View clinical trials related to Carotid Stenosis.
Filter by:Background: Cerebral hyperperfusion syndrome (CHS) is a life threatening complication of carotid endarterectomy (CEA) and the changes of middle cerebral artery velocity are used to predict the occurrence of CHS but the accuracy is limited. In addition, changes of BP post-operatively comparing with baseline BP should be a predictive factor of CHS. Objective: The investigators aimed to create a predictive index, velocity systolic blood pressure index (VSI), for improving the predictive power of Transcranial Doppler monitoring regarding CHS. Methods: The study design is a diagnostic test, which is an observational analytic clinical study. From March 2013 to September 2014, 200 patients will be recruited. Patients will be classified according to the CHS occurrence. VSI combined the changes of middle cerebral artery velocity and blood pressure crossing CEA and the intra- and post-operative increase ratios of middle cerebral artery velocity were calculated. Their prediction power of CHS will be compared. Sensitivity, specificity, positive predictive value, negative predictive value of them will be calculated. Receiver operating characteristic analysis will be performed. Expected Outcomes: Comparing with the commonly used intra-operative and post-operative TCD monitoring, VSI may be more useful to select CHS in patients who underwent CEA. As far as the investigators know, analysis or studies combining the BP and velocity changes in the prediction of CHS have never been performed.
Atherosclerosis is a chronic, systemic and progressive disease affecting different arterial blood vessels in the body. Atherosclerotic lesions silently progress from small plaques to severe stenosis and may remain asymptomatic for years. Unstable plaques and stenosis (also called vulnerable plaques), however, are prone to rupture leading to myocardial infarction, or stroke. The proliferation of the small arteries that are distributed to the outer and middle coats of the larger blood vessels (vasa vasorum) and within the atherosclerotic plaques (neovascularization) are inherently linked with the atherosclerotic plaque development, plaque inflammation and vulnerability. By injecting ultrasound contrast agents (microbubbles) into the blood stream, it is possible to detect this microcirculation of the vessel wall and the neovascularization within the atherosclerotic plaque using a contrast-enhanced ultrasound (CEUS) imaging technique. Particularly, CEUS of the carotid artery has been introduced as a non-invasive technique to improve detection of carotid atherosclerosis and to evaluate the presence of carotid plaque neovascularization which has emerged as a new marker for plaque vulnerability. The project investigates the predictive value of the detection of carotid plaque neovascularization on CEUS imaging in patients with asymptomatic carotid artery stenosis regarding the progression of the carotid atherosclerotic lesion and future vascular events including myocardial infarction, stroke or vascular intervention. The investigators hypothesize that neovascularization within the carotid lesion will significantly be more pronounced in patients with progressive carotid lesions and in patients suffering future vascular events during. The project will support the concept that intraplaque neovascularization is associated with plaque instability and vulnerability and therefore, the use of CEUS may provide an additional non-invasive, simple, safe, and reliable imaging modality to risk stratify individuals. The identification of vulnerable that are at increased risk of rupture by identification of intraplaque neovascularization is expected to improve the prediction of future vascular events and thus allow for better treatment selection. It will help the clinician to further risk stratify carotid stenosis. Particularly, it will help to identify unstable carotid stenosis that may already benefit from invasive therapy as carotid thromboendarterectomy and stenting.
Microembolization is commonly associated with carotid artery stenting (CAS), but our understanding of subclinical microembolization is superficial. Through collaborative effects of multidisciplinary team-experts, novel approaches, and longitudinal evaluations, we hope to better understand the clinical significance and long-term cognitive effects of microemboli. This proposal may change our current clinical practice by providing a better outcome measure for carotid interventions and improving outcomes of CAS procedures through risk factor stratification. Our central hypothesis is that development of subclinical microemboli is associated with decline in cognitive function following CAS and that the risk of development of microemboli themselves is associated with patient- and procedure-related factors. We hope that this prospective study will help to clarify these important issues in the era of rapidly evolving percutaneous interventions.
Remote limb ischemic preconditioning (RIPC) has neuro-protective and anti-inflammatory effects on ischemia- reperfusion injury. As the extent of its effect is unknown, the investigators will use clinical outcome, serum biochemical markers and brain magnetic resonance imaging (MRI) to determine whether RIPC has neuro-protective and anti-inflammatory effects on patients undergoing carotid artery stenting.
Patients suffering from symptomatic carotid artery stenosis, transient ischemic attacks (TIAs), amaurosis fugax or stroke receive either Revacept (single dose) plus antiplatelet monotherapy or monotherapy alone. Patients receive a single dose of trial medication by intravenous infusion for 20 minutes. Patients are followed up one and three days after treatment, at 3 months and by a telephone interview at 12 months.
The aim of this study is to develop non-invasive MRI, and MRS approaches that will quantify the plaque composition and lipid content of plaques and will have the potential for repeated in vivo measurements. To investigate sensitivity and specificity of 3.0 Tesla MRI and MRS for dimension and composition assessment of carotid artery plaques, in particularly those plaques with lipid rich necrotic cores. This non-invasive cross-sectional study, compares carotid parameters of in-vivo 3.0 Tesla MRI, MRS and B-mode ultrasound with histology specimens collected at endarterectomy.
This trial will be the first trial for the Investigation Product (IP), [F-18]RGD-K5 for carotid plaque imaging and will be conducted as a Phase II trial since this compound has already been tested in humans for phase I and phase II imaging. All study results will be evaluated and analyzed in order to consider the design for future clinical trials.
The purpose of the study is to test a new amplified stethoscope(AudioDoc) that can detect the presence of bruit by using an acoustic signal to represent the bruit. This pilot study will address two questions: is there a detectable difference in recorded sound signal of carotid and femoral bruit when compared to sound signals captured when there is no bruit present; is the use of a visual recorded signal more accurate in identifying carotid and femoral bruit when compared to traditional auscultation with a regular stethoscope and ultrasound.
The aim of the project is to demonstrate a fibrinolytic effect of sonothrombolysis (continual transcranial Doppler monitoring) using 2 MHz diagnostic probe on the reduction of risk of brain infarctions due to the activation of endogenous fibrinolytic system during carotid endarterectomy (CEA) and carotid stenting (CS). 240 patients indicated for CEA (120 patients) and CS (120 patients) will be enrolled into the study in order to demonstrate a twenty-percent risk reduction of number and volume of brain infarctions detected using MRI examination 24 hours after CEA or CS in 5% level of significance. Patients will be randomized - subgroup 1 will undergo a 60minute non-diagnostic TCD monitoring during CEA or CS, subgroup 2 will undergo interventions without TCD monitoring. The second aim is to compare number of brain infarctions detected using MRI between CEA and CS patients. Confirmation of the investigators hypothesis that sonothrombolysis is able to activate endogenous fibrinolytic system during CEA or CS with consecutive reduction of the number and volume of brain infarcts, can lead to the increase of the safety of CEA and CS in patients with internal carotid artery stenosis. The investigators can presume that up to 50% of patients indicated for CEA or CS can be treated using these methods in the future. In the Substudy "Risk of brain infarction after carotid endarterectomy and stenting" the the risk of asymptomatic and symptomatic brain infarctions, changes in cognitive functions, as well as morbidity and mortality at 30 days between patients with symptomatic and asymptomatic severe ICA stenoses undergoing elective CEA and CAS will be compared. The sample size of the Substudy was based on an expected 80% difference of new ischemic lesions on DWI-MRI between CEA (estimated prevalence, 30%) and CAS (54%). Pre-study calculations showed that a minimum of 73 patients in each group was needed to reach a significant difference with an alpha value of 0.05 (two-tailed) and a beta value of 0.8 assuming that 15% of subjects would be lost to follow-up or refuse to participate in the study.
The purpose of this study is to evaluate the efficacy and safety of two different loading doses of Clopidogrel and a reloading of Atorvastatin in the prevention of periprocedural ischemic brain damage in patients undergoing carotid angioplasty.