View clinical trials related to Carotid Artery Plaque.
Filter by:Carotid artery stenosis due to atherosclerotic plaques accounts for an important cause of ischemic stroke. Current research seeks to risk stratify asymptomatic patients by characterizing rupture-prone plaques. Currently no single imaging modality can reliably identify those plaques before surgery. Recently, the 3D ultrasound (US) and the assessment of the mechanical stress on the vessel wall have been proposed as non-invasive tools that could play a role in the diagnostic work-up. Data of histological validation, however, are still needed. In this research, 3D US, non-invasive elastography, Finite Element Analysis of computed tomography angiography images and the study of the autonomic cardiovascular control will be used to identify preoperatively the vulnerable plaque in patients undergoing carotid endarterectomy. The results will be compared to that of histology of the removed plaque, aiming to provide a validation to each method for a possible application in the daily practice.
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.
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.
This study concentrates on providing more ultrasound image details when scanning vascular system including arterial and venous systems. A new sensor which provides 3D images is newly designed. It will be used in this study to find out whether it can change the future of vascular imaging or not.
The goal of this study is to evaluate the incidence of post procedure DW-MRI lesions (relative to baseline) and debris captured in the ENROUTE Transcarotid NPS inline filter during a transcarotid stenting procedure.
The goal of this evaluation is to document the incidence of post procedure DW-MRI lesions (relative to baseline) in patients treated with the transcarotid artery revascularization (TCAR) procedure.
In the present study, the investigators sought to prospectively examine the associations of plasma levels of TMAO (trimethylamine oxide), choline, betaine, dimethylglycine, and sarcosine with risk of incident carotid artery plaque, assessed by repeated B-mode carotid artery ultrasound imaging over a 7-year period, in women and men with and without HIV infection from the WIHS (Women Interagency HIV Study) and MACS (Multicenter Aids Cohort Study).
The researchers are trying to determine if the characterization of "vulnerable" carotid artery plaques can be accomplished with ultrasound-based methods that look for vessels in the plaque and measure the plaque stiffness.
Background-White matter hyperintensities (WMH), patchy areas of hyperintense signal on T2-weighted or Fluid Attenuated Inversion Recovery sequences on brain magnetic resonance imaging (MRI), are believed to reflect cerebral burden of ischemic damage and are associated to incident stroke, dementia and eventually mortality in otherwise healthy subjects. Also brain atrophy has been related with presence of carotid atherosclerosis and vascular cognitive impairment. Carotid atherosclerosis may contribute to the genesis of WMH. A recent meta-analysis by our group comprising 5306 subjects was able to demonstrate an association between the presence of carotid atherosclerosis and WMH (odds ratio, OR, 1.42, 95% confidence interval [CI] 1.22-1.66). Objective-To evaluate the relation between carotid artery plaque characteristics, cardiovascular risk factors and brain atrophy/WMH burden analyzed quantitatively as number and volume of lesions and as brain volumes, and progression over 18 months of follow up in subjects asymptomatic for cerebrovascular disease with a carotid artery stenosis <70%.
Broad Goal: To demonstrate that focused vascular ultrasound (FOVUS) can accurately risk stratify patients with chest pain in the emergency department (ED). Background and Rationale: Traditional risk assessment focuses on characteristics of the pain, known Coronary Artery Disease (CAD), risk factors, electrocardiogram (ECG), and blood tests to identify active ischemia. Identifying clinically significant CAD remains one of the most challenging tasks in the ED. Current clinical decision rules err on the side of over investigation and admission. To address this limitation, the Investigators have developed a point-of-care carotid ultrasound test predictive of CAD. The Investigators have shown that carotid plaque is strongly associated with significant angiographic CAD in a population referred for angiogram. Research Aims: Primary - To determine the association between carotid plaque measured by a dedicated sonographer and 30-day major adverse cardiac events (MACE), including MI, reperfusion, or death in patients presenting to the ED with suspected cardiac ischemia. Secondary - To determine the agreement sonographer and emergency physician FOVUS results. Methodology: The Investigators propose a prospective cohort study to assess the prognostic value of a novel point-of-care carotid ultrasound plaque quantification protocol in the ED of Kingston General Hospital. We will enroll 500 consecutive patients presenting with a chief complaint of chest pain prompting at least one 12-lead ECG and troponin measurement. Patients will undergo carotid scan by a dedicated sonographer and emergency physician. Patients will be followed for MACE for 30 days. Those performing scans will be blinded to clinician's impression and care plans while clinicians will be blinded to FOVUS findings. The primary analysis will involve determination of the sensitivity, sensitivity, positive predictive value, negative predictive value and likelihood ratios associated with FOVUS for 30-day MACE. Expected Outcomes: The study will provide evidence to determine whether FOVUS may be a useful prognostic tool for emergency physicians assessing patients with suspected ischemic chest pain. The secondary analysis will provide evidence to determine whether emergency physicians can be trained to measure carotid plaque height accurately when compared to the gold standard ultrasonographer measurement. Significance: If FOVUS can reliably identify very low risk patients, implementation of this novel tool could reduce ED length of stay, monitoring, and overcrowding.