Endovascular treatment versus medical care alone for ischaemic stroke: systematic review and meta-analysis

2018 Guidelines for the Early Management of Patients With 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 for clinicians caring for adult patients with acute arterial ischemic stroke in a single document. The intended audiences are prehospital care providers, physicians, allied health professionals, and hospital administrators. These guidelines supersede the 2013 guidelines and subsequent updates.

METHODS

Members of the writing group were appointed by the American Heart Association Stroke Council's Scientific Statements Oversight Committee, representing various areas of medical expertise. Strict adherence to the American Heart Association conflict of interest policy was maintained. Members were not allowed to participate in discussions or to vote on topics relevant to their relations with industry. The members of the writing group unanimously approved all recommendations except when relations with industry precluded members voting. Prerelease review of the draft guideline was performed by 4 expert peer reviewers and by the members of the Stroke Council's Scientific Statements Oversight Committee and Stroke Council Leadership Committee. These guidelines use the American College of Cardiology/American Heart Association 2015 Class of Recommendations and Levels of Evidence and the new American Heart Association 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 are based on the best evidence currently available. In many instances, however, only limited data exist demonstrating the urgent need for continued research on treatment of acute ischemic stroke.

Selection criteria for endovascular therapy for acute ischaemic stroke: Are patients missing out?

INTRODUCTION

Endovascular clot retrieval (ECR) following intravenous thrombolysis is superior to intravenous thrombolysis alone for acute stroke with large vessel occlusion. However, trial selection criteria may exclude potentially salvageable patients. We investigated the impact of published selection criteria on the different proportions of patients excluded and clinical outcome.

METHODS

We included patients with anterior circulation stroke treated with ECR from a single centre. Selection criteria from five trials (REVASCAT, EXTEND IA, MR CLEAN, SWIFT PRIME, ESCAPE) and American Stroke Association (ASA) guidelines were applied. We calculated the proportion of patient's ineligible for ECR according to different selection criteria. Clinical benefit and harm were quantified as the number of patients benefiting per 1 patient harmed (NB1H) for each of the 6 applied selection criteria.

RESULTS

One hundred and seventy-eight patients were included. Mean age was 74 (SD 14) years, 60.1% were male, median baseline NIHSS was 17 (IQR 13-21). Patients were hypothetically excluded from ECR: REVASCAT 35.4%, EXTENDA IA 86%, SWIFT PRIME 86%, MR CLEAN 2.3%, ESCAPE 93.3% and ASA 29.2%. The NB1H for included and excluded patients respectively in decreasing order of magnitude: EXTEND IA >100 vs 3, ESCAPE >100 vs 3.4, SWIFT PRIME 10 vs 3.3, REVASCAT 4.4 vs 2.9, MR CLEAN 3.7 vs >100, and ASA 3.7 vs 3.9.

CONCLUSION

We found that criteria from MR CLEAN, ASA and REVASCAT excluded the lowest proportion of patients with comparable NB1H. We believe that these criteria would be reasonable to be utilised for ECR selection.

Leptomeningeal collateral status predicts outcome after middle cerebral artery occlusion

OBJECTIVES

Perfusion through leptomeningeal collateral vessels is a likely pivotal factor in the outcome of stroke patients. We aimed to investigate the effect of collateral status on outcome in a cohort of unselected, consecutive stroke patients with middle cerebral artery occlusion undergoing reperfusion therapy.

MATERIALS AND METHODS

This retrospectively planned analysis was passed on prospectively collected data from 187 consecutive patients with middle cerebral artery occlusion admitted within 4.5 hours to one center and treated with intravenous thrombolysis alone (N = 126), mechanical thrombectomy alone (N = 5), or both (N = 56) from May 2009 to April 2014. Non-contrast CT (NCCT) and computed tomography angiography (CTA) were provided on admission and NCCT repeated at 24 hours. Collateral status was assessed based on the initial CTA. Hemorrhagic transformation was evaluated on the 24-hour NCCT and according to European Cooperative Acute Stroke Study (ECASS) criteria. Modified Rankin Scale score was assessed at 90 days, and mortality at 1 year.

RESULTS

At 90 days, median (IQR) modified Rankin Scale score in patients with poor collateral status was 4 (3-6) compared to 2 (1-4) in patients with good collateral status (P < .0001). Patients with poor collateral status were less likely to achieve a good 90-day outcome (modified Rankin Scale score 0-2) (Adjusted odds ratio 0.27, 95% CI: 0.09-0.86). During the first year, 40.9% of patients with poor collateral status died vs 18.2% of the remaining population (P = .001).

CONCLUSIONS

Leptomeningeal collateral status predicts functional outcome, mortality, and hemorrhagic transformation following middle cerebral artery occlusion.

Use of a mechanical thrombectomy device to treat early hepatic artery thrombosis after orthotopic liver transplant

Hepatic artery thrombosis (HAT) is a major cause of morbidity and mortality after orthotopic liver transplantation, occurring in 5% of cases (Piardi et al, 2016). HAT is the second main cause of graft loss after primary nonfunction, the leading cause of graft failure in the immediate postoperative period (<1 month), and is associated with a mortality rate of up to 60% without intervention (Piardi et al, 2016; Pareja et al., 2010; Crossin et al., 2003). Although retransplantation is the preferred therapy, the limited availability of donor organs can necessitate urgent, alternative treatment. These patients present physicians with an often-severe clinical picture, which requires consideration of endovascular approaches as opposed to the more traditional, invasive surgical interventions. The following case study presents a novel mechanical therapy that uses an endovascular approach for revascularization—a stent retriever device.

Minor stroke due to large artery occlusion. When is intravenous thrombolysis not enough? Results from the SITS International Stroke Thrombolysis Register

Purpose

Beyond intravenous thrombolysis, evidence is lacking on acute treatment of minor stroke caused by large artery occlusion. To identify candidates for additional endovascular therapy, we aimed to determine the frequency of non-haemorrhagic early neurological deterioration in patients with intravenous thrombolysis-treated minor stroke caused by occlusion of large proximal and distal cerebral arteries. Secondary aims were to establish risk factors for non-haemorrhagic early neurological deterioration and report three-month outcomes in patients with and without non-haemorrhagic early neurological deterioration.

Method

We analysed data from the SITS International Stroke Thrombolysis Register on 2553 patients with intravenous thrombolysis-treated minor stroke (NIH Stroke Scale scores 0-5) and available arterial occlusion data. Non-haemorrhagic early neurological deterioration was defined as an increase in NIH Stroke Scale score ≥4 at 24 h, without parenchymal hematoma on follow-up imaging within 22-36 h.

Findings

The highest frequency of non-haemorrhagic early neurological deterioration was seen in 30% of patients with terminal internal carotid artery or tandem occlusions (internal carotid artery + middle cerebral artery) (adjusted odds ratio: 10.3 (95% CI 4.3-24.9), p < 0.001) and 17% in extracranial carotid occlusions (adjusted odds ratio 4.3 (2.5-7.7), p < 0.001) versus 3.1% in those with no occlusion. Proximal middle cerebral artery-M1 occlusions had non-haemorrhagic early neurological deterioration in 9% (adjusted odds ratio 2.1 (0.97-4.4), p = 0.06). Among patients with any occlusion and non-haemorrhagic early neurological deterioration, 77% were dead or dependent at three months.

Conclusions

Patients with minor stroke caused by internal carotid artery occlusion, with or without tandem middle cerebral artery involvement, are at high risk of disabling deterioration, despite intravenous thrombolysis treatment. Acute vessel imaging contributes usefully even in minor stroke to identify and consider endovascular treatment, or intensive monitoring at a comprehensive stroke centre, for patients at high risk of neurological deterioration.

Acute treatment of stroke due to spontaneous calcified cerebral emboli causing large vessel occlusion

INTRODUCTION

Calcified cerebral emboli (CCE) are rarely responsible for large vessel occlusion (LVO) in acute anterior stroke, and therefore therapeutic experience is scarce. We sought to expand current knowledge upon therapeutic options with three new cases and a review of current literature.

METHODS

Systematic search of patients with acute anterior stroke due to LVO in one comprehensive stroke center throughout a 4 year period. Literature search for reported cases of CCE.

RESULTS

In total, 21 cases (19 found in literature and 3 from our institution) are reported with a median age of 72 years (interquartile range [IQR] 63-80). Eleven patients were treated acutely, 4 of them with endovascular thrombectomy (EVT). Middle cerebral artery (MCA) M1 was the most affected segment and large artery atherosclerosis (LAA) and cardioembolism (CE) was causative in 41% of cases. EVT was significantly superior to intravenous recombinant tissue plasminogen activator (rtPA) at p = .048 (Fisher's exact test, chi square 6.7).

CONCLUSIONS

Given the small sample reported in literature and no reported randomised studies, definitive recommendations could not be reached. However, considering thrombus composition, thrombolysis is most probably not sufficient and priority should be given to EVT.

Chinese herbal medicine Dengzhan Xixin injection for acute ischemic stroke: A systematic review and meta-analysis of randomised controlled trials

OBJECTIVE

To evaluate the effectiveness and safety of Chinese herbal medicine Dengzhan Xixin (Erigeron breviscapus) injection for acute ischemic stroke.

DESIGN

Systematic review and meta-analysis (CRD42016038413, http://www.crd.york.ac.uk/PROSPERO).

METHODS

Six electronic databases were searched from inception to March 2016 for randomised controlled trials (RCTs) of Dengzhan Xixin (DZXX) injection for acute ischemic stroke. The methodological quality of RCTs was assessed by the Cochrane risk of bias tool.

DATA SYNTHESIS

was performed using RevMan 5.3 and was presented with mean difference (MD) or relative risk (RR) and their 95% confidence interval (CI). A summary of finding table was generated by GRADEpro (version 3.6).

RESULTS

Twenty-five RCTs with 2498 participants were included and all trials adopted conventional therapy (CT) in both arms. Most of the studies had high risk of bias. The addition of DZXX to CT showed no significant benefit on death (RR 0.27, 95% CI 0.05-1.63) within the treatment period (14-35 d), but showed higher Barthel index score (MD 10.20, 95% CI 8.16-12.25), lower neurological function deficit score (MD -3.99, 95% CI -5.68 to -2.30, by NFDS; MD -1.67, 95% CI -2.59 to -0.76, by NIHSS), and lower treatment failure (RR 0.40, 95% CI 0.31-0.52). Thirteen trials (52%) reported the outcome of adverse events, but no serious adverse events were reported.

CONCLUSION

Low quality evidence implied that DZXX injection appeared to improve neurological function in patients with acute ischemic stroke. However, this potential benefit should be further studied in large, rigorous trials.

Ultrasound and Intra-Clot Microbubbles Enhanced Catheter-Directed Thrombolysis in Vitro and in Vivo

Insufficient penetration of microbubbles (MBs) into the vessel-obstructing thrombi significantly reduces the effectiveness of ultrasound thrombolysis (UT). The widely performed catheter-directed therapy (CDT) makes it possible to increase the local concentration of MBs in the clot. In an occluded vessel with a bypass, treatment of fresh human whole blood clots with CDT-based UT (intra-clot injection of MBs and urokinase, with ultrasound exposure) resulted in a significantly higher percentage of weight loss (35.32 ± 15.42%), compared with CDT alone (19.64 ± 4.71%), non-CDT-based UT (systemic administration of urokinase and MBs, with ultrasound exposure, 8.79 ± 3.02%) and systemic thrombolysis (7.90 ± 2.14). Ultrasound and intra-clot MB enhancement of CDT was further confirmed by a rabbit IVC thrombolysis study, where CDT-based UT resulted in significantly more effective thrombolysis compared with CDT alone. In summary, combining CDT with intra-clot MB-induced acoustic cavitation can improve thrombolysis.

Stroke in a resource-constrained hospital in Madagascar

Background

Stroke is reported as the most frequent cause of in-hospital death in Madagascar. However, no descriptive data on hospitalized stroke patients in the country have been published. In the present study, we sought to investigate the feasibility of collecting data on stroke patients in a resource-constrained hospital in Madagascar. We also aimed to characterize patients hospitalized with stroke.

Methods

We registered socio-demographics, clinical characteristics, and early outcomes of patients admitted for stroke between 23 September 2014 and 3 December 2014. We used several validated scales for the evaluation. Stroke severity was measured by the National Institutes of Health Stroke Scale (NIHSS), disability by the modified Rankin Scale (mRS), and function by the Barthel Index (BI).

Results

We studied 30 patients. Sixteen were males. The median age was 62.5 years (IQR 58–67). The NIHSS and mRS were completed for all of the patients, and BI was used for the survivors. Three patients received a computed tomography (CT) brain scan. The access to laboratory investigations was limited. Electrocardiographs (ECGs) were not performed. The median NIHSS score was 16.5 (IQR 10–35). The in-hospital stroke mortality was 30%. At discharge, the median mRS score was 5 (IQR 4–6), and the median BI score was 45 (IQR 0–72.5).

Conclusions

Although the access to brain imaging and supporting investigations was deficient, this small-scale study suggests that it is feasible to collect essential data on stroke patients in a resource-constrained hospital in Madagascar. Such data should be useful for improving stroke services and planning further research. The hospitalized stroke patients had severe symptoms. The in-hospital stroke mortality was high. At discharge, the disability category was high, and functional status low.

Recent Trends in Clot Retrieval Devices: A Review

Stroke is the second leading cause of death worldwide and in Europe. Even with gold standard medical management of acute ischemic stroke, which is intravenous (IV) thrombolysis by administration of recombinant tissue plasminogen activator (rt-PA), the mortality rate remains the same. Intra-arterial (IA) thrombolysis therapy also did not achieve significant results and was not approved by the US Food and Drug Administration (FDA) because of limited sample size. This encouraged scientists and engineers to develop endovascular clot retrieval devices for the mechanical recanalization of the occluded arteries in stroke patients. Although the initial designs of clot retrieval devices failed, efforts to improve these devices continue. Recently clot retrieval devices were approved by the FDA as first-line treatment along with IV rt-PA. This article gives an in-depth review of different clot retrieval devices which includes MERCI (the first), the Penumbra Aspiration System, EmboTrap^®II, stent retrievers, and the way forward with the new FDA clearance of the devices as first-line treatment for acute ischemic stroke along with IV rt-PA. The review also includes a comparison of clot retrieval devices to gold standard treatment.

Revolution in acute ischaemic stroke care: a practical guide to mechanical thrombectomy

Rapid, safe and effective arterial recanalisation to restore blood flow and improve functional outcome remains the primary goal of hyperacute ischaemic stroke management. The benefit of intravenous thrombolysis with recombinant tissue-type plasminogen activator for patients with severe stroke due to large artery occlusion is limited; early recanalisation is generally less than 30% for carotid, proximal middle cerebral artery or basilar artery occlusion. Since November 2014, nine positive randomised controlled trials of mechanical thrombectomy for large vessel occlusion in the anterior circulation have led to a revolution in the care of patients with acute ischaemic stroke. Its efficacy is unmatched by any previous therapy in stroke medicine, with a number needed to treat of less than 3 for improved functional outcome. With effectiveness shown beyond any reasonable doubt, the key challenge now is how to implement accessible, safe and effective mechanical thrombectomy services. This review aims to provide neurologists and other stroke physicians with a summary of the evidence base, a discussion of practical aspects of delivering the treatment and future challenges. We aim to give guidance on some of the areas not clearly described in the clinical trials (based on evidence where available, but if not, on our own experience and practice) and highlight areas of uncertainty requiring further research.

The Chinese Stroke Association scientific statement: intravenous thrombolysis in acute ischaemic stroke

The most effective medical treatment for acute ischaemic stroke (AIS) is to offer intravenous thrombolysis during the ultra-early period of time after the onset. Even based on the Consensus of Chinese Experts on Intravenous Thrombolysis for AIS in 2012 and 2014 Chinese Guidelines on the Diagnosis and Treatment of AIS, the rate of thrombolysis for AIS in China remained around 2.4%, and the rate of intravenous tissue plasminogen activator usage was only about 1.6% in real world. The indication of thrombolysis for AIS has been expanded, and contraindications have been reduced with recently published studies. In order to facilitate the standardisation of treating AIS, improve the rate of thrombolysis and benefit patients who had a stroke, Chinese Stroke Association has organised and developed this scientific statement.

The Taking Charge After Stroke (TaCAS) study protocol: a multicentre, investigator-blinded, randomised controlled trial comparing the effect of a single Take Charge session, two Take Charge sessions and control intervention on health-related quality of life 12 months after stroke for non-Māori, non-Pacific adult New Zealanders discharged to community living

INTRODUCTION

Stroke is one of the leading causes of disability worldwide. Recent data support the possibility that person-centred, self-management interventions can reduce dependence after stroke. However, there is limited information on the generalisability and optimum dose of these interventions.

METHODS

The Taking Charge After Stroke (TaCAS) study is a multicentre, investigator-blinded, randomised controlled trial recruiting 400 participants following acute stroke from seven hospitals in New Zealand. All patients discharged to community living who have ongoing symptoms at time of discharge (modified Rankin scale>0) will be eligible. Participants will be randomly assigned to one Take Charge session, two Take Charge sessions 6 weeks apart or control.

OUTCOMES

The primary outcome will be the Physical Component Summary score of the Short-Form 36 at 12 months post stroke. Secondary outcomes will include dependence (modified Rankin scale), performance in activities of daily living (Barthel Index) and carer strain (Caregiver Strain Index), at 6 and 12 months post stroke. All analyses will be conducted on an intention-to-treat basis.

ETHICS AND DISSEMINATION

The TaCAS study is funded by a Health Research Council of New Zealand grant. It has been approved by the Central Health and Disability Ethics Committee (15/CEN/115). Results will be published and presented at relevant stroke meetings within New Zealand and internationally, informing the use of a self-management intervention after stroke.

TRIAL REGISTRATION

Australia and New Zealand Clinical Trials Registry ACTRN12615001163594. Date registered 02-11-2015. Medical Research Institute of New Zealand Registry TCS01. Universal trial number U1111-1171-4127.

Outcomes of Endovascular Thrombectomy with and without Thrombolysis for Acute Large Artery Ischaemic Stroke at a Tertiary Stroke Centre

BACKGROUND AND PURPOSE

Endovascular thrombectomy (EVT) improves the functional outcome when added to best medical therapy, including alteplase, in patients with acute ischaemic stroke secondary to large vessel occlusion (LVO) in the anterior circulation. However, the evidence for EVT in alteplase-ineligible patients is less compelling. It is also uncertain whether alteplase is necessary in patients with successful recanalization by EVT, as the treatment effect of EVT may be so powerful that bridging alteplase may not add to efficacy and may compromise safety by increasing bleeding risks. We aimed to survey the proportion of patients suitable for EVT who are alteplase-ineligible and to compare the safety and effectiveness of standard care of acute large artery ischaemic stroke by EVT plus thrombolysis with that of EVT alone in a tertiary hospital clinical stroke service.

METHODS

We performed a retrospective analysis of acute ischaemic stroke patients treated with EVT at our centre between October 2013 and April 2016, based on a registry with prospective and consecutive patient collection. Individual patient records were retrieved for review. Significant early neurological improvement was defined as a NIHSS score of 0-1, or a decrease from baseline of ≤8, at 24 h after stroke onset.

RESULTS

Fifty patients with acute ischaemic stroke secondary to LVO in the anterior circulation received EVT in this period, of whom 21 (42%) received concurrent alteplase and 29 (58%) EVT alone. The 2 groups had similar baseline characteristics and similar outcomes. Significant neurological improvement at 24 h occurred in 47.6% of the patients with EVT and bridging alteplase and in 51.7% of the patients with EVT alone (p = 0.774). Mortality during acute hospitalization was 20% for the bridging alteplase group versus 7.1% for EVT alone (p = 0.184). Intracranial haemorrhage rates were 14.3% for bridging alteplase versus 20.7% for EVT alone (p = 0.716). Local complications, groin haematoma (23.8 vs. 10.3%) and groin pseudoaneurysms (4.8 vs. 0%) (p = 0.170), were not significantly different.

CONCLUSION

Our study highlights the relatively large proportion of patients suitable for EVT who have a contraindication to alteplase and raises the hypothesis that adding alteplase to successful EVT may not be necessary to optimize functional outcome. The results are consistent with observational data from other endovascular centres and support a randomised controlled trial of EVT versus EVT with bridging alteplase.

Prediction of Stroke Subtype and Recanalization Using Susceptibility Vessel Sign on Susceptibility-Weighted Magnetic Resonance Imaging

Supplemental Digital Content is available in the text.

Background and Purpose—

The susceptibility vessel sign (SVS) is a hypointense signal visualized because of the susceptibility effect of thrombi, sensitively detected on susceptibility-weighted magnetic resonance imaging. The relationship of SVS parameters with the stroke subtype and recanalization status after endovascular treatment remains uncertain.

Methods—

The data from 89 patients with acute stroke caused by anterior circulation infarcts who underwent susceptibility-weighted magnetic resonance imaging before endovascular treatment were examined. Independent reviewers, blinded to the stroke subtype and recanalization status, measured the SVS diameter, length, and estimated volume. The intra- and interrater agreements of the SVS parameters were assessed.

Results—

The SVS was identified in 78% of the patients. SVS was more commonly associated with cardioembolism than with noncardioembolism (P=0.01). The SVS diameter (P<0.01) and length (P=0.01) were larger in the cardioembolism group. The SVS diameter was larger in the recanalization group (thrombolysis in cerebral infarction ≥2b) than in the nonrecanalization group (P=0.04). Multivariable analysis revealed that the SVS diameter was an independent predictor of cardioembolism (adjusted odds ratio, 1.97; 95% confidence interval, 1.34–2.90; P<0.01). There was no significant association between the SVS volume and the recanalization status (adjusted odds ratio, 1.003; 95% confidence interval, 0.999–1.006; P=0.12). The optimal cutoff value of the SVS diameter for the cardioembolism was 5.5 mm (sensitivity, 45.6%; specificity, 93.8%).

Conclusions—

Increased SVS diameter on susceptibility-weighted magnetic resonance imaging may predict cardioembolism. No clear association was found between SVS volume and endovascular recanalization.

Loss and recovery of functional connectivity in cultured cortical networks exposed to hypoxia

In the core of a brain infarct, loss of neuronal function is followed by neuronal death within minutes. In an area surrounding the core (penumbra), some perfusion remains. Here, neurons initially remain structurally intact, but massive synaptic failure strongly reduces neural activity. Activity in the penumbra may eventually recover or further deteriorate toward massive cell death. Besides activity recovery, return of brain functioning requires restoration of connectivity. However, low activity has been shown to initiate compensatory mechanisms that affect network connectivity. We investigated the effect of transient hypoxia and compensatory mechanisms on activity and functional connectivity using cultured cortical networks on multielectrode arrays. Networks were exposed to hypoxia of controlled depth (10-90% of normoxia) and duration (6-48 h). First, we determined how hypoxic depth and duration govern activity recovery. Then, we investigated connectivity changes during and after hypoxic incidents, mild enough for activity to recover. Shortly after hypoxia onset, activity and connectivity decreased. Following 4-6 h of ongoing hypoxia, we observed partial recovery. Only if the hypoxic burden was limited did connectivity show further recovery upon return to normoxia. Partial recovery during hypoxia was dominated by restored baseline connections, rather than newly formed ones. Baseline strengths of surviving (persisting or recovered) and lost connections did not differ nor did baseline activity at their "presynaptic" electrodes. However, "postsynaptic" electrodes of surviving connections were significantly more active during baseline than those of lost connections. This implies that recovery during hypoxia reflects an effective mechanism to restore network activity, which does not necessarily conserve prehypoxia connectivity.NEW & NOTEWORTHY Hypoxia reduced the firing rates of cultured neurons. Depending on hypoxic depth and duration, activity recovered during hypoxia and upon return to normoxia. Recovery (partial) during hypoxia was associated with restored baseline connections rather than newly formed ones. Predominantly, baseline connections with most active postsynaptic electrodes recovered, supporting the notion of effective activity homeostasis. This compensatory mechanism remained effective during ~20 h of hypoxia. Beyond 20 h of compensation, loss of activity and connectivity became irreversible.

Neuroprotective strategies and the underlying molecular basis of cerebrovascular stroke

Stroke is a leading cause of disability in the US. Although there has been significant progress in the area of medical and surgical thrombolytic technologies, neuroprotective agents to prevent secondary cerebral injury and to minimize disability remain limited. Only limited success has been reported in preclinical and clinical trials evaluating a variety of compounds. In this review, the authors discuss the most up-to-date information regarding the underlying molecular biology of stroke as well as strategies that aim to mitigate this complex signaling cascade. Results of historical research trials involving N-methyl-d-aspartate and α-amino-3-hydroxy-5-methyl-4-isoxazole propionate receptor antagonists, clomethiazole, antioxidants, citicoline, nitric oxide, and immune regulators have laid the groundwork for current progress. In addition, more recent studies involving therapeutic hypothermia, magnesium, albumin, glyburide, uric acid, and a variety of other treatments have provided more options. The use of neuroprotective agents in combination or with existing thrombolytic treatments may be one of many exciting areas of further development. Although past trials of neuroprotective agents in ischemic stroke have been limited, significant insights into mechanisms of stroke, animal models, and trial design have incrementally improved approaches for future therapies.

Endovascular Treatment of Ischemic Stroke: An Updated Meta-Analysis of Efficacy and Safety

Background:

Recent randomized trials demonstrated the superiority of the mechanical thrombectomy over the best medical treatment in patients with acute ischemic stroke due to an occlusion of arteries of proximal anterior circulation. In this updated meta-analysis, we aimed to summarize the total clinical effects of the treatment, including the last trials.

Methods:

We performed literature search of Randomized Crontrolled Trials (RCTs) published between 2010 and October 2016, comparing endovenous thrombolysis plus mechanical thrombectomy (intervention group) with best medical care alone (control group). We identified 8 trials. Primary outcomes were reduced disability at 90 days from the event and symptomatic intracranial hemorrhage. Statistical analysis was performed pooling data into the 2 groups, evaluating outcome heterogeneity. The Mantel-Haenszel method was used to calculate odds ratios (ORs).

Results:

We analyzed data for 1845 patients (interventional group: 911; control group: 934). Mechanical thrombectomy contributed to a significant reduction in disability rate compared to the best medical treatment alone (OR: 2.087; 95% confidence interval [CI]: 1.718-2.535; P < .001). We calculated that for every 100 treated patients, 16 more participants have a good outcome as a result of mechanical treatment. No significant differences between groups were observed concerning the occurrence of symptomatic hemorrhage (OR: 1.021; 95% CI: 0.641-1.629; P = .739).

Conclusion:

Mechanical thrombectomy contributes to significantly increase the functional benefit of endovenous thrombolysis in patients with acute ischemic stroke caused by arterial occlusion of proximal anterior circulation, without reduction in safety. These findings are relevant for the optimization of the acute stroke management, including the implementation of networks between stroke centers.

Digestive and urologic hemorrhage after intravenous thrombolysis for acute ischemic stroke: Data from a Chinese stroke center

Objective

Intravenous thrombolysis with recombinant tissue plasminogen activator (rt-PA) is considered the most effective treatment method for AIS; however, it is associated with a risk of hemorrhage. We analyzed the risk factors for digestive and urologic hemorrhage during rt-PA therapy.

Methods

We retrospectively analyzed patients with AIS who underwent intravenous thrombolysis with rt-PA during a 5-year period in a Chinese stroke center. Data on the demographics, medical history, laboratory test results, and clinical outcomes were collected.

Results

338 patients with AIS were eligible and included. Logistic regression multivariate analysis showed that gastric catheter was significantly correlated with digestive hemorrhage, while age and urinary catheter were significantly correlated with urologic hemorrhage. Most hemorrhagic events were associated with catheterization after 1 to 24 hours of rt-PA therapy.

Conclusions

In summary, gastric and urinary catheters were correlated with digestive and urologic hemorrhage in patients with AIS undergoing rt-PA therapy. Well-designed controlled studies with large samples are required to confirm our findings.

Distinctive patterns on CT angiography characterize acute internal carotid artery occlusion subtypes

Noninvasive computed tomography angiography (CTA) is widely used in acute ischemic stroke, even for diagnosing various internal carotid artery (ICA) occlusion sites, which often need cerebral digital subtraction angiography (DSA) confirmation. We evaluated whether clinical outcomes vary depending on the DSA-based occlusion sites and explored correlating features on baseline CTA that predict DSA-based occlusion site.We analyzed consecutive patients with acute ICA occlusion who underwent DSA and CTA. Occlusion site was classified into cervical, cavernous, petrous, and carotid terminus segments by DSA confirmation. Clinical and radiological features associated with poor outcome at 3 months (3-6 of modified Rankin scale) were analyzed. Baseline CTA findings were categorized according to carotid occlusive shape (stump, spearhead, and streak), presence of cervical calcification, Willisian occlusive patterns (T-type, L-type, and I-type), and status of leptomeningeal collaterals (LMC).We identified 49 patients with occlusions in the cervical (n = 17), cavernous (n = 22), and carotid terminus (n = 10) portions: initial NIH Stroke Scale (11.4 ± 4.2 vs 16.1 ± 3.7 vs 18.2 ± 5.1; P < 0.001), stroke volume (27.9 ± 29.6 vs 127.4 ± 112.6 vs 260.3 ± 151.8 mL; P < 0.001), and poor outcome (23.5 vs 77.3 vs 90.0%; P < 0.001). Cervical portion occlusion was characterized as rounded stump (82.4%) with calcification (52.9%) and fair LMC (94.1%); cavernous as spearhead occlusion (68.2%) with fair LMC (86.3%) and no calcification (95.5%); and terminus as streak-like occlusive pattern (60.0%) with poor LMC (60.0%), and no calcification (100%) on CTA.Our study indicates that acute ICA occlusion can be subtyped into cervical, cavernous, and terminus. Distinctive findings on initial CTA can help differentiate ICA-occlusion subtypes with specific characteristics.

Arterial Obstruction on Computed Tomographic or Magnetic Resonance Angiography and Response to Intravenous Thrombolytics in Ischemic Stroke

BACKGROUND AND PURPOSE

Computed tomographic angiography and magnetic resonance angiography are used increasingly to assess arterial patency in patients with ischemic stroke. We determined which baseline angiography features predict response to intravenous thrombolytics in ischemic stroke using randomized controlled trial data.

METHODS

We analyzed angiograms from the IST-3 (Third International Stroke Trial), an international, multicenter, prospective, randomized controlled trial of intravenous alteplase. Readers, masked to clinical, treatment, and outcome data, assessed prerandomization computed tomographic angiography and magnetic resonance angiography for presence, extent, location, and completeness of obstruction and collaterals. We compared angiography findings to 6-month functional outcome (Oxford Handicap Scale) and tested for interactions with alteplase, using ordinal regression in adjusted analyses. We also meta-analyzed all available angiography data from other randomized controlled trials of intravenous thrombolytics.

RESULTS

In IST-3, 300 patients had prerandomization angiography (computed tomographic angiography=271 and magnetic resonance angiography=29). On multivariable analysis, more extensive angiographic obstruction and poor collaterals independently predicted poor outcome (P<0.01). We identified no significant interaction between angiography findings and alteplase effect on Oxford Handicap Scale (P≥0.075) in IST-3. In meta-analysis (5 trials of alteplase or desmoteplase, including IST-3, n=591), there was a significantly increased benefit of thrombolytics on outcome (odds ratio>1 indicates benefit) in patients with (odds ratio, 2.07; 95% confidence interval, 1.18-3.64; P=0.011) versus without (odds ratio, 0.88; 95% confidence interval, 0.58-1.35; P=0.566) arterial obstruction (P for interaction 0.017).

CONCLUSIONS

Intravenous thrombolytics provide benefit to stroke patients with computed tomographic angiography or magnetic resonance angiography evidence of arterial obstruction, but the sample was underpowered to demonstrate significant treatment benefit or harm among patients with apparently patent arteries.

CLINICAL TRIAL REGISTRATION

URL: http://www.isrctn.com. Unique identifier: ISRCTN25765518.