether either therapeutic approach may be a safe first-line treatment option for patients with ischaemic stroke. In light of the existing limited data, thrombolysis with uPA appears to be a potential alternative to rtPA-mediated reperfusive treatment due to its beneficial effects on the promotion of revascularisation and nerve regeneration.

Health Utility Weighting of the Modified Rankin Scale: A Systematic Review and Meta-analysis

IMPORTANCE

The utility-weighted modified Rankin Scale (UW-mRS) has been proposed as a patient-centered alternative primary outcome for stroke clinical trials. However, to date, there is no clear consensus on an approach to weighting the mRS.

OBJECTIVE

To characterize the between-study variability in utility weighting of the mRS in a population of patients who experienced stroke and its implications when applied to the results of a clinical trial.

DATA SOURCES

In this systematic review and meta-analysis, MEDLINE, Embase, and PsycINFO were searched from January 1987 through May 2019 using major search terms for stroke, health utility, and mRS.

STUDY SELECTION

Original research articles published in English were reviewed. Included were studies with participants 18 years or older with ischemic or hemorrhagic stroke, transient ischemic attack, or subarachnoid hemorrhage, with mRS scores and utility weights evaluated concurrently. A total of 5725 unique articles were identified. Of these, 283 met criteria for full-text review, and 24 were included in the meta-analysis.

DATA EXTRACTION AND SYNTHESIS

PRISMA guidelines for systematic review were followed. Data extraction was performed independently by multiple researchers. Data were pooled using mixed models.

MAIN OUTCOMES AND MEASURES

The mean utility weights and 95% CIs were calculated for each mRS score and health utility scale. Geographic differences in weighting for the EuroQoL 5-dimension (EQ-5D) and Stroke Impact Scale-based UW-mRS were explored using inverse variance-weighted linear models. The results of 18 major acute stroke trials cited in current guidelines were then reanalyzed using the UW-mRS weighting scales identified in the systematic review.

RESULTS

The meta-analysis included 22 389 individuals; the mean (SD) age of participants was 65.9 (4.0) years, and the mean (SD) proportion of male participants was 58.2% (7.5%). For all health utility scales evaluated, statistically significant differences were observed between the mean utility weights by mRS score. For studies using an EQ-5D-weighted mRS, between-study variance was higher for worse (mRS 2-5) compared with better (mRS 0-1) scores. Of the 18 major acute stroke trials with reanalyzed results, 3 had an unstable outcome when using different UW-mRSs.

CONCLUSIONS AND RELEVANCE

Multiple factors, including cohort-specific characteristics and health utility scale selection, can influence mRS utility weighting. If the UW-mRS is selected as a primary outcome, the approach to weighting may alter the results of a clinical trial. Researchers using the UW-mRS should prospectively and concurrently obtain mRS scores and utility weights to characterize study-specific outcomes.

Safety and Efficacy of Intra-arterial Urokinase After Failed, Unsuccessful, or Incomplete Mechanical Thrombectomy in Anterior Circulation Large-Vessel Occlusion Stroke

Importance

Achieving complete reperfusion is a key determinant of good outcome in patients treated with mechanical thrombectomy (MT). However, data on treatments geared toward improving reperfusion after incomplete MT are sparse.

Objective

To determine whether administration of intra-arterial urokinase is safe and improves reperfusion after failed or incomplete MT.

Design, Setting, and Participants

This observational cohort study included a consecutive sample of patients treated with second-generation MT from January 1, 2010, through August 4, 2017. Data were collected from the prospective registry of a tertiary care stroke center. Of 1274 patients screened, 69 refused to participate, and 993 met the observational studies inclusion criteria of a large vessel occlusion in the anterior circulation. Data were analyzed from September 1, 2017, through September 20, 2019.

Intervention

One hundred patients received intra-arterial urokinase after failed or incomplete MT using manual microcatheter injections.

Main Outcomes and Measures

Primary safety outcome was the occurrence of symptomatic intracranial hemorrhage (sICH) according to the Prolyse in Acute Cerebral Thromboembolism II criteria. Secondary end points included 90-day mortality and 90-day functional independence (defined as modified Rankin Scale score of ≤2). Efficacy was evaluated angiographically, applying the Thrombolysis in Cerebral Infarction (TICI) scale.

Results

After exclusion of patients with posterior circulation strokes and those treated with intra-arterial thrombolytics only, 993 patients were included in the final analyses (median age, 74.6 [interquartile range, 62.6-82.2] years; 505 [50.9%] women). Additional intra-arterial urokinase was administered in 100 patients (10.1%). The most common reason for administering intra-arterial urokinase was incomplete reperfusion (TICI<3) after MT (53 [53.0%]). After adjusting for baseline characteristics underlying case selection, intra-arterial urokinase was not associated with an increased risk of sICH (adjusted odds ratio [aOR], 0.81; 95% CI, 0.31-2.13) or 90-day mortality (aOR, 0.78; 95% CI, 0.43-1.40). Among 53 cases of partial or near-complete reperfusion and treated with intra-arterial urokinase, 32 (60.4%) had early reperfusion improvement, and 18 of 53 (34.0%) had an improvement in TICI grade. Correspondingly, patients treated with intra-arterial urokinase had higher rates of functional independence after adjusting for the selection bias favoring a priori poor TICI grades in the intra-arterial urokinase group (aOR, 1.93; 95% CI, 1.11-3.37).

Conclusions and Relevance

In selected patients, adjunctive treatment with intra-arterial urokinase during or after MT was safe and improved angiographic reperfusion. Systemic evaluation of this approach in a multicenter prospective registry or a randomized clinical trial seems warranted.

Protein-Carbon Dot Nanohybrid-Based Early Blood-Brain Barrier Damage Theranostics

For effective treatment of ischemic cerebral thrombosis, it is of great significance to find a facile way in assessing the early damage of blood-brain barrier (BBB) after ischemic stroke during thrombolysis by integrating thrombolytic agents with fluorescent materials. Herein, a novel type of protein-carbon dot  nanohybrids is reported by the incorporation of carbon dots on thrombolytic agents through covalent linkage. Both in vitro and ex vivo fluorescence imaging measurements have demonstrated remarkable imaging effects in the brain of transient middle cerebral artery occlusion mice. Besides, the outstanding thrombolytic capacity of the nanohybrids was determined by in vitro thrombolysis tests. As one of the few reports of the construction of thrombolytic agents and fluorescent nanomaterials, the nanohybrids retain thrombolysis ability and fluorescent traceability simultaneously. It may provide a promising indicator for early BBB damage and thrombolytic agent distribution to estimate the possibility of symptomatic intracranial hemorrhage after thrombolysis and supply tissue window evidence for clinical thrombolytic agent application.

Efficacy of Minimally Invasive Intervention in Patients With Acute Cerebral Infarction

Our aim was to explore the efficacy of minimally invasive intervention in patients with acute cerebral infarction (ACI). Seventy patients with ACI were randomized into either an experimental group or a control group. In addition to the regular treatment, patients in the control group also received intravenous thrombolysis with urokinase, while patients in the other group underwent percutaneous transluminal cerebral angioplasty and stenting. Metrics included recanalization rate, serum cytokines, fibrinolytic markers, and 36-Item Short Form Health Survey score and were compared between the 2 groups. After treatment, patients in the experimental group had better recanalization rate, higher SF-36 score and greater levels of vascular endothelial growth factors, neurotrophic factors, and nerve growth factors than those in the control group. Moreover, the values of fibrinolytic markers changed significantly in both groups after treatment. Compared with the control group, the experimental group had lower levels of tissue polypeptide antigen and plasminogen activator inhibitor-1 and a higher level of von Willebrand factor after treatment. In sum, the application of minimally invasive intervention can increase both the recanalization rate and concentrations of serum cytokines, can improve the quality of life in patients with ACI, and has small impacts on the fibrinolytic system in patients.

National Institutes of Health Stroke Scale: An Alternative Primary Outcome Measure for Trials of Acute Treatment for Ischemic Stroke

Supplemental Digital Content is available in the text.

The modified Rankin Scale (mRS) at 3 months is the most commonly used primary outcome measure in stroke treatment trials, but it lacks specificity and requires long-term follow-up interviews, which consume time and resources. An alternative may be the National Institutes of Health Stroke Scale (NIHSS), early after stroke. Our aim was to evaluate whether the NIHSS assessed within 1 week after treatment could serve as a primary outcome measure for trials of acute treatment for ischemic stroke.

Guidelines for the Early Management of Patients With Acute Ischemic Stroke: 2019 Update to the 2018 Guidelines for the Early Management of Acute Ischemic Stroke: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association

Background and Purpose- The purpose of these guidelines is to provide an up-to-date comprehensive set of recommendations in a single document for clinicians caring for adult patients with acute arterial ischemic stroke. The intended audiences are prehospital care providers, physicians, allied health professionals, and hospital administrators. These guidelines supersede the 2013 Acute Ischemic Stroke (AIS) Guidelines and are an update of the 2018 AIS Guidelines. Methods- Members of the writing group were appointed by the American Heart Association (AHA) Stroke Council's Scientific Statements Oversight Committee, representing various areas of medical expertise. Members were not allowed to participate in discussions or to vote on topics relevant to their relations with industry. An update of the 2013 AIS Guidelines was originally published in January 2018. This guideline was approved by the AHA Science Advisory and Coordinating Committee and the AHA Executive Committee. In April 2018, a revision to these guidelines, deleting some recommendations, was published online by the AHA. The writing group was asked review the original document and revise if appropriate. In June 2018, the writing group submitted a document with minor changes and with inclusion of important newly published randomized controlled trials with >100 participants and clinical outcomes at least 90 days after AIS. The document was sent to 14 peer reviewers. The writing group evaluated the peer reviewers' comments and revised when appropriate. The current final document was approved by all members of the writing group except when relationships with industry precluded members from voting and by the governing bodies of the AHA. These guidelines use the American College of Cardiology/AHA 2015 Class of Recommendations and Level of Evidence and the new AHA guidelines format. Results- These guidelines detail prehospital care, urgent and emergency evaluation and treatment with intravenous and intra-arterial therapies, and in-hospital management, including secondary prevention measures that are appropriately instituted within the first 2 weeks. The guidelines support the overarching concept of stroke systems of care in both the prehospital and hospital settings. Conclusions- These guidelines provide general recommendations based on the currently available evidence to guide clinicians caring for adult patients with acute arterial ischemic stroke. In many instances, however, only limited data exist demonstrating the urgent need for continued research on treatment of acute ischemic stroke.

Early Prediction of Malignant Brain Edema After Ischemic Stroke

Background and Purpose- Malignant brain edema after ischemic stroke has high mortality but limited treatment. Therefore, early prediction is important, and we systematically reviewed predictors and predictive models to identify reliable markers for the development of malignant edema. Methods- We searched Medline and Embase from inception to March 2018 and included studies assessing predictors or predictive models for malignant brain edema after ischemic stroke. Study quality was assessed by a 17-item tool. Odds ratios, mean differences, or standardized mean differences were pooled in random-effects modeling. Predictive models were descriptively analyzed. Results- We included 38 studies (3278 patients) with 24 clinical factors, 7 domains of imaging markers, 13 serum biomarkers, and 4 models. Generally, the included studies were small and showed potential publication bias. Malignant edema was associated with younger age (n=2075; mean difference, -4.42; 95% CI, -6.63 to -2.22), higher admission National Institutes of Health Stroke Scale scores (n=807, median 17-20 versus 5.5-15), and parenchymal hypoattenuation >50% of the middle cerebral artery territory on initial computed tomography (n=420; odds ratio, 5.33; 95% CI, 2.93-9.68). Revascularization (n=1600, odds ratio, 0.37; 95% CI, 0.24-0.57) were associated with a lower risk for malignant edema. Four predictive models all showed an overall C statistic >0.70, with a risk of overfitting. Conclusions- Younger age, higher National Institutes of Health Stroke Scale, and larger parenchymal hypoattenuation on computed tomography are reliable early predictors for malignant edema. Revascularization reduces the risk of malignant edema. Future studies with robust design are needed to explore optimal cutoff age and National Institutes of Health Stroke Scale scores and to validate and improve existing models.