View clinical trials related to Hypotension, Orthostatic.
Filter by:Neurogenic Orthostatic Hypotension (NOH) is clinically defined as a consistent drop in systolic blood pressure (SBP) ≥30mmHg upon standing from a seated or lying position. However, 50% of NOH patients also have associated supine hypertension. It has been proposed that supine hypertension is the result of intact post-ganglionic sympathetic nerves and therefore due to residual sympathetic tone. Furthermore, research investigating the effects of melatonin shows blood pressure implication of this naturally secreted hormone. Specifically, melatonin has been investigated as a non-traditional anti-hypertensive agent for patients with essential and nocturnal hypertension. Central and peripheral mechanisms have been proposed to help explain how melatonin reduces blood pressures. Therefore, we aim to identify NOH patients as having either intact or denervated post-ganglionic sympathetic nerves, monitor the correlation to supine hypertension and subsequently investigate the effects of melatonin on blood pressure in these patients.
While treatment strategies for OH have been identified for use in persons with acute SCI, the field of SCI medicine lacks a gold standard for treatment thresholds and well-defined outcome parameters. Comprehensively documenting the impact of orthostatic hypotension (OH), regardless of symptoms, during acute rehabilitation and identifying the effects of two different treatment approaches on therapy participation and adherence to an intended rehabilitation plan could have a significant impact on clinical practice in the acute rehabilitation setting following SCI.
The purpose of this study is to learn more about the effects of midodrine and droxidopa, two medications used for the treatment of orthostatic hypotension (low blood pressure on standing), on the veins of the abdomen of patients with autonomic failure. The study will be conducted at Vanderbilt University Medical Center, and consists of 2 parts: a screening and 2 testing days. The total length of the study will be about 5 days. About 34 participants will be screened for the study.
Drug therapy for patients suffering from autonomic failure and neurogenic orthostatic hypotension are scarce and not effective. If left untreated, these patients have the highest risk of syncope, falls and fall-related injuries. The proposed study will determine the clinical benefit of a commercially available drug, atomoxetine, to reduce symptoms associated with neurogenic orthostatic hypotension in patients with autonomic failure.
Suspension syndrome refers to a potentially life-threatening condition that can occur in unconscious persons after prolonged suspension in a harness. To date, our understanding of the pathophysiology and appropriate treatment is based primarily on case reports and expert opinion. The main pathophysiological hypothesis implicates blood pooling in the lower extremity and lack of return via muscle pumping. However, a recent French study could not support this hypothesis. Other mechanisms, such as a central vagal reflex may play a role in the pathophysiology of suspension syndrome. The aim of this study is to better understand the pathophysiological basis of suspension syndrome and to develop practical recommendations for prevention and treatment.
The purpose of this study is to learn more about the regulation of the veins of the abdomen by the autonomic (involuntary) nervous system, and how this may affect high blood pressure. Normally, the autonomic nervous system controls how much blood flows in the veins. In people with high blood pressure, however, the autonomic nervous system is changed. This change may affect the way blood flows in the veins of the abdomen which may play a role in their high blood pressure. About 32 participants will be screened for the study. The investigators estimate 16 will be eligible to participate in all of the study days.
This multiple-center, 3-part, single-blind dose escalation (Part A), randomized, double-blind (Part B), and open-label multiple dose extension (Part C) study will be conducted in male and female subjects with neurogenic orthostatic hypotension to evaluate the effect of TD-9855 in improving symptoms of orthostatic intolerance.
The purpose of this study is to determine if the pulse pressure changes are different whether patients are training in a traditional tilt table as compared to a robotic assisted tilt table, which induces leg movement.
One of the most physiologically demanding things that older people do every day is to get up in the morning. After spending a night laying flat, where the blood distributes evenly across the body, when they stand in the morning (and the blood rushes to their feet), their cardiovascular system may not be able to compensate and maintain blood flow to the brain. This phenomenon is known as orthostatic or postural hypotension. The investigators have found in a group of young individuals that use of a dawn-simulation light that gradually wakes the brain is able to increase cardiovascular tone prior to arising. The goal of this experiment is to determine whether this dawn simulation light is able to increase cardiovascular tone in older adults such that they would have reduced or absent postural hypotension when they awaken in the morning. This would greatly reduce the risks of falls and their associated morbidities in older adults.
Pharmacologic approaches to increase levels or actions of the vasodilatory peptide angiotensin-(1-7) are currently in development for the treatment of hypertension based on findings from animal models. There are limited and contradictory clinical studies, however, and it is not clear if this peptide regulates blood pressure in humans. The purpose of this study is to better understand the cardiovascular effects angiotensin-(1-7) in human hypertension, and to examine interactions of this peptide with the autonomic nervous system. The investigators propose that the difficulties in showing angiotensin-(1-7) cardiovascular effects in previous clinical studies relates to the buffering capacity of the baroreceptor reflex to prevent changes in blood pressure. Autonomic failure provides the ideal patient population to test this hypothesis. These patients have loss of baroreflex buffering and have low levels of angiotensin-(1-7) in blood. The investigators will test if angiotensin-(1-7) infusion can lower blood pressure in patients with autonomic failure, and will determine the hemodynamic and hormonal mechanisms involved in this effect.