Active clinical trials for "Carotid Artery Diseases"

Cerebral hyperperfusion syndrome (CHS) was initially described as a clinical syndrome following carotid endarterectomy (CEA), but it may present in both CEA and carotid artery stenting, and is characterised by throbbing ipsilateral frontotemporal or periorbital headache, and sometimes diffuse headache, eye and face pain, vomiting, confusion, macular oedema, and visual disturbances, focal motor seizures with frequent secondary generalisation, focal neurological deficits, and intracerebral or subarachnoid haemorrhage. Knowledge of CHS among physicians is limited. Most studies report incidences of CHS of 1-3% after carotid endarterectomy. CHS is most common in patients with increases of more than 100% in perfusion compared with baseline after carotid revascularization procedures and is rare in patients with increases in perfusion less than 100% compared with baseline. The pathophysiological mechanism of CHS remains only partially understood. The chronic lowflow state induced by severe carotid disease results in a compensatory dilation of cerebral vessels distal to the stenosis, as part of the normal autoregulatory response, to maintain adequate cerebral blood flow (CBF). In this chronically dilated state, the vessels lose their ability to autoregulate vascular resistance in response to changes in blood pressure. In fact, it has been shown that this dysautoregulation is proportional to the duration and severity of chronic hypoperfusion. After revascularization and reperfusion, the impaired cerebral autoregulation could then contribute to a cascade of intracranial microcirculatory changes, as explained above, with an inability of reaction toward the augmentation of the CBF after the carotid recanalization. Although most patients have mild symptoms and signs, progression to severe and life-threatening symptoms can occur if CHS is not recognised and treated adequately. Because CHS is a diagnosis based on several non-specific signs and symptoms, patients may be misdiagnosed as having one of the better-known causes of perioperative complications like thromboembolism.

The goal of this observational study is to learn more about plaque biology in asymptomatic carotid artery stenosis (ACAS) patients through imaging. The main questions it aims to answer are: To determine the ability of 64Cu-CANF-Comb positron emission tomography (PET) to risk stratify ACAS patients for stroke event, to include transient ischemic attack or remote ipsilateral intervention. To further understand the role of Natriuretic Peptide Receptor C (NPRC) in the evolution of carotid atherosclerosis. Participants will be asked to undergo a carotid PET-magnetic resonance imaging (MRI) examination to assess whether the carotid atherosclerosis uptake of 64Cu-CANF-Comb as measured by PET-MRI correlates with patient outcomes (stroke, transient ischemic attack, or remote ipsilateral intervention).

This is a technical development study with the goal to develop 3D techniques for atherosclerosis plaque characterization. We hypothesize that 3D MRI is superior to 2D MRI in characterizing major plaque constituents that contribute to severe clinical events such as myocardial infarction or stroke. The major advantages of the 3D techniques to be developed will include high spatial resolution, reduced scan times, and optimized image contrast. The use of contrast injection is not needed with the new techniques, which is greatly beneficial for patients with advanced chronic kidney disease.This is not a funded clinical trial.

NOR-SYS is a clinical research program about young ischemic stroke patients from 15 to 60 years. Patients, partners and the couple´s adult children who are at least 18 years old, are all invited to ultrasound examinations due to a standardized protocol. Parents of patients and partners are invited to return their answers of standardized questionnaires about clinical ischemic events such as stroke, angina or myocardial infarction or peripheral artery disease. Study inclusion time of patients and their families is 5 years. A biobank is build from samples from patients, partners and adult children. Clinical follow-ups for patients and partners are planned after 5, 10 and 15 years. Clinical follow-ups for adult children are planned after 10 and 20 years. Hypotheses: What do patients know about their parents clinical ischemic events? How much established pathology in arteries do we find by a standardized ultrasound protocol at the time of ischemic stroke at a young age? Differences concerning risk factors and ultrasound findings between patients and partners? Differences between children from families with several ischemic events among parents and grandparents vs. children from families without ischemic events? Biochemical markers related to ultrasound findings and artery disease.

The purpose of this research is assess imaging and identification of soft plaque that undergoes large deformations or strain will identify plaque vulnerable to rupture which could lead to 'silent strokes'. Validation of current study results with MRI will foster use of real-time ultrasound (US) strain imaging and strain indices as a screening tool for identifying normal human participants susceptible to increased vascular aging and developing plaque prone to rupture or micro-embolization. Current research will evaluate Lagrangian carotid strain imaging (LCSI) for prediction of vascular health on volunteers. In this study, investigators will evaluate age-related strain variations (due to plaque deposition) in the carotid artery, establishing groundwork that will help identify typical and atypical values for these indices. Investigator's hypothesis is that plaques with higher strain indices (softer plaques) are more prone to rupture than plaques with lower strain indices (stiffer) plaques, thus requiring intervention. Clinical criteria for treatment has focused primarily on the degree of stenosis. Long-term objectives are to provide non-invasive methods for screening participants at risk for vascular aging or plaque rupture in asymptomatic participants, expanding upon current criteria for risk assessments based on focal transient ischemic attack (TIA) or strokes. Variations in vessel strain have been associated with, or are precursors to, plaque deposition, vascular aging, or cerebrovascular diseases. Increased arterial strain and pressure changes have been linked to brain aging using magnetic resonance imaging (MRI) based vascular indices, and memory deficits commonly linked to Alzheimer dementia. Stiffening and thickening of the arterial walls have also been associated with cerebrovascular disease. Investigators hypothesize that strain indices as vascular biomarkers can be utilized for screening possible 'vulnerable participants' validated with MRI, with the potential ability to improve endothelial function and reverse vascular aging. Strain indices may enable differentiating study participants with vascular cognitive impairment (VCI) from other dementias. Cognitive testing is unable to make this differentiation.

The root cause of heart attacks and strokes is atherosclerosis, the hardening and thickening of blood vessels due to the presence of "plaque" which is a build-up of fat and cholesterol in the walls of vessels. To diagnose heart disease, patients receive a stress test to find out if they require surgery. Up to 52% of patients receiving an angiogram (surgery) to look at plaque blockages in the heart are found to be normal (no blockage). Patients who are suspected of having heart disease often undergo a stress test, which helps cardiologists decide if the patient has heart disease, but stress tests can give false results. In Ontario alone, 90% are stress tests are found to be normal and patients are sent home with little follow-up. Of these 3-5% (~4,000 patients/year) will have a major cardiovascular event (heart attack, surgery, or death) within 3 years. We need to improve the stress test accuracy to reduce cardiac outcome. We now know that it is not just the total amount of plaque that leads to heart attacks and strokes, but the composition of the plaque that can lead to breakage causing a heart attack. Plaques are soft and fragile, and typically contain fat and small leaky blood vessels within their cores. If we are able to identify patients that have leaky plaques using ultrasound, we may be able to improve the accuracy of stress testing. We propose a study looking at the combination of stress testing (assessing heart function) and neck ultrasound (assessing plaque composition), to identify patients at risk for cardiovascular events (heart attacks and death). We will enrol patients from 6 sites across Canada and follow-them for cardiac outcome for 3 years.

SSPC includes degree of Stenosis, Symptoms, Plaque stability and Compensation of the cerebral blood flow. SSPC, a comprehensive evaluation system on carotid artery stenosis, is established and advocated in this trial in order to make assessment on risk of carotid revascularization preoperatively and prediction of cerebral events postoperatively.

The hypothesis of this study is that neural regulations of the atherosclerotic plaque, identified in the murine model of atherosclerosis, could also exist in human pathology. The dysregulation status of the autonomic nervous system is typical of several cardiovascular diseases, but the role it exerts in the modulation of important mechanisms at the basis of the atherosclerotic process progression has not been investigated yet. The main aim of this study will be to investigate, in the atherosclerotic plaque, the alterations of inflammatory and immune processes, the neural modulations and the presence of dysregulations of the autophagic process. The investigators will also associate the potential presence of neural modulations of the plaque to its stability/instability, from a clinical-translational point of view. Finally, the investigators aim at providing a solid basis for the development of novel therapeutic strategies, which could reduce the elevated health and welfare costs for the clinical management of cardiovascular pathologies such as atherosclerosis.

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.

The goal of this clinical trail is to compare the differences in carotid plaque Treg cells' gene signature for activation, proliferation, and suppressive function using scRNA-seq in patients treated with IL-2 compared to control.