Etiologic diagnosis of ischemic stroke subtypes with plasma biomarkers

Plasma metabolites, systolic blood pressure, lifestyle, and stroke risk: A prospective cohort study

BACKGROUND

To estimate the associations of stroke risk with plasma metabolites, metabolic risk score (MRS), the combinations of MRS with hypertension or lifestyle, and lifestyle-related metabolic signature. To assess the improvement of the stroke risk prediction model through the incorporation of MRS.

METHODS

A total of 77,315 participants from the UK Biobank were included in this study. Xgboost and LASSO-Cox regression were used to select metabolites and construct MRS. Elastic net regression was utilized to construct the lifestyle-related metabolic signature. Multivariate Cox regression was used to estimate the associations between metabolites, MRS, the combinations of MRS with hypertension or lifestyle, lifestyle-related metabolic signature, and stroke risk.

RESULTS

We identified 48, 63, 39, and 4 metabolites associated with the risk of stroke, ischemic stroke (IS), subarachnoid hemorrhage (SAH), and intracerebral hemorrhage (ICH), respectively. High MRS significantly increased the risk of stroke (HR = 2.65 (95% confidence interval (CI): 2.09-3.35)), IS (HR = 2.45 (95% CI: 1.89-3.17)), ICH (HR = 2.74 (95% CI: 1.55-4.85)), and SAH (HR = 4.64 (95% CI: 2.25-9.56)). In the combination analyses, compared with normal systolic blood pressure (SBP) and low MRS, normal/high SBP, and high MRS significantly increased stroke risk (HR = 5.80 (95% CI: 2.75-12.27)/6.37 (95% CI: 3.22-12.62)). A favorable/unfavorable lifestyle and high MRS also significantly increased stroke risk (HR = 2.38 (95% CI: 1.73-3.28)/3.86 (95% CI: 2.63-5.67)) compared with a favorable lifestyle and low MRS. Incorporating MRS into the 15-year stroke and IS risk prediction model increased the areas under the curves (AUCs) from 0.746 to 0.766 and from 0.771 to 0.811, respectively. The metabolic signature was correlated with adherence to a healthy lifestyle (r = 0.414; P = 2.22e-16) and inversely associated with stroke risk (HR = 0.80 (95% CI: 0.73-0.86)).

CONCLUSIONS

Various metabolites and MRS were significantly associated with the risk of stroke, IS, ICH, and SAH. Individuals with a high MRS may face an elevated stroke risk among populations with high SBP or unhealthy lifestyle, even those with normal SBP or healthy lifestyle. MRS provided modest improvement to the stroke risk prediction model. The lifestyle-related metabolic signature could reduce 20% stroke risk.

MR-proANP levels in Acute ischemic stroke and clinical outcomes: a systematic review and meta-analysis

In patients with acute ischemic stroke, midregional proatrial natriuretic peptide (MR-proANP) has shown promise in preliminary studies for risk stratification. The objective of this study is to evaluate the prognostic utility of MR-proANP in AIS, focusing on its ability to predict 90-day functional outcomes, mortality rates, and the presence of atrial fibrillation (Afib). A comprehensive literature search was conducted using PubMed, Web of Science, and Scopus, following PRISMA guidelines. The search strategy employed a combination of keywords and index terms including "Acute Ischemic Stroke," "AIS," "Cerebral Infarction," "Atrial Fibrillation," "AFib," "stroke," "MR-proANP," "Mid-regional pro-atrial natriuretic peptide," and "proatrial natriuretic peptide." Inclusion criteria encompassed any study focusing on MR-proANP and ischemic stroke, published up to October 15, 2023. Primary end points were newly diagnosed Afib, 90-day Modified Rankin Scale (mRS) score, and 90-day mortality. Studies were described in narrative and tabular form. Risk of bias was assessed using the ROBINS-I tool. Pooled estimates for our key end points were generated using a random effects model where appropriate. MR-proANP levels were significantly elevated in newly diagnosed Afib patients compared to no Afib patients (mean difference (MD): 134.4 pmol/l; 95% confidence interval (CI): 119.45 to 149.35, P < 0.0001). Unfavorable functional outcomes, as measured by mRS scores of ≥ 3 at 90 days, were associated with higher levels of MR-proANP (MD: 93.87 pmol/; 95% CI: 76.66 to 111.09, P < 0.0001). Elevated MR-proANP levels were also strongly correlated with increased 90-day mortality rates (MD: 164.43 pmol/; CI: 95.94 to 232.92, P < 0.0001). MR-proANP was significantly associated with functional outcomes, 90-day mortality, and the newly diagnosed AF. The limited number of studies included calls for further large-scale research to confirm these findings and explore the potential for expedited diagnostic procedures and targeted interventions like anticoagulant therapy.

Impact of D-dimer on the outcomes of endovascular thrombectomy for acute ischemic stroke: A systematic review and meta-analysis

BACKGROUND

There has been growing data about the association between D-dimer levels and thrombectomy outcomes in acute ischemic stroke patients (AIS) with no cumulative evidence. This systematic review and meta-analysis aim to discuss and analyze the findings of the current studies to provide more robust evidence in this regard.

METHODS

A systematic search was conducted through PubMed, Web of Science, Embase, and Scopus to retrieve all relevant investigations. A meta-analysis was conducted, and the results were presented in odds ratio (ORs) for binary variables and ratio of means (ROM) for continuous variables, each accompanied by its respective 95% confidence intervals (CIs).

RESULTS

After searching and screening, 14 studies were included. The analysis showed that the low D-dimer group had significantly higher rates of favorable functional outcome (OR: 4.40; 95%CI: 2.65-7.30; p < 0.001, n = 3) and recanalization (OR: 4.13; 95%CI: 1.57-10.84; p = 0.004, n = 3) than the high one. The association between D-dimer levels and first-pass effect and re-occlusion risk was also demonstrated. Eventually, two studies also demonstrated a significant association between high D-dimer levels and deep venous thrombosis and symptomatic intracranial hemorrhage as post-thrombectomy complications.

CONCLUSION

Current evidence indicates a significant association between D-dimer levels and post-thrombectomy outcomes in AIS patients. However, current data are remarkably heterogeneous, and additional comparative investigations are needed.

The Untargeted Metabolomics Reveals Differences in Energy Metabolism in Patients with Different Subtypes of Ischemic Stroke

AIMS

Ischemic stroke (IS) is the most common subtype of stroke. The risk factors and pathogenesis of IS are complex and varied due to different subtypes. Therefore, we used metabolomics technology to investigate the biomarkers and potential pathophysiological mechanisms of different subtypes of IS.

METHODS

We included 126 IS patients and divided them into two groups based on the TOAST classification: large-artery atherosclerosis (LAA) group (n = 87) and small-vessel occlusion (SVO) group (n = 39). Plasma metabolomics analysis was performed using liquid chromatography-high-resolution mass spectrometry (LC-HRMS) to identify metabolic profiles in LAA and SVO subtype IS patients and to determine metabolic differences between patients with the two subtypes of IS.

RESULTS

We identified 26 differential metabolites between LAA and SVO subtype IS. A multiple prediction model based on the plasm metabolites had good predictive ability for IS subtyping (AUC = 0.822, accuracy = 77.8%), with 12,13-DHOME being the most important differential metabolite in the model. The differential metabolic pathways between the two subtypes of IS patients included tricarboxylic acid (TCA) cycle, alanine, aspartate and glutamate metabolism, and pyruvate metabolism, mainly focused on energy metabolism.

CONCLUSION

12,13-DHOME emerged as the primary discriminatory metabolite between LAA and SVO subtypes of IS. In LAA subtype IS patients, energy metabolism, encompassing pyruvate metabolism and the TCA cycle, exhibited lower activity levels when compared to patients with the SVO subtype IS. The utilization of targeted metabolomics holds the potential to improve diagnostic accuracy for distinguishing stroke subtypes.

The role of the D-dimer to fibrinogen ratio in the classification of cardioembolism and atherosclerotic stroke

BACKGROUND

The D-dimer-to-fibrinogen ratio (DFR) is a good indicator of thrombus activity in thrombotic diseases, but its clinical role in acute ischaemic stroke (AIS) patients with different etiologies has not been studied. We evaluated the diagnostic value of the DFR for different subtypes of AIS.

METHODS

We conducted a single-center retrospective study of 269 patients with AIS who were referred to our stroke center within 4.5 h from Jan 2017 to Oct 2019. Coagulation data including DFRs were compared among the different stroke subtypes, and a separate retrospective validation sample was utilized to evaluate the prediction efficiency of the DFR for subtype diagnosis.

RESULTS

A higher DFR was observed in patients with cardioembolism than in those with large artery atherosclerosis (LAA) (odds ratio (OR) per 0.1 increase of the DFR: 1.49 [1.01-2.18]) after we adjusted for vascular risk factors. The diagnostic value of the DFR for detecting cardioembolism (AUC = 0.722, 95 % CI = 0.623-0.820) exceeded that of isolated D-dimer or fibrinogen. The validation sample (n = 117) further supported the notion that a diagnosis of cardioembolism was more common in patients with a DFR > 0.11 (multivariable risk ratio = 3.11[1.33-7.31], P = 0.009).

CONCLUSION

High DFRs were associated with cardioembolism in patients with AIS. The utilization of DFR can be beneficial for distinguishing a cardiac embolic source from atherosclerotic stroke.

Serum Caspase-3 Levels as a Predictive Molecular Biomarker for Acute Ischemic Stroke

Caspases are key players in the apoptotic process and have been found to contribute to the pathogenesis of a variety of diseases, including neurological disorders such as ischemic stroke. This study aimed to investigate the serum levels of Caspase-3 in patients with acute ischemic stroke (AIS) and in control patients without ischemic events. Moreover, we explored any potential associations with the clinical outcomes of AIS. We enrolled 69 consecutive patients with clinical signs and symptoms of AIS in the presence of a negative CT scan who presented themselves at the Clinical Neurological Department from the Emergency Clinical Hospital of Galati within the first 24 h of symptom onset. The control group comprised 68 patients without cerebral ischemic pathologies. A comparison of the two groups showed significantly higher levels of caspase-3 at 24 and 48 h after hospital admission. No significant associations between caspase-3 levels and clinical features of AIS were seen. However, in a subgroup analysis conducted on patients with moderate/severe and severe stroke, lower levels of caspase-3 were associated with early mortality. Caspase-3 levels did not directly correlate with AIS severity or prognosis when considering all AIS patients. In patients with moderate to severe National Institute of Health Stroke Scale (NIHSS) scores, caspase-3 might be a prognostic indicator of early death. Further studies are required to confirm these results and further explore the mechanisms behind these findings.

Biomarkers to improve functional outcome prediction after ischemic stroke: Results from the SICFAIL, STRAWINSKI, and PREDICT studies

BACKGROUND AND AIMS

Acute ischemic stroke (AIS) outcome prognostication remains challenging despite available prognostic models. We investigated whether a biomarker panel improves the predictive performance of established prognostic scores.

METHODS

We investigated the improvement in discrimination, calibration, and overall performance by adding five biomarkers (procalcitonin, copeptin, cortisol, mid-regional pro-atrial natriuretic peptide (MR-proANP), and N-terminal pro-B-type natriuretic peptide (NT-proBNP)) to the Acute Stroke Registry and Analysis of Lausanne (ASTRAL) and age/NIHSS scores using data from two prospective cohort studies (SICFAIL, PREDICT) and one clinical trial (STRAWINSKI). Poor outcome was defined as mRS > 2 at 12 (SICFAIL, derivation dataset) or 3 months (PREDICT/STRAWINSKI, pooled external validation dataset).

RESULTS

Among 412 SICFAIL participants (median age 70 years, quartiles 59-78; 63% male; median NIHSS score 3, quartiles 1-5), 29% had a poor outcome. Area under the curve of the ASTRAL and age/NIHSS were 0.76 (95% CI 0.71-0.81) and 0.77 (95% CI 0.73-0.82), respectively. Copeptin (0.79, 95% CI 0.74-0.84), NT-proBNP (0.80, 95% CI 0.76-0.84), and MR-proANP (0.79, 95% CI 0.75-0.84) significantly improved ASTRAL score's discrimination, calibration, and overall performance. Copeptin improved age/NIHSS model's discrimination, copeptin, MR-proANP, and NT-proBNP improved its calibration and overall performance. In the validation dataset (450 patients, median age 73 years, quartiles 66-81; 54% men; median NIHSS score 8, quartiles 3-14), copeptin was independently associated with various definitions of poor outcome and also mortality. Copeptin did not increase model's discrimination but it did improve calibration and overall model performance.

DISCUSSION

Copeptin, NT-proBNP, and MR-proANP improved modest but consistently the predictive performance of established prognostic scores in patients with mild AIS. Copeptin was most consistently associated with poor outcome in patients with moderate to severe AIS, although its added prognostic value was less obvious.

Plasma D-Dimer Levels Can Provide Useful Diagnostic Information on Acute Vertebral Compression Fractures in Patients with Low Back Pain in the Emergency Room

BACKGROUND

Patients with acute vertebral compression fractures (aVCFs) are frequently transferred to an emergency department by ambulance. The most useful imaging modality is magnetic resonance imaging (MRI); however, which patients should be prioritized for MRI evaluation may be unclear. The aim of this study was to evaluate plasma D-dimer levels as a biomarker for aVCFs.

METHODS

This retrospective cohort study included patients with low back pain in the emergency department between November 2017 and October 2020. Patients with infections, patients with coagulation disorders, and patients without D-dimer level measurements were excluded. The presence of an aVCF was detected with MRI. Blood samples were collected for routine blood tests. The predictive factors for aVCFs were evaluated with univariate and multivariable logistic regression analyses.

RESULTS

Overall, 191 consecutive MRI evaluations were ordered. After exclusions, 101 patients were reviewed. Based on MRI, 65 (64.4%) patients were diagnosed with aVCF. The presence of aVCF was significantly correlated with age (odds ratio [OR] = 1.052, 95% confidence interval [CI] 1.018-1.191), an old vertebral compression fracture (OR = 3.290, 95% CI 1.342-8.075), hemoglobin (OR = 0.699, 95% CI 0.535-0.912), and D-dimer levels (OR = 1.829, 95% CI 1.260-2.656). Results from a multivariable logistic regression analysis showed that D-dimer levels (OR = 1.642, 95% CI 1.188-2.228) remained a significant risk factor for the presence of aVCFs after adjustment for potential confounders.

CONCLUSIONS

Plasma D-dimer levels can provide useful diagnostic information about whether an aVCF is present.

The Relationship between CT Angiography Collateral Score and Biochemical Parameters during Acute Ischemic Stroke Caused by Middle Cerebral Artery Infarct

Background/Objectives: Collateral development after AIS is important for prognosis and treatment. In this study, we aimed to investigate the relationship and correlation between biochemical parameters and CT angiography collateral score within the first 9 h and its effect on the neurological outcomes of patients with AIS due to MCA infarction. Methods: A total of 98 patients with MCA infarction were hospitalized for diagnosis and treatment after undergoing CT angiography within 9 h of suffering a stroke. Demographic data, admission biochemical parameters, hospitalization data, and discharge NIHSS scores were recorded. Souza's scoring system for collateral distribution was used to evaluate collaterals. Souza CS system and clinical disability comparison outcomes identified. Results: According to the Souza CS system, 13 patients were in the malignant profile category, and 85 patients were in the good profile category. The NIHSS value of patients with a malignant profile was 27, while the mean NIHSS value of patients with a good profile was 9. There was a statistically significant difference in uric acid, total cholesterol, triglyceride, HDL cholesterol, CRP, hsCRP, D-Dimer, troponin I, vitamin B12, fibrinogen, NSE, homocysteine, aPTT, and INR levels according to collateral distribution. Conclusions: This study demonstrates that biochemical parameters can influence the distribution of malignant and benign collaterals in AIS independent of age and gender.

Stroke Related Brain-Heart Crosstalk: Pathophysiology, Clinical Implications, and Underlying Mechanisms

The emergence of acute ischemic stroke (AIS) induced cardiovascular dysfunctions as a bidirectional interaction has gained paramount importance in understanding the intricate relationship between the brain and heart. Post AIS, the ensuing cardiovascular dysfunctions encompass a spectrum of complications, including heart attack, congestive heart failure, systolic or diastolic dysfunction, arrhythmias, electrocardiographic anomalies, hemodynamic instability, cardiac arrest, among others, all of which are correlated with adverse outcomes and mortality. Mounting evidence underscores the intimate crosstalk between the heart and the brain, facilitated by intricate physiological and neurohumoral complex networks. The primary pathophysiological mechanisms contributing to these severe cardiac complications involve the hypothalamic-pituitary-adrenal (HPA) axis, sympathetic and parasympathetic hyperactivity, immune and inflammatory responses, and gut dysbiosis, collectively shaping the stroke-related brain-heart axis. Ongoing research endeavors are concentrated on devising strategies to prevent AIS-induced cardiovascular dysfunctions. Notably, labetalol, nicardipine, and nitroprusside are recommended for hypertension control, while β-blockers are employed to avert chronic remodeling and address arrhythmias. However, despite these therapeutic interventions, therapeutic targets remain elusive, necessitating further investigations into this complex challenge. This review aims to delineate the state-of-the-art pathophysiological mechanisms in AIS through preclinical and clinical research, unraveling their intricate interplay within the brain-heart axis, and offering pragmatic suggestions for managing AIS-induced cardiovascular dysfunctions.

The thrombus proteome in stroke reveals a key role of the innate immune system and new insights associated with its etiology, severity, and prognosis

BACKGROUND

Nowadays little is known about the molecular profile of the occluding thrombus of patients with ischemic stroke.

OBJECTIVES

To analyze the proteomic profile of thrombi in patients who experienced an ischemic stroke in order to gain insights into disease pathogenesis.

METHODS

Thrombi from an exploratory cohort of patients who experienced a stroke were obtained by thrombectomy and analyzed by sequential window acquisition of all theoretical spectra-mass spectrometry. Unsupervised k-means clustering analysis was performed to stratify patients who experienced a stroke. The proteomic profile was associated with both the neurological function (National Institute of Health Stroke Scale [NIHSS]) and the cerebral involvement (Alberta Stroke Program Early CT Score [ASPECTS]) prior to thrombectomy and the clinical status of patients at 3 months using the modified Rankin Scale. In an independent cohort of 210 patients who experienced a stroke, the potential role of neutrophils in stroke severity was interrogated.

RESULTS

Proteomic analysis identified 580 proteins in thrombi, which were stratified into 4 groups: hemostasis, proteasome and neurological diseases, structural proteins, and innate immune system and neutrophils. The thrombus proteome identified 3 clusters of patients with distinctive severity, prognosis, and etiology of the stroke. A protein signature clearly distinguished atherothrombotic and cardioembolic strokes. Several proteins were significantly correlated with the severity of the stroke (NIHSS and ASPECTS). Functional proteomic analysis highlighted the prominent role of neutrophils in stroke severity. This was in line with the association of neutrophil activation markers and count with NIHSS, ASPECTS, and the modified Rankin Scale score 90 days after the event.

CONCLUSION

The use of sequential window acquisition of all theoretical spectra-mass spectrometry in thrombi from patients who experienced an ischemic stroke has provided new insights into pathways and players involved in its etiology, severity, and prognosis. The prominent role of the innate immune system identified might pave the way for the development of new biomarkers and therapeutic approaches in this disease.

Soluble C-type lectin-like receptor 2 in stroke (CLECSTRO) study: protocol of a multicentre, prospective cohort of a novel platelet activation marker in acute ischaemic stroke and transient ischaemic attack

INTRODUCTION

Soluble C-type lectin-like receptor 2 (sCLEC-2) is a new biomarker for platelet activation, which can be easily measured by usual blood collection. We conducted the CLECSTRO, a prospective, observational cohort study, to evaluate the clinical implications of sCLEC-2 in patients with acute ischaemic stroke (AIS) and transient ischaemic attack (TIA).

METHODS AND ANALYSIS

The participants are patients with AIS/TIA and control patients required for differentiation from AIS/TIA. The target population is 600, including the patients and controls, who would be recruited from eight stroke centres across Japan. The inclusion criteria are AIS within 24 hours of onset and a modified Rankin Scale (mRS) score of 0-2, TIA within 7 days of onset, and contemporary patients required for differentiation from AIS/TIA. Plasma sCLEC-2 will be measured by high-sensitive chemiluminescent enzyme immunoassay using residual blood samples from routine laboratory examinations at the first visit in all patients and 7 days later or at discharge in patients with AIS/TIA. The outcomes include plasma levels of sCLEC-2 in patients with AIS/TIA and controls, sCLEC-2/D-dimer ratio in non-cardioembolic and cardioembolic AIS/TIA, correlation of sCLEC-2 with recurrence or worsening of stroke, severity of stroke, infarct size, ABCD2 score in TIA and outcome (mRS) at 7 days and 3 months.

ETHICS AND DISSEMINATION

This study was approved by the Ethical Committee of the University of Yamanashi as the central ethical committee in agreement with the ethical committees of all collaborative stroke centres. Informed consent will be obtained by an opt-out form from the patients at each stroke centre according to the Ethical Guidelines for Medical and Biological Research Involving Human Subjects by the Japanese Ministry of Health, Labour and Welfare.

TRIAL REGISTRATION NUMBERS

NCT05579405, UMIN000048954.

Plasma Glial Fibrillary Acidic Protein and N-Terminal Pro B-Type Natriuretic Peptide: Potential Biomarkers to Differentiate Ischemic and Hemorrhagic Stroke

Acute stroke management is critically time-sensitive and challenging. Blood-based biomarkers that can differentiate acute ischemic stroke (IS) from hemorrhagic stroke (HS) can greatly facilitate triage and early management. Admission blood samples obtained within 6 h of stroke symptom onset were analyzed in a derivation/validation design. GFAP, N-FL, NT-proBNP, copeptin, neutrophils (%), NLR, and platelet counts were assessed in the derivation cohort. The informative markers and the derived cutoff values were evaluated in the validation cohort. GFAP > 703 pg/mL showed a PPV of 76.9% and NPV of 95.8% for differentiating HS from IS. Multiple logistic regression analysis showed that GFAP and NT-proBNP were independent variables associated with IS and HS differentiation. Furthermore, applying a combined cutoff (GFAP > 703 pg/mL and NT-proBNP ≤ 125 pg/mL) for HS detection increased the PPV in both the derivation and validation cohorts (93.3% and 100%, respectively). GFAP and NT-proBNP levels were validated as informative blood biomarkers in the differentiation of IS and HS and using a combination of GFAP and NT-proBNP is suggested as a feasible strategy to differentiate stroke subtypes in the hyperacute phase of stroke.

Anti-diabetic combination therapy with pioglitazone or glimepiride added to metformin on the AGE-RAGE axis: a randomized prospective study

Introduction

The ratio between advanced glycation end products (AGEs) and soluble form of receptor (s-RAGE) has been proposed as a risk marker for renal and cardiovascular diseases. The aim of this study was to evaluate in the diabetes condition the influence of two different oral anti-diabetic treatments on the AGE/s-RAGE ratio, during a 5-year observation period.

Methods

Seventy-three patients with type 2 diabetes mellitus were randomly assigned to a drug therapy with pioglitazone or glimepiride, combined to metformin. Each subject was evaluated at baseline and after 5 years of treatment.

Results

In both groups s-RAGE levels did not significantly vary, while the levels of AGE and AGE/s-RAGE were both significantly reduced, basal compared to 5-year values. Within pioglitazone group, as well within glimepiride group, significant variations (Δ, as difference between 5 years of treatment minus basal) were observed for AGE (Δ= -21.1±13.4 µg/ml, P<0.001 for pioglitazone; Δ= -14.4±11.4 µg/ml, P<0.001 for glimepiride) and in AGE/s-RAGE (Δ= -0.037±0.022 µg/pg, P<0.001 for pioglitazone; Δ= -0.024±0.020µg/pg, P<0.001 for glimepiride), suggesting an average decrease of the parameters by more than 50% in both treatments. Pioglitazone was more effective than glimepiride in reducing AGE/s-RAGE ratio after 5 years of therapy.

Conclusion

These data can help to explain the benefits of oral anti-diabetic therapy in relation to the reduction of cardiovascular risk, as suggested by variations in AGE/s-RAGE ratio as biochemical marker of endothelial function; in particular, treatment with pioglitazone seems to offer greater long-term benefit on AGE-RAGE axis.

Clinical significance of D-dimer levels during acute period in ischemic stroke

BACKGROUND

Initial D-dimer level is a well-known prognostic parameter in patients with acute ischemic stroke (AIS). However, there have been no studies on the clinical significance of follow-up D-dimer levels. In this study, we evaluated the association between initial and follow-up D-dimer levels and early neurological deterioration (END) in patients with AIS.

METHODS

We included consecutive patients with AIS who had a positive initial D-dimer test (> 0.55 mg/L) between March 2021 and November 2022. The follow-up D-dimer test was performed on the 7th day after hospitalization and on the day of discharge if discharged earlier. END was defined as an increase of ≥ 2 in the total NIHSS score, or ≥ 1 in the motor NIHSS score within the first 7 days of admission. As medical conditions closely associated with the initial and follow-up D-dimer levels in AIS patients, we also evaluated the history of cancer, active cancer, and venous thromboembolism (VTE) that occurred during hospitalization together.

RESULTS

A total of 246 patients with AIS were evaluated (median age: 87 years, male: 56.5%). In multivariable logistic regression analysis, the initial D-dimer level was closely associated with END after adjusting for confounders (adjusted odds ratio [aOR]: 1.48, 95% CI: 1.06-2.05). The follow-up D-dimer level also showed a close correlation with END (aOR: 1.60, 95% CI: 1.16-2.20). Regarding the analysis of the association between D-dimer levels and underlying cancer or VTE, the initial D-dimer level showed a statistically significant positive relationship only with active cancer (P = 0.024). On the other hand, the follow-up D-dimer level was found to be statistically significantly associated with a history of cancer (P = 0.024), active cancer (P = 0.001), and VTE (P = 0.001).

CONCLUSIONS

Initial and follow-up D-dimer levels were associated with END in AIS patients. Particularly, the follow-up D-dimer level showed a clear correlation not only with END but also with the underlying cancer or the occurrence of VTE during the acute period.

Molecular biomarkers predicting newly detected atrial fibrillation after ischaemic stroke or TIA: A systematic review

Background:

Several molecular biomarkers are available that predict newly detected atrial fibrillation (NDAF). We aimed to identify such biomarkers that predict NDAF after an Ischaemic stroke (IS)/Transient Ischaemic Attack (TIA) and evaluate their performance.

Methods:

A systematic review was undertaken in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Studies of patients with IS, TIA, or both, who underwent ECG monitoring for ⩾24 h, which reported molecular biomarkers and frequency of NDAF after electronic searches of multiple databases were included.

Results:

Twenty-one studies (76% IS, 24% IS and TIA) involving 4640 patients were included. Twelve biomarkers were identified, with cardiac biomarkers evaluated in the majority (75%) of patients. Performance measures were inconsistently reported. Among cohorts selecting high-risk individuals (12 studies), the most studied biomarkers were N-Terminal-Pro Brain Natriuretic Peptide (NT-ProBNP, five studies; C-statistics reported by three studies, 0.69–0.88) and Brain Natriuretic Peptide (BNP, two studies; C-statistics reported in two studies, 0.68–0.77). Among unselected cohorts (nine studies), the most studied biomarker was BNP (six studies; C-statistics reported in five studies, 0.75–0.88). Only BNP was externally validated (two studies) but using different thresholds to categorise risk of NDAF.

Conclusion:

Cardiac biomarkers appear to have modest to good discrimination for predicting NDAF, although most analyses were limited by small, heterogeneous study populations. Their clinical utility should be explored further, and this review supports the need to assess the role of molecular biomarkers in large prospective studies with standardised selection criteria, definition of clinically significant NDAF and laboratory assays.

Vertigo in Acute Stroke Is a Predictor of Brain Location but Is Not Related to Early Outcome: The Experience of Sagrat Cor Hospital of Barcelona Stroke Registry

BACKGROUND

Vertigo is an uncommon symptom among acute stroke victims. Knowledge about the clinical profile, the brain location, and the early outcome in stroke patients with cerebrovascular diseases and vertigo remains limited.

OBJECTIVES

In this study, the effects of vertigo on cerebral topography and early prognosis in cerebrovascular diseases were investigated.

METHODS

A comparative analysis in terms of demographics, risk factors, clinical characteristics, stroke subtypes, cerebral and vascular topography, and early outcome was performed between patients with presence or absence of vertigo on a sample of 3743 consecutive acute stroke patients available from a 24-year ongoing single-center hospital-based stroke registry.

RESULTS

Vertigo was present in 147 patients (3.9%). Multiple logistic regression analysis showed that variables independently associated with vertigo were: location in the cerebellum (OR 5.59, CI 95% 3.24-9.64), nausea or vomiting (OR 4.48, CI 95% 2.95-6.82), medulla (OR 2.87, CI 95% 1.31-6.30), pons (OR 2.39, CI 95% 1.26-4.51), basilar artery (OR 2.36, CI 95% 1.33-4.17), ataxia (OR 2.33, CI 95% 1.41-3.85), and headache (OR 2.31, CI 95% 1.53-3.49).

CONCLUSION

The study confirmed that the presence of vertigo was not related with increased in-hospital mortality or poor prognosis at hospital discharge. Vertigo is mainly related to non-lacunar vertebrobasilar stroke with topographic localization in the cerebellum and/or brainstem.

Role of cell-free DNA for predicting incidence and outcome of patients with ischemic stroke

Early diagnosis and prognosis of ischemic stroke remains a critical challenge in clinical settings. A blood biomarker can be a promising quantitative tool to represent the clinical manifestations in ischemic stroke. Cell-free DNA (cfDNA) has recently turned out to be a popular circulating biomarker due to its potential relevance for diagnostic applications in a variety of disorders. Despite bright outlook of cfDNA in clinical applications, very less is known about its origin, composition, or function. Several recent studies have identified cell-derived mitochondrial components including mitochondrial DNA (mtDNA) in the extracellular spaces including blood and cerebrospinal fluid. However, the time course of alterations in plasma mtDNA concentrations in patients after an ischemic stroke is poorly understood. DNA is thought to be freed into the plasma shortly after the commencement of an ischemic stroke and then gradually decreased. However, the importance of cell-free mtDNA (cf-mtDNA) in ischemic stroke is still unknown. This review summarizes about the utility of biomarkers which has been standardized in clinical settings and role of cfDNA including cf-mtDNA as a non-invasive potential biomarker of ischemic stroke.

Atrial cardiomyopathy markers and new-onset atrial fibrillation risk in patients with acute myocardial infarction

BACKGROUND

New-onset atrial fibrillation (NOAF) after acute myocardial infarction (AMI) is common and independently correlated with poor prognosis. The purpose of this study is to explore whether atrial cardiomyopathy (ACM) markers improve NOAF risk assessment and contribute to therapy decision-making to improve prognosis.

METHODS

We retrospectively analyzed 4713 patients with AMI without a documented history of atrial fibrillation (AF). We measured markers of ACM including P-wave terminal force in ECG lead V1 (PTFV1), Left atrial dimension (LAD), and B-type natriuretic peptide (BNP). Patients were stratified into tertiles of PTFV1, LAD, and BNP levels. Associations between markers and NOAF were evaluated using logistic regression analysis.

RESULTS

Overall, 222 (4.71%) patients had NOAF out of 4713 patients. The prevalence of NOAF increased gradually with PTFV1, LAD, and BNP tertiles. On multivariable regression analysis with potential confounders, elevated PTFV1, LAD, and BNP markers were significantly associated with an increased risk of NOAF. The addition of PTFV1, LAD, and BNP to the AF risk factors recommended by the 2020 ESC Guidelines significantly improved risk discrimination for NOAF.

CONCLUSION

Atrial cardiomyopathy markers including PTFV1, LAD, and BNP were strongly associated with NOAF after AMI. The prediction performance of the clinical model for NOAF was increased by the addition of these markers.

A systematic review and meta-analysis of abnormalities in hematological and biochemical markers among Bangladeshi COVID-19 cases

Background and Aims

Abnormalities in hematological and biochemical markers are assumed to be associated with the progression of COVID-19 disease. This meta-analysis was performed to assess the consequences of abnormalities of biomarkers (D-dimers, C-reactive protein [CRP], serum ferritin, lactate dehydrogenase [LDH], random blood sugar [RBS], absolute neutrophil count [ANC], neutrophil to lymphocyte ratio (NLR), serum creatinine, and hemoglobin) in the Bangladeshi COVID-19 patients.

Methods

The data of biomarker levels in Bangladeshi COVID-19 patients were gathered from five databases: PubMed, ScienceDirect, Web of Science, Google Scholar and Bangladesh Journals Online between January 2020 to March 2022. Review Manager 5.4 was used for the meta-analysis, and Egger's test and Begg-Mazumdar's rank correlation were used to investigate publication bias.

Results

This study included 1542 patients with 567 severe and 975 nonsevere statuses. Based on the accumulated data synthesis, there is a strong correlation between disease severity and different biomarkers, including D-dimer, CRP, ferritin, LDH, RBS, NLR, and serum creatinine (MD = 1.16, p = 0.0004; MD = 22.97, p = 0.003; MD = 419.26, p < 0.00001; MD = 118.37, p = 0.004; MD = 1.96, p = 0.02; MD = 1.26, p = 0.02; and MD = 0.31, p = 0.008, respectively). A significantly decreased correlation was observed for hemoglobin levels in severe COVID-19 patients (MD = -0.73, p = 0.10).

Conclusion

The elevated biomarkers level was noticed in severe cases compared to nonsevere patients, revealing that D-dimer, CRP, ferritin, LDH, RBS, NLR, and serum creatinine are significantly correlated to COVID-19 severity. Only lower hemoglobin level was found to be associated with COVID-19 severity.

Impact of Exercise on Cerebrovascular Physiology and Risk of Stroke

Ischemic heart disease and stroke are the number 1 and number 2 causes of death worldwide, respectively. A lifelong commitment to exercise reduces the risk of these adverse events and is also associated with several cardiometabolic improvements, including reductions in blood pressure, cholesterol, and inflammatory markers, as well as improved glucose control. Routine exercise also reduces the risk of developing comorbidities that increase the risk of cardiovascular or cerebrovascular disease. While the benefits of a lifelong commitment to exercise are well documented, there is a complex interaction between exercise and stroke risk, such that the risk of ischemic or hemorrhagic stroke may increase acutely during or immediately following exercise. In this article, we discuss the physiological responses to different types of exercise, as well as the determinants of resting and exertional cerebrovascular perfusion, and explore the complex interaction between atrial fibrillation, exercise, and stroke risk. Finally, we highlight the increased risk of stroke during different types of exercise, as well as factors that may alleviate this risk.

A novel biomarker panel index improves risk stratification after ischemic stroke

Background:

We investigated 92 blood biomarkers implicated in the pathophysiological pathways of ischemic injury, inflammation, hemostasis, and regulation of vascular resistance to predict post-stroke mortality.

Aim:

Based on the most promising markers, we aimed to create a novel Biomarker Panel Index (BPI) for risk stratification.

Methods:

In this prospective study, we measured 92 biomarkers in 320 stroke patients. The primary outcome measure was mortality within 90 days. We estimated the association of each biomarker using logistic regression adjusting for multiple testing. The most significant 16 biomarkers were used to create the BPI. We fitted regression models to estimate the association and the discriminatory accuracy of the BPI with mortality and stroke etiology.

Results:

Adjusted for demographic and vascular covariates, the BPI remained independently associated with mortality (odds ratio (OR) 1.68, 95% confidence interval (CI): 1.29–2.18) and cardioembolic stroke etiology (OR 1.38, 95% CI: 1.10–1.74), and improved the discriminatory accuracy to predict mortality (area under the receiver operating characteristic curve (AUC) 0.93, 95% CI: 0.89–0.96) and cardioembolic stroke etiology (AUC 0.70, 95% CI: 0.64–0.77) as compared to the best clinical prediction models alone (AUC 0.89, 95% CI: 0.84–0.94 and AUC 0.66, 95% CI: 0.60-0.73, respectively).

Conclusions:

We identified a novel BPI improving risk stratification for mortality after ischemic stroke beyond established demographic and vascular risk factors. Furthermore, the BPI is associated with underlying cardioembolic stroke etiology. These results need external validation.

The Potential Impact of Neuroimaging and Translational Research on the Clinical Management of Lacunar Stroke

Lacunar infarcts represent one of the most frequent subtypes of ischemic strokes and may represent the first recognizable manifestation of a progressive disease of the small perforating arteries, capillaries, and venules of the brain, defined as cerebral small vessel disease. The pathophysiological mechanisms leading to a perforating artery occlusion are multiple and still not completely defined, due to spatial resolution issues in neuroimaging, sparsity of pathological studies, and lack of valid experimental models. Recent advances in the endovascular treatment of large vessel occlusion may have diverted attention from the management of patients with small vessel occlusions, often excluded from clinical trials of acute therapy and secondary prevention. However, patients with a lacunar stroke benefit from early diagnosis, reperfusion therapy, and secondary prevention measures. In addition, there are new developments in the knowledge of this entity that suggest potential benefits of thrombolysis in an extended time window in selected patients, as well as novel therapeutic approaches targeting different pathophysiological mechanisms involved in small vessel disease. This review offers a comprehensive update in lacunar stroke pathophysiology and clinical perspective for managing lacunar strokes, in light of the latest insights from imaging and translational studies.

High D-dimer concentration is a significant independent prognostic factor in patients with acute large vessel occlusion undergoing endovascular thrombectomy

OBJECTIVE

This study aimed to investigate prognostic factors that affect modified Rankin Scale (mRS) score at 3 months after onset in acute stroke patients with large vessel occlusion (LVO) undergoing endovascular thrombectomy.

METHODS

We retrospectively examined 87 consecutive patients who underwent endovascular cerebral thrombectomy for acute anterior circulation LVO at Oita University Hospital and Nagatomi Neurosurgery Hospital from January 2014 to December 2020.

RESULTS

Age, National Institutes of Health Stroke Scale (NIHSS) score, and D-dimer concentration on admission were significant univariate prognostic factors related to mRS score 3 months after stroke onset. Multivariate logistic regression analysis showed that D-dimer concentration was the only significant independent prognostic factor. The area under the receiver operating characteristic curve for D-dimer concentration and mRS score at 3 months was 0.715 (95% confidence interval, 0.599 - 0.831); sensitivity and specificity were 60.6% and 80.0%, respectively, using a 1.9 μg/mL cutoff value.

CONCLUSIONS

Prognosis may be worse in patients undergoing acute endovascular cerebral thrombectomy with high D-dimer concentration on admission. Other treatment options should be considered for these patients.

Uncertainties and Controversies in the Management of Ischemic Stroke and Transient Ischemic Attack Patients With Patent Foramen Ovale

Multiple randomized clinical trials have demonstrated the benefit of patent foramen ovale closure over medical therapy alone for patients who have had a stroke that has been attributed to the patent foramen ovale. Nevertheless, there are many areas of uncertainty and controversy related to patient selection, pathophysiology, diagnosis, and treatment. We summarize the available data on these challenging topics and attempt to provide some clarity and future directions for clinicians and investigators.

Copeptin: a potential blood biomarker for acute ischemic stroke

Background

Copeptin is a new blood biomarker for acute ischemic stroke which emerged to assist clinicians with decision-making. Serum copeptin can accurately reflect vasopressin concentration, which plays a role in aggravation of inflammatory responses, ions and neurotransmitters dysfunctions. The objective of this work was to investigate the relation between copeptin level as a blood biomarker and the short-term prognosis of acute ischemic stroke after 3 months. The current study included 45 patients with first ever acute ischemic stroke and 45 healthy volunteers as a control. Clinical evaluation, CT and MRI of the brain, NIHSS on admission, and mRS after 3 months were done for the patients, and all the patients and control were subjected to assessment of serum level of copeptin by ELISA technique.

Results

Copeptin level was significantly higher in patients with acute ischemic stroke compared to healthy control subjects (p-value = 0.001). Also, copeptin level was significantly higher in patients with severe stroke (NIHSS > 16) than in those with mild-to-moderate stroke (NIHSS 0–15) at presentation and in patients with unfavorable outcome (mRS 3–6) when compared to patients with favorable outcome (mRS 0–2) (p-value = 0.003 and 0.001, respectively).

Copeptin level was significantly lower in patients who received thrombolytic therapy with rTPA (p-value = 0.049).

Conclusion

Copeptin has an interesting potential as a new prognostic biomarker for patients with acute ischemic stroke as its level was significantly higher in patients with severe stroke and in patients with unfavorable outcome.

A Novel Combination of Blood Biomarkers and Clinical Stroke Scales Facilitates Detection of Large Vessel Occlusion Ischemic Strokes

Acute ischemic stroke caused by large vessel occlusions (LVOs) is a major contributor to stroke deaths and disabilities; however, identification for emergency treatment is challenging. We recruited two separate cohorts of suspected stroke patients and screened a panel of blood-derived protein biomarkers for LVO detection. Diagnostic performance was estimated by using blood biomarkers in combination with NIHSS-derived stroke severity scales. Multivariable analysis demonstrated that D-dimer (OR 16, 95% CI 5–60; p-value < 0.001) and GFAP (OR 0.002, 95% CI 0–0.68; p-value < 0.05) comprised the optimal panel for LVO detection. Combinations of D-dimer and GFAP with a number of stroke severity scales increased the number of true positives, while reducing false positives due to hemorrhage, as compared to stroke scales alone (p-value < 0.001). A combination of the biomarkers with FAST-ED resulted in the highest accuracy at 95% (95% CI: 87–99%), with sensitivity of 91% (95% CI: 72–99%), and specificity of 96% (95% CI: 90–99%). Diagnostic accuracy was confirmed in an independent cohort, in which accuracy was again shown to be 95% (95% CI: 87–99%), with a sensitivity of 82% (95% CI: 57–96%), and specificity of 98% (95% CI: 92–100%). Accordingly, the combination of D-dimer and GFAP with stroke scales may provide a simple and highly accurate tool for identifying LVO patients, with a potential impact on time to treatment.

Scalable Bio Marker Combinations for Early Stroke Diagnosis: A Systematic Review

Background: Acute stroke treatment is a time-critical process in which every minute counts. Laboratory biomarkers are needed to aid clinical decisions in the diagnosis. Although imaging is critical for this process, these biomarkers may provide additional information to distinguish actual stroke from its mimics and monitor patient condition and the effect of potential neuroprotective strategies. For such biomarkers to be effectively scalable to public health in any economic setting, these must be cost-effective and non-invasive. We hypothesized that blood-based combinations (panels) of proteins might be the key to this approach and explored this possibility through a systematic review. Methods: We followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines for systematic review. Initially, the broader search for biomarkers for early stroke diagnosis yielded 704 hits, and five were added manually. We then narrowed the search to combinations (panels) of the protein markers obtained from the blood. Results: Twelve articles dealing with blood-based panels of protein biomarkers for stroke were included in the systematic review. We observed that NR2 peptide (antibody against the NR2 fragment) and glial fibrillary acidic protein (GFAP) are brain-specific markers related to stroke. Von Willebrand factor (vWF), matrix metalloproteinase 9 (MMP-9), and S100β have been widely used as biomarkers, whereas others such as the ischemia-modified albumin (IMA) index, antithrombin III (AT-III), and fibrinogen have not been evaluated in combination. We herein propose the following new combination of biomarkers for future validation: panel 1 (NR2 + GFAP + MMP-9 + vWF + S100β), panel 2 (NR2 + GFAP + MMP-9 + vWF + IMA index), and panel 3 (NR2 + GFAP + AT-III + fibrinogen). Conclusions: More research is needed to validate, identify, and introduce these panels of biomarkers into medical practice for stroke recurrence and diagnosis in a scalable manner. The evidence indicates that the most promising approach is to combine different blood-based proteins to provide diagnostic precision for health interventions. Through our systematic review, we suggest three novel biomarker panels based on the results in the literature and an interpretation based on stroke pathophysiology.

Cerebrovascular comorbidity, high blood levels of C-reactive protein and D-dimer are associated with disease outcomes in COVID-19 patients

The emerging coronavirus disease (COVID-19) swept the world, affecting more than 200 countries and territories. As of August 22, 2020, the pandemic infected more than 23,329,752 including 807,054 patients who have died. Although the main clinical features of the pandemic disease are respiratory, cerebrovascular comorbidities emerged as one of the leading causes of death associated with COVID-19. Different case reports have indicated that C-reactive protein (CRP) and D-dimer (pro-inflammatory biomarkers) were elevated in COVID-19 patients, which can significantly increase the risk of ischemic stroke. Available data on cerebrovascular complications in COVID-19 patients were collected and a meta-analysis was designed and carried out to evaluate the risk of severity and mortality associated with high levels of CRP and D-dimer levels in COVID-19 patients. In addition, we aimed to describe the overall event rate of pre-existing cerebrovascular disease in COVID-19 patients. In our analysis, 5,614 cases have been studied, out of these patients 164 cases have developed cerebrovascular comorbities. Cerebrovascular comorbidity increased the risk of disease severity (odd ratio = 4.4; 95% CI: 1.48 to 12.84) and mortality (odd ratio = 7.0; 95% CI: 2.56 to 18.99). Statistical analyses showed that CRP and D-dimer serum levels were elevated by six-folds in the severe cases of COVID-19 patients. This significant increase in these two proteins levels can serve as a vital indicator for COVID-19 patients who are at increased risk of severe COVID-19 cerebrovascular complications, such as stroke.

d-dimer Level as a Predictor of Recurrent Stroke in Patients With Embolic Stroke of Undetermined Source

[Figure: see text].

Predictors of Brain Natriuretic Peptide Serum Level Elevation in Patients with Symptomatic Chronic Subdural Hematoma: A Prospective Study

Background: Brain natriuretic peptide serum levels (BNP) on admission are frequently elevated in patients with symptomatic chronic subdural hematoma (cSDH) and predict unfavorable long-term functional outcomes. However, the reasons for these elevated levels remain unclear. Therefore, we aimed to identify the predictors of BNP elevation. Methods: Patients with unilateral symptomatic cSDH who were surgically treated in our department between November 2016 and May 2020 were enrolled. Patients’ symptoms and neurological deficits were prospectively assessed using a study questionnaire. On initial computer tomography, hematoma volumes and midline shift (MLS) values were measured to analyze the degree of brain compression. Results: In total, 100 patients were analyzed. Linear regression analysis showed that higher BNP levels were significantly associated with smaller hematoma volumes (p = 0.003) and littler MLS values (p = 0.022). Multivariate analysis revealed that presence of a neurological deficit (p = 0.041), a hematoma volume < 140 mL (p = 0.047), advanced age (p = 0.023), and head trauma within 24 h of admission (p = 0.001) were independent predictors of BNP elevation. Conclusion: In symptomatic cSDH, BNP elevation is related, among others, to the presence of neurological deficits and smaller hematoma volumes. Whether BNP elevation may coincide with the early stage of hematoma growth, i.e., immaturity of cSDH neomembrane, requires further investigations.

Large vessel cardioembolic stroke and embolic stroke of undetermined source share a common profile of matrix metalloproteinase-9 level and susceptibility vessel sign length

BACKGROUND

Embolic stroke of undetermined source (ESUS) accounts for up to 25% of ischemic strokes. Identification of biomarkers that could improve the prediction of stroke subtype and subsequently of stroke prevention still remains a major issue.

METHODS

The HIBISCUS-STROKE cohort includes ischemic stroke patients with large vessel occlusion treated with mechanical thrombectomy following admission magnetic resonance imaging. Presence and length of susceptibility vessel sign (SVS) were assessed by gradient-recalled echo T2*-weighted imaging. Matrix metalloproteinase-9 (MMP-9) was measured on sera collected at admission. A multiple logistic regression model was performed to detect independent markers distinguishing cardioembolic (CE) from large-artery atherosclerosis (LAA) subtype.

RESULTS

A total of 147 patients were included, of them the etiology was distributed as follows: 86 (58.5%) CE, 26 (17.7%) LAA, and 35 (23.8%) ESUS. The optimal cutoff for differentiating CE from LAA subtype was 14.5 mm for SVS length (sensitivity, 79.7%; specificity, 72.7%) and 1110 ng/ml for admission MMP-9 level (sensitivity, 85.3%; specificity, 52.2%). Multivariate analysis revealed that current smoking (odds ratio [OR] 0.07, 95% confidence interval [CI] 0.01-0.93), tandem occlusion (OR 0.01, 95% CI 0.01-0.21), SVS length (OR 0.78, 95% CI 0.63-0.97), and admission MMP-9 level (OR 0.99, 95% CI 0.99-1.00) were inversely associated with CE subtype. SVS length and MMP-9 level did not differ between ESUS and CE subtypes.

CONCLUSION

SVS length and admission MMP-9 level may improve the prediction of CE subtype whose profile is close to ESUS, thus suggesting a common cardiac embolic source.

Serum LRG1 as a novel biomarker for cardioembolic stroke

BACKGROUND

In recent years, LRG1 was found to be closely related to atrial fibrillation, heart failure, and myocardial remodeling after myocardial infarction. While its role in cerebral infarction was still controversial. We aimed to explore the value of LRG1 to identify the cardioembolic stroke.

METHODS

283 acute ischemic stroke(AIS) patients and 169 controls were enrolled. The AIS patients were divided into a CE(cardiogenic embolism) group and a non-CE group. Serum LRG1 levels were quantified by ELISA.

RESULTS

The serum LRG1 levels were decreased in the AIS patients. CE group had higher serum LRG1 levels than the non-CE group. LRG1 was an independent risk factor for cardioembolic stroke. The area under the curve (AUC) was 0.768 with a sensitivity of 72.5% and specificity of 69.5%, which was not second to BNP and LAD. The combined predictive model we designed, including LRG1, BNP, and LAD, greatly improved the prediction effect. A positive correlation was shown between LRG1 and stroke severity in the CE group. Those who experienced poor outcomes had higher serum LRG1 levels compared with good ones.

CONCLUSION

Serum LRG1 was a promising indicator to predict cardioembolic stroke, as well as stroke severity and the 3-month prognosis of it.

Characterizing thrombus with multiple red blood cell compositions by optical coherence tomography attenuation coefficient

Embolectomy is one of the emergency procedures performed to remove emboli. Assessing the composition of human blood clots is an important diagnostic factor and could provide guidance for an appropriate treatment strategy for interventional physicians. Immunostaining has been used to identity compositions of clots as a gold-standard procedure, but it is time-consuming and cannot be performed in situ. Here, we proposed that the optical attenuation coefficient of optical coherence tomography (OCT) can be a reliable indicator as a new imaging modality to differentiate clot compositions. Fifteen human blood clots with multiple red blood cell (RBC) compositions from 21% to 95% were prepared using healthy human whole blood. A homogeneous gelatin phantom experiment and numerical simulation based on the Lambert-Beer's law were examined to verify the validity of the attenuation coefficient estimation. The results displayed that optical attenuation coefficients were strongly correlated with RBC compositions. We reported that attenuation coefficients could be a promising biomarker to guide the choice of an appropriate interventional device in a clinical setting and assist in characterizing blood clots.

Promising Biomarker Candidates for Cardioembolic Stroke Etiology. A Brief Narrative Review and Current Opinion

Determining the cause of stroke is considered one of the main objectives in evaluating a stroke patient in clinical practice. However, ischemic stroke is a heterogeneous disorder and numerous underlying disorders are implicated in its pathogenesis. Although progress has been made in identifying individual stroke etiology, in many cases underlying mechanisms still remain elusive. Since secondary prevention strategies are tailored toward individual stroke mechanisms, patients whose stroke etiology is unknown may not receive optimal preventive treatment. Cardioembolic stroke is commonly defined as cerebral vessel occlusion by distant embolization arising from thrombus formation in the heart. It accounts for the main proportion of ischemic strokes, and its share to stroke etiology is likely to rise even further in future decades. However, it can be challenging to distinguish cardioembolism from other possible etiologies. As personalized medicine advances, stroke researchers' focus is increasingly drawn to etiology-associated biomarkers. They can provide deeper insight regarding specific stroke mechanisms and can help to unravel previously undetected pathologies. Furthermore, etiology-associated biomarkers could play an important role in guiding future stroke prevention strategies. To achieve this, broad validation of promising candidate biomarkers as well as their implementation in well-designed randomized clinical trials is necessary. This review focuses on the most-promising candidates for diagnosis of cardioembolic stroke. It discusses existing evidence for possible clinical applications of these biomarkers, addresses current challenges, and outlines future perspectives.

Blood biomarkers to detect new-onset atrial fibrillation and cardioembolism in ischemic stroke patients

BACKGROUND

Accumulating data suggest blood biomarkers could inform stroke etiology.

OBJECTIVE

The purpose of this study was to investigate the performance of multiple blood biomarkers in elucidating stroke etiology with a focus on new-onset atrial fibrillation (AF) and cardioembolism.

METHODS

Between January and December 2017, information on clinical and laboratory parameters and stroke characteristics was prospectively collected from ischemic stroke patients recruited from the National University Hospital, Singapore. Multiple blood biomarkers (N-terminal pro-brain natriuretic peptide [NT-proBNP], d-dimer, S100β, neuron-specific enolase, vitamin D, cortisol, interleukin-6, insulin, uric acid, and albumin) were measured in plasma. These variables were compared with stroke etiology and the risk of new-onset AF and cardioembolism using multivariable regression methods.

RESULTS

Of the 515 ischemic stroke patients (mean age 61 years; 71% men), 44 (8.5%) were diagnosed with new-onset AF, and 75 (14.5%) had cardioembolism. The combination of 2 laboratory parameters (total cholesterol ≤169 mg/dL; triglycerides ≤44.5 mg/dL) and 3 biomarkers (NT-proBNP ≥294 pg/mL; S100β ≥64 pg/mL; cortisol ≥471 nmol/l) identified patients with new-onset AF (negative predictive value [NPV] 90%; positive predictive value [PPV] 73%; area under curve [AUC] 85%). The combination of 2 laboratory parameters (total cholesterol ≤169 mg/dL; triglycerides ≤44.5 mg/dL) and 2 biomarkers (NT-proBNP ≥507 pg/mL; S100β ≥65 pg/mL) identified those with cardioembolism (NPV 86%; PPV 78%; AUC 87%). Adding clinical predictors did not improve the performance of these models.

CONCLUSION

Blood biomarkers could identify patients with increased likelihood of cardioembolism and direct the search for occult AF.

Characterizing blood clots using acoustic radiation force optical coherence elastography and ultrasound shear wave elastography

Thromboembolism in a cerebral blood vessel is associated with high morbidity and mortality. Mechanical thrombectomy (MT) is one of the emergenc proceduresperformed to remove emboli. However, the interventional approaches such as aspiration catheters or stent retriever are empirically selected. An inappropriate selection of surgical devices can influence the success rate during embolectomy, which can lead to an increase in brain damage. There has been growing interest in the study of clot composition and using a priori knowledge of clot composition to provide guidance for an appropriate treatment strategy for interventional physicians. Developing imaging tools which can allow interventionalists to understand clot composition could affect management and device strategy. In this study, we investigated how clots of different compositions can be characterized by using acoustic radiation force optical coherence elastography (ARF-OCE) and compared with ultrasound shear wave elastography (SWE). Five different clots compositions using human blood were fabricated into cylindrical forms from fibrin-rich (21% red blood cells, RBCs) to RBC-rich (95% RBCs). Using the ARF-OCE and SWE, we characterized the wave velocities measured in the time-domain. In addition, the semi-analytical finite element model was used to explore the relationship between the phase velocities with various frequency ranges and diameters of the clots. The study demonstrated that the wave group velocities generally decrease as RBC content increases in ARF-OCE and SWE. The correlation of the group velocities from the OCE and SWE methods represented a good agreement as RBC composition is larger than 39%. Using the phase velocity dispersion analysis applied to ARF-OCE data, we estimated the shear wave velocities decoupling the effects of the geometry and material properties of the clots. The study demonstrated that the composition of the clots can be characterized by elastographic methods using ARF-OCE and SWE, and OCE demonstrated better ability to discriminate between clots of different RBC compositions, compared to the ultrasound-based approach, especially in clots with low RBC compositions.

Role of Blood-Based Biomarkers in Ischemic Stroke Prognosis: A Systematic Review

BACKGROUND AND PURPOSE

Outcome prognostication in ischemic stroke patients remains challenging due to limited predictive properties of existing models. Blood-based biomarkers might provide additional information to established prognostic factors. We intended to identify the most promising prognostic biomarkers in ischemic stroke, their incremental prognostic value, and whether their predictive value differs among etiologies.

METHODS

We searched MEDLINE (Ovid) and Institute for Scientific Information Web of Knowledge for articles reporting the predictive performance of blood-based biomarkers measured up to 7 days after ischemic stroke and reporting functional outcome or death at least 7 days after stroke. This work updates a previous systematic review (up to January 2007), follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement and was registered (International Prospective Register of Systematic Reviews PROSPERO 2018; https://www.crd.york.ac.uk/PROSPERO/; Unique identifier: CRD42018094671).

RESULTS

Two hundred ninety-one articles published between January 2007 and August 2018 comprising 257 different biomarkers met inclusion criteria. Median sample size was 232 (interquartile range, 110-455); 260 (89%) articles reported regression analyses with 78% adjusting for stroke severity, 82% for age, 67% for both, and 9% for none of them; 37% investigated discrimination, 5% calibration, and 11% reclassification. Including publications from a previous systematic review (1960-January 2007), natriuretic peptides, copeptin, procalcitonin, mannose-binding lectin, adipocyte fatty acid-binding protein, and cortisol were the biomarkers most consistently associated with poor outcome in higher-quality studies showing an incremental value over established prognostic factors. Other biomarkers were less consistently associated with poor outcome or were reported in lower quality studies. High heterogeneity among studies precluded the performance of a meta-analysis.

CONCLUSIONS

The number of reports on prognostic blood-based biomarkers in ischemic stroke increased 3.5-fold in the period January 2007 to August 2018. Although sample size increased, methodological flaws are still common. Natriuretic peptides and markers of inflammation, atherogenesis, and stress response are the most promising prognostic biomarkers among identified studies.

Changes of Metabolites in Acute Ischemic Stroke and Its Subtypes

Existing techniques have many limitations in the diagnosis and classification of ischemic stroke (IS). Considering this, we used metabolomics to screen for potential biomarkers of IS and its subtypes and to explore the underlying related pathophysiological mechanisms. Serum samples from 99 patients with acute ischemic stroke (AIS) [the AIS subtypes included 49 patients with large artery atherosclerosis (LAA) and 50 patients with small artery occlusion (SAO)] and 50 matched healthy controls (HCs) were analyzed by non-targeted metabolomics based on liquid chromatography–mass spectrometry. A multivariate statistical analysis was performed to identify potential biomarkers. There were 18 significantly different metabolites, such as oleic acid, linoleic acid, arachidonic acid, L-glutamine, L-arginine, and L-proline, between patients with AIS and HCs. These different metabolites are closely related to many metabolic pathways, such as fatty acid metabolism and amino acid metabolism. There were also differences in metabolic profiling between the LAA and SAO groups. There were eight different metabolites, including L-pipecolic acid, 1-Methylhistidine, PE, LysoPE, and LysoPC, which affected glycerophospholipid metabolism, glycosylphosphatidylinositol-anchor biosynthesis, histidine metabolism, and lysine degradation. Our study effectively identified the metabolic profiles of IS and its subtypes. The different metabolites between LAA and SAO may be potential biomarkers in the context of clinical diagnosis. These results highlight the potential of metabolomics to reveal new pathways for IS subtypes and provide a new avenue to explore the pathophysiological mechanisms underlying IS and its subtypes.

Role of brain natriuretic peptide in the prediction of long-term surgical outcome of chronic subdural hematoma

OBJECTIVE

To investigate the role of brain natriuretic peptide (BNP) in predicting long-term functional outcome and develop a new predictive score of poor functional outcome after surgery for chronic subdural hematoma (cSDH).

METHODS

Patients with cSDH that were surgically treated in our department between November 2016 and December 2019 were included in the study. Pre- and postoperative plasma BNP and clinical condition were prospectively recorded. At follow-up (5-6 months), a simplified modified Rankin Scale (mRS) questionnaire was conducted through a standardized telephone interview. A poor outcome was defined by a mRS > 3. Based on predictors of the long-term functional outcome, a score was calculated. Its accuracy was tested using the area under the curve (AUC) of the receiver operating characteristic analysis.

RESULTS

In total, 119 patients were analyzed (median age: 76 years, range: 44-94 years). Preoperative plasma BNP (BNP-1) was elevated in 77 patients (64.7%). For the follow-up phone interview, 101 patients (84.8%) were available. In the multivariate analysis, poor outcome at follow-up could be predicted using BNP-1 (p = 0.034), age (p = 0.036), motor deficit (p = 0.013) and Glasgow coma scale score on admission (p = 0.008). The "Functional Long-term Outcome Predictive score" (FLOP-score) was therefore computed, and revealed an excellent discriminative capacity compared to other scores, with an AUC of 0.86 (0.77-0.95).

CONCLUSIONS

Preoperative plasma BNP is an independent predictor of functional outcome at follow-up. Using the FLOP-score, the risk of experiencing a poor outcome could accurately be predicted.

High incidence of stroke in COVID-19 patients

A retrospective analysis of 11 COVID-19 patients complicated with stroke was performed. It was found that the incidence of stroke in patients with COVID-19 was significantly higher than the average level of the general population (P=0.003), and the D-dimer levels of 11 stroke patients were significantly higher than other patients (P=0.004). The significant increase of D-dimer can be used as an early warning indicator of cerebral infarction. It is critical to have a response plan for treating acute stroke in COVID-19 patients.

Atrial fibrillation: villain or bystander in vascular brain injury

Atrial fibrillation (AF) and stroke are inextricably connected, with classical Virchow pathophysiology explaining thromboembolism through blood stasis in the fibrillating left atrium. This conceptualization has been reinforced by the remarkable efficacy of oral anticoagulant (OAC) for stroke prevention in AF. A number of observations showing that the presence of AF is neither necessary nor sufficient for stroke, cast doubt on the causal role of AF as a villain in vascular brain injury (VBI). The requirement for additional risk factors before AF increases stroke risk; temporal disconnect of AF from a stroke in patients with no AF for months before stroke during continuous ECG monitoring but manifesting AF only after stroke; and increasing recognition of the role of atrial cardiomyopathy and atrial substrate in AF-related stroke, and also stroke without AF, have led to rethinking the pathogenetic model of cardioembolic stroke. This is quite separate from recognition that in AF, shared cardiovascular risk factors can lead both to non-embolic stroke, or emboli from the aorta and carotid arteries. Meanwhile, VBI is now expanded to include dementia and cognitive decline: research is required to see if reduced by OAC. A changed conceptual model with less focus on the arrhythmia, and more on atrial substrate/cardiomyopathy causing VBI both in the presence or absence of AF, is required to allow us to better prevent AF-related VBI. It could direct focus towards prevention of the atrial cardiomyopathy though much work is required to better define this entity before the balance between AF as villain or bystander can be determined.

D-dimer and Body CT to Identify Occult Malignancy in Acute Ischemic Stroke

BACKGROUND AND AIM

Patients with acute ischemic stroke associated with cancer have D-dimer elevations greater than those with acute ischemic stroke or cancer alone. While D-dimer has been proposed as a screening tool to identify such patients, its use in clinical practice to identify malignancy and to inform the use of CT scanning has not been well characterized.

METHODS

We conducted a retrospective cohort study of patients with acute ischemic stroke to evaluate how D-dimer levels and CT chest, abdomen, and pelvis scanning were used in practice to screen for occult malignancy. Patients were excluded if they had known active cancer and or received tPA.

RESULTS

Of 480 patients, 254 (53%) had D-dimer measured, 49 (10%) underwent CT screening for cancer, and 11 (2%) had findings concerning for malignancy. There was no difference in D-dimer level between patients who underwent CT evaluation for cancer and those who did not (median 1.01 vs 0.85 p = 0.19). Patients with CT concerning for cancer had higher D-dimer levels than those with a negative CT (median 2.52 vs 0.74 p = 0.01). D-dimer demonstrated moderate discrimination with a c-statistic of 0.77. Selecting a cut point of >1.2 ug/mL (60^th percentile of our cohort and 2.4-times the upper limit of normal for our institution's D-dimer assay) provided a sensitivity of 85% and specificity of 65%, a positive likelihood ratio of 2.32, and an odds ratio of 9.6 (95% confidence interval 2.1-44.1, p = 0.004) for having a CT scan concerning for malignancy.

CONCLUSIONS

Elevated D-dimer levels are suggestive of occult malignancy in acute ischemic stroke patients and should inform selective use of CT to screen for cancer.

Free Fatty Acids in CSF and Neurological Clinical Scores: Prognostic Value for Stroke Severity in ICU

Introduction

Brain ischemia initiated significant increase in FFAs in animal studies. Accumulation of FFA can lead to liberation of inflammatory byproducts that contribute to neuronal death. Increased risk of systemic thromboembolism was seen in animal models after FFA infusion possibly through activation of factor XII by stearic acids. The clinical studies that examined the relation between stroke in humans and CSF biomarkers are infrequent. Aim of Work. We tried to evaluate the potential role of FFAs in CSF in the diagnosis and the prognosis of ICU patients with AIS while comparing the results to traditional neurological scoring systems. Patients and Methods. Our study included 80 patients who were admitted to ICU with acute ischemic stroke (AIS) within 24 hours of the onset of cerebral infarction. CSF samples were obtained at admission. The FFA levels were measured using the sensitive enzyme-based colorimetric method. The NIHSS, GCS, and mRS were evaluated at admission and at 30 days. Univariate and multivariate analysis were used to evaluate the stroke outcome according to FFA levels in CSF.

Results

Worsening of the GCS (<7) at 30 days showed a significant correlation with FFA in CSF. The ROC curve showed a cutoff value of 0.27 nmol/µl, sensitivity of 62.9%, and specificity of 72.2%. There was a significant correlation between FFA in CSF and the mRS >2 at 30 days. The ROC curve showed a cutoff value of 0.27 nmol/µl, specificity of 69.2%, and sensitivity of 59.7%. There was a significant correlation between FFA in CSF and the NIHSS ≥ 16 at 30 days. The ROC curve showed a cutoff value of 0.27 nmol/µl, specificity of 72.2%, and sensitivity of 62.9%. Our study subdivided patients according to infarction volume and compared the 2 subgroups with FFA in CSF. We found a significant difference between 2 subgroups. FFA levels showed a positive correlation with infarction volume ≥145 ml. The ROC curve showed a cutoff value of 0.25 nmol/µl, sensitivity of 76.9%, and specificity of 71.4%. Our study showed that FFA in CSF was a significant predictor of all-cause mortality (0.37 + 0.26, P value 0.007). The ROC curve showed a cutoff value of 0.27, specificity of 72.2%, and sensitivity of 62.9%. There was a positive correlation between FFA in CSF and neurological causes of mortality (0.48 + 0.38, P value 0.037). The ROC curve showed a cutoff value of 0.37 nmol/µl, specificity of 76.1%, and sensitivity of 61.5%.

Conclusion

FFA in CSF may serve as an independent prognostic biomarker for assessing the prognosis of acute ischemic stroke and the clinical outcome. It might be a useful biomarker for early detection of high-risk patients for poor outcome and hence more aggressive treatment.

Analysis of Brain Natriuretic Peptide Serum Levels in Patients with Symptomatic Chronic Subdural Hematoma: A Potential Reliable Biomarker

The purpose of this study was to analyze brain natriuretic peptide (BNP) serum levels of patients with chronic subdural hematoma (cSDH) and their clinical implication. Patients with cSDH who underwent surgery in our department between November 2016 and October 2019 were eligible for enrollment in the study. Patients with recurrent bleedings, traumatic brain injury, cSDH associated with other intracranial pathologies, and those with a history of congestive heart failure, renal or endocrine disease were excluded. We measured BNP serum levels pre- and post-operatively and at discharge. The BNP values were analyzed with respect to patient medical history and neurological condition. The Glasgow Coma Scale score and the modified Rankin Scale score classified the clinical and neurological condition at the time of admission and discharge, respectively. The data of 100 surgically treated patients with cSDH (mean age 73.2, range 42 − 94 years, male/female 3.5:1) were analyzed. Pre-operative BNP serum levels (BNP-1) were elevated in 67% of the patients (n = 67; median = 101.6 pg/mL; p < 0.001). These serum levels increased after surgery (p < 0.001) and decreased thereafter (p < 0.001), reaching a level at discharge (day 7) that was not statistically different from BNP-1 (p > 0.05). In addition, elevated BNP-1 showed a significant statistical association with the presence of atrial fibrillation (p < 0.01) and antiplatelet and/or anticoagulant therapy (p < 0.01). This study provides new evidence regarding BNP serum levels and their secretion pattern in patients with cSDH. Whether BNP-1 can predict the long-term functional outcome of patients with cSDH is being investigated in this ongoing prospective study.

A novel approach to treatment of thromboembolic stroke in mice: Redirecting neutrophils toward a peripherally implanted CXCL1-soaked sponge

Neutrophils are considered key participants in post-ischemic stroke inflammation. They are the first white blood cells to arrive in ischemic brain and their presence in the brain tissue positively correlates with post-ischemic injury severity. CXCL1 is a neutrophil attractant chemokine and the present study evaluates whether redirecting neutrophil migration using a peripherally implanted CXCL1-soaked sponge can reduce brain inflammation and improve outcomes in a novel mouse model of thromboembolic (TE) stroke. TE stroke was induced by injection of a platelet-rich microemboli suspension into the internal carotid artery of adult C57BL/6 male mice. The model induced neuroinflammation that was associated with increases in multiple brain and serum cytokines/chemokines at the mRNA and protein levels, including very marked increases in CXCL1. In other groups of animals, an absorbable sterile hemostatic sponge, previously immersed in either saline (0.9%NaCl) or CXCL1, was implanted into subcutaneous pockets formed in the inguinal region on the left and right side following stroke surgery. Mice implanted with the sponge soaked with CXCL1 had significantly reduced neuroinflammation and infarct size after TE stroke compared to mice implanted with the sponge soaked with 0.9%NaCl. There was also reduced mortality and improved neurological deficits in the TE stroke + CXCL1 sponge group compared to the TE stroke +0.9%NaCl sponge group. In conclusion: redirecting bloodstream leukocytes toward a peripherally-implanted neutrophil chemokine CXCL1-soaked sponge improves outcomes in a novel mouse model of thromboembolic stroke. The present findings suggest a novel therapeutic strategy for patients with acute stroke.