View clinical trials related to Carotid Atherosclerosis.
Filter by:About 20% of strokes are caused by emboli deriving from a carotid plaque. In symptomatic patients with carotid stenosis grater than 70% the Carotid Endarterectomy (CEA) reduces stroke risk by about 75% and is generally accepted as being cost effective. However also in these cases there is a part of the population that, according to the morphological plaque characteristics, could better benefit from a conservative medical treatment. Improving the Best Medical Treatment, the situation seems to be even less clear in asymptomatic patients, where probably it would need to treat at least 32 patients in order to prevent one single ictus. Different parameters have been considered in order to determine, among the asymptomatic patients the ones that more than others could benefit from a surgical revascularisation instead of a medical treatment. Between these parameters, the quality of the plaque (vulnerability) and the micro-embolic signals (MES) detection with the Transcranial Doppler (TCD) Holter seems to be the most relevant. Another interesting aspect is trying to establish whether plaques can determine a different embolic risk in relation to the different histological findings. Therefore, it seems interesting and reasonable trying to establish a correlation between these two parameters in asymptomatic patients as in the symptomatic ones in order to make more and more appropriate a surgical plaque removal according to the specific risk of each patient in a set of tailored surgery. It consists in a descriptive observational study, since it intends to describe the embolic signals detection (MES) counted in automatic way with the TCD Holter, in patients affected by carotid stenosis, before and after the surgical operation. In particular it consists in a monocentric, longitudinal, prospective cohort study since it intends to analyse a group of patients (already candidates to CEA) that experiences a specific event (MES) before and after the surgical plaque removal, in a precise span of time. Since the treatment, removing the plaque, should remove the embolic focus too, a significant reduction of microembolic signals in post-operative time is expected. This reduction has been esteemed around about the 70% among candidates to CEA. Patients taken on responsibility of the equipe will undergo an ultrasonographic investigation for the carotid stenosis, histological characterization of the plaque based on the Gray-Weale classification and TCD-Holter for MES.
Carotid endarterectomy (CEA) and carotid stenting (CAS) are often performed for subgroups of patients for whom procedural benefit has not been established in randomised trials and despite evidence of serious procedural risk. In some places, the COVID-19 pandemic has made it difficult or impossible to perform CEA and CAS in time. This study aims to measure the rate of ipsilateral stroke and other complications in individuals with symptomatic carotid stenosis, whom for any reason are managed using current best medical intervention alone. The investigators expect at least 50% lowering of the ipsilateral stroke rate compared to that seen with medical intervention alone in past randomised trials.
In the entire world most people die from cardiovascular disease. Death is primarily from myocardial infarction (MI) and stroke which are most often caused by rupture of atherosclerotic plaques. Patients with high-grade, i.e. ≥ 70% carotid artery stenosis are at especially high risk. Magnetic Resonance Imaging (MRI) studies show that two features inside plaques that are associated with the risk of plaque rupture and subsequent cardiovascular events are: lipid rich necrotic core (LRNC) and intraplaque hemorrhage (IPH). MRI studies on carotid artery plaques typically relies on proton-density-weighted fast-spin echo, blood-suppressed T1- and T2-weighted gradient-echo sequences. The end-result is nonquantitative measures, where plaque features are identified due to their relative signal intensity. To address these problems of non-specificity, we developed a quantitative MRI (qMRI) technique based on Dixon sequences. The study intention is to enable in-depth analysis of plaque features and their relation to clinical data. For example there is an insufficient understanding of associations between lipid biomarkers and plaque contents. Our hypothesis is that we can identify quantitative changes in both plaque and lipid biomarkers after one year of optimized cardiovascular risk management (including treatment with lipid lowering drugs), and establish if there is any associations between these features. Because there is a well-established link between systemic inflammation and the presence of atherosclerotic plaques we will also study the relationship between LRNC and IPH as measured by qMRI versus circulating markers of inflammation. Method: Patients with known carotid stenosis are invited for a baseline visit and a 1-year follow up visit. The study visits include clinical assessment, blood tests, patient interview and magnetic resonance imaging of the carotid arteries. All participants are offered optimized cardiovascular risk management through the individual assessment by the study physicians.
Carotid artery disease is a main cause of ischemic stroke and vascular dementia, and a highly prevalent disease. There is uncertainty about the optimal management of patients with serendipitously or systematically detected asymptomatic carotid artery disease, due to the paucity of information on the predictive features of serious vascular events. While percent diameter stenosis is currently the accepted standard to decide about local interventions (carotid artery stenting or endarterectomy), international guidelines also recommend the evaluation of qualitative features of carotid artery disease as a guide to treatment. There is, however, no agreement on which qualitative features are best predictors of events. Furthermore, a role for metabolic plaque profile, local mechanical and hemorheologic factors in triggering microembolization and silent ischemic events has been proposed from experimental studies. This inadequate knowledge leads to a poor ability to identify patients at higher risk and to an unwarranted dispersion of medical resources, lack of standardization in diagnostic methods, and the use of expensive and resource-consuming techniques. Against this background, the investigators aim at: 1. Prospectively identifying the best predictors of (silent and overt) ischemic stroke and vascular dementia in patients with asymptomatic subcritical carotid artery disease, by identifying the non-invasive diagnostic features of the "vulnerable carotid plaque" as a possible guide for optimal - local and systemic - treatment. 2. Transferring new ultrasound techniques possibly improving risk prediction to the clinical field 3. Assess whether "smart", low-cost diagnostic methods, such as ultrasound-based evaluations integrating established and advanced techniques, may yield at least the same level of prospective information as more expensive and less cost-effective techniques.
This is an open-label, non-randomized study conducted at Thomas Jefferson University comparing pressure-gradient estimates (obtained between a carotid plaque and the carotid artery) to imaging and histology markers of plaque vulnerability. There is an inverse relationship between the subharmonic signal magnitude from contrast-enhanced ultrasound microbubbles and ambient pressure. This pressure estimation technique (referred as SHAPE) will be used to estimate the pressure gradient across the carotid plaque cap noninvasively in vivo.
Stroke is a common clinical disease with high disability and mortality, which seriously threatens human life and health.Carotid atherosclerotic plaque rupture is an important pathogenic basis of ischemic stroke, so judging the stability of plaque has important clinical significance in preventing ischemic stroke.Ultrasound, as a convenient, rapid, noninvasive, radiation-free auxiliary examination technology, is widely used in carotid plaque stability examination.At present, there are many methods to judge the stability of carotid plaque based on ultrasound, including two-dimensional ultrasound, contrast-enhanced ultrasound, ultrasound elastography and so on. However, the results of plaque stability judgment by various technologies deviate greatly, which is not conducive to the development of standardized diagnosis and treatment strategies by clinicians.Studies have shown that because the neovascular epidermal cells in atherosclerotic plaques are imperfect, they are easy to rupture after stress, and the ruptured neovasculature will lead to intraplaque hemorrhage, thus causing plaque shedding, and eventually obstructing the cerebrovascular cause stroke.Contrast-enhanced ultrasound can sensitively detect the distribution and course of blood vessels.The plaque's softness and hardness determine its stability, while the difference of lipids, fibers and calcium in the plaque determines its softness and hardness.Real-time ultrasound elastography can provide tissue mechanical parameters, express the soft and hard of tissue with strain value, and provide important reference information for judging plaque stability.At present, elastography technology is used to reflect the hardness of plaque, so as to further judge its stability.However, the elastography parameters are prone to deviations due to the influence of the selected section and the selected region of interest.Deep learning is the hottest research method in AI at present. [Deep learning is essentially to construct machine learning models with multiple hidden layers, and use large-scale data to train to obtain a large number of more representative feature information, so as to use these features to classify and predict samples. At present, it is widely used in the field of image analysis and plays an important role in medicine.Such as pathological image detection, regulatory genomics research, diagnosis of retinopathy and quantitative analysis of liver fibrosis, etc.Computational Fluid Dynamics (CFD) is a new discipline developed by the combination of numerical calculation and classical fluid mechanics theory. It can make it convenient for researchers to build a geometric model of cardiovascular system, simulate the real structure of vascular wall and blood, and display the results of "numerical experiments" using visualization technology.More intuitive Comprehensive response to changes in hemodynamic parameters In recent years, its application in cardiovascular hemodynamic research has become increasingly widespread, with a large number of relevant literature reports However, no report has been reported on the study of carotid plaque stability and fluid dynamics using this technology Based on the above reasons,This study attempts to use AI technology to automatically identify and quantitatively evaluate the gray scale differences of plaques, elastic image characteristics of plaques, microvessel density division of plaque contrast-enhanced ultrasound, and velocity vector imaging (VVI) to determine plaque surface stress.To study the effect of hemodynamic parameters on carotid plaque using CFD technology, and to establish a systematic comprehensive evaluation system for carotid plaque stability, which integrates two-dimensional plaque information, texture information, microcirculation perfusion information, biomechanical information and blood flow field information, and combines the results of clinical follow-up and collagen fiber content of surgical specimens, MMP9/CD34 and other examinations.
: Use of novel radio-pharmaceutical 64CUDOTA-ECL1i to evaluate arterial atherosclrosis
Stroke is the second leading cause of death in the Western world and the leading cause of major lifelong disability. About 15% of strokes are secondary to thrombosis or embolization of an unstable atheromatous carotid plaque. In these symptomatic patients, the degree of carotid stenosis is correlated with the risk of early recurrence. Patients with stenosis over 70% are therefore offered an endarterectomy, an operation to remove carotid plaque, to prevent future strokes[1]. In asymptomatic patients, the degree of stenosis is a limited predictor, and better risk stratification is required to assess the degree of plaque vulnerability and stroke risk of the patient. The therapeutic decision towards endarterectomy in addition to drug therapy is debated because of a variable and dependent benefit/risk balance for each patient. A number of imaging parameters have been studied: ulceration, heterogeneity, vascularization of the plaque for example, but their place is not well defined [2]. The usual evaluation of carotid stenosis is by conventional Doppler ultrasound with calculation of the degree of stenosis according to the NASCET criteria. For symptomatic stenoses the intervention is recommended when above 70% and is discussed from 50% to 70% of NASCET stenosis degree. For asymptomatic stenoses, the procedure is discussed when above 60% taking into account the patient's life expectancy, the risk of the surgery and the unstable nature of the plaque [2]. Destabilization of the carotid plaque is partially induced by inflammation associated with neo-vascularization. The detection of these new vessels by conventional contrast ultrasound has already shown a distinction between stable and unstable plaques, by the presence or absence of microbubbles in the plaque. However, this assessment is not very precise and only the most vascularized plaques can be detected. Ultrafast ultrasound Imaging is a new ultrasonic Imaging modality that allows detecting low speed flows, a tiny vascular structure within the vessel wall. RESEARCH HYPOTHESIS Plaques neo-vascularization would be more precisely detected and characterized by ultrafast imaging coupled with microbubble injection than conventional ultrasound imaging. A better assessment of plaque instability could improve the selection of patients for carotid endarterectomy and increase the benefit/risk ratio of this preventive surgery.
Develop adverse event prediction and plaque phenotype classification models for patients with known or suspected carotid artery disease.
Intraplaque hemorrhage (IPH) is one of the main features of the carotid plaque instability's and predictor of ischemic stroke. Benefits (on the basis on benefit/risk ratio) of the carotid endarterectomy remain unclear for stroke asymptomatic patients; thus, more and more patients with important stenosis (i.e. over 60%) detected are not operated. However, these patients need adapted therapeutic treatments to limit plaque instability and this should include physical activity (PA). Indeed, PA has been showed to decrease numerous inflammatory markers involved in atherosclerosis. It has also recently been reported on stroke asymptomatic patients that the prevalence of carotid IPH was decreased in those with higher level of PA. Magnetic Resonance Imaging (MRI) of the IPH has been shown to be the better non-invasive imaging technique to assess carotid plaque instability and in particular IPH. Here, the aim of this study is to assess the effect of an individualized home-based 6 months physical activity intervention on carotid IPH and other biomarkers of vulnerability for asymptomatic patients. This study has been designed as a monocentric, longitudinal and interventional study. This study will involve one centre: Hopital Louis Pradel (HCL, Lyon). After inclusion tests, patients will be randomly included in the control group, or in the PA group. Patients of the PA group will have connected bracelets to measure daily count of steps. Twice a month, daily goals will be revaluated to increase or maintain the steps per day. The final goal is to reach 6 000 steps per day or increase by 30% the initial count of steps per day. Same tests will be done after 6 months of intervention for comparison.