Detection, Diagnosis and Treatment of Acute Ischemic Stroke: Current and Future Perspectives

Using Adaptive Imaging Parameters to Improve PEGylated Ultrasmall Iron Oxide Nanoparticles-Enhanced Magnetic Resonance Angiography

The PEGylated ultrasmall iron oxide nanoparticles (PUSIONPs) exhibit longer blood residence time and better biodegradability than conventional gadolinium-based contrast agents (GBCAs), enabling prolonged acquisitions in contrast-enhanced magnetic resonance angiography (CE-MRA) applications. The image quality of CE-MRA is dependent on the contrast agent concentration and the parameters of the pulse sequences. Here, a closed-form mathematical model is demonstrated and validated to automatically optimize the concentration, echo time (TE), repetition time (TR) and flip angle (FA). The pharmacokinetic studies are performed to estimate the dynamic intravascular concentrations within 12 h postinjection, and the adaptive concentration-dependent sequence parameters are determined to achieve optimal signal enhancement during a prolonged measurement window. The presented model is tested on phantom and in vivo rat images acquired from a 3T scanner. Imaging results demonstrate excellent agreement between experimental measurements and theoretical predictions, and the adaptive sequence parameters obtain better signal enhancement than the fixed ones. The low-dose PUSIONPs (0.03 mmol kg-1 and 0.05 mmol kg-1) give a comparable signal intensity to the high-dose one (0.10 mmol kg-1) within 2 h postinjection. The presented mathematical model provides guidance for the optimization of the concentration and sequence parameters in PUSIONPs-enhanced MRA, and has great potential for further clinical translation.

Association Between Calculated Small Dense Low-Density Lipoprotein Cholesterol (sdLDL-C) and Soft Carotid Plaques on CT Angiogram of the Head and Neck

BACKGROUND

Cerebrovascular accident (CVA), also commonly known as stroke, is an acute condition characterized by jeopardized perfusion of the brain tissue. Atherosclerosis is a common converging point for the various risk factors for CVA. It is a chronic, evolving condition of the vessel wall characterized by peculiar lesions known as atheromas. Low-density lipoprotein cholesterol (LDL-C) has been one of the established and traditional risk factors for the development of plaques in atherosclerosis. Small dense LDL-C (sdLDL-C) is a subclass of LDL-C that is considered more atherogenic, and its role in atherosclerotic plaque formation has been very well established. Hence, in this study, we aimed to find the association between calculated sdLDL-C and atherosclerotic carotid plaque (including various plaque characteristics).

MATERIALS AND METHODS

This retrospective cross-sectional study was conducted at Sri Ramachandra Medical College and Research Institute between December 2022 and December 2023 after getting ethics approval from the Institutional Ethics Committee. Patients who underwent CT angiogram (312) were included in the study, and their lipid profile data were collected from the Laboratory Information System. Participants were divided into groups depending on the presence or absence of carotid plaque, the characteristics of the plaque, and the narrowing caused by the plaque. sdLDL-C was calculated using Sampson formula from the lipid parameters in these groups. Statistical analysis was done using SPSS Statistics version 16.0 (SPSS Inc. Released 2007. SPSS for Windows, Version 16.0. Chicago, SPSS Inc.). A p-value of <0.05 was considered significant.

RESULTS

sdLDL-C was significantly higher in the plaque group (37.25 ± 13.69 mg/dL) when compared to the group without plaques on CT angiogram (34.09 ± 11.64 mg/dL) (p<0.05), wherein the LDL-C wasn't significantly different between the two groups. sdLDL-C was also elevated in the soft plaque sub-group (39.46 ± 13.63 mg/dL) when compared to the calcific plaque sub-group (35.41 ± 13.05 mg/dL), which was statistically significant (p<0.05).

CONCLUSION

sdLDL-C is associated with atherosclerotic carotid plaques, especially the soft plaques on CT angiogram, which are considered to be vulnerable plaques. Thus, calculated sdLDL-C can be utilized as a cost-effective tool to assess plaque vulnerability and monitor hypolipidemic treatment in addition to LDL-C.

Systemic biomarker associated with poor outcome after futile reperfusion

BACKGROUND

Successful recanalization does not lead to complete tissue reperfusion in a considerable percentage of ischemic stroke patients. This study aimed to identify biomarkers associated with futile recanalization. Leukoaraiosis predicts poor outcomes of this phenomenon. Soluble tumour necrosis factor-like weak inducer of apoptosis (sTWEAK), which is associated with leukoaraiosis degrees, could be a potential biomarker.

METHODS

This study includes two cohorts of ischemic stroke patients in a multicentre retrospective observational study. Effective reperfusion, defined as a reduction of ≥8 points in the National Institutes of Health Stroke Scale (NIHSS) within the first 24 h, was used as a clinical marker of effective reperfusion.

RESULTS

In the first cohort study, female sex, age, and high NIHSS at admission (44.7% vs. 81.1%, 71.3 ± 13.7 vs. 81.1 ± 6.7; 16 [13, 21] vs. 23 [17, 28] respectively; p < .0001) were confirmed as predictors of futile recanalization. ROC curve analysis showed that leukocyte levels (sensitivity of 99%, specificity of 55%) and sTWEAK level (sensitivity of 92%, specificity of 88%) can discriminate between poor and good outcomes. Both biomarkers simultaneously are higher associated with outcome after effective reperfusion (OR: 2.17; CI 95% 1.63-4.19; p < .0001) than individually (leukocytes OR: 1.38; CI 95% 1.00-1.64, p = .042; sTWEAK OR: 1.00; C I95% 1.00-1.01, p = .019). These results were validated using a second cohort, where leukocytes and sTWEAK showed a sensitivity of 100% and specificity of 66.7% and 75% respectively.

CONCLUSIONS

Leukocyte and sTWEAK could be biomarkers of reperfusion failure and subsequent poor outcomes. Further studies will be necessary to explore its role in reperfusion processes.

Early Cardiac Evaluation, Abnormal Test Results, and Associations with Outcomes in Patients with Acute Brain Injury Admitted to a Neurocritical Care Unit

Background: to examine factors associated with cardiac evaluation and associations between cardiac test abnormalities and clinical outcomes in patients with acute brain injury (ABI) due to acute ischemic stroke (AIS), spontaneous subarachnoid hemorrhage (SAH), spontaneous intracerebral hemorrhage (sICH), and traumatic brain injury (TBI) requiring neurocritical care. Methods: In a cohort of patients ≥18 years, we examined the utilization of electrocardiography (ECG), beta-natriuretic peptide (BNP), cardiac troponin (cTnI), and transthoracic echocardiography (TTE). We investigated the association between cTnI, BNP, sex-adjusted prolonged QTc interval, low ejection fraction (EF < 40%), all-cause mortality, death by neurologic criteria (DNC), transition to comfort measures only (CMO), and hospital discharge to home using univariable and multivariable analysis (adjusted for age, sex, race/ethnicity, insurance carrier, pre-admission cardiac disorder, ABI type, admission Glasgow Coma Scale Score, mechanical ventilation, and intracranial pressure [ICP] monitoring). Results: The final sample comprised 11,822 patients: AIS (46.7%), sICH (18.5%), SAH (14.8%), and TBI (20.0%). A total of 63% (n = 7472) received cardiac workup, which increased over nine years (p < 0.001). A cardiac investigation was associated with increased age, male sex (aOR 1.16 [1.07, 1.27]), non-white ethnicity (aOR), non-commercial insurance (aOR 1.21 [1.09, 1.33]), pre-admission cardiac disorder (aOR 1.21 [1.09, 1.34]), mechanical ventilation (aOR1.78 [1.57, 2.02]) and ICP monitoring (aOR1.68 [1.49, 1.89]). Compared to AIS, sICH (aOR 0.25 [0.22, 0.29]), SAH (aOR 0.36 [0.30, 0.43]), and TBI (aOR 0.19 [0.17, 0.24]) patients were less likely to receive cardiac investigation. Patients with troponin 25th-50th quartile (aOR 1.65 [1.10-2.47]), troponin 50th-75th quartile (aOR 1.79 [1.22-2.63]), troponin >75th quartile (aOR 2.18 [1.49-3.17]), BNP 50th-75th quartile (aOR 2.86 [1.28-6.40]), BNP >75th quartile (aOR 4.54 [2.09-9.85]), prolonged QTc (aOR 3.41 [2.28; 5.30]), and EF < 40% (aOR 2.47 [1.07; 5.14]) were more likely to be DNC. Patients with troponin 50th-75th quartile (aOR 1.77 [1.14-2.73]), troponin >75th quartile (aOR 1.81 [1.18-2.78]), and prolonged QTc (aOR 1.71 [1.39; 2.12]) were more likely to be associated with a transition to CMO. Patients with prolonged QTc (aOR 0.66 [0.58; 0.76]) were less likely to be discharged home. Conclusions: This large, single-center study demonstrates low rates of cardiac evaluations in TBI, SAH, and sICH compared to AIS. However, there are strong associations between electrocardiography, biomarkers of cardiac injury and heart failure, and echocardiography findings on clinical outcomes in patients with ABI. Findings need validation in a multicenter cohort.

The Multifaceted Role of Cofilin in Neurodegeneration and Stroke: Insights into Pathogenesis and Targeting as a Therapy

This comprehensive review explores the complex role of cofilin, an actin-binding protein, across various neurodegenerative diseases (Alzheimer's, Parkinson's, schizophrenia, amyotrophic lateral sclerosis (ALS), Huntington's) and stroke. Cofilin is an essential protein in cytoskeletal dynamics, and any dysregulation could lead to potentially serious complications. Cofilin's involvement is underscored by its impact on pathological hallmarks like Aβ plaques and α-synuclein aggregates, triggering synaptic dysfunction, dendritic spine loss, and impaired neuronal plasticity, leading to cognitive decline. In Parkinson's disease, cofilin collaborates with α-synuclein, exacerbating neurotoxicity and impairing mitochondrial and axonal function. ALS and frontotemporal dementia showcase cofilin's association with genetic factors like C9ORF72, affecting actin dynamics and contributing to neurotoxicity. Huntington's disease brings cofilin into focus by impairing microglial migration and influencing synaptic plasticity through AMPA receptor regulation. Alzheimer's, Parkinson's, and schizophrenia exhibit 14-3-3 proteins in cofilin dysregulation as a shared pathological mechanism. In the case of stroke, cofilin takes center stage, mediating neurotoxicity and neuronal cell death. Notably, there is a potential overlap in the pathologies and involvement of cofilin in various diseases. In this context, referencing cofilin dysfunction could provide valuable insights into the common pathologies associated with the aforementioned conditions. Moreover, this review explores promising therapeutic interventions, including cofilin inhibitors and gene therapy, demonstrating efficacy in preclinical models. Challenges in inhibitor development, brain delivery, tissue/cell specificity, and long-term safety are acknowledged, emphasizing the need for precision drug therapy. The call to action involves collaborative research, biomarker identification, and advancing translational efforts. Cofilin emerges as a pivotal player, offering potential as a therapeutic target. However, unraveling its complexities requires concerted multidisciplinary efforts for nuanced and effective interventions across the intricate landscape of neurodegenerative diseases and stroke, presenting a hopeful avenue for improved patient care.

The budget impact of alteplase in the treatment of acute ischemic stroke in Egypt

Introduction

Stroke is the second leading cause of mortality worldwide. Five percent of all the disability-adjusted life years (DALYs) lost around the world are attributed to stroke. This study aimed to assess the economic burden of acute ischemic stroke (AIS) in Egypt and reveal the benefits of alteplase treatment by measuring the resource use and costs associated with this treatment compared to the standard of care and extrapolate the overall budget impact of alteplase to the local Egyptian setting over a 5-year time horizon from a societal perspective.

Methods

A budget impact model was developed to estimate the impact of adding alteplase to the current treatment of AIS patients within the Egyptian healthcare setting. The efficacy data for both arms of the model were sourced from a systematic review of the literature. Resource use and cost data were sourced from a retrospective study. Proportions of patients potentially eligible for treatment and the treatment time distributions were estimated from an analysis of the results of this retrospective data collection. A univariate sensitivity analysis was conducted to assess the robustness of the model results. The input parameters varied between plausible extremes based on a review of available evidence.

Results

The total annual costs with alteplase treatment [i.e., drug, symptomatic intracerebral hemorrhage (ICH) management, acute hospitalization, and post-hospitalization costs] for the targeted patients from a societal perspective were estimated to be less than the total annual costs without alteplase. This resulted in savings of approximately EGP 37.2 million ($ 1.2 million), EGP 14.2 million ($ 458.06), EGP -33.0 million ($ -1.06 million), EGP -54.0 million ($ -1.74 million), and EGP -89.8 million ($ -2.89 million) for each of the 5 years, respectively. In year 1, more than 2,787 patients (+30.1%) achieved an excellent outcome and <1,204 patients (-22.3%) had a poor outcome when treated with alteplase. The savings in acute hospitalization and post-hospitalization costs offset the increase in drug and ICH management costs in the alteplase group compared to treatment without alteplase. The total cumulative cost savings for alteplase in AIS patients were estimated at EGP -228,146,871 ($ -7,359,576) over 5 years.

Conclusion

The budget impact model estimates suggest that from a societal perspective, alteplase is likely to be a cost-saving option for the treatment of AIS in Egypt due to the treatment benefits, resulting in savings in acute hospitalization and annual post-hospitalization costs.

Application of digitization and visualization-based muscle strength measurement in ischemic stroke patients with motor dysfunction

Ischemic stroke stands as a prevalent neurological ailment, where a paucity of methodologies exists for the assessment of functional outcomes post-stroke. Our objective was the development of a WeChat applet for the evaluation of muscle strength and the subsequent evaluation of its validity in ischemic stroke patients experiencing motor dysfunction. The assessment encompassed Lovett and NIHSS, followed by muscle strength values (MSV) and muscle strength ratios (MSR). These metrics were then scrutinized in relation to NIHSS and Lovett, followed by examination of their interrelationships. We enrolled a cohort of 157 patients, with an average age of 65 years, consisting of 96 males and 61 females. Lovett scores in the range of 2-4 and NIHSS scores spanning from 0 to 3 were found to correspond to specific values of MSV and MSR, respectively. Upon conducting correlation analysis, we noted that both MSV and MSR exhibited significant positive correlations with Lovett scores and NIHSS. Remarkably, the correlation of MSR with Lovett scores or NIHSS surpassed that of MSV. The WeChat applet offers a means of digitization and visualization of muscle strength. It correlates well with Lovett score and NIHSS, especially MSR. This bears potential significance in guiding the rehabilitation of stroke patients.

Assessment Precision of CT Perfusion Imaging in the Detection of Acute Ischemic Stroke: A Systematic Review and Meta-Analysis

Stroke, a prevalent medical emergency, comprises ischemic and hemorrhagic subtypes, with acute ischemic stroke (AIS) being a predominant type. The application of computed tomography perfusion (CTP) imaging has gained prominence due to its rapidity and accessibility in stroke evaluation. This study systematically reviews and conducts a meta-analysis of existing literature to assess the diagnostic accuracy of CTP in detecting AIS and predicting hemorrhagic transformation (HT). Employing Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, an extensive search was conducted across electronic databases and relevant radiology journals. Studies conducted between 2007 and 2023 that fulfilled predetermined inclusion criteria underwent quality assessment using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS 2) tool. Cochrane diagnostic accuracy tools were used for data extraction. Thirteen studies involving a total of 1014 patients were included in the analysis. The diagnostic performance of CTP in predicting HT demonstrated high sensitivity (86.7%) and moderate specificity (77.8%), resulting in an overall accuracy of 79.1%. The negative predictive value (NPV) was notably high (92.9%), signifying its efficacy in excluding patients at risk of HT. The positive predictive value (PPV) was comparatively lower (60.3%), highlighting the need for clinical context when making thrombolysis decisions. The false positive rate was 16.2%, while the false negative rate was minimal (9.8%). Subgroup analysis underscored consistent sensitivity and specificity across diverse imaging metrics. The findings of this study emphasize the promising diagnostic accuracy of CTP imaging in predicting HT subsequent to AIS. This non-invasive technique can aid treatment decisions and patient management strategies. By effectively assessing perfusion status and offering predictive insights, CTP imaging improves stroke intervention choices, especially in identifying patients with a lower risk of HT.

An overview of hyperbaric oxygen preconditioning against ischemic stroke

Ischemic stroke (IS) has become the second leading cause of morbidity and mortality worldwide, and the prevention of IS should be given high priority. Recent studies have indicated that hyperbaric oxygen preconditioning (HBO-PC) may be a protective nonpharmacological method, but its underlying mechanisms remain poorly defined. This study comprehensively reviewed the pathophysiology of IS and revealed the underlying mechanism of HBO-PC in protection against IS. The preventive effects of HBO-PC against IS may include inducing antioxidant, anti-inflammation, and anti-apoptosis capacity; activating autophagy and immune responses; upregulating heat shock proteins, hypoxia-inducible factor-1, and erythropoietin; and exerting protective effects upon the blood-brain barrier. In addition, HBO-PC may be considered a safe and effective method to prevent IS in combination with stem cell therapy. Although the benefits of HBO-PC on IS have been widely observed in recent research, the implementation of this technique is still controversial due to regimen differences. Transferring the results to clinical application needs to be taken carefully, and screening for the optimal regimen would be a daunting task. In addition, whether we should prescribe an individualized preconditioning regimen to each stroke patient needs further exploration.