Active clinical trials for "Autonomic Nervous System Diseases"

Refractory cardiogenic shock is characterized by a decreased in cardiac output with hypo-responsiveness to increasing doses of catecholamines resulting in a profound tissular ischemia. VAECMO, by restoring a circulatory flow, could be associated to a major reperfusion syndrome which may lead some patients to multiple organ failures and death. Pathophysiology of this syndrome includes 1/an hyper-adrenergic state secondary to the over activation of the sympathetic system and 2/ a major release of pro-inflammatory cytokines. As adrenoreceptors are also exhibited on immunes cells, the pro-inflammatory state might be enhanced by the over-activation of the sympathetic system.

The study has three aims: To investigate the influence of cardiovascular autonomic function on pain sensitivity at rest in patients with fibromyalgia and age- and sex-matched controls To investigate the influence of cardiovascular autonomic function at baseline and during exercise on the pain response following submaximal isometric exercise To study the relation between the pain response following physical and cognitive tasks (exercise and mental math, respectively).

Autism Spectrum Disorders (ASD) is a neurodevelopmental disorder which involves social and behavioural impairments. Autonomic dysfunctions and disturbed sleep were often associated to ASD. The investigators proposed to explore the impact of physical activity on these disorders. In this context, it is necessary to characterize the cardiorespiratory capacities of ASD children in order to promote physical activity for this population. To examine potential differences between ASD and control children, some explorations were proposed: a maximal treadmill test, motor evaluation, and orthostatic test (for the evaluation of autonomic nervous system). An actimetry during one week (evaluation of physical activity and sleep) completed this study in order to specify sleep characteristic and established the possible link between physical activity sleep characteristics and physical fitness in ASD children.

People with POTS, autoimmune autonomic neuropathy (AAN), pure autonomic failure (PAF), SFN and Ehlers Danlos Syndrome (EDS) do not only suffer from orthostatic symptoms such as dizziness, headache, neck pain, blurred vision or (pre-) syncope. They also experience deficits in attention and concentration (more precisely deficits in selective perspective, operating speed, executive functions and memory performance) mainly in upright position. Only few studies concerning cognitive impairment in autonomic neuropathies, their frequency, aetiology and therapy exist. Many patients concerned, especially with POTS, report attention deficits and "brain fog" with problems in their everyday life and work, predominantly in upright posture. Specific symptomatic or medical therapies do not exist. Medical treatment with Modafinil is discussed and part of a current study at Vanderbilt Autonomic Dysfunction Centre (1-5). The investigators want to investigate if problems of concentration, attention and/or cognitive dysfunction exist in people with POTS, AAN, SFN and EDS compared to healthy controls (HC). Thus the investigators use detailed clinical, autonomic and neuropsychological tests in different body positions (lying, sitting and standing) as also acute therapy (leg crossing).

The main aim of this study is to gain an in-depth knowledge of cardiopulmonary and autonomic health consequences, and related risk factors among people with long-term high-level spinal cord injury. The result of this study will form the basis for further research to improve prevention strategies and risk prediction of cardiopulmonary disorders in people with spinal cord injury.

Multiple system atrophy (MSA) is a disorder of the nervous system of unclear cause. In MSA there is degeneration (progressive loss) of nerve cells in several brain and spinal cord regions. The result is a variety of symptoms, from physical (parkinsonism, ataxia, incoordination, falls, slowness) to autonomic (fainting, bladder incontinence, sexual dysfunction) to sleep problems (dream enactment, sleep apnea). This research aims to help us better understand the patterns and timing of nerve degeneration relatively early in the disease, and how this affects symptoms and progression. For instance: Does MSA affect certain nerves that stimulate heart pumping? If so, does the severity of loss of heart nerves affect disease progression and survival? It is thought that MSA does not affect memory and thinking much, unlike other diseases (such as Parkinson's). Is this accurate? Is there loss of nerves that transmit acetylcholine (a neurochemical important in mental functioning)? What can we learn about mood and sleep in MSA, through visualizing the serotonin system in the brain? How does this relate to symptoms that subjects report in these often underappreciated areas? To answer these and other questions, investigators will take images of specific nerves in the brain and heart using Positron Emission Tomography (PET) scans. Such imaging gives us information that cannot be obtained from MRIs and CT scans. We will measure the levels of several nerve cell types: serotonin, acetylcholine, and norepinephrine. Subjects will also have many standardized assessments including quality-of-life and symptom assessments, neurological examination, autonomic assessments, neuropsychological assessments, coordination tests, and even assessments of vision and sense of smell. By pooling these results from many MSA patients, and comparing with other diseases (such as Parkinson's disease) we hope to gain a better understanding of what is happening early in MSA. Such knowledge could be very valuable in future efforts to develop better therapies in this rare disease.

The purpose of this research study is to better understand what causes dysautonomia and how this affects blood pressure and pulse. Dysautonomia is a condition of the autonomic nervous system. It is associated with fluctuations in blood pressure and pulse and may cause symptoms of nausea and belly pain, fatigue, excessive thirst, lightheadedness, dizziness, feelings of anxiety or panic, and fainting. A common example of dysautonomia is postural orthostatic tachycardia syndrome or POTS. Sometimes symptoms worsen when people move from lying down to standing, called orthostatic intolerance. We would like to learn more about the link between orthostatic intolerance and nausea. While medications currently used to treat orthostatic intolerance and nausea have proven to be effective in some patients, this may not be the best treatment for everyone as long term use could pose certain risks including high blood pressure. In order to provide a more focused and safer treatment for patients suffering from nausea and orthostatic intolerance, we have looked at how the blood pressure, pulse, and certain blood tests change during a tilt table test. This test helps to create the same circumstances that patients with orthostatic intolerance experience when they stand. To better understand if some of these problems are associated with the brain, we will study MRI in patients with dysautonomia compared to children without dysautonomia. This information may allow us to use alternative and safer treatments in the future.

Autonomic nerve function is involved in both blood pressure (BP) regulation and the pathogenesis of coronary artery spasm (CAS), but few studies have been published about the relationship between CAS and BP, with the exception of studies that explore hypertension as a risk factor for CAS. The purpose of this study was to investigate the incidence of CAS and atrioventricular (AV) block in association with BP level. The investigators will register consecutive patients who underwent coronary angiography with an acetylcholine (Ach)-induced provocation test from November 2004 to May 2012. The investigators exclude from the patients who were taking antihypertensive drugs or who had a documented history of cardiovascular disease in order to avoid the confounding effects of cardiovascular medications on coronary vasomotion. CAS is defined as >70% luminal narrowing on Ach provocation and /or concurrent chest pain. The study population will be divided into quartiles of rising systolic BP and diastolic BP. The incidence of Ach-induced CAS according to each systolic BP/diastolic BP quartile will be evaluated.

It has been found that in some cases, when a person with Diabetes Mellitus has an episode of low blood sugar,or hypoglycemia, and then later exercises, he or she is vulnerable to another bout of hypoglycemia during that exercise. The purpose of this study is to determine what factors during the previous bout of hypoglycemia might cause another bout of hypoglycemia while exercising later.

This study involves sampling blood from both normal volunteers and patients with diseases known or suspected to involve body chemicals called catecholamines. The blood will be used to establish normal values for plasma levels of catecholamines and related neurochemicals; to test for abnormal neurochemical patterns in patients; and to establish a "bank" of DNA from normal volunteers and from patients to be used in future studies about possible alterations of catecholamine-related genes. Study participants will report to NIH after fasting overnight except for water or noncaloric, noncaffeinated beverages. They must not have taken Tylenol for at least 5 days. Blood will then be drawn. DNA will be extracted and stored in the freezer for future studies.