Active clinical trials for "Hypotension, Orthostatic"

A subset of patients suffering from chronic fatigue syndrome exhibit symptoms of neurally mediated hypotension. While the underlying pathophysiology of chronic fatigue syndrome is not precisely understood, a dysfunction of the autonomic nervous system is thought to play a role in this subset of patients. In several small studies, subjects within this subset have noted improvement in their chronic fatigue symptoms when treated for their neurally mediated hypotension. As droxidopa acts on the autonomic nervous system and has been shown to ameliorate symptoms of neurally mediated hypotension, it is hypothesized that droxidopa could aid in the treatment of chronic fatigue symptoms. Neurally mediated hypotension has been associated with patients suffering from chronic fatigue syndrome. Droxidopa meanwhile has been approved in Japan for the treatment of the symptoms of neurogenic orthostatic hypotension. As such, it is hypothesized that regulating the autonomic nervous system in patients with Chronic fatigue syndrome may prove to be clinically beneficial.

Orthostatic hypotension following total hip arthroplasty is known to limit the ability of patients to perform physical therapy (PT) and increase the length of hospital stay and costs. Our goal is to prospectively study the effects of oral midodrine on the signs and symptoms of orthostatic hypotension in 20 patients and the effects of intravenous fluid on the signs of symptoms of orthostatic hypotension in 10 patients. Midodrine will be administered to patients with suspected low SVV, and an intravenous fluid bolus will be administered to patients with low CO. 120 patients will be consented with a view to studying 30 patients who meet the inclusion criteria for orthostatic hypotension. Patients who receive midodrine or the fluid bolus will undergo hemodynamic measurements at 30 min, 1 hr, 2 hrs, 3 hrs, and 4 hrs post-intervention. All patients will undergo measurements for blood pressure, arterial augmentation index, and heart rate at baseline (pre-op; holding area) and the time of first PT attempt. Patients will be monitored up to post-operative day 3. The working hypothesis is that midodrine or fluid therapy will significantly raise the mean arterial blood pressure (MAP) by 5 mmHg+ and/or cause a significant change in the Orthostatic Hypotension Questionnaire (characterized by a two-point improvement in symptom score).

A Phase 3, multi-center, open-label study to evaluate the safety and tolerability of ampreloxetine in subjects with primary autonomic failures (MSA, PD, and PAF) and symptomatic nOH over 182 weeks.

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.

We are seeking male and female patients to voluntarily take part in a clinical research study. Patients must be aged 18 or older and diagnosed with symptomatic orthostatic hypotension (low blood pressure while in the upright position) due to Parkinson's disease, multiple system atrophy, pure autonomic failure or autonomic neuropathies (i.e. neurogenic orthostatic hypotension). Symptoms of low blood pressure include dizziness, lightheadedness, changes in vision and generalized weakness upon standing. The main effect of the drug being studied is to increase blood pressure in the upright position so symptoms will decrease. The purpose of this clinical study is to further assess the clinical effect of high dose midodrine hydrochloride (ProAmatine®), an approved treatment for orthostatic hypotension. During the course of the study, participants will receive either ProAmatine® or a placebo. Assessments will be made using questionnaires that measure symptom and activity levels. Blood pressure in the lying down, sitting and standing positions will be measured. Patients will also complete standing time assessments. They will be asked to remain standing without moving until they feel sufficiently lightheaded, or dizzy, or feel faint so that they would feel more comfortable sitting down.

Orthostatic hypotension is a major complication of hemodialysis and interferes with everyday activities in hemodialysis patients. Since information regarding the use of droxidopa in clinical trials relating to orthostatic hypotension of chronic hemodialysis patients is limited in Taiwan, this study is designed for evaluation the efficacy and safety profile of droxidopa on orthostatic hypotension treatment / prevention in hemodialysis patients.

The purpose of this study is to try different medications in patients with low blood pressure and other problems with their involuntary (autonomic) nervous system. The pharmacological trials in this study will perhaps lead to more effective treatment. The protocol includes single dose trials, dose-selection trials, 5-day trials and chronic (approximately 2 months) trials, although only dose-selection trials were consistently performed and have results presented.

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.

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 study will see if a special piece of equipment can help burn patients who have been in bed for a long time to get out of bed without feeling dizzy or faint.