View clinical trials related to Carotid Stenosis.
Filter by:Diabetes in an independent risk factor for ischemic stroke, whose associated mortality rate is higher and sequelae more serious than for nondiabetics. Diabetes increases the risk of stroke or death after surgical carotid revascularization or endoluminal angioplasty. It is, with contralateral ICA occlusion, 1 of the 7 factors doubling the stroke risk after carotid endarterectomy. Diabetes also enhances the cerebral hemorrhage risk associated with carotid surgery, thrombectomy or thrombolysis revascularization of the cerebral arteries. This study was undertaken to examine whether the hemodynamic cerebral ischemia (HCI) frequency, which increases stroke severity, is higher in diabetics than nondiabetics and, if diabetes carries an excess HCI risk, whether it is independent of contralateral ICA occlusion.
Previous studies did not reach a consensus on the influence of the type of anesthesiologic procedure and monitoring, during carotid thrombendarterectomy, on perioperative complications and cognitive outcomes. The aim of this study is the optimization of brain perfusion during the vascular carotid clamp using multimodal monitoring. We assume that standardized monitoring techniques and a better selection of cognitive tests will allow a more accurate assessment of subclinical cognitive deficits.
In this study, we investigated the effect of the capacity to cope with oxidative stress (oxidative stress response during and after clamping) in individuals with cerebral oximetry level between 40- 60 % and above 60 % and their effect on cognitive functions. Methods: In this retrospective study, patients who were scheduled for carotid endarterectomy, examined the MOCA tests before and after the operation and collected blood samples intraoperatively were included between January 2020-2021. The time periods specified below, blood samples were taken and serums were frozen at -80 celcius all this patients. Montreal cognitive function assessment test was applied before the operation, 24 hours and 7 days after the operation. Ten mililiters venous blood samples were collected to examine the status of basal neuron specific enolase, S100B, oxydative stress parameters (HAF-1 and DAF-1) at time intervals. Time intervals as follow: T1: Peripheral baseline measurements (blood will be taken from arterial blood sampling) + Cerebral Oxymeter levels + Montreal cognitive performance test + Modified Rankin Scale (mRS) T2: 1 minute before clamping (from peripheral and jugular vena blood sampling) + Cerebral Oxymeter levels T3: Before opening clamp(from peripheral and jugular vena blood sampling) + Cerebral Oxymeter levels T4: 24 hours after the procedure. (peripheral blood sampling) + Montreal cognitive performance test T5: 7 days after the operation. (peripheral blood sampling) + Montreal cognitive performance test + CO levels+ Modified Rankin Scale (mRS) Results: We found significantly positive corelation between cerebral oxymeter levels, oxydative stress parameters and cognitive performance tests in this six patient.
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.
There is a wealth of evidence implicating the important role of blood flow throughout all stages of the process of atherogenesis. Two locations along the vascular tree at which atherosclerotic plaques are typically found are the carotid artery (CA) and the superficial femoral artery (SFA). Nowadays, ultrasound is the technique of choice for assessing the vascular condition in the CA and SFA. However, clinically used ultrasound techniques show a large variability in estimating the blood flow velocity, due to multiple limitations. With the advent of ultrafast ultrasound imaging, (almost) all elements of the transducer can be activated simultaneously. These so-called plane wave acquisition acquires thousands of images per second and makes continuous tracking of blood flow velocities in all directions in the field of view possible. This high-frame-rate acquisition opened up new possibilities for blood flow imaging at the CA and SFA, such as blood Speckle Tracking (bST) and ultrasound Particle Image Velocimetry (echoPIV). Both these vector flow imaging (VFI) techniques enable the quantification of 2D blood flow velocity profiles, where bST uses no contrast agents compared to echoPIV. Beside these novel ultrasound based techniques, 4D Phase Contrast Magnetic Resonance Imaging (4D flow MRI) enables a non-invasive quantification of the 4D blood flow velocity profiles (3D + time) and can be used as reference standard for blood flow assessments in-vivo. We therefore aim to evaluate the performance of both VFI techniques in comparison to 4D flow MRI measurements in the CA and SFA of healthy volunteers.
Cerebral circulation time in patients with severe carotid artery stenosis was found to be associated with hyperperfusion syndrome. Remote ischemic preconditioning can change the ability of cerebral autoregulation. The prospective, randomized controlled, blind outcome evaluation, multi-center study aimed to investigate the effect of remote ischemic preconditioning on cerebral circulation time in patients with severe carotid artery stenosis.
Internal carotid artery (ICA) is intended to supply blood to brain. The carotid bulb located upstream of ICA origin is prone to atherosclerosis. This is an accumulation of fat and calcium in the wall forming a plaque that gradually thickens and leads to carotid stenosis (CS), which causes a decrease in blood flow. The risk of CS is stroke caused either by carotid artery thrombosis (occlusion) or by atherosclerotic plaque fragmentation, some components of which may leak into the brain (embolism). When diagnosing CS, an Echo-Doppler is performed to determine bulb and ICA origin obstruction rates. The reference method of quantifying CS is based on hemodynamic criteria that only allow the diagnosis of high grade stenosis thresholds (50%-70%). Below 50%, low-grade stenosis, patient follow-up is limited and could be based on morphological criteria; ultrasound imaging being a reference technique for human body structures morphological assessment, especially vessels. Two methods of CS morphological quantification with Doppler ultrasound currently exist. Calibre reduction at the maximum of stenosis can be measured by relating the smallest luminal diameter to the vessel diameter at stenosis site (ECST method) or to the downstream ICA diameter (NASCET method). As bulb diameter measures ≈1.8 times that of ICA, ECST appears to be more suitable for CS quantification. For high-grade stenosis, morphological quantification performance is impaired due to extensive calcification of large atheromatous plaques. However, it is possible that less calcified nature of low-grade stenosis and the use of a rigorous methodology will allow reproducible assessment in routine practice. This technique has not yet been evaluated, although it is a frequent situation in patient follow-up.
The objective of this clinical investigation is to evaluate the safety and technical success of the Basecamp Vascular controllable directional GECKO guidewire when used to facilitate endovascular access to the targeted vessel in order to treat the vascular lesion.
Ischaemic stroke is attributable to thromboembolism caused by carotid atherosclerotic disease in 18-25% of patients. Guidelines for prevention of stroke (especially carotid endarterectomy) in patients with carotid atherosclerotic plaque are based on the quantification of the degree of stenosis. The hyoid bone, in proximity to the carotid artery, has been implicated in the pathophysiology of carotid artery dissection, atherosclerotic carotid disease, and compressive syndromes. In atherosclerotic carotid disease, pressure on the carotid artery induced by these bone structures has been proposed to play a possible role in plaque formation and rupture, leading to stenosis, occlusion, or artery-to-artery embolism. In a recent ultrasound study, dynamic displacement of the carotid artery with interference of the hyoid bone during swallowing, named as "flip-flop" phenomenon (FFP) has been associated with carotid artery stenosis and stenosis-related stroke. Another study based on CTA assessment observed no association between hyoid-carotid distance and plaque thickness, stenosis, or progression of thickness/stenosis. In that study, in almost two-third of the patients CTA was performed for stroke/transient ischemic attack work-up, including a vast majority of patients with absence of carotid stenosis (median degree of carotid stenosis was 7%), and plaque-related stroke was not assessed. The objective of this study is to determine the anatomic hyoid-carotid interaction (ie, hyoid-carotid distance, carotid position relative to the hyoid bone, and hyoid morphology) based on CTA and its relation to the degree of carotid stenosis and stenosis-related stroke.
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.