View clinical trials related to Carotid Artery Plaque.
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.
A Perspective, Self-control Study on the Progression of Carotid Plaques in Anti-PD-1 mAb Treated Tumor Patients by Artery Ultrasound Follow-up
Ischemic strokes are a leading cause of death and disability worldwide. In 20% of cases they are caused by the rupture of atherosclerotic plaques in carotid arteries. Risk estimation of plaque rupture is currently suboptimal. Although pathology studies have shown that plaque composition provides a better risk assessment (lipid-rich core with thin fibrous cap = high risk (unstable plaque); fibrous core and a thick fibrous cap = low risk (stable plaque)), plaque composition cannot be determined using imaging techniques, and can therefore not be assessed non-invasively. Ultrasound, which is already widely used in clinical practice to determine plaque geometry could be an optimal technique to determine plaque composition and monitor plaques in a large population, due to its low patient burden, relatively low cost and speed of measurement. However, using conventional ultrasound it is not possible to reliably determine plaque composition. However, this might be possible using newly developed ultrasound functionalities(shear wave and strain elastography) enabling tissue stiffness estimation. It is known that recurrence risk is greatest in the first week after a stroke or transient ischemic attack (TIA) and decreases afterwards, probably due to a stabilization of the plaque due to a change in composition. Additionally, lipid-lowering medication is known to further reduce the recurrence risk after such an event, probably due to an acceleration of the stabilization process of the plaque. In this study, the investigators want to investigate whether Ultra-COMPASS ultrasound measurements (a combination of shear wave and strain elastography and ultrafast compounding (a fast variant of standard anatomical ultrasound to determine plaque geometry)) could be used to determine changes in plaque composition after a stroke / TIA. Primary objective: Investigate whether it is possible to detect plaque stabilization, determined by plaque stiffness, after a brain infarction or transient ischemic attack with Ultra-COMPASS ultrasound measurements. Secundary objectives: - Determine the association between (changes in) Ultra-COMPASS measurements and the lipid-lowering drugs used 6 and 12 weeks after ischemic stroke. - Determine the association between Ultra-COMPASS measurements and recurrent cardiovascular events (TIA / cerebral infarction / myocardial infarction/death) 6 and 12 weeks after ischemic stroke. - Determine the association between Ultra-COMPASS measurements and (changes in) low-density lipoprotein levels 6 and 12 weeks after ischemic stroke (if known). Study design: This is a prospective, longitudinal, observational, single-center cohort study in patients after a cerebral infarction or TIA with stenosis of one / both carotid arteries of 30-70% that receive or start withcholesterol-lowering medication. Ultra-COMPASS measurements will be taken within 7 days after brain infarction/TIA and at 6 ± 1 and after 12 ± 1 weeks in both carotid arteries to see if plaques stabilize overtime and to what extent medication stimulates a beneficial change in plaque composition.
the aim of this study is to determine whether an intraoperative optimization protocol using the enhanced flow-based hemodynamic parameters of the FloTrac/Vigileo device in combination with intraoperative measurement of the sublingual microcirculation with the Cytocam-IDF device would result in an improvement in outcome in high-risk patients undergoing major vascular surgery, measured by the hospital LOS in comparison with intraoperative FloTrac/Vigileo monitoring alone. The FloTrac/Vigileo device only needs standard arterial access for enhanced, flow-based hemodynamic monitoring. It is reported to be easy to use and easy to set up and calculates the stroke volume (SV) on the basis of the arterial waveform in combination with demographic data. Cardiac index (CI), stroke volume index (SVI) as an indicator for fluid status and stroke volume variation (SVV) as an indicator for fluid responsiveness during mechanical ventilation and sinus rhythm will be continuously measured during major vascular procedures, including carotid endarterectomy (CEA), open abdominal aortic aneurysm (AAA) repair , endovascular aneurysm repair (EVAR), thoracic endovascular aneurysm repair (TEVAR) and fenestrated endovascular aneurysm repair (FEVAR).
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.
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.
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.
Stroke is a major cause of death and disability worldwide. Stenotic carotid arteries can lead to stroke if the cause of the stenosis is a vulnerable atherosclerotic plaque. Recent studies reveal that if a patient has a plaque in the carotid artery it is highly probable that he/she will develop plaques in other superficial arteries like the femoral artery. Currently, duplex ultrasound is used to determine the grade of stenosis and is the main criterion for intervention (endarterectomy) planning. However, the stability, or instability of the plaque cannot be determined non-invasively. Photoacoustics is a novel, non-invasive imaging modality that uses pulsed laser light to generate laser induced ultrasound in the absorbing region of the tissue. Photoacoustic imaging provides optical contrast of biological tissue chromophores with an acoustic resolution and imaging depth, which is promising for visualization of plaque composition. The advantage of photoacoustics is the use of multiple wavelengths, since different tissues respond differently to different wavelengths. Hence, non-invasive, in vivo, morphology assessment is a future application of this new modality that would improve diagnosis and clinical decision making. The drawback is the limited penetration depth of the laser light and the signals generated by surrounding tissue. A new, integrated photoacoustic device has been developed that meets all safety requirements and has an improved penetration depth, suitable for imaging of carotid arteries with the aim to distinguish between plaques with different morphology.
While 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) imaging has been used as an early marker of drug efficacy in numerous clinical cardiovascular drug trials, as a glucose analog, its signal in the vasculature lacks inflammatory cell-specificity. Moreover, high background 18F-FDG signals from the myocardium often preclude coronary artery imaging, despite attempts to suppress myocardial tracer uptake by dietary manipulation. These limitations of 18F-FDG for measuring changes in vascular inflammation arising from drug intervention highlight important unmet needs, which might be overcome by using a somatostatin receptor subtype-2 (SST2) PET tracer.