Risultati per: Stroke

Stroke, Ahead of Print. Right-to-left shunt, mainly due to patent foramen ovale (PFO), is likely responsible for ≈5% of all ischemic strokes and 10% of those occurring in young and middle-aged adults. Randomized clinical trials demonstrated that, in selected young and middle-aged patients with otherwise cryptogenic acute ischemic stroke and high-risk PFO, percutaneous PFO closure is more effective than antiplatelet therapy alone in preventing recurrence. However, PFO is generally a benign finding and is present in about one-quarter of the population. Therefore, in clinical practice, identifying PFOs that are likely to be pathogenetic is crucial for selecting suitable patients for PFO closure to prevent recurrent stroke and to avoid potentially harmful and costly overtreatment. Contrast transthoracic echocardiography has a relatively low sensitivity in detecting PFO, whereas transesophageal echocardiography is currently considered the gold standard for PFO detection. However, it is a relatively invasive procedure and may not always be easily feasible in the subacute setting. Contrast transcranial Doppler is a noninvasive, inexpensive, accurate tool for the detection of right-to-left shunt. We conducted a literature review on the use of contrast transcranial Doppler to detect and grade right-to-left shunt after an acute ischemic stroke and present a clinical workflow proposal for young and middle-aged patients.

Introduction
Persons after stroke experience limitations in activities of daily living even in the chronic phase. Many patients who had a stroke report mobility limitations with loss of social roles such as reduced gait-related participation. International best-practice recommendations for patients who had a stroke include interprofessional diagnostics as a core element for goal setting and intervention planning to improve social participation. Interprofessional diagnostics has not yet been implemented in Germany.

Methods and analysis
The aim is to develop an interprofessional diagnostic toolkit. This will be done in a multi-step process: first, an integrative review is conducted to synthesise the literature. Second, the experiences regarding diagnostics and walking outside is captured in focus groups with persons after stroke, relatives and health professionals. Third, a toolkit for the interprofessional diagnostic process of gait-related-participation will be developed based on the results of the previous steps in a future workshop. Fourth, the results of each work package will be integrated into the iterative development process for evaluation and implementation. All steps will be performed in accordance with the respective reporting guidelines.

Ethics and dissemination
This study has been approved by the ethics committee at the Ludwig Maximilians University (LMU), Germany and is overseen by LMU-Medical Institutional Review Board. Written informed consent will be obtained from all participants. Results will be disseminated through knowledge exchange with stakeholders and in peer-reviewed journal publications, scientific conferences, formal and informal reports. Stakeholders, patients and providers will be involved in most steps of the development from the beginning, which will facilitate later implementation at a larger scale.

Trial registration number
German Register Clinical Trials/Deutsches Register Klinischer Studien DRKS00032389.

Stroke, Ahead of Print. While imaging has traditionally played a fundamental role in the selection of patients undergoing endovascular thrombectomy, recent thrombectomy trials involving patients with large ischemic strokes demonstrated a consistent benefit of endovascular thrombectomy across all imaging strata, suggesting that reperfusion benefit may exist independent of current imaging constructs. Although these findings attest to the uniformly beneficial effects of reperfusion, they also shed doubt on the accuracy and utility of our imaging modalities in defining reversible versus irreversible ischemia and challenge the premise of imaging-based selection. We aimed to review the histopathologic studies and clinical trials that have shaped our understanding of current imaging constructs aiming to outline the existing imaging-neuropathological gap that may be far wider than previously perceived.

Stroke, Ahead of Print. BACKGROUND:Functional activation of the focal ischemic brain has been reported to improve outcomes by augmenting collateral blood flow. However, functional activation also increases metabolic demand and might thereby worsen outcomes. Indeed, preclinical and clinical reports have been conflicting. Here, we tested the effect of functional activation during acute ischemic stroke using distal middle cerebral artery occlusion in anesthetized mice.METHODS:Using transgenic mice expressing channelrhodopsin-2 in neurons, we delivered functional activation using physiological levels of transcranial optogenetic stimulation of the moderately ischemic cortex (ie, penumbra), identified using real-time full-field laser speckle perfusion imaging during a 1-hour distal microvascular clip of the middle cerebral artery. Neuronal activation was confirmed using evoked field potentials, and infarct volumes were measured in tissue slices 48 hours later.RESULTS:Optogenetic stimulation of the penumbra was associated with more than 2-fold larger infarcts than stimulation of the contralateral homotopic region and the sham stimulation group (n=10, 7, and 9; 11.0±5.6 versus 5.1±4.3 versus 4.1±3.7 mm3;P=0.008, 1-way ANOVA). Identical stimulation in wild-type mice that do not express channelrhodopsin-2 did not have an effect. Optogenetic stimulation was associated with a small increase in penumbral perfusion that did not explain enlarged infarcts.CONCLUSIONS:Our data suggest that increased neuronal activity during acute focal arterial occlusions can be detrimental, presumably due to increased metabolic demand, and may have implications for the clinical management of hyperacute stroke patients.

Stroke, Ahead of Print.

Circulation, Ahead of Print. BACKGROUND:Disparities in time to hospital presentation and prehospital stroke care may be important drivers in inequities in acute stroke treatment rates, functional outcomes, and mortality. It is unknown how patient-level factors, such as race and ethnicity and county-level socioeconomic status, affect these aspects of prehospital stroke care.METHODS:Cross-sectional study of patients with ischemic stroke, intracerebral hemorrhage, and subarachnoid hemorrhage in the Get With the Guidelines-Stroke registry, presenting from July 2015 to December 2019, with symptom onset

Stroke, Ahead of Print. BACKGROUND:Existing data suggested a rural-urban disparity in thrombolytic utilization for ischemic stroke. Here, we examined the use of guideline-recommended stroke care and outcomes in rural hospitals to identify targets for improvement.METHODS:This retrospective cohort study included patients (aged ≥18 years) treated for acute ischemic stroke at Get With The Guidelines-Stroke hospitals from 2017 to 2019. Multivariable mixed-effect logistic regression was used to compare thrombolysis rates, speed of treatment, secondary stroke prevention metrics, and outcomes after adjusting for patient- and hospital-level characteristics and stroke severity.RESULTS:Among the 1 127 607 patients admitted to Get With The Guidelines-Stroke hospitals in 2017 to 2019, 692 839 patients met the inclusion criteria. Patients who presented within 4.5 hours were less likely to receive thrombolysis in rural stroke centers compared with urban stroke centers (31.7% versus 43.5%; adjusted odds ratio [aOR], 0.72 [95% CI, 0.68–0.76]) but exceeded rural nonstroke centers (22.1%; aOR, 1.26 [95% CI, 1.15–1.37]). Rural stroke centers were less likely than urban stroke centers to achieve door-to-needle times of ≤45 minutes (33% versus 44.7%; aOR, 0.86 [95% CI, 0.76–0.96]) but more likely than rural nonstroke centers (aOR, 1.24 [95% CI, 1.04–1.49]). For secondary stroke prevention metrics, rural stroke centers were comparable to urban stroke centers but exceeded rural nonstroke centers (aOR of 1.66, 1.94, 2.44, 1.5, and 1.72, for antithrombotics within 48 hours of admission, antithrombotics at discharge, anticoagulation for atrial fibrillation/flutter, statin treatment, and smoking cessation, respectively). In-hospital mortality was similar between rural and urban stroke centers (aOR, 1.11 [95% CI, 0.99–1.24]) or nonstroke centers (aOR, 1.00 [95% CI, 0.84–1.18]).CONCLUSIONS:Rural hospitals had lower thrombolysis utilization and slower treatment times than urban hospitals. Rural stroke centers provided comparable secondary stroke prevention treatment to urban stroke centers and exceeded rural nonstroke centers. These results reveal important opportunities and specific targets for rural health equity interventions.

Circulation, Ahead of Print. BACKGROUND:In the ARTESiA trial (Apixaban for the Reduction of Thromboembolism in Patients With Device-Detected Subclinical Atrial Fibrillation), apixaban, compared with aspirin, reduced stroke or systemic embolism in patients with device-detected subclinical atrial fibrillation (SCAF). Clinical guidelines recommend considering SCAF episode duration when deciding whether to prescribe oral anticoagulation for this population.METHODS:We performed a retrospective cohort study in ARTESiA. Using Cox regression adjusted for CHA2DS2-VASc score and treatment allocation (apixaban or aspirin), we assessed frequency of SCAF episodes and duration of the longest SCAF episode in the 6 months before randomization as predictors of stroke risk and of apixaban treatment effect.RESULTS:Among 3986 patients with complete baseline SCAF data, 703 (17.6%) had no SCAF episode ≥6 minutes in the 6 months before enrollment. Among 3283 patients (82.4%) with ≥1 episode of SCAF ≥6 minutes in the 6 months before enrollment, 2542 (77.4%) had up to 5 episodes, and 741 (22.6%) had ≥6 episodes. The longest episode lasted

New England Journal of Medicine, Volume 391, Issue 9, Page 810-820, September 5, 2024.

Stroke, Ahead of Print. Artificial intelligence (AI) large language models (LLMs) now produce human-like general text and images. LLMs’ ability to generate persuasive scientific essays that undergo evaluation under traditional peer review has not been systematically studied. To measure perceptions of quality and the nature of authorship, we conducted a competitive essay contest in 2024 with both human and AI participants. Human authors and 4 distinct LLMs generated essays on controversial topics in stroke care and outcomes research. A panel ofStrokeEditorial Board members (mostly vascular neurologists), blinded to author identity and with varying levels of AI expertise, rated the essays for quality, persuasiveness, best in topic, and author type. Among 34 submissions (22 human and 12 LLM) scored by 38 reviewers, human and AI essays received mostly similar ratings, though AI essays were rated higher for composition quality. Author type was accurately identified only 50% of the time, with prior LLM experience associated with improved accuracy. In multivariable analyses adjusted for author attributes and essay quality, only persuasiveness was independently associated with odds of a reviewer assigning AI as author type (adjusted odds ratio, 1.53 [95% CI, 1.09–2.16];P=0.01). In conclusion, a group of experienced editorial board members struggled to distinguish human versus AI authorship, with a bias against best in topic for essays judged to be AI generated. Scientific journals may benefit from educating reviewers on the types and uses of AI in scientific writing and developing thoughtful policies on the appropriate use of AI in authoring manuscripts.

Stroke, Ahead of Print. BACKGROUND:For several decades, it has been recognized that overactivation of the glutamate-gated N-methyl-D-aspartate receptors (NMDARs) and subsequent Ca2+toxicity play a critical role in ischemic brain injury. 24S-hydroxycholesterol (24S-HC) is a major cholesterol metabolite in the brain, which has been identified as a potent positive allosteric modulator of NMDAR in rat hippocampal neurons. We hypothesize that 24S-HC worsens ischemic brain injury via its potentiation of the NMDAR, and reducing the production of 24S-HC by targeting its synthetic enzyme CYP46A1 provides neuroprotection.METHODS:We tested this hypothesis using electrophysiological, pharmacological, and transgenic approaches and in vitro and in vivo cerebral ischemia models.RESULTS:Our data show that 24S-HC potentiates NMDAR activation in primary cultured mouse cortical neurons in a concentration-dependent manner. At 10 µmol/L, it dramatically increases the steady-state currents by 51% and slightly increases the peak currents by 20%. Furthermore, 24S-HC increases NMDA and oxygen-glucose deprivation–induced cortical neuronal injury. The increased neuronal injury is largely abolished by NMDAR channel blocker MK-801, suggesting an NMDAR-dependent mechanism. Pharmacological inhibition of CYP46A1 by voriconazole or gene knockout ofCyp46a1dramatically reduces ischemic brain injury.CONCLUSIONS:These results identify a new mechanism and signaling cascade that critically impacts stroke outcome: CYP46A1 → 24S-HC → NMDAR → ischemic brain injury. They offer proof of principle for further development of new strategies for stroke intervention by targeting CYP46A1 or its metabolite 24S-HC.

Annals of Internal Medicine, Volume 177, Issue 9, Page JC99, September 2024.

Annals of Internal Medicine, Ahead of Print.

Circulation, Volume 150, Issue 10, Page 806-815, September 3, 2024. Guidelines help to facilitate treatment decisions based on available evidence, and also to provide recommendations in areas of uncertainty. In this paper, we compare the recommendations for stroke workup and secondary prevention of ischemic stroke and transient ischemic attack of the American Heart Association (AHA)/American Stroke Association (ASA) with the European Stroke Organization (ESO) guidelines. The primary aim of this paper is to offer clinicians guidance by identifying areas where there is consensus and where consensus is lacking, in the absence or presence of high-level evidence. We compared AHA/ASA with the ESO guideline recommendations for 7 different topics related to diagnostic stroke workup and secondary prevention. We categorized the recommendations based on class and level of evidence to determine whether there were relevant differences in the ratings of evidence that the guidelines used for its recommendations. Finally, we summarized major topics of agreement and disagreement, while also prominent knowledge gaps were identified. In total, we found 63 ESO and 82 AHA/ASA recommendations, of which 38 were on the same subject. Most recommendations are largely similar, but not all are based on high-level evidence. For many recommendations, AHA/ASA and ESO assigned different levels of evidence. For the 10 recommendations withLevel Aevidence (high quality) in AHA/ASA, ESO only labeled 4 of these ashigh quality. There are many remaining issues with either no or insufficient evidence, and some topics that are not covered by both guidelines. Most ESO and AHA/ASA Guideline recommendations for stroke workup and secondary prevention were similar. However not all were based on high-level evidence and the appointed level of evidence often differed. Clinicians should not blindly follow all guideline recommendations; the accompanying level of evidence informs which recommendations are based on robust evidence. Topics with lower levels of evidence, or those with recommendations that disagree or are missing, may be an incentive for further clinical research.

Background
Stroke survivors are at a substantially higher risk for adverse vascular events driven partly by poorly controlled vascular risk factors. Mobile health interventions supported by task shifting strategies have been feasible to test in small pilot trials in low-income settings to promote vascular risk reduction after stroke. However, real-world success and timely implementation of such interventions remain challenging, necessitating research to bridge the know-do gap and expedite improvements in stroke management. The Phone-based Interventions under Nurse Guidance after Stroke (PINGS-II) is a nurse-led mHealth intervention for blood pressure control among stroke survivors, currently being assessed for efficacy in a hybrid clinical trial across 10 hospitals in Ghana compared with usual care. This protocol aims to assess implementation outcomes such as feasibility, appropriateness, acceptability, fidelity, cost and implementation facilitators and barriers of the PINGS-II intervention.

Methods and analysis
This study uses descriptive mixed methods. Qualitative data to be collected include in-depth interviews and FGDs with patients who had a stroke on the PINGS-II intervention, as well as key informant interviews with medical doctors and health policy actors (implementation context, barriers and facilitators). Data will be analysed by thematic analysis. Quantitative data sources include structured questionnaires for clinicians (feasibility, acceptability and appropriateness), and patients who had a stroke (fidelity and costs). Analysis will include summary statistics like means, medians, proportions and exploratory tests of association including 2 analysis.

Ethics and dissemination
Ethics approval was obtained from the Committee for Human Research Publication and Ethics at the Kwame Nkrumah University of Science and Technology, Kumasi, Ghana. Voluntary written informed consent will be obtained from all participants. All the rights of the participants and ethical principles guiding scientific research shall be adhered to. Findings from the study will be presented in scientific conferences and published in a peer-reviewed scientific journal. A dissemination meeting will be held with relevant agencies of the Ghana Ministry of Health, clinicians, patient group representatives, and non-governmental organisations.

Stroke, Volume 55, Issue 9, Page 2199-2199, September 1, 2024.