Safety and Outcomes of Intravenous tPA in Acute Ischemic Stroke Patients With Prior Stroke Within 3 Months: Findings From Get With The Guidelines-Stroke

Velvet antler polypeptide (VAP) protects against cerebral ischemic injury through NF-κB signaling pathway in vitro

OBJECTIVE

Velvet antler polypeptide (VAP) has been shown to play important roles in the immune and nervous systems. The purpose of this study was to investigate the protective effects of VAP on cerebral ischemic injury with the involvement of NF-κB signaling pathway in vitro.

MATERIALS AND METHODS

PC-12 cells stimulated by oxygen-glucose deprivation/reperfusion (OGD/R) was used to mimic cerebral ischemic injury in vitro. The levels of ROS, SOD, and intracellular concentrations of Ca2+ were measured by the relevant kits. Meanwhile, the expressions of inflammatory cytokines (IL-6, IL-1β, and TNF-α) were determined by ELISA kit assay. In addition, MTT, EdU, and flow cytometry assays were used to measure the cell proliferation and apoptosis. Besides which, the related proteins of NF-κB signaling pathway were measured by western blotting assay.

RESULTS

VAP alleviated cerebral ischemic injury by reducing OGD/R-induced oxidative stress, inflammation, and apoptosis in PC-12 cells in a time dependent manner. Mechanistically, VAP inhibited the levels of p-p65 and p-IkB-α in a time dependent manner, which was induced by OGD/R operation. Moreover, NF-κB agonist diprovocim overturned the suppression effects of VAP on OGD/R-induced oxidative stress, inflammation, and apoptosis in PC-12 cells.

CONCLUSIONS

The results demonstrate that VAP may alleviate cerebral ischemic injury by suppressing the activation of NF-κB signaling pathway.

Innovations in Breaking Barriers: Liposomes as Near-Perfect Drug Carriers in Ischemic Stroke Therapy

Liposomes, noted for their tunable particle size, surface customization, and varied drug delivery capacities, are increasingly acknowledged in therapeutic applications. These vesicles exhibit surface flexibility, enabling the incorporation of targeting moieties or peptides to achieve specific targeting and avoid lysosomal entrapment. Internally, their adaptable architecture permits the inclusion of a broad spectrum of drugs, contingent on their solubility characteristics. This study thoroughly reviews liposome fabrication, surface modifications, and drug release mechanisms post-systemic administration, with a particular emphasis on drugs crossing the blood-brain barrier (BBB) to address lesions. Additionally, the review delves into recent developments in the use of liposomes in ischemic stroke models, offering a comparative evaluation with other nanocarriers like exosomes and nano-micelles, thereby facilitating their clinical advancement.

Quality Improvement in Neurocritical Care: a Review of the Current Landscape and Best Practices

Purpose of Review

The field of neurocritical care (NCC) has grown such that there is now a substantial body of literature on quality improvement specific to NCC. This review will discuss the development of this literature over time and highlight current best practices with practical tips for providers.

Recent Findings

There is tremendous variability in patient care models for NCC patients, despite evidence showing that certain structural elements are associated with better outcomes. There now also exist evidence-based recommendations for neurocritical care unit (NCCU) structure and processes, as well as NCC-specific performance measure (PM) sets; however, awareness of these is variable among care providers. The evidence-based literature on NCC structure, staffing, training, standardized order sets and bundles, transitions of care including handoff, prevention of bounce backs, bed flow optimization, and inter-hospital transfers is growing and offers many examples of successful performance improvement initiatives in NCCUs.

Summary

NCC providers care for patients with life-threatening conditions like intracerebral and subarachnoid hemorrhages, ischemic stroke, and traumatic brain injury, which are associated with high morbidity, complexity of treatment, and cost. Quality improvement initiatives have been successful in improving many aspects of NCC patient care, and NCC providers should continue to update and standardize their practices with consideration of this data. More research is needed to continue to identify high-risk and high-cost NCCU structures and processes and strategies to optimize them, validate current NCC PMs, and encourage clinical adoption of those that prove to be associated with improved outcomes.

Analysis of Mortality in Intracerebral Hemorrhage Patients with Hyperacute Ischemic Stroke Treated Using Thrombolytic Therapy: A Nationwide Population-based Cohort Study in South Korea

This study investigated the impact of intracerebral hemorrhage (ICH) on the cumulative mortality of patients with hyperacute ischemic stroke. This population-based retrospective cohort study used claims data from the National Health Insurance Service customized database of South Korea. The recruitment period was 2005−2018. The study population included patients with hyperacute ischemic stroke who had received intravenous thrombolysis. The primary endpoint was 12-month cumulative mortality, which was analyzed in both the ICH and no-ICH groups. Of the 50,550 patients included, 2567 (5.1%) and 47,983 (94.9%) belonged to the ICH and no-ICH groups, respectively. In the univariable analysis for 12-month mortality, ICH patients were substantially more prevalent among dead patients than among patients who survived (11.6% versus 3.6%; p < 0.001). The overall 12-month cumulative mortality rate was 18.8%. Mortality in the ICH group was higher than that in the no-ICH group (42.8% versus 17.5%; p < 0.001). In the multivariable analysis, the risk of 12-month cumulative mortality was 2.97 times higher in the ICH group than in the no-ICH group (95% confidence interval, 2.79−3.16). The risk of 12-month cumulative mortality in hyperacute ischemic stroke can increase approximately threefold after the occurrence of spontaneous ICH following intravenous thrombolysis.

Reasons and predictors of non-thrombolysis in patients with acute ischemic stroke admitted within 4.5 h

Objectives

Thrombolytic treatment in acute ischemic stroke (AIS) reduces stroke‐related disability. Nearly 40% of all patients with AIS (<4.5 h) receive thrombolysis, but there is a large variation in the use between hospitals. Little is known about reasons and predictors for not giving thrombolytic treatment. Therefore, we aimed to investigate reasons for non‐thrombolysis in patients admitted within 4.5 h.

Methods

All patients with AIS (<4.5 h) admitted to Akershus University Hospital, Norway, between January 2015 and December 2017 were examined. Patient characteristics and reasons for not giving thrombolysis were registered. Descriptive statistics and logistic regression analyses were performed.

Results

Of 535 patients admitted with AIS (<4.5 h), 250 (47%) did not receive thrombolysis and of these only 26% had an absolute contraindication to treatment. Among the 74% with relative contraindications, the most common reasons given were mild and improving symptoms. Previous stroke (OR 3.32, 95%CI 1.99–5.52), arriving between 3 h and 4.5 h after onset (OR 7.76, 95%CI 3.73–16.11) or having mild symptoms (OR 2.33, 95%CI 1.56–3.49) were all significant predictors of not receiving thrombolytic treatment in the multivariable logistic regression model.

Conclusion

A large proportion of patients with AIS do not receive thrombolysis. This study highlights up‐to‐date findings that arriving late in the time window, mild symptoms, and previous stroke are strong predictors of non‐treatment. It is uncertain whether there is an underuse of thrombolysis in AIS. Increasing the utility of thrombolysis in the 4.5 h time window must be weighed against possible harms.

Clinical Outcomes and Costs of Recurrent Ischemic Stroke: A Systematic Review

OBJECTIVE

Recurrent stroke patients suffer significant morbidity and mortality, representing almost 30% of the stroke population. Our objective was to determine the clinical outcomes and costs of recurrent ischemic stroke (recurrent-IS).

METHODS

Our study protocol was registered with the International Prospective Register of Systematic Reviews (CRD42020192709). Following PRISMA guidelines, our medical librarian conducted a search in EMBASE, PubMed, Web-of-Science, Scopus, and CINAHL (last performed on August 25, 2020).

INCLUSION CRITERIA

(1) Studies reporting clinical outcomes and/or costs of recurrent-IS; (2) Original research published in English in year 2010 or later; (3) Study participants aged ≥18 years.

EXCLUSION CRITERIA

(1) Case reports/studies, abstracts/posters, Editorial letters/reviews; (2) Studies analyzing interventions other than intravenous thrombolysis and thrombectomy. Four independent reviewers selected studies with review of titles/abstracts and full-text, and performed data extraction. Discrepancies were resolved by a senior independent arbitrator. Risk-of-bias was assessed using the Mixed Methods Appraisal Tool.

RESULTS

Initial search yielded 20,428 studies. Based on inclusion/exclusion criteria, 9 studies were selected, consisting of 24,499 recurrent-IS patients. In 5 studies, recurrent-IS ranged from 4.4-56.8% of the ischemic stroke cohorts at 3 or 12 months, or undefined follow-up. Mean age was 60-80 years and female proportions were 38.5-61.1%. Clinical outcomes included mortality 11.6-25.9% for in-hospital, 30-days, or 4-years (3 studies). In one study from the U.S., mean in-hospital costs were $17,121(SD-$53,693) and 1-year disability costs were $34,639(SD-$76,586) per patient.

CONCLUSIONS

Our study highlights the paucity of data on clinical outcomes and costs of recurrent-IS and identifies gaps in existing literature to direct future research.

Intravenous thrombolysis for acute ischemic stroke: why not?

PURPOSE OF REVIEW

The aim of this study was to summarize available evidence regarding the safety and efficacy of intravenous thrombolysis (IVT) using recombinant tissue-plasminogen activator (rt-PA) in acute ischemic stroke (AIS) patients with specific comorbidities and potential contraindications to systemic reperfusion therapy. Recent advances in IVT implementation in wake-up stroke and in extended time window using advanced neuroimaging will also be highlighted.

RECENT FINDINGS

Despite theoretical concerns of a higher bleeding risk with IVT, there are no data showing increased risk of symptomatic intracerebral haemorrhage (sICH) in patients with stroke mimics, including seizures, increasing age and dual antiplatelet pretreatment. In addition, recent randomized evidence allows us to expand the time window of IVT for AIS using advanced neuroimaging both in wake-up stroke patients and in patients presenting within 4.5-9 h from symptom onset fulfilling certain neuroimaging criteria (based on DWI/FLAIR mismatch or perfusion mismatch).

SUMMARY

IVT is a highly effective systemic reperfusion therapy that counts 25 years of everyday clinical experience but still presents several challenges in its application. Appropriate patient selection and adherence to rt-PA protocol is paramount in terms of safety. The effort to simplify the indications, expand the therapeutic time window and eliminate specific initial contraindications is continuously evolving.

Off-label use of intravenous thrombolysis for acute ischemic stroke: a critical appraisal of randomized and real-world evidence

Intravenous thrombolysis (IVT) represents the only systemic reperfusion therapy able to reverse neurological deficit in patients with acute ischemic stroke (AIS). Despite its effectiveness in patients with or without large vessel occlusion, it can be offered only to a minority of them, because of the short therapeutic window and additional contraindications derived from stringent but arbitrary inclusion and exclusion criteria used in landmark randomized controlled clinical trials. Many absolute or relative contraindications lead to disparities between the official drug label and guidelines or expert recommendations. Based on recent advances in neuroimaging and evidence from cohort studies, off-label use of IVT is increasingly incorporated into the daily practice of many stroke centers. They relate to extension of therapeutic time windows, and expansion of indications in co-existing conditions originally listed in exclusion criteria, such as use of alternative thrombolytic agents, pre-treatment with antiplatelets, anticoagulants or low molecular weight heparins. In this narrative review, we summarize recent randomized and real-world data on the safety and efficacy of off-label use of IVT for AIS. We also make some practical recommendations to stroke physicians regarding the off-label use of thrombolytic agents in complex and uncommon presentations of AIS or other conditions mimicking acute cerebral ischemia. Finally, we provide guidance on the risks and benefits of IVT in numerous AIS subgroups, where equipoise exists and guidelines and treatment practices vary.

Isoquercetin Improves Inflammatory Response in Rats Following Ischemic Stroke

Inflammatory response contributes to brain injury after ischemia and reperfusion (I/R). Our previous literature has shown isoquercetin plays an important role in protecting against cerebral I/R injury. The present study was conducted to further investigate the effect of isoquercetin on inflammation-induced neuronal injury in I/R rats with the involvement of cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) and inhibitor of NF-κB (I-κB)/nuclear factor-kappa B (NF-κB) signaling pathway mediated by Toll-like receptor 4 (TLR4) and C5a receptor 1 (C5aR1). In vivo middle cerebral artery occlusion and reperfusion (MCAO/R) rat model and in vitro oxygen-glucose deprivation and reperfusion (OGD/R) neuron model were used. MCAO/R induced neurological deficits, cell apoptosis, and release of cytokines such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 in ischemic brain in rats. Simultaneously, the expression of TLR4 and C5aR1 was significantly up-regulated in both MCAO/R rats and OGD/R neurons, accompanied with the inhibition of cAMP/PKA signaling and activation of I-κB/NF-κB signaling in the cortex of MCAO/R rats. Over-expression of C5aR1 in neurons induced decrease of cell viability, exerting similar effects with OGD/R injury. Isoquercetin acted as a neuroprotective agent against I/R brain injury to suppress inflammatory response and improve cell recovery by inhibiting TLR4 and C5aR1 expression, promoting cAMP/PKA activation, and inhibiting I-κB/NF-κB activation and Caspase 3 expression. TLR4 and C5aR1 contributed to inflammation and apoptosis via activating cAMP/PKA/I-κB/NF-κB signaling during cerebral I/R, suggesting that this signaling pathway may be a potent therapeutic target in ischemic stroke. Isoquercetin was identified as a neuroprotective agent, which maybe a promising therapeutic agent used for the treatment of ischemic stroke and related diseases.

Off-label intravenous thrombolysis for early recurrent brain embolism associated with aortic arch thrombus

Safety data of intravenous thrombolysis (IVT) in presence of aortic arch thrombus is scant. Furthermore, IVT is debatable in patients with prior recent stroke. We present a 51-year-old woman with recurrent major infarction 5 days after a minor left MCA territory stroke. She had a floating aortic arch thrombus and she was treated safely and effectively with off-label IVT. Patients with small infarct volumes and mild/no residual neurological deficits after an initial stroke might be considered for IVT in case of early recurrence. IVT may be reasonable in a context of acute severely disabling stroke associated with aortic arch thrombus.

Hyperacute Management of Ischemic Strokes: JACC Focus Seminar

Acute ischemic stroke is the leading cause of disability and among the leading causes of mortality worldwide. Intravenous tissue plasminogen activator has been a cornerstone for treatment of acute ischemic stroke for more than 20 years; however, its use is limited due to a narrow therapeutic window, several contraindications, and low efficacy to recanalize the artery in large vessel occlusion. Recently, the addition of endovascular mechanical thrombectomy of large artery occlusion has revolutionized the stroke treatment for most disabling strokes. The paper reviews updates to the thrombolytic treatment as well as catheter-based treatment, and results from recent trials in the selection of patients in an extended time window using perfusion imaging.