14 Clinical Trials for Various Conditions
Moderate (50-69%) asymptomatic carotid artery stenosis (ACAS) is an important and under-appreciated contributor to balance and mobility dysfunction. This is significant because declines in balance and mobility are a significant predictor of falls, disability, loss of independence, and death in older adults. Further, falls and fall-related injuries in older adults cost approximately 50 billion dollars annually in the United States, and are the leading cause of adverse events reported by the Veterans Health Administration. This proposal seeks to: 1) investigate the impact of a supervised aerobic and challenging balance exercise program on balance and mobility function in patients with moderate ACAS; and 2) elucidate whether these changes are related to changes in cerebral perfusion. With 830,000 Veterans estimated to have moderate ACAS and at risk for balance and mobility dysfunction and increased falls, the findings from this study could have significant impacts on the clinical management, quality of life, and functional independence of Veterans with moderate ACAS.
We aim to determine whether cognitive impairment attributable to cerebral hemodynamic impairment in patients with high-grade asymptomatic carotid artery stenosis is reversible with restoration of flow. To accomplish this aim CREST-H will add on to the NINDS-sponsored CREST-2 trial (parallel, outcome-blinded Phase 3 clinical trials for patients with asymptomatic high-grade carotid artery stenosis which will compare carotid endarterectomy plus intensive medical management (IMM) versus IMM alone (n=1,240), and carotid artery stenting plus IMM versus IMM alone (n=1,240) to prevent stroke and death). CREST-H addresses the intriguing question of whether cognitive impairment can be reversed when it arises from abnormal cerebral hemodynamic perfusion in a hemodynamically impaired subset of the CREST-2 -randomized patients. We will enroll 385 patients from CREST-2, all of whom receive cognitive assessments at baseline and yearly thereafter. We anticipate identifying 100 patients with hemodynamic impairment as measured by an inter-hemispheral MRI perfusion "time to peak" (TTP) delay on the side of stenosis. Among those who are found to be hemodynamically impaired and have baseline cognitive impairment, the cognitive batteries at baseline and at 1 year will determine if those with flow failure who are randomized to a revascularization arm in CREST-2 will have better cognitive outcomes than those in the medical-only arm compared with this treatment difference for those who have no flow failure. We hypothesize that hemodynamically significant "asymptomatic" carotid disease may represent one of the few examples of treatable causes of cognitive impairment. If cognitive decline can be reversed in these patients, then we will have established a new indication for carotid revascularization independent of the risk of recurrent stroke.
Carotid revascularization for primary prevention of stroke (CREST-2) is two independent multicenter, randomized controlled trials of carotid revascularization and intensive medical management versus medical management alone in patients with asymptomatic high-grade carotid stenosis. One trial will randomize patients in a 1:1 ratio to endarterectomy versus no endarterectomy and another will randomize patients in a 1:1 ratio to carotid stenting with embolic protection versus no stenting. Medical management will be uniform for all randomized treatment groups and will be centrally directed.
Background: In a previous study, information verbally presented as relative risk (e.g. "50% less likely") or qualitative risk (e.g. "significantly less likely") resulted in many more people (66%) choosing a surgical procedure for narrowing or artery in the neck than people presented with absolute risk (e.g. "11% versus 5% over 5 years"), annualized risk (e.g. "2% versus 1% per year for 5 years") and event-free survival (e.g. "95% versus 89% over 5 years") (33%). Objectives: The purpose of this study is to determine whether the same observations are true for information that is presented visually as a bar graph. In addition, the investigators also seek to determine whether subjects feel that they understand the information better when presented visually as compared with verbally. Methods: 450 subjects will be approached in the neurology clinic as they are waiting for their office visit. If the subject agrees to participate in this 10 minute study, they will be taken to a quiet room where they will watch a 1 minute video on a laptop. The video will feature an acting physician. The presenter will be the same for all experiment groups. The presenter will describe a hypothetical medical situation in which a narrowing of one of the carotid (neck) arteries is present. The presenter will then describe the risk of a stroke related to that condition if the subject chooses medical therapy versus medical and surgical therapy. The presentation of risk will vary and may be presented in one of 3 different ways including a qualitative description, an absolute risk reduction over a fixed time period, and a relative risk reduction. These three risk groups will be presented either verbally or visually through bar graphs. In the visual subject groups, the presenter will be holding up a graph and remain silent while the graph is shown. The amount of time allotted for the graph on the video will be equal to the amount of time it takes the presenter to say the information in the auditory subject groups. Given that there will be 2 sensory modalities (verbal of visual) and 3 different presentation formats, there will be a total of 6 different videos. After the video is complete, the subject will be asked to complete a 1 page survey which will ask about the patient's age, gender, educational level, reason for the medical visit, and final decision about choice of treatment. The subjects will also answer how well they understood the data by making a mark on a 10 cm horizontal line.
Carotid artery plaques are known to cause stroke. Cognitive impairment is an insidious but poorly understood problem in patients with carotid plaques. Cognitive function describes how people perform mental processes such as thinking, learning and problem solving. Asymptomatic carotid plaques may affect 1 million Veterans who may be at risk for cognitive impairment. In this study, the investigators will uncover the extent of cognitive impairment in Veterans with carotid stenosis who are currently labeled "asymptomatic". Programs to prevent or mitigate cognitive impairment will depend on identifying the mechanisms by which this occurs. The investigators will use sophisticated 3D imaging techniques developed by the group to measure the structure and composition of plaques, number of particles breaking off from them, blood levels of chemicals that could disrupt them, and blood flow restriction to the brain from them. This will help identify patients at risk for cognitive impairment who may benefit from preventative measures and improve selection of patients to decrease unnecessary surgical procedures.
The purpose of this study is to determine patient variables, physician presenter variables, and information variables that might affect clinical decision making in asymptomatic carotid stenosis. The hypothesis is that information variables are the most significant determinant of clinical decision making.
Carotid Disease causes 10% of strokes. The Investigators are attempting to investigate the use of Transcranial Doppler to see if this is and effective, efficient, and/or valid way to identify individuals at highest risk for thromboembolic events from carotid disease. The plan is to plot the number of high intensity transient transcranial doppler signals with the category of patient (asymptomatic, symptomatic, and actively symptomatic) and evaluate if a relationship exists. The Investigators hypothesize that a linear relationship exists in that the higher the number of HITS the more symptomatic the patient. If results demonstrate the numbers of HITS correlate with the severity of disease this could potentially identify asymptomatic patients having subclinical symptoms who would benefit from a more urgent surgical intervention versus the current standard of care of elective intervention.
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).
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 subjects 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.
The trial randomise patients with asymptomatic carotid artery narrowing in whom prompt physical intervention is thought to be needed, but there there is still substantial uncertainty shared by patient and doctor about whether surgery or stenting is the more appropriate choice. The study is looking at immediate risks (within one month)and at long term benefits
The study is being conducted to demonstrate the non-inferiority of carotid artery stenting (CAS) using the Emboshield® Embolic Protection System with the Xact® Carotid Stent System to carotid endarterectomy (CEA) for the treatment of asymptomatic extracranial carotid atherosclerotic disease.
The purpose of the study is to test a new amplified stethoscope(AudioDoc) that can detect the presence of bruit by using an acoustic signal to represent the bruit. This pilot study will address two questions: is there a detectable difference in recorded sound signal of carotid and femoral bruit when compared to sound signals captured when there is no bruit present; is the use of a visual recorded signal more accurate in identifying carotid and femoral bruit when compared to traditional auscultation with a regular stethoscope and ultrasound.
The purpose of the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST) is to compare the relatively new procedure of stent-assisted carotid angioplasty (CAS) to the traditional and accepted surgical approach of carotid endarterectomy (CEA) for the treatment of carotid artery stenosis to prevent recurrent strokes in those patients who have had a TIA (transient ischemic attack) or a mild stroke within the past 6 months (symptomatic) and in those patients who have not had any symptoms within the past 6 months (asymptomatic).
The investigators hypothesize that pre-operative statin use is neuroprotective at maximal doses. The goals are to determine the safety, feasibility, and efficacy of maximizing statin doses for two weeks (12-18 days) prior to CEA using change in performance on a battery neuropsychometric tests as outcome measure. Study will recruit patients based on their preexisting statin regimen. The investigators hypothesize that in asymptomatic CEA patients: 1) Pre-operative statin use is neuroprotective against early cognitive dysfunction (eCD) and lowers the risk of early mortality. 2) Maximal doses may be essential in achieving optimal neuroprotection against eCD.