Active clinical trials for "Carotid Stenosis"

Uni-Graft® K DV Patch is marketed in Europe since 1999 for reconstructive interventions of the deep femoral, femoral and iliac artery and was also indicated for carotid interventions until 01/2020. Previous studies focused on the clinical performance of different patch materials used for patch angioplasty in different indications, without specifying the product or manufacturer. Thus, it is not surprising that there is a limited amount of published literature available describing the use of the Uni-Graft® K DV Patch in the clinical routine. Therefore, the aim of the present non-interventional study (NIS) is to close this gap by collecting and evaluating existing safety and performance data documented in the clinical routine especially during the application of the Uni-Graft® K DV Patch.

Carotid artery stenting (CAS) is one of major treatments in prevention of ischemic stroke. Because of sinus reflex due to stenting and balloon dilatation, persistent post-surgery hypotension is a common perioperative event. Persistent hypotension can lead to perioperative adverse events like ischemic stroke, myocardial infraction, renal failure and death; or more usually, it prolongs length of stay and hospital expenses. Renin-angiotensin-aldosterone inhibitor (RASI) could inhibit the release of catecholamine and may lead to higher rate of persistent hypotension after CAS compared to other hypertensives.Thus, the investigators aim to investigate the effect of pre-operation antihypertensive drugs on persistent hypotension after stenting, and followed burden in carotid artery stenting comorbid with hypertension patients.

The retinal vessels have been shown to reflect vascular changes inherent to systemic pathologies, even when no ocular disease is identified. As such, the eye's vasculature is ableto serve as a window to the vascular health of the human body and a means of assessing systemic endothelial function. Optical coherence tomography angiography (OCTA) employs optical means to image all the retinal vascular layers and the choroid, providing an extremely detailed image of the microvascular network in a fast, reproducible and totally non-invasive way. As such, it is currently the best non-invasive way of having an image of human capillaries. Recently, OCTA has been used to study the retinal vessels' structure and function in several cardiovascular diseases. As an example of its predictive potential, reduced retinal microvascular density has been associated with the cardiovascular risk profile in patients admitted to the hospital for an acute coronary syndrome. Recent studies have also shown the retinal microvasculature density to be reduced in patients with carotid artery disease (CAD), namely carotid stenosis, and that endarterectomy increases retinal flow and vessel density.

The purpose of this study is to create a state-wide biorepository and resource center for cerebrovascular diseases in Florida, which will include collecting medical history information and blood from families affected by cerebrovascular disease. The information and blood samples collected may be used in future research for the study of cerebrovascular disease and to learn about, prevent or treat other health problems.

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.

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 purpose of this study is to build upon trials done over 30 years ago, which did not include statins, new antiplatelet agents, and newer antihypertensive medications. Since the landmark trials (NASCET, ECST), there have been new developments in medical stroke prevention, which creates a gap in knowledge. The aim of this study is to evaluate that clinical care with Intensive Medical Therapy (IMT) alone, the one year stroke rate in patients with symptomatic carotid stenosis and low risk clinical features will be <5%.

Background: Large vessel carotid stenosis represent significant cause of ischaemic stroke. Indication for surgical revascularisation treatment relies on severity stenosis and clinical symptoms. Mild clinical symptoms such as transient ischemic attack, amaurosis fugax or minor stroke preceded large strokes in only 15% of cases. Aim: The aim of this prospective study is to evaluate whether retinal perfusion is impacted in significant carotid stenosis. Automated retinal oximetry could be used to better evaluate perfusion in post-stenotic basin. The investigators presume the more stenotic blood vessel, the more reduced retinal perfusion is resulting in adaptive changes such as higher arteriovenous saturation difference due to greater oxygen extraction. This could help broaden the indication spectrum for revascularisation treatment for carotid stenosis. Methods: The investigators plan to enroll 50 patients a year with significant carotid stenosis and cross-examine them with retinal oximetry. Study group will provide both stenotic vessels and non-stenotic vessels forming the control group. Patients with significant carotid stenosis will undergo an MRI examination to determine the presence of asymptomatic recent ischaemic lesions in the stenotic basin, and the correlation to oximetry parameters. Statistics: Correlation between the severity of stenosis and retinal oximetry parameters will be compared to the control group of non-stenotic sides with threshold of 70%, respectively 80% and 90% stenosis. Data will be statistically evaluated at the 5% level of statistical significance. Results will be then reevaluated with emphasis on MRI findings in the carotid basin. Conclusion: This prospective case control study protocol wil be used to launch a trial assessing the relationship between significant carotid stenosis and retinal perfusion measured via automated retinal oximetry.

Researchers are collecting information and blood from subjects undergoing carotid artery interventions.

The goal of this observational study is to learn about how to utilize multiple evaluation techniques in carotid artery stenosis patients for optimizing assessment of diagnosis and treatment strategy. The main questions it aims to answer are: Identify best strategy that use multi-modal MRI and CT to assess patients' cerebral lesions and perfusion. Identify best strategy that use multi-modal MRI, PET-MRI ultrasound and CT to assess components and characters of patients' carotid plaques. Participants will accept imaging examination before and after surgery. And doctors will collect basic characteristics, imaging results and biological samples of patients for analysis.