Active clinical trials for "Carotid Artery Diseases"

To evaluate subclinical atherosclerotic disease in menopausal women.

Atherosclerosis of the carotid arteries is a common cause of stroke. The prevalence and progression of carotid atherosclerosis are believed to be influenced by genetically inherited variations in lipoprotein metabolism. This study investigates the specific role of paraoxonase, an enzyme thought to detoxify atherogenic oxidized low-density lipoprotein. This study compares veterans who have significant carotid atherosclerosis on ultrasound examination with controls without carotid atherosclerosis. Both paraoxonase activity and genotype will be determined and compared between groups. The results may eventually make it possible to screen for a paraoxonase allele that confers high risk of atherosclerosis, and to diminish the risk by early treatment.

To better understand the excess cardiovascular disease associated with diabetes mellitus.

As of today, no suitable multiparametric predictive method is available to properly estimate stroke risk in patients with carotid artery stenosis. Carotid artery stenosis is one of the proven risk factors of stroke incidence, but the indication of its intervention is merely the grade of stenosis itself. The current international guidelines suggest intervention for asymptomatic patients only with potentially high risk plaques but pharmacological treatment is advised to low risk patients. Unfortunately there is no proven and widely accepted system to distinguish these two categories of patients with carotid artery stenosis. In this project the following parameters will be assessed both in asymptomatic and symptomatic patients: 1, preoperative stroke risk prediction based on comparative analysis of CT angiography (CTA) results of plaque morphology and ultrasound (US) based plaque elastography analysis, 2) intracranial bloodflow will be measured by transcranial Doppler sonography(TCD), 3) presence recent of silent brain ischemia on diffusion weighted imaging (DWI) MR (magnetic resonance), 4) retinal perfusion measurement by optical coherence tomography angiography (OCT). The investigators aim to establish a clinically meaningful and more accurate (than stenosis grade) stroke risk prediction algorithm for asymptomatic carotid stenosis patients based on these parameters.

Major vascular surgery involves operations to repair swollen blood vessels, clear debris from blocked arteries or bypass blocked blood vessels. Patients with these problems are a high-risk surgical group as they have generalized blood vessel disease. These puts them at risk of major complications around the time of surgery such as heart attacks , strokes and death. The mortality following repair of a swollen main artery in the abdomen is about 1 in 20. This contrasts poorly with the 1 per 100 risk of death following a heart bypass. Simple and cost-effective methods are needed to reduce the risks of major vascular surgery. Remote ischaemic preconditioning (RIPC) may be such a technique. To induce RIPC, the blood supply to muscle in the patient's arm is interrupted for about 5 minutes. It is then restored for a further five minutes. This cycle is repeated three more times. The blood supply is interrupted simply by inflating a blood pressure cuff to maximum pressure. This repeated brief interruption of the muscular blood supply sends signals to critical organs such as the brain and heart, which are rendered temporarily resistant to damage from reduced blood supply. Several small randomized clinical trials in patients undergoing different types of major vascular surgery have demonstrated a potential benefit. This large, multi-centre trial aims to determine whether RIPC can reduce complications in routine practice.

The relationship of the natural history of atherosclerosis between different vascular beds has not been well characterized. Determination and comparison of the relative rates of progression and extents of atherosclerosis in the coronary and carotid arterial trees may have major impacts on clinical research and clinical practice. Correlation between findings in the carotid and coronary circulations is an important scientific and clinical topic to address. Results from a well design study incorporating imaging technologies that currently represent the gold standards for the assessment of coronary and carotid artery plaque burden, will have potentially impact on clinical research and clinical practice.

Clopidogrel besylate (CB) is not differentiated relative to the orignal clopidogrel hydrogen sulfate (CHS) in the pharmacokinetics and in antiplatelet potency in healthy volunteers. In addition,CB exhibits similar pharmacodynamic properties compared to CHS in patients with a history of acute coronary syndrome (ACS) and in patients with ACS undergoing percutaneous coronary intervention (PCI). However, there is a lack of data on the clinical efficacy and safety of this salt to the original salt in patients with cardiovascular disease. The aim of this study is to investigate the clinical efficacy and safety of CB in relation to that of CHS in patients eligible to receive clopidogrel.

Heart attacks and strokes caused by the unstable atherosclerotic plaques remain the leading cause of death in the United States. Unstable plaques often have more fat than stable plaques. This study will investigate if a treatment with LDL-lowering plus HDL-raising compared with LDL-lowering alone would more effectively reduce the plaque fat content assessed by magnetic resonance imaging (MRI), therefore, further reducing heart attacks and strokes.

The aim of the present study is to examine the atherosclerotic plaque stability using in vivo and in vitro techniques and to investigate the influence of exercise, anti-diabetic, lipid-lowering and cannabinoids receptor antagonists on atherosclerotic plaque texture in patients with cardiovascular risk and animals prone to atherosclerosis.

The purpose of this study is to determine how well patients undergoing carotid endarterectomy will perform on a battery of tests to assess brain function before and after surgery as compared to a control group of patients undergoing spine surgery. This study will serve to: (a) determine incidence of neurologic/neuropsychometric change in patients undergoing carotid artery surgery, and (b) to ascertain the time it takes for these changes to resolve.