View clinical trials related to Constriction, Pathologic.
Filter by:Rationale: Approximately 15-20% of strokes originates from an atherosclerotic plaque rupture in the carotid artery. To reduce the risk of stroke, patients should be evaluated for possible carotid endarterectomy (CEA), which is based on simple geometrical and clinical measures. Multiple studies have shown that the current risk stratification may lead to both over- and under-treatment for patients with carotid artery stenosis. This implicates that the current guidelines are lacking patient-specific parameters and have limited sensitivity. There is a wealth of evidence implicating the important role of local (disturbed) blood flow throughout the onset and progression of atherosclerosis. Novel flow-related measures, that go beyond simple geometrical indications, are required to improve diagnosis and treatment in patients with carotid artery stenosis. Nowadays, ultrasound (US) is one of the main techniques to assess for the presence and extent of carotid artery stenosis. However, current clinically-used US systems are unable to acquire and visualize the complex flow phenomena that play such a crucial role in the atherosclerotic disease process. With the advent of ultrafast ultrasound imaging, acquiring thousands of images per second, continuous tracking of flow in all directions became feasible, which enables us to image two-dimensional blood flow and possible disturbances with high accuracy and precision. In this project, we aim to assess whether flow (related) parameters are associated with disease progression (and if so, which), in order to map the progression of atherosclerotic plaques using non-invasive, US-based blood flow imaging. In the future, this could improve risk stratification for individual patients for surgery, decrease patient mortality and morbidity, and therefore reduce healthcare costs. Objective: To longitudinally assess the association between spatio-temporal blood flow velocities (peak systole and end-diastole at common carotid artery, maximum stenosis and internal carotid artery) and the progression of carotid atherosclerosis defined by duplex measurements. Secondary objectives are to investigate the association between blood flow-derived parameters, including wall shear stress (WSS), vector complexity and vorticity, and the progression of atherosclerosis defined by duplex measurements. Furthermore, to assess the association between spatio-temporal blood flow velocities and blood flow-derived parameters (WSS, vector complexity and vorticity) and the progression of atherosclerosis as measured using ultrasound-based strain imaging.
This is a monocentric randomized prospective trial comparing 2 different endovascular strategies of intracranial arterial angioplasty in case of refractory intracranial arterial vasospastic stenosis : - chemical angioplasty - chemical and mechanical angioplasty
The investigators plan to collect 30 participants with internal carotid artery stenosis to observed the relationship between the degree of internal carotid artery stenosis and fundus vessels (and blood flow)density before operation, and compared with participants without internal carotid artery stenosis.The fundus blood flow density will be observed after intervention operation in order to see whether the operation is effective to improve the density of fundus vessels and blood flow or not.
The SIBERIA study demonstrated a clear advantage of CGuard stent implantation over the existing classical stent when using a distal anti-embolic device. At the same time, there is no Level 1 evidence for a difference between the proximal and distal anti-embolic device for the CGuard stent.
Aortic stenosis (AS) is characterised by left ventricular (LV) hypertrophy and altered myocardial substrate metabolism. Peroxisome proliferator-activated receptor (PPARα), a regulator of lipid metabolism is deactivated in pressure overload hypertrophy such as in AS and can lead to dysregulation of fatty acid oxidation, myocardial triglyceride accumulation (steatosis) and lipotoxicity. The investigators propose a proof-of-concept study to investigate the effect of altering myocardial triglyceride (MTG) using a PPARα agonist, fenofibrate on cardiac physiology in patients with asymptomatic moderate-severe AS. The primary endpoint is a change in MTG assessed by magnetic resonance spectroscopy at baseline and after 6 months of treatment. Exploratory endpoints are changes in cardiac physiology including myocardial deformation (strain) as assessed by cardiac magnetic resonance imaging. The investigators hypothesise that pharmacological reduction of MTG with a PPARα agonist will result in steatosis regression and changes in cardiac physiology.
COPAS pilot is a pilot single center double blinded randomized study to determine the effect of targeted anti-inflammation therapy using colchicine, on valvular calcification activity using imaging, i.e. aortic valvular NaF uptake. The current proposal uses a randomized design to evaluate the effect of colchicine vs. placebo on valvular calcification activity over 6 months measured using NaF PET
The CAS study is a prospective observational cohort study investigating the effects of congenital aortic stenosis (ConAoS) on the left ventricular function and the prevalence, pattern and expanse of left ventricular hypertrophy (LVH), myocardial stiffness and myocardial fibrosis.
Physiology-based decision-making about the need for revascularisation in patients with stable coronary heart disease has consistently proven better clinical outcomes than a merely anatomical approach. However, against the current recommendations, revascularisation in most of patients with chronic coronary syndromes still relies on coronary angiography alone. The increase in costs and in procedural complexity of wire-based physiology may explain the latter. Therefore, a novel non-invasive functional quantitative flow ratio (QFR) index was created in order to solve it. A retrospective and multicentre study is performed to assess the 5-year prognosis of patients undergoing coronary angiography through a centralized QFR analysis. Consecutive participants with confirmed or suspected diagnosis of stable coronary disease who underwent a coronary angiography between 01/01/2015 and 12/31/2015 were included. Aims of the study: - To evaluate the prognosis of stable coronary disease depending on the functional assessment of coronary artery disease. - To determine the % of percutaneous coronary interventions that could be avoided if this study had been carried out through functional assessment of coronary artery disease based on 3-dimensional vessel reconstruction.
TRACE-IMPAIR is a prospective, clinical study of consecutive patients that evaluates the relationship between heart failure (HF) and cognitive impairment in relation to carotid and cerebral flow. The carotid and cerebral flow will be assessed using Doppler ultrasonography, and cognitive function will be estimated during routine neuropsychological tests. It is an observational, three(natural)-group, single-center study. It is also an Academic Registry - the scientific activity of the Faculty of Medicine, Collegium Medicum, Jagiellonian University, and John Paul II Hospital.
A prospective, Multi-center, Randomized Study designed to evaluate the acute lumen gain and device procedural success of the DK ScoreTM Scoring balloon versus NSE Scoring Balloon for patients with coronary arteries stenosis.