Active clinical trials for "Carotid Stenosis"

The investigators hypothesize that inflammation in carotid plaque is predictive of the extent of ischemic lesion burden on the brain and will add to risk stratification for individuals with carotid disease.

Pilot study of early versus delayed carotid endarterectomy (CEA) for small to medium-sized ischemic stroke caused by high-grade carotid stenosis.

This research study will compare the impact of dietary restriction pre-operatively before carotid endarterectomy compared to the standard nutrition that a patient typically eats. The investigators want to find out how patients comply and generally how well patients do with this type of dietary restriction before their surgery since animal studies suggest that short - term dietary restriction may be beneficial before surgery.

Background. Carotid artery stenting (CAS) recently has become an accepted method for treatment of patients with high-grade carotid artery stenosis, who are at an increased risk for surgical carotid endarterectomy (CEA). The reported rates of neurological complications of CAS substantially decreased during the past years, and the routine use of cerebral protection devices and low profile catheter systems have further increased the procedure´s safety. In the early 90's large surgical trials in North America and Europe (NASCET, ECST and ACAS) demonstrated superiority of CEA compared to best medical treatment for symptomatic and asymptomatic patients. Provided that the ongoing randomized controlled trials comparing CAS and CEA confirm equivalence between the these methods, CAS similar to CEA is applicable to symptomatic and asymptomatic patients with high grade carotid stenosis. However, particularly in asymptomatic patients, the indication for revascularisation remains debatable. Protected CAS is associated with a very low rate of neurological complications, which are below the AHA recommendation for treating asymptomatic patients (3%). However, the introduction of new vascular protective medications like statins and clopidogrel during the recent years substantially improved the spectrum of best medical treatment, and the findings of NASCET, ECST and ACAS with respect to best medical treatment may therefore not be applicable any more. Study hypothesis and aims. Given the low frequency of spontaneous neurological complications, the preferable therapeutic approach to patients with asymptomatic high grade ( > 80%) carotid artery stenoses is currently unknown. Modern best medical treatment may manage to stabilize the atherosclerotic plaque, while CAS has the potential of resolving the carotid stenosis. Comparative data, however, are not available as yet. We hypothesized that protected CAS has a beneficial effect on occurrence of ipsilateral neurological complications and major adverse cardiac events in high-risk patients with asymptomatic > 80% internal carotid artery stenosis. Therefore, the aim of the present randomized controlled trial was to analyze neurological and cardiovascular outcome of patients treated with elective CAS plus best medical treatment compared to best medical treatment only.

Multicenter, prospective, feasibility study designed to demonstrate the performance and safety of the Lumen Biomedical, Inc. FiberNet™ Embolic Protection System as an adjunctive device during carotid artery percutaneous intervention using the Guidant Acculink carotid stent in high surgical risk patients.

Patients with rheumatoid Arthritis (RA) and Ankylosing Spondylitis (AS) are at greater risk of developing cardiovascular disease. The reason(s) for this have not been well investigated, but there is a general understanding that systemic inflammation plays a part in the increased cardiovascular morbidity and mortality. In spite of the increased risk in these patients, they have not been included as a high risk patient group in cardiovascular prevention guidelines. The investigators have carried out a cardiovascular study of RA and AS patients, as well as patients with arthritis for the first time. The investigators have demonstrated cholesterol plaques in the carotid artery in some of these patients. Plaques in the carotid artery represent a risk for development of cerebral stroke and are significantly associated with myocardial infarction. These plaques, which are asymptomatic and do not cause haemodynamically significant narrowing, diameter reduction (i.e. operation is not indicated), are vascular atheromatous disease. Therefore, according to prevailing cardiovascular guidelines (SCORE 2007), these patients shall have secondary prevention with a lipid lowering agent with the LDL-cholesterol goal of 1.8 mmol/L and HDL-cholesterol > 1.0 mmol/L for men and > 1.1 mmol/L for women. Statins are cholesterol-lowering drugs, and have been shown to reduce the risk of cardiovascular disease significantly. In addition, reduction in the size of coronary plaques has been induced by statins, when the LDL has been reduced to 1.6-1.8 mmol/l. Plaques in the carotid or coronary arteries have not previously been treated and characterized in patients with RA, AS and other inflammatory forms of arthritis. The aim of this study is to treat patients with cholesterol plaques in the carotid artery with cholesterol-lowering medication, in the form of Rosuvastatin for 18 months, and characterize the effects on the plaques in the carotid and coronary arteries. In addition, the investigators want to clarify the connection between plaques in the carotid and coronary arteries in patients with RA, AS and other inflammatory forms of arthritis.

The impact on cardiovascular events achieved by statin therapy seems to be mostly attributable to the cholesterol-lowering effect with a highly debated contribution of the lipid-independent pleiotropic effects. However, a short-term benefit has been documented for patients treated with statins in acute coronary syndromes and other clinical settings. These observations strengthened the hypothesis of additional, so-called pleiotropic actions of statins. The investigators therefore sought to investigate how different lipid-lowering strategies (non-statin therapy, low-dose statin and high-dose statin) affects cellular composition of carotid plaque over a short-term period of three months. Specifically the investigators tried and dissect the LDL-C lowering impact on plaque cellular composition as compared to the lipid-independent contribution on plaque macrophage and smooth muscle cells.

The purpose is to test whether a short-term, high-dose atorvastatin treatment (80mg once a daily (QD) from 3 days before to 3 days after CAS, then 20 mg QD until 30 days after CAS) is superior to conventional-dose atorvastatin treatment (20 mg QD from 3 days before to 30 days after CAS), in terms of efficacy for prevention of periprocedural ischemic brain damage in Chinese patients undergoing CAS.

Carotid endarterectomy (CEA) is the recommended treatment for symptomatic high degree stenosis of the internal carotid artery (ICA). ICA obstruction is often associated with an impaired cerebral autoregulation, implicating that cerebral perfusion pressure becomes dependent on systemic blood pressure. Therefore, to maintain cerebral perfusion pressure in this type of patients intraoperative hypotension needs to be avoided. Different short-acting agents such as phenylephrine, (a drug with vasoconstrictive properties), or ephedrine (a drug with vasoconstrictive properties combined with an increase in heart rate) can be used to correct intra-operative hypotension. In healthy subjects these agents affect the cerebral perfusion differently despite an identical effect on the systemic blood pressure. Cerebral perfusion decreases after phenylephrine administration while it is preserved after the use of ephedrine. The optimal agent for correcting hypotension in CEA patients, and thus in a situation of an impaired cerebral autoregulation, is unknown. Therefore, the investigators propose to perform a prospective study observing the effect of phenylephrine and ephedrine on cerebral perfusion to make a recommendation regarding the use of either phenylephrine or ephedrine during CEA.

The primary aim of this protocol is to investigate a possible new, neuroprotective treatment to prevent cognitive deficits that occur after carotid endarterectomy. We will investigate whether a widely used antibiotic agent - minocycline - that has shown neuroprotective effects in animal models of neurological diseases - can reduce the cognitive deficits associated with the surgical procedure of carotid endarterectomy (CEA). Because these cognitive deficits are believed to be a result of small strokes (due to emboli and/or hypoperfusion), this study will provide preliminary data on the use of this drug as a neuroprotective agent in stroke - a leading cause of disability. (1) The first aim of this study is to examine whether 5 doses of minocycline administered 36 hrs before and 1 dose 12 hrs after the surgical procedure in patients undergoing CEA are effective to reduce the cognitive deficits associated with this procedure as compared with placebo. a. The null hypothesis is that there is no difference in cognitive performance changes after CEA between the patients that receive placebo or minocycline.