26 Clinical Trials for Various Conditions
The goal of this study is to better understand how the back part of the eye-called the retina and the choroid-changes during pregnancy. Specialized photos of the eye will be taken at three different timepoints: early in pregnancy (first or second trimester), late in pregnancy (third trimester), and after delivery. This imaging is non-invasive and does not require contact with the surface of the eye. The photos taken will allow assessment of specific parameters, like blood flow and the health of specialized cells that support vision. Understanding how the eyes change during pregnancy may help guide how retina specialists understanding of retinal disease during pregnancy and better inform pregnancy outcomes.
The goal of this study is to assess whether undergoing surgical repair of the rotator cuff with the additional intervention of whole blood fibrin clot will improve rotator cuff vascularization at the bone-tendon interface repair site and patient outcomes compared to those who do not receive the whole blood fibrin clot intervention.
This is a pilot study of DCE MR imaging to detect vascular changes in the vagina during and after radiotherapy n patients receiving adjuvant brachytherapyfor cervical or endometrial cancer.
The Multi-Ethnic Study of Atherosclerosis (MESA) - Chronic Obstructive Pulmonary Disease (COPD) Study aims to characterize the pulmonary vascular changes and their biology in early COPD using imaging, gene expression profiling and peripheral cellular measures.
This study will determine whether upper arm vessels increase in size following forearm loop arteriovenous graft placement and the timing of these changes.
Pediatric heart transplant patients have a high-risk cardiovascular profile affecting their long-term outcomes and survival. Currently, no effective cardiovascular preventative care is provided for this pediatric population, in part, due to the fact that clinic-based programs are not easily accessible to children and their families. However, tele-health has been show to improve medical outcomes by making care more accessible to these patients. This study aims to meet the urgent need for an effective and sustainable delivery of preventative care to pediatric heart transplant patients using a diet and exercise intervention program delivered live over the internet direct to these patients' homes.
The investigators propose that evidence of chronic cerebrospinal venous insufficiency (CCSVI) may be evident in the vasculature of the fundus. The investigators will be examining fundi of multiple sclerosis patients and Ehlers-Danlos patients to see if evidence of CCSVI can be found in these patients having high risk for CCSVI. The investigators will read the fundus photos, compared to age-matched normals in a "blind" fashion.
Improvement in cardiovascular mortality is related to changes in pathologic autoantibodies and in the number of circulating functional replicative competent endothelial progenitor cells (EPC's) after bariatric surgery.
The purpose of this study is to compare the vascular permeability of blood vessel walls (of the carotid artery) in pre-menopausal women who have metabolic syndrome (syndrome of having at least 3/5 following features- increased abdominal fat, low good cholesterol (HDL-C), elevated fasting blood fats (triglycerides), elevated blood pressure, an elevated fasting glucose) versus those women who are normal weight and with normal cholesterol, blood fats, blood pressure, and blood sugar. We are using a novel technology to measure vascular permeability known as dynamic contrast enhancement magnetic resonance imaging (DCE-MRI). The primary variable is ktrans ratio which is a mathematically derived quantity obtained from DCE-MRI. We are trying to identify novel markers of early atherosclerosis in young women.
Brain blood flow will be measured during a simulated postural change test and while breathing increased levels of carbon dioxide using magnetic resonance imaging.
Brain blood flow will be measured during a simulated postural change test and while breathing increased levels of carbon dioxide using magnetic resonance imaging.
Obstructive sleep apnea is a condition in which people have decreased breathing during their sleep. Untreated sleep apnea has been linked to increased risk for cardiovascular diseases. This research study is looking at blood clotting factors and blood vessel function in health volunteers and patients with newly diagnosed or untreated obstructive sleep apnea to better understand the underlying mechanisms for increased cardiovascular risk.
To evaluate the dose-response of relevant blood biomarkers to remote ischemic conditioning in patients with age-related cerebral white matter hyperintensities on MRI, in preparation for a subsequent larger efficacy trial.
Intracranial aneurysm rupture is a leading cause of hemorrhagic strokes which carry high mortality and disability rates as well as high healthcare costs. Unruptured intracranial aneurysms (UIA) are common in the general population, occurring in 1-2% of individuals. Previous studies have shown that UIA growth and rupture are strongly associated with each other, with growing aneurysms 9-12 times more likely to rupture, and nearly all aneurysms growing prior to rupture. Thanks to advanced medical imaging, UIA are now more and more often detected incidentally. However not all aneurysms qualify for preventive surgical or interventional procedures according to current International Study of Unruptured Intracranial Aneurysms (ISUIA) guidelines, and some must therefore be monitored for growth. Current guidelines are based heavily on size, an inconsistent predictor of future growth. To improve management strategies for individual patients and more comprehensively assess aneurysm risk, the investigators propose to identify risk factors related to growth. Aneurysm etiology is multifactorial, with both genetic and environmental contributions to aneurysm formation, growth, and rupture. Exploring new risk factors based on aneurysm natural history and understanding the mechanisms underlying aneurysm rupture have been extensive research areas. As previous studies have shown that quantitative imaging biomarkers (QIB) can provide a more accurate assessment of the characteristics of aneurysms, the investigators propose a combined study which identifies QIB associated with aneurysm growth to identify factors related to growth.
Despite advances in stroke care, women continue to face worse outcomes after stroke than men. This disparity in outcomes may be related to biologic sex-differences that manifest in the development and progression of atherosclerosis. Decades of cyclic changes in the hormonal milieu lead to different metabolic profiles in women. These changes may also explain sex-differences in risk factor profiles of atherogenesis and plaque composition. The investigators' objective is to conduct a cross-sectional MR imaging study of suspected stroke patients to compare the burden and composition of intracranial atherosclerosis and risk factors between men and women. Results from this study are expected to show that sex and sex-specific risk factors should be considered at the outset of stroke evaluation for risk-stratification. In the era of precision medicine, the investigators propose the role of sex should be a starting point in the clinical evaluation of stroke.
The objective of this study is to evaluate the performance of Modulated Imaging Inc.'s (MI) next generation Spatial Frequency Domain Imaging (SFDI) system to measure potential circulatory compromise.
In this research study the investigators want to learn more about the risk of developing blood vessel and heart disease from night-time sleep apnea. Sleep apnea is a condition that results from blocking of the throat during sleep. This study examines changes in blood pressure, blood vessel stiffness, heart size and levels of specific substances in the blood which may cause heart disease. This study is for children ages 5 to 13 years. The study involves 3 visits over 18 months. The first and last visits include an overnight sleep study (polysomnography or PSG). All the visits will include: * body measurements to measure growth and how weight is distributed, * resting blood pressure measurements, * heart measurements (electrocardiogram and ultrasounds of the heart and blood vessels), * 36 hour home ambulatory blood pressure measurements, * blood tests to look at things like fats, cholesterol, inflammatory factors, * questionnaires Optional parts of the study include DNA and for children 8 years and older, testing and questionnaires to learn more about how sleep relates to learning, memory and behavior issues.
The renin angiotensin system is a complex process involving hormones and enzymes that regulate blood volume and blood pressure. The hormone angiotensin II is responsible for making blood vessels narrow or constrict. Angiotensin II is found in the blood and can attach to special sites called receptors on blood vessel walls. These receptors are programmed to accept angiotensin II and cause a constriction of the blood vessel. This function is found in the genetic information of each individual person. Occasionally patients have changes in their genes related to angiotensin II receptors. These changes may result in the receptors acting differently to angiotensin II, which may affect the function of blood vessels. This study is designed to improve researchers understanding of the physiological effects on blood vessels associated with mutations of the genes responsible for angiotensin II receptor function.
Lower extremity revascularization combined with supervised exercise significantly improves walking performance compared to revascularization alone in people who have PAD without limb threatening ischemia. However, supervised exercise is inaccessible or burdensome for most PAD patients. We hypothesize that home-based exercise combined with lower extremity revascularization will significantly improve walking performance compared to revascularization alone in patients with PAD undergoing revascularization for disabling PAD. We further hypothesize that inorganic nitrate, a major source of nitric oxide (NO) abundant in beetroot juice, will improve walking performance after lower extremity revascularization, compared to placebo. In preclinical models, NO inhibits inflammation, neointimal hyperplasia, thrombosis, and vascular smooth muscle cell migration at sites of revascularization. NO increases angiogenesis and perfusion, repairs skeletal muscle damaged by ischemia, and stimulates mitochondrial activity. In a randomized clinical trial with a 2 x 2 factorial design, we will test the following two primary hypotheses in 386 patients randomized within three months of a successful lower extremity revascularization for disabling PAD: First, that home-based exercise combined with lower extremity revascularization will improve six-minute walk distance more than revascularization alone at 6-month follow-up (Primary Aim #1). Second, that nitrate-rich beetroot juice combined with lower extremity revascularization will improve six-minute walk, compared to placebo combined with revascularization at 6-month follow-up (Primary Aim #2).
Supervised exercise therapy (SET), consisting of treadmill exercise conducted three times weekly at a center while supervised by healthcare personnel, is first line therapy for people disabled by lower extremity peripheral artery disease (PAD). However, travelling three times/week to a center for SET is burdensome. Compared to SET, home-based exercise is more accessible and less burdensome. Yet, evidence-based guidelines recommend SET over home-based exercise for PAD. Walking exercise is first line therapy to improve walking distance for PAD, but it does not eliminate ischemic leg symptoms in most people with PAD. The investigators' work and that of others showed that nitrate-rich beetroot juice, which increases plasma nitrite, limb perfusion, and skeletal muscle function, significantly improved exercise tolerance and reduced non-response to exercise in people with and without PAD. The investigators will use a 2 x 2 factorial design to address two major barriers to achieving benefits from exercise therapy for PAD: First, guideline recommendations for supervised exercise therapy (SET) as first line therapy for PAD. Second, the inability of exercise therapy to eliminate PAD-related disability in most people with PAD. Participants will be randomized to one of four groups for 12 weeks: Supervised treadmill exercise + nitrate rich beetroot juice; supervised treadmill exercise + placebo, home-based walking exercise + nitrate rich beetroot juice, home-based walking exercise + placebo.
The research is designed as a randomized, 2-arm, parallel, controlled, human clinical trial to investigate the effects of avocado and mango consumption for 8 weeks on indices of macro- and micro- vascular function in individuals with prediabetes. FMD of the brachial artery, pulse wave velocity (PWV), central blood pressure (cBP), and Optical Coherence Tomography Angiography (OCTA) of the eye will be used for vascular assessments. The research plan will also explore cognitive and kidney function benefits of regular avocado and mango intake using specified cognitive tasks and kidney function biomarkers
The objective of this study is to assess the effect Spinal Cord Stimulators have toward improving vascular changes of diabetes mellitus in patients eligible for SCS placement based on their condition of painful diabetic neuropathy; we will evaluate improving their disability and quality of life, improving micro-circulatory changes induced by Diabetes Mellitus (DM), improving macro-circulatory changes induced by DM and improving arterial stiffness of the vessels of the lower extremity.
The goal of the study is to combine a collaborative and translational approach to evaluate the effect antiretroviral regimen switch to a dolutegravir containing regimen compared to continued treatment with a non- dolutegravir based regimen on on lipid and metabolic profiles, renal function, body composition, vascular function and diet.
Previous studies in animals and humans has shown that brief periods of reduced blood flow to one organ or tissue in the body can help protect other tissues from subsequent injury caused by reduced blood flow such as a stroke. This phenomenon is known as remote ischemic preconditioning and may help protect brain cells after a stroke. The investigators are studying a specific stroke type called subcortical stroke that is very common and has a high rate of recurrent stroke and cognition problems despite intensive prevention measures.
The purpose of this study is to determine whether reducing a patient's body temperature (mild hypothermia of 33 degrees Centigrade) will significantly reduce the risk of brain injury (notably reperfusion injury and hemorrhagic conversion) in patients who have suffered a significant interruption of blood flow to an area of brain (occlusion of large proximal cerebral artery) and have undergone successful removal of that interruption (revascularization).This will be achieved by comparing patients who have undergone hypothermia to those who have not.
The purpose of this trial is to determine whether the combination of thrombolysis and hypothermia is superior to thrombolysis alone for the treatment of acute ischemic stroke.