Main Cause Of Ischemic Stroke Research Articles

Clinical and Therapeutic Aspects of Ischemic Stroke in Atrial Fibrillation at the Neurology Department of CHU Conakry

Introduction: The main cause of ischemic stroke in our setting is atrial fibrillation. The aim of this study was to evaluate the clinical and therapeutic aspects of atrial fibrillation during ischemic stroke. Material and Methods: We conducted a retrospective descriptive study lasting one year from November 1, 2020 to November 31, 2021, involving all patients with ischemic stroke diagnosed by CT or MRI. We included patients with atrial fibrillation confirmed by a 12-lead électrocardiogrammes (ECG) or a 24-hour ECG holter. Thromboembolic risk was assessed by the CHA2DS2Vasc score and bleeding risk by the HAS-BLED score. Results: A total of 1,400 patients (19.64%) were enrolled. Mean age was 57.3 +/-16.64 years, predominantly female (54.5%), with hypertension as a risk factor (45.09%). The mean NIHSS score was 17.9 +/-3.2, associated with disorders of consciousness (44.36%) and hemiplegia (100%). atrial fibrillation was persistent in 54.90% of cases. A CHA2DS2-VASc score ≥ 2 was found in 94.9% of cases, and a low HAS-BLED score in 73% of cases, for whom Rivaroxaban was the first-line treatment in 76.72% of cases. Conclusion: This study has shown that atrial fibrillation is common in cardioembolic cerebral infarctions with age and hypertension as risk factors.

Minimally invasive left atrial appendage occlusion plus reduced dose direct oral anticoagulant to prevent stroke in patients with atrial fibrillation-the LAAO-PlusRE.

The onset of atrial fibrillation (AF) has a direct association with left atrial appendage (LAA) function, as demonstrated by recent studies demonstrating the link between left atrial (LA) wall fibrosis, impaired contractility, and the development of AF. Non-valvular AF (NVAF) affects almost 30 million people worldwide, with this number expected to increase in the next 20 years. It is the main cause of ischemic stroke, with significant subsequent economic and social impact. Currently, the mainstay of stroke prevention in patients with NVAF is oral anticoagulation (OAC), which reduces the incidence of ischemic events at the stake of increased hemorrhagic events. Despite the introduction and widespread use of direct oral anticoagulants (DOACs), which almost completely replaced vitamin K antagonists (VKAs), the adherence to OAC is still low, hindering the efficacy of stroke prevention. Percutaneous LAA occlusion (LAAO) is now indicated (class IIB) in patients with NVAF at increased ischemic risk who cannot undergo OAC. Recently published data demonstrated that a reduced dose of DOAC after percutaneous LAAO is superior to long-term dual antiplatelet therapy (DAPT) for stroke prevention in the mid-term. One of the possible pitfalls of percutaneous LAAO is postprocedural peri-device leaks (PDLs) that have been associated with increased thromboembolic events. According to LAAOS III results, surgical LAAO during cardiac surgery brings a 33% reduction in risk of stroke at five years, independently from the OAC regimen with a high rate of complete appendage occlusion. The combination of surgical LAAO and reduced dose DOAC might ensure adequate embolic prevention, lowering the hemorrhagic risk. The present manuscript aims to describe the rationale and design of the Minimally Invasive Left Atrial Appendage Occlusion Plus REduced Dose DOAC To Prevent Stroke In Patients With Atrial Fibrillation Randomized Clinical Trial (LAAO-PlusRE).

Diagnosis of atrial fibrillation in young patients with ischemic stroke: A systematic review and meta-analysis

IntroductionThe recommended cardiac rhythm evaluation to determine the etiology of ischemic stroke (IS) is similar in all patients regardless of their age and includes an electrocardiogram and at least a 24-hour heart rhythm monitoring. However, it is known that the main causes of IS vary according to patients’ age. There is a higher preponderance of arterial dissections and patent foramen ovale in younger patients, while atrial fibrillation (AF) is more common in older patients. AimsTo determine the proportion of AF in young IS reported in the literature and determine if young IS patients found to have AF had known structural cardiac pathology. MethodsSystematic review of the literature searching PubMed and Embase for articles published since their inception to August 2020. Inclusion criteria were studies including at least 10 patients, aged 14-50 years-old, clinical or radiological diagnosis of IS and quantification of patients found to have AF. We conducted a meta-analysis using a random-effects model and calculated pooled proportions with 95% confidence intervals. Results8331 articles were screened, 154 were selected for full-text review. 43 studies were included in our final analysis (902800 patients). The proportion of AF in young IS overall was 3.1% [95%CI 2.4-3.7], I2 93.88%. Sub-analysis revealed a proportion of AF of 3.8% [95% CI 0.3-7.3] in lower-middle-income economies, versus 5.4% [95% CI 3-7.9] in upper-middle-income economies, and 2.2% [95% CI 1.6-2.8] in high-income economies. Only 3 studies mentioned the proportion of patients with AF that had structural cardiac pathology. ConclusionThe proportion of AF in young IS was low. More studies are needed to better understand if young IS patients diagnosed with AF had a priori known structural cardiac pathology that could increase the probability of finding AF. This could lead to a reevaluation of the need for 24 hours cardiac rhythm evaluation in young patients without cardiac pathology.

Update on Biomarkers Associated with Large-Artery Atherosclerosis Stroke.

Intracranial and extracranial large-artery atherosclerosis (LAA) are a main cause of ischemic stroke. Biomarkers may aid in the diagnosis of LAA and help to stratify patients' risk of stroke. We performed a narrative review of the literature, mainly published in the last five years, with the aim of identifying biomarkers associated either with intracranial or extracranial LAA in humans. Several potential biomarkers of LAA, mainly related to lipidic pathways and inflammation, have been studied. Diagnostic biomarkers of LAA were evaluated by measuring biomarkers levels in patients with LAA stroke and other stroke etiologies. Some biomarkers were associated with the functional prognosis of LAA stroke patients. Increased levels of IL-6 and sLOX-1 were associated with a risk of progression of carotid atherosclerotic disease. Findings support the notion that the immune system plays a central role in the pathogenesis of LAA. Overall, in most studies, results were not externally validated. In the future, biomarkers could be useful for the selection of patients for clinical trials. To adopt these biomarkers in clinical practice, we will need robust multicentric studies proving their reproducibility and a clear practical applicability for their use.

LC-MS/MS based metabolomic analysis of serum from patients with cerebrovascular stenosis

Cerebrovascular stenosis (CVS) is the main cause of ischemic stroke, which greatly threatens human life. Hence, it’s important to perform early screenings for CVS. Metabolomics is an emerging omics approach that has great advantages in disease screening and diagnosis. Therefore, we aim to elucidate the correlation between CVS and metabolomics, which can aid in conducting CVS screening at an early stage. Patients with CVS in Beijing Hospital were included in the study. A total of 36 participants, including 18 patients diagnosed with CVS and 18 healthy individuals, were recruited at Beijing Hospital between May 2022 and October 2021. The serum samples were analyzed for liquid chromatography-tandem mass spectrometry (LC-MS/MS). Then, multivariate statistical methods, including principal component analysis (PCA), partial least squares-discriminant analysis (PLS-DA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) were performed. Differential metabolites were obtained and demonstrated by volcano plot and heatmap. The study recruited 36 participants, including 18 patients with CVS and 18 healthy participants. A total of 150 metabolites were identified. Multivariate statistical analysis revealed significant differences between patients and healthy participants. Furthermore, 30 serum metabolites levels differed significantly between two groups. Differential metabolites were enriched in phenylalanine, tyrosine, and tryptophan biosynthesis; primary bile acid biosynthesis, and other pathways. This study identified differential metabolites in patients with CVS and elucidated the relevant metabolic pathways. Thus, these findings aid in the study of the pathogenesis of CVS and its early diagnosis. Data Availability StatementThe datasets generated for this study are available on request to the corresponding author.

New Technologies in the Assessment of Carotid Stenosis: Beyond the Color-Doppler Ultrasound-High Frame Rate Vector-Flow and 3D Arterial Analysis Ultrasound.

Atherosclerotic plaque in the carotid artery is the main cause of ischemic stroke, with a high incidence rate among people over 65 years. A timely and precise diagnosis can help to prevent the ischemic event and decide patient management, such as follow up, medical, or surgical treatment. Presently, diagnostic imaging techniques available include color-Doppler ultrasound, as a first evaluation technique, computed tomography angiography, which, however, uses ionizing radiation, magnetic resonance angiography, still not in widespread use, and cerebral angiography, which is an invasively procedure reserved for therapeutically purposes. Contrast-enhanced ultrasound is carving out an important and emerging role which can significantly improve the diagnostic accuracy of an ultrasound. Modern ultrasound technologies, still not universally utilized, are opening new horizons in the arterial pathologies research field. In this paper, the technical development of various carotid artery stenosis diagnostic imaging modalities and their impact on clinical efficacy is thoroughly reviewed.

Circadian gene CLOCK accelerates atherosclerosis by promoting endothelial autophagy

ABSTRACT Atherosclerosis (AS) is a chronic inflammatory disease which gives rise to life-threatening complications like ischemic stroke. Rupture of carotid atherosclerotic plaque is the main cause of ischemic stroke. Emerging evidence has demonstrated that disturbed circadian rhythms could accelerate the progression of atherosclerosis by regulating endothelial function. Moreover, our previous study implicated the circadian gene circadian locomotor output cycles kaput (CLOCK) in the pathogenesis of unstable plaques. In this study, we explored the underlying mechanism that CLOCK mediates endothelial cell autophagy involved in the progression of AS. Circadian and autophagy gene expression was analyzed in the GSE41571 dataset and human carotid atherosclerotic plaque samples. Then we used ox-LDL to treat HUVECs, and analyzed CLOCK and autophagy gene in endothelial cells. Besides that, we comprehensively analyzed in vivo experiments to explore the function of CLOCK in autophagy and atherosclerosis using different staining including HE, MT and IF staining. In the dataset and patient samples, CLOCK expression and autophagy were decreased in the unstable plaque group compared with the stable group. Decreased Beclin1, ATG5, LC3, and CLOCK were also observed in HUVECs under oxidative stress condition which also enhances cell proliferation. In vivo, we also found decreasing level of CLOCK, Beclin1, LC3 and ATG5 in ApoE−/− mice compared with WT mice. Silencing of CLOCK in ApoE−/− mice may further aggravate atherosclerosis including decreased cap thickness and collagens. Our findings implicated that downregulation CLOCK would impair endothelial cell autophagy and accelerate atherosclerotic plaque, which provides a novel strategy for treatment of progression in AS.

Using eZIS of SPECT to evaluate the therapeutic effect of carotid endarterectomy.

Stroke is an acute cerebrovascular disease with high morbidity and mortality. The main causes of ischemic stroke include carotid artery stenosis, and carotid endarterectomy (CEA) can be used to improve the blood flow of the lesion site. Regional cerebral blood flow (rCBF) can be decreased by using single photon emission computed tomography (SPECT). The Easy Z-Score imaging system (eZIS) can display the changes of rCBF as Z-Score. The purpose of this study was to determine whether eZIS of SPECT can be used to evaluate the therapeutic effect of CEA in the treatment of carotid artery stenosis. In this study, subjects were divided into the surgery group and the control group. The surgery group included seven patients with unilateral or bilateral internal carotid artery stenosis who received CEA treatment, and the control group included 11 patients who only received conventional drug treatment but did not receive surgery. Cerebral perfusion imaging (CPI) was collected twice before and after the corresponding treatment (within 6 months). rCBF of the lesion site was measured and Z-score was calculated before and after treatment by the eZIS technique. The postoperative Z-score of the surgery group was 0.54 ± 2.71 compared with that of the preoperative -1.34 ± 2.68 ( P = 0.0034; t = 4.687; df = 6), while the z-score of the control group was -0.33 ± 2.58 compared with that of the pretreatment 1.84 ± 2.62 ( P = 0.0010; t = 4.618; df = 10). CEA can effectively improve the blood flow in the lesion area of patients with carotid artery stenosis. eZIS of SPECT can be used to evaluate the therapeutic effect of CEA on carotid artery stenosis visually.

Bioinformatic identification of potential biomarkers and therapeutic targets in carotid atherosclerosis and vascular dementia.

Vascular disease is the second most common cause of dementia. The prevalence of vascular dementia (VaD) has increased over the past decade. However, there are no licensed treatments for this disease. Carotid atherosclerosis (CAS) is highly prevalent and is the main cause of ischemic stroke and VaD. We studied co-expressed genes to understand the relationships between CAS and VaD and further reveal the potential biomarkers and therapeutic targets of CAS and VaD. CAS and VaD differentially expressed genes (DEGs) were identified through bioinformatic analysis Gene Expression Omnibus (GEO) datasets GSE43292 and GSE122063, respectively. Furthermore, a variety of target prediction methods and network analysis approaches were used to assess the protein-protein interaction (PPI) networks, the Gene Ontology (GO) terms, and the pathway enrichment for DEGs, and the top 7 hub genes, coupled with corresponding predicted miRNAs involved in CAS and VaD, were assessed as well. A total of 60 upregulated DEGs and 159 downregulated DEGs were identified, of which the top 7 hub genes with a high degree of connectivity were selected. Overexpression of these hub genes was associated with CAS and VaD. Finally, the top 7 hub genes were coupled with corresponding predicted miRNAs. hsa-miR-567 and hsa-miR-4652-5p may be significantly associated with CAS and VaD.

Correlation between morphological and biomechanical features and carotid atherosclerosis

The main cause of ischemic stroke is the atherosclerotic lesions of the carotid arteries. Unlike other arteries, carotid arteries have unique anatomical structure and hemodynamic characteristics, which are significantly related to the occurrence of atherosclerosis.
 Thus, a proper understanding of the functional anatomy, local hemodynamics of the carotid arteries and their relationship with the atherosclerotic process can improve the quality of early diagnosis and treatment of carotid artery stenosis, which, in turn, will reduce the risk of developing of the ischemic cerebrovascular diseases.

Imaging diagnosis and research progress of carotid plaque vulnerability.

Ischemic stroke (IS) exhibits a high disability rate, mortality, and recurrence rate, imposing a serious threat to human survival and health. Its occurrence is affected by various factors. Although the previous research has demonstrated that the occurrence of IS is mainly associated with lumen stenosis caused by carotid atherosclerotic plaque (AP), recent studies have revealed that many patients will still suffer from IS even with mild carotid artery lumen stenosis. Blood supply disturbance causes 10% of IS to the corresponding cerebral blood supply area caused by carotid vulnerable plaque. Thrombus blockage of distal branch vessels caused by rupture of vulnerable carotid plaque is the main cause of ischemic stroke. Therefore, how to accurately evaluate vulnerable plaque and intervene as soon as possible is a problem that needs to be solved in clinic. The vulnerability of plaque is determined by its internal components, including thin and incomplete fibrous cap, necrotic lipid core, intra-plaque hemorrhage, intra-plaque neovascularization, and ulcerative plaque formation. The development of imaging technology enables the routine detection of AP vulnerability. By analyzing the pathological changes, characteristics, and formation mechanism of carotid plaque vulnerability, this article aims to explore the modern imaging methods which can be used to identify plaque composition and plaque vulnerability to provide a reference basis for disease diagnosis and differential diagnosis.

Detecting the vulnerable carotid plaque: the Carotid Artery Multimodality imaging Prognostic study design.

Carotid artery disease is highly prevalent and a main cause of ischemic stroke and vascular dementia. There is a paucity of information on predictors of serious vascular events. Besides percentage diameter stenosis, international guidelines also recommend the evaluation of qualitative characteristics of carotid artery disease as a guide to treatment, but with no agreement on which qualitative features to assess. This inadequate knowledge leads to a poor ability to identify patients at risk, dispersion of medical resources, and unproven use of expensive and resource-consuming techniques, such as magnetic resonance imaging, positron emission tomography, and computed tomography. The Carotid Artery Multimodality imaging Prognostic (CAMP) study will: prospectively determine the best predictors of silent and overt ischemic stroke and vascular dementia in patients with asymptomatic subcritical carotid artery disease by identifying the noninvasive diagnostic features of the 'vulnerable carotid plaque'; assess whether 'smart' use of low-cost diagnostic methods such as ultrasound-based evaluations may yield at least the same level of prospective information as more expensive techniques. We will compare the prognostic/predictive value of all proposed techniques with regard to silent or clinically manifest ischemic stroke and vascular dementia. The study will include ≥300 patients with asymptomatic, unilateral, intermediate degree (40-60% diameter) common or internal carotid artery stenosis detected at carotid ultrasound, with a 2-year follow-up. The study design has been registered on Clinicaltrial.gov on December 17, 2020 (ID number NCT04679727).

Multicomponent material property characterization of atherosclerotic human carotid arteries through a Bayesian Optimization based inverse finite element approach

ObjectivePlaque rupture in atherosclerotic carotid arteries is a main cause of ischemic stroke and it is correlated with high plaque stresses. Hence, analyzing stress patterns is essential for plaque specific rupture risk assessment. However, the critical information of the multicomponent material properties of atherosclerotic carotid arteries is still lacking greatly. This work aims to characterize component-wise material properties of atherosclerotic human carotid arteries under (almost) physiological loading conditions. MethodsAn inverse finite element modeling (iFEM) framework was developed to characterize fibrous intima and vessel wall material properties of 13 cross sections from five carotids. The novel pipeline comprised ex-vivo inflation testing, pre-clinical high frequency ultrasound for deriving plaque deformations, pre-clinical high-magnetic field magnetic resonance imaging, finite element modeling, and a sample efficient machine learning based Bayesian Optimization. ResultsThe nonlinear Yeoh constants for the fibrous intima and wall layers were successfully obtained. The optimization scheme of the iFEM reached the global minimum with a mean error of 3.8% in 133 iterations on average. The uniqueness of the results were confirmed with the inverted Gaussian Process (GP) model trained during the iFEM protocol. ConclusionThe developed iFEM approach combined with the inverted GP model successfully predicted component-wise material properties of intact atherosclerotic human carotids ex-vivo under physiological-like loading conditions. SignificanceWe developed a novel iFEM framework for the nonlinear, component-wise material characterization of atherosclerotic arteries and utilized it to obtain human atherosclerotic carotid material properties. The developed iFEM framework has great potential to be advanced for patient-specific in-vivo application.

Improvement of the management of anticoagulation in Atrial Fibrillation patients in the emergency and acute medical departments; a service quality improvement report

Atrial fibrillation (AF) is considered one of the main causes of ischemic stroke. The CHA2DS2VASC score can predict the stroke risk. Proper anticoagulation can significantly reduce such risk. Anticoagulation involves a risk of bleeding, which can be predicted by the HAS-BLED score. The non-documentation of both AF risk scores in the medical notes of patients presenting with acute or paroxysmal AF has alerted our team, for fear of missing administering the proper anticoagulation. A baseline audit showed that the CHA2DS2VASC score was documented in 27% of such patients, while the HAS-BLED score was documented in 5% of them. A quality improvement project was planned and included two PDSA cycles over a period of five months. The first cycle was based on raising the awareness of the junior doctors on risk assessment of AF patients and the importance of anticoagulation prescription. This involved educational posters, emails, and presentations. On the second cycle, the baseline audit showed a 69% improvement (from 27% to 46%) in the rate of CHA2DS2VASC score assessment and a 140% improvement (from 5% to 12%) in the rate of HAS-BLED scoring. However, the rate of anticoagulation prescription remained almost the same in both cycles (55% and 52%). A doctors’ survey showed that they are not quite comfortable prescribing long-term anticoagulation on acute care units because of the inadequate assessment of the bleeding risk, and the associated comorbidities that can disturb the action of the oral anticoagulants. They preferred to refer the patient to a specialised AF clinic for further assessment and prescription. On auditing the patient referral on discharge, it was found that 91% of the patient were seen at the AF clinic in 2 weeks. The remainders were referred to their GP for further assessment and prescription. That seemed to be a safer way of anticoagulation prescription for such patients.

CircRNA‑0006896‑miR1264‑DNMT1 axis plays an important role in carotid plaque destabilization by regulating thebehavior of endothelial cells in atherosclerosis.

Atherosclerosis (AS) is a chronic inflammatory disease of the vascular wall with multiple causes. AS is the primary pathological basis of cardiovascular disease and stroke. Moreover, carotid plaque rupture and thrombus formation are the main causes of ischemic stroke. Therefore, understanding the formation of carotid plaques may help improve the prediction and prevention of cardiovascular and cerebrovascular events. Endothelial cell dysfunction results in re-endothelialization and angiogenesis in atherosclerotic plaques, thus promoting plaque destabilization. The aim of the present study was to evaluate the effect of circular RNA (circRNA) molecules in serum exosomes (serum-Exos) from patients with stable plaque atherosclerosis (SA) and unstable/vulnerable plaque atherosclerosis (UA). Specifically, the effect of circRNA on human umbilical vein endothelial cell (HUVEC) behavior and the mechanisms underlying plaque destabilization in AS were evaluated. Serum-Exos were isolated, then identified using transmission electron microscopy, nanoparticle tracking analysis and western blotting. The serum-Exo-circRNA expression profile of patients with SA or UA was investigated using a circRNA array. The relationship between circRNA-006896 in serum-Exos and biochemical parameters of patients with SA and UA were analyzed using Spearman's correlation. In addition, HUVECs were incubated with serum-Exos for in vitro functional assays. The present study demonstrated that circRNAs expression profiles in SA and UA serum-Exos were significantly different, indicating a potential role for circRNAs in carotid plaque destabilization. The expression of circRNA-0006896 was positively correlated with triglyceride, low-density lipoprotein cholesterol (LDL-C) and C-reactive protein levels, and negatively correlated with albumin levels in patients with UA. However, circRNA-0006896 expression was positively correlated with LDL-C in patients with SA. Using bioinformatic analysis, a competing endogenous RNA (ceRNA) network was selected to study the regulatory roles of circRNA-0006896 in serum-Exos. Additionally, in HUVECs treated with serum-Exos derived from patients with UA, the expression of circRNA-0006896 in HUVECs was upregulated. This was accompanied by decreased expression of microRNA-1264 and SOCS3, increased levels of DNMT1 and phosphorylated STAT3. HUVEC proliferation and migration were significantly increased in the UA group, compared with the mock and SA groups. This finding indicates that the circRNA-0006896-miR-1264-DNMT1 axis plays an important role in carotid plaque destabilization by regulating the behavior of endothelial cells. Moreover, it suggests that circRNA-0006896 may represent a therapeutic target for controlling JNK/STAT3 signaling in HUVECs. Thus, this study may provide insight on potential interventions against vulnerable plaque formation in patients with AS.

Is carotid artery stenting without protection safe? - A single center experience: case series

Background: Carotid artery stenosis is one of the main causes of ischemic stroke in Iranian population. Carotid artery stenting (CAS) is a method with for treating carotid artery disease, in order to prevent stroke. Dispersion of the embolus is a significant risk for carotid angioplasty which can be prevented by using protective devices. But studies have shown that the use of these protective devices is not safe and can have side effects such as vascular spasm and dissection. Method: 36 patients who underwent unprotected carotid artery angioplasty from April 2018 to August 2019 in Shahid Madani hospital retrospectively entered this study. Hospital records were studied for data collection. Patients were followed by phone interviews. Major adverse cardiovascular and cerebral events (MACCE) was defined as a composite of the occurrence of stroke, MI, bleeding, and all-cause mortality in the long term. Mean duration of our follow-up was 6 months. Results: During in-hospital course, an 82 years old woman with a history of CVA, hypertension, diabetes and a significant stenosis in her contralateral ICA, had an episode of stroke which was fatal. Also, there was a 46 years old woman without any risk factors, who had developed intracranial hemorrhage (ICH). 22 patients were followed. No MI, stroke, or death occurred in any of the patients. There were only 2 cases of bleeding. Conclusion: Carotid artery stenting without protection may be is a safe method of carotid revascularization. Further prospective studies and clinical trials are needed.

Imaging of the vulnerable carotid plaque: Role of imaging techniques and a research agenda.

Atherothrombosis in the carotid arteries is a main cause of ischemic stroke and may depend on plaque propensity to complicate with rupture or erosion, in turn related to vulnerability features amenable to in vivo imaging. This would provide an opportunity for risk stratification and-potentially-local treatment of more vulnerable plaques. We here review current information on this topic. We systematically reviewed the literature for concepts derived from pathophysiologic, histopathologic, and clinical studies on imaging techniques attempting at identifying vulnerable carotid lesions. Ultrasound, MRI, CT, and nuclear medicine-based techniques, alone or with multimodality approaches, all have a link to pathophysiology and describe different-potentially complementary-aspects of lesions prone to complications. There is also, however, a true paucity of head-to-head comparisons of such techniques for practical implementation of a thorough and cost-effective diagnostic strategy based on evaluation of outcomes. Especially in asymptomatic patients, major international societies leave wide margins of indecision in the advice to techniques guiding interventions to prevent atherothrombotic stroke. To improve practical management of such patients-in addition to the patient's vulnerability for systemic reasons-a more precise identification of the vulnerable plaque is needed. A better definition of the diagnostic yield of each imaging approach in comparison with the others should be pursued for a cost-effective translation of the single techniques. Practical translation to guide future clinical practice should be based on improved knowledge of the specific pathophysiologic correlates and on a comparative modality approach, linked to subsequent stroke outcomes.

RARE CAUSES OF ISCHEMIC STROKE. FEATURES OF ACUTE STROKE IN PATIENTS WITH DISSECTION OF THE GREAT VESSELS

Purpose of the study . Identification of the main causes of ischemic stroke in patients with aortic dissection, features of the clinical picture, the choice of optimal tactics for the management of such patients. Patients and methods . During 2017, 11 patients with aortic dissection were hospitalized for emergency indications and underwent complex, surgical interventions. In 4 patients, the reason for hospitalization was ischemic stroke, in 7 patients, the onset of the disease was manifested by chest pain. Subsequently, in all cases, ischemic stroke developed within 48 hours from the onset of pain symptoms. Fatal outcomes occurred in 5 (45.45%). Results . All patients were operated on for aortic dissection. Various types of surgery were performed. The best results were achieved with a hybrid operation — prosthetics of the aortic arch with endoprosthetic replacement of the de­scending aorta. The main reason for the development of ischemic stroke with aortic dissection and surgery for its elimi­nation is the development of brain malfunction. The cause of death was the dissemination of the dissection into the vis­ceral arteries with the development of multiple organ failure or aortic rupture of the aorta with hemo tamponade. Conclusion . As a rule, several pools of blood supply to the brain, episodes of psychomotor excitement are involved in the dissection of the aorta and branches of the aortic arch, cognitive impairments are progressing, since cortical branch­es of the brain are usually involved. With the timely assignment of neuroprotective therapy, revascularization, early complex rehabilitation, there is a significant positive dynamics of neurological status, restoration of cognitive functions.

The evaluation of the sense of hearing in patients with carotid artery stenosis within the extracranial segments

Stenosis of arteries that supplies blood to the brain is one of the main causes of ischemic stroke which is the third most common cause of deaths in Europe. Atherosclerosis of carotid and vertebral arteries is responsible for 20% of the ischemic stroke cases. Stenosis may be either asymptomatic or manifested with typical neurological symptoms including motor and sensory disturbances as well as disturbances in vision and speech. However, discrete non-specific symptoms of ischemia, including headaches and vertigo, tinnitus and hearing loss, are also quite common. These symptoms may be indicative of a clinically significant stenosis of carotid and vertebral arteries, particularly within the internal carotid artery region, as well as of a risk of ischemic stroke. To date, research reports were unable to provide exact explanation of correlations between impaired hearing and the stenosis of carotid and vertebral arteries. Despite this, numerous articles list these symptoms as one of the first non-specific symptoms of this disorder. The ischemic mechanism within the inner ear region may lead to early symptoms of atherosclerosis of large vessels. However, no evidence of relationship and no explanation could be provided with this regard. The objective of the study was to assess the effect of carotid and vertebral artery stenosis on the function of the hearing and equilibrium organ on the basis of diagnostic audiological examinations including pure-tone threshold audiometry, impedance audiometry, otoacoustic emission tests and brainstem auditory evoked potential tests. The study was conducted in 63 patients (32 males, 31 females) aged 45–75 years, presenting with carotid and vertebral artery stenosis and treated at the Vascular Surgery Clinic of the University Clinical Hospital in Wrocław. Patients were stratified into two subgroups according to their age (45–60 years, 61–75 years). Patients were also divided into subgroups according to the stenotic arteries and to the symptomatic/asymptomatic status of the disorder. All patients were homogeneous in terms of the degree of artery stenosis. The control group consisted of 32 healthy persons (14 males, 18 females) aged 48–75 years. Patients qualified to the control group reported no history of middle or inner ear disorders, disturbed hearing, vertigo and balance disorders, as well as cardiovascular diseases; they also presented with unremarkable ultrasound scans of the arteries. All patients were subjected to precise audiological examinations. Prior to being qualified for the study, patients were subjected to the assessment of arteries by means of Doppler ultrasonography. The hearing organ function was assessed by means of pure-tone threshold audiometry, impedance audiometry, otoacoustic emission tests and brainstem auditory evoked potential tests. Reduction of the flow through the carotid arteries causes problems in the organ of hearing; abnormalities are reported especially in tone threshold audiometry, examinations of the stapedius muscle reflexes and brainstem auditory evoked potentials, which prove the presence of receptive cochlear–extracochlear hearing damage. Disturbances of the organ of hearing have similar severity in stenosis of the internal carotid artery and vertebral artery. Abnormalities found in audiologic examinations in patients with carotid artery stenosis are not always explicitly clinically expressed in patients with hearing loss; we should consider diagnostics for carotid artery stenosis.

Association analysis of Glutathione S-transferase omega-1 and omega-2 genetic polymorphisms and ischemic stroke risk in a Turkish population

ABSTRACTObjectives: Oxidative stress is a known risk factor for the pathogenesis of atherosclerosis, the main cause of ischemic stroke. Glutathione S-transferase (GST) omega-1 and omega-2, members of phase II enzymes, play a role in the antioxidant system. The single nucleotide polymorphisms (SNPs), C419A and A424G in GST omega genes can cause a decrease in enzyme activity. The aim of this study was to investigate the possible association between these polymorphisms and ischemic stroke risk in a Turkish population.Methods: The genotypes and allele frequencies for 239 patients and 130 controls were determined by the PCR/RFLP method. No significant differences were found between patients and controls in terms of genotype and allele frequencies.Results: The frequency of the polymorphic ‘A’ allele was 0.358 in patients and 0.342 in controls for the C419A polymorphism in the GSTO1 gene. The frequency of the polymorphic ‘G’ allele for GSTO2 A424G SNP was 0.370 in patients and 0.404 in controls. The combined homozygous wild type genotype ‘CCAG’ was significantly higher in control group than in the patients.Conclusion: No significant difference was observed between the stroke patients and controls in terms of genotypes and allele distributions. Double combine haplotype CCAA was found to be protective against ischemic stroke when compare to other haplotypes. However, different genotypes of GSTO1 and GSTO2 were observed to have effects on stroke risk in subgroups of diabetics and smokers. In conclusion, the current study is the first to report this finding.