Transient ischemic attack and minor stroke: diagnosis, risk stratification and management

CLINICAL APPLICATION STUDY OF 3D-ASL PERFUSION IMAGING AND MAGNETIC RESONANCE DIFFUSION IMAGING IN TRANSIENT ISCHEMIC ATTACK

ABSTRACT

Objective: This study aimed to explore the clinical application of three-dimensional arterial spin labeling (3D-ASL) and diffusion-weighted magnetic resonance imaging (DWI) in transient ischemic attacks. Methods: Forty patients with transient cerebral ischemia in our hospital were selected and included from July 2020 to March 2022. All subjects were detected by DWI and 3D-ASL technology. The positive rate, relative cerebral blood flow (rCBF), and the receiver operating characteristic curve of the two methods in the diagnosis of transient cerebral ischemia were compared; the objective was to compare the relationship between the frequency of transient ischemic attack and hypoperfusion, and vascular stenosis. Results: The 3D-ASL examination showed two cases of hypoperfusion in the healthy control group (5.00), and the magnetic resonance imaging examination showed four cases of vascular stenosis in the healthy control group (10.00). The rCBF ratio in the cerebral ischemia group was significantly lower than that in the cerebral ischemia group, which was significantly lower than that in the healthy control group ( P < 0.05). The area under the curve (AUC) of 3D-ASL in the diagnosis of transient cerebral ischemia was 0.800, and the AUC of DWI in the diagnosis of transient cerebral ischemia was 0.725. The AUC of the combination of the two methods in transient cerebral ischemia was 0.850. There was a significant difference in the attack frequency of patients with transient cerebral ischemia with different perfusion ( P < 0.05). There was a significant difference in attack frequency between patients with transient ischemic attack and patients without vascular stenosis ( P < 0.05). Conclusion: 3D-ASL and DWI technology have higher diagnostic efficiency for transient cerebral ischemia.

Considering Context-Specific microRNAs in Ischemic Stroke with Three "W": Where, When, and What

MicroRNAs are short non-coding RNA molecules that function as critical regulators of various biological processes through negative regulation of gene expression post-transcriptionally. Recent studies have indicated that microRNAs are potential biomarkers for ischemic stroke. In this review, we first illustrate the pathogenesis of ischemic stroke and demonstrate the biogenesis and transportation of microRNAs from cells. We then discuss several promising microRNA biomarkers in ischemic stroke in a context-specific manner from three dimensions: biofluids selection for microRNA extraction (Where), the timing of sample collection after ischemic stroke onset (When), and the clinical application of the differential-expressed microRNAs during stroke pathophysiology (What). We show that microRNAs have the utilities in ischemic stroke diagnosis, risk stratification, subtype classification, prognosis prediction, and treatment response monitoring. However, there are also obstacles in microRNA biomarker research, and this review will discuss the possible ways to improve microRNA biomarkers. Overall, microRNAs have the potential to assist clinical treatment, and developing microRNA panels for clinical application is worthwhile.

Derivation of a clinical prediction score for the diagnosis of clinically significant symptomatic carotid artery disease

OBJECTIVES

Emergent vascular imaging identifies a subset of patients requiring immediate specialized care (i.e. carotid stenosis > 50%, dissection or free-floating thrombus). However, most TIA patients do not have these findings, so it is inefficient to image all TIA patients in crowded emergency departments (ED). Our objectives were to derive and internally validate a clinical prediction score for clinically significant carotid artery disease in TIA patients.

METHODS

This was a planned secondary analysis of a prospective cohort study from 14 Canadian EDs. Among 11555 consecutive adult ED patients with TIA/minor stroke symptoms over 12 years, 9882 had vascular imaging and were included in the analysis. Our main outcome was clinically significant carotid artery disease, defined as extracranial internal carotid stenosis ≥ 50%, dissection, or thrombus in the internal carotid artery, with contralateral symptoms.

RESULTS

Of 9882 patients, 888 (9.0%) had clinically significant carotid artery disease. Logistic regression was used to derive a 13-variable reduced model. We simplified the model into a score (Symcard [Symptomatic carotid artery disease] Score), with suggested cut-points for high, medium, and low-risk stratification. A substantial portion (38%) of patients were classified as low-risk, 33.8% as medium risk, and 28.2% as high risk. At the low-risk cut-point, sensitivity was 92.9%, specificity 41.1%, and diagnostic yield 1.7%.

CONCLUSIONS

This simple score can predict carotid artery disease in TIA patients using readily available information. It identifies low-risk patients who can defer vascular imaging to an outpatient or specialty clinic setting. Medium-risk patients may undergo imaging immediately or with slight delay, depending on local resources. High-risk patients should undergo urgent vascular imaging.

Transient speech impairment: a minor stroke/TIA case escaping conventional imaging methods

This case report discusses the diagnostic challenges posed by transient ischaemic attacks (TIAs) and minor strokes presenting with atypical symptoms, focusing on a 62-year-old male presenting with isolated speech difficulties reminiscent of Broca's aphasia. Despite initial inconclusive imaging, subsequent evaluation revealed minor periventricular changes consistent with ischaemic small vessel disease and a pre-existing lacunar infarct. The resolution of symptoms within 10 days highlights the transient nature of the event. The case underscores the importance of recognising nuanced presentations of cerebrovascular events and the necessity for standardised diagnostic criteria and assessment tools for transient speech impairments resembling Broca's aphasia. Further research into the mechanisms underlying these transient events, utilising advanced imaging techniques, such as diffusion-weighted MRI (DWI), may be warranted to facilitate early recognition and appropriate management in clinical practice.

Arterial transit artifacts and carotid Plaque-RADS may predict symptoms in patients with carotid stenosis

AIM

To analyze the correlation of carotid stenosis severity, the Plaque Reporting and Data System (RADS) score, arterial transit artifacts (ATAs), and cerebral blood flow (CBF) with clinical cerebral ischemic symptoms in patients with carotid artery stenosis (CAS).

MATERIALS AND METHODS

Sixty-one patients with unilateral internal carotid artery stenosis or occlusion (≥50% stenosis) diagnosed by ultrasound, Computed Tomography(CT) angiography, or Magnetic Resonance(MR) angiography in Yichang City Central People's Hospital from January 2022 to February 2024 were retrospectively enrolled and divided into two groups according to the presence or absence of symptoms. Both groups underwent MR plaque imaging and arterial spin labeling (ASL)-based 3.0 T MRI to compare the differences in stenosis degree, Plaque-RADS score, ATA grade, and CBF between the two groups. Binary regression analysis was used to identify the parameters with statistically significant differences between the two groups and to evaluate their diagnostic efficacy using the area under the workup curve of the subjects.

RESULTS

The Plaque-RADS score, ATA grade, and CBF differences in the anterior cerebral artery(ACA)blood supply region were correlated with symptoms, and the areas under the ROC curves for the CBF differences in the ACA blood supply region, Plaque-RADS score, ATA grade and a joint model that combines all three to predict symptoms in CAS patients were 0.672, 0.796, 0.788 and 0.919, respectively.

CONCLUSIONS

CBF, Plaque-RADS and ATAs were identified as independent risk factors for symptoms in patients with CAS and have a certain predictive value for symptoms, and the combined predictive value is greater, potentially providing a more effective imaging modality for clinical treatment and evaluation.

Emergency medicine updates: Transient ischemic attack

INTRODUCTION

Transient ischemic attack (TIA) is a condition commonly evaluated for in the emergency department (ED). Therefore, it is important for emergency clinicians to be aware of the current evidence regarding the diagnosis and management of this disease.

OBJECTIVE

This paper evaluates key evidence-based updates concerning TIA for the emergency clinician.

DISCUSSION

TIA is a harbinger of ischemic stroke and can result from a variety of pathologic causes. While prior definitions incorporated symptoms resolving within 24 h, modern definitions recommend a tissue-based definition utilizing advanced imaging to evaluate for neurologic injury and the etiology. In the ED, emergent evaluation includes assessing for current signs and symptoms of neurologic dysfunction, appropriate imaging to investigate for minor stroke or stroke risk, and arranging appropriate disposition and follow up to mitigate risk of subsequent ischemic stroke. Imaging should include evaluation of great vessels and intracranial arteries, as well as advanced cerebral imaging to evaluate for minor or subclinical stroke. Non-contrast computed tomography (CT) has limited utility for this situation; it can rule out hemorrhage or a large mass causing symptoms but should not be relied on for any definitive diagnosis. Noninvasive imaging of the cervical vessels can also be used (CT angiography or Doppler ultrasound). Treatment includes antithrombotic medications if there are no contraindications. Dual antiplatelet therapy may reduce the risk of recurrent ischemic events in higher risk patients, while anticoagulation is recommended in patients with a cardioembolic source. A variety of scoring systems or tools are available that seek to predict stroke risk after a TIA. The Canadian TIA risk score appears to have the best diagnostic accuracy. However, these scores should not be used in isolation. Disposition may include admission, management in an ED-based observation unit with rapid diagnostic protocol, or expedited follow-up in a specialty clinic.

CONCLUSIONS

An understanding of literature updates concerning TIA can improve the ED care of patients with TIA.

Physical activity modification following a Transient Ischemic Attack in individuals with diabetes

BACKGROUND

Individuals with diabetes exhibit a higher risk of cardiovascular disease and mortality compared to healthy individuals. Following a transient ischemic attack (TIA) the risk of stroke and death increase further. Physical activity engagement after a TIA is an effective way of secondary prevention. However, there's a lack of research on how individuals with diabetes modify physical activity levels and how these adjustments impact survival post-TIA. This study aimed to determine the extent to which individuals with diabetes alter their physical activity levels following a TIA and to assess the impact of these changes on mortality.

METHODS

This was a nationwide longitudinal study, employing data from national registers in Sweden spanning from 01/01/2003 to 31/12/2019. Data were collected 2 years retro- and prospectively of TIA occurrence, in individuals with diabetes. Individuals were grouped based on decreasing, remaining, or increasing physical activity levels after the TIA. Cox proportional hazards models were fitted to evaluate the adjusted relationship between change in physical activity and all-cause, cardiovascular, and non-cardiovascular mortality.

RESULTS

The final study sample consisted of 4.219 individuals (mean age 72.9 years, 59.4% males). Among them, 35.8% decreased, 37.5% kept steady, and 26.8% increased their physical activity after the TIA. A subsequent stroke occurred in 6.7%, 6.4%, and 6.1% of individuals, while death occurred in 6.3%, 7.3%, and 3.7% of individuals, respectively. In adjusted analyses, participants who increased their physical activity had a 45% lower risk for all-cause mortality and a 68% lower risk for cardiovascular mortality, compared to those who decreased their physical activity.

CONCLUSIONS

Positive change in physical activity following a ΤΙΑ was associated with a reduced risk of mortality. Increased engagement in physical activity should be promoted after TIA, thereby actively supporting individuals with diabetes in achieving improved health outcomes.

Effects of alteplase and aspirin on functional outcomes in patients with acute ischemic stroke and mild non-disabling neurological deficit

Investigate the effect of Alteplase and Aspirin on the functional outcomes of patients with acute ischemic stroke with mild non-disabling neurological deficit. In this single-center, randomized controlled study, we selected 60 patients with acute ischemic stroke with mild non-disabling neurological deficit admitted to our hospital from January 2021 to January 2022, and randomly divided them into the study group (n = 30) and the control group (n = 30), the control group was given the Aspirin treatment, the study group was given the Alteplase treatment, and the changes in neurological recovery, daily living ability, exercise ability, balance ability, cognitive function, and short-term prognosis outcomes were observed in these 2 groups. The factors influencing the short-term outcome of Alteplase therapy in patients with acute ischemic stroke were analyzed. The National Institutes of Health Neurological Deficit Score (NIHSS) scores at T1 and T2 of the study group were lower than those in the control group, but the scores of Barthel indicators (BI), Fugl-Meyer Motor Assessment Scale (FMA), Berg Balance Scale (BBS) and Montreal Cognitive Assessment Scale (MoCA) of the study group were higher than those in the control group, and the difference was statistically significant (P < .05). The short-term prognostic outcomes of these 2 groups were not significantly different (P > .05). The effect of the use of Alteplase or Aspirin on short-term functional outcomes in patients with acute ischemic stroke and mild non-disabling neurological deficit is not much different.

Transient ischemic attack and coronary artery disease: a two-sample Mendelian randomization analysis

Background

Although observational studies have shown that patients who experienced transient ischemic attacks (TIAs) had a higher risk of coronary artery disease (CAD), the causal relationship is ambiguous.

Methods

We conducted a two-sample Mendelian randomization (MR) study to analyze the causal relationship between TIA and CAD using data from the FinnGen genome-wide association study. Analysis was performed using the inverse-variance weighted (IVW) method. The robustness of the results was evaluated using MR-Egger regression, the weighted median, MR pleiotropy residual sum, and outlier (MR-PRESSO) and multivariable MR analysis.

Results

Results from IVW random-effect model showed that TIA was associated with an increased risk of coronary artery atherosclerosis (OR 1.17, 95% CI 1.06-1.28, P = 0.002), ischemic heart disease (OR 1.15, 95% CI 1.04-1.27, P = 0.007), and myocardial infarction (OR1.15, 95% CI 1.02-1.29, P = 0.025). In addition, heterogeneity and horizontal pleiotropy were observed in the ischemic heart disease results, while the sensitivity analysis revealed no evidence of horizontal pleiotropy in other outcomes.

Conclusions

This MR study demonstrated a potential causal relationship between TIA and CAD. Further research should be conducted to investigate the mechanism underlying the association.