Active clinical trials for "Hypotension, Orthostatic"

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.

This study is aimed primarily at providing a simple and effective form of treatment to reduce the symptoms of Initial Orthostatic Hypotension (IOH) and prevent syncope. We will first characterize the physiology of IOH, and then we will study four sit-to-stand maneuvers, each with a different stress tests to identify the role of sympathetic activity vs. simple muscle contraction in IOH. Then we will complete an additional two sit-to-stands with interventions designed to decrease the blood pressure drop (and hopefully symptoms) with initial stand. These consist of physical counter maneuvers, which may be a possible treatment that can be used to mitigate the drop in blood pressure (BP) seen in IOH during a stand and relieve presyncope symptoms.

Abnormalities in the regulation of cardiovascular system due to autonomic nervous system (ANS) dysfunction may lead to a sudden decline in blood pressure (BP) upon standing, sitting or performing activities/exercises in patients with Parkinson's Disease (PD). This sudden decline in BP is known as 'orthostatic hypotension' (OH). OH may cause dizziness and/or black-outs, which may increase the risk of falls. As falls are potentially dangerous and disabling, it is important to prevent their occurrence. Keeping BP within normal range upon change of posture or with activities is therefore of great significance. Pooling of blood in the abdominal blood vessels may be one of the reasons for OH to happen. This research focuses on strengthening the weak abdominal muscles of the participants so that the compressive action of these muscles can help decrease such pooling. Therefore, the researchers hypothesize that strengthening the abdominal muscles shall prove to be helpful in controlling orthostatic hypotension by preventing a sudden decline in blood pressure of the participants upon assumption of upright posture. The secondary hypothesis is that there exists a significant difference in the response of the cardiovascular system to a variety of postures/activities/exercises when patients of PD having cardiovascular autonomic dysfunction are compared with patients of PD with normal ANS function. This study has two parts - stage 1 and stage 2. Only stage 2 is a randomized controlled trial. Stage 1 involves testing the functional integrity of the autonomic nervous system, and observation of the cardiovascular responses of the participants to different postures/activities/exercises and to the use of an abdominal binder (which is a compressive garment worn around the abdomen). Findings of stage 1 shall help the researchers better understand the cardiovascular abnormalities present in such patients at rest and with activity. Stage 2 involves strength training for the abdominal muscles that is to be done by the participant at her/his residence for a period of 3 months followed by a second round of autonomic function testing and observation of the cardiovascular responses to the use of abdominal binder. Findings of stage 2 shall help the researchers determine if strength training of the abdominal muscles can be a useful strategy to counter the cardiovascular abnormalities found in the participants during the testing in stage 1.

The main purpose of this study is to gather data and assess changes in patient-reported outcomes with the stellate ganglion blocks as treatment for their sympathetically-mediated long COVID symptoms.

We will test the null hypothesis that there is no diurnal (morning to afternoon)variability in the blood pressure response to the ingestion of water 16 oz.

This study looks to characterize gradients of dysfunction in the autonomic nervous system after spinal cord injury. The autonomic nervous system plays key roles in regulation of blood pressure, skin blood flow, and bladder health- all issues that individuals with spinal cord injury typically suffer. Focusing on blood pressure regulation, the most precise metric with broad clinical applicability, the investigators will perform a combination of laboratory, ambulatory, and imaging-based tests to probe the body's ability to generate autonomic responses. For both individuals with spinal cord injury and uninjured controls, laboratory-based experiments will utilize multiple parallel recordings to identify how the autonomic nervous system is able to inhibit and activate signals. The investigators anticipate that those with autonomic dysfunction after spinal cord injury will exhibit abnormalities in these precise metrics. The investigators will further have research participants wear a smart watch that tracks skin electrical conductance, heart rate, and skin temperature, which can all provide clues as to the degree of autonomic dysfunction someone may suffer at home. The investigators will look to see if any substantial connections exist between different degrees of preserved autonomic function and secondary autonomic complications from spinal cord injury. Finally, functional magnetic resonance imaging scans will be attained to characterize patterns of connectivity within the injured spinal cord. In a similar manner, the investigators will look to see if different patterns of spinal cord connectivity are more closely related to groupings of secondary autonomic complications. In accomplishing this, the investigators hope to give scientists important insights to how the autonomic nervous system works after spinal cord injury and give physicians better tools to manage these secondary autonomic complications.

Rationale: Systolic hypertension represents the leading risk for burden of disease among older adults (age >70 years), with an increasing prevalence due to the increase in lifespan. Antihypertensive drug treatment (AHT) is beneficial in fit (non-frail) older adults, with substantial (≈40 %) risk reductions for cardiovascular events and mortality. Scarce evidence exists on the risks of adverse effects related to AHT. It has been suggested in medical literature that AHT in frail elderly might cause cerebral hypoperfusion and/or orthostatic hypotension. Therefore, current guidelines advise clinicians to be more cautious regarding treatment targets in this population. However, the evidence for these adverse effects is limited to observational and cross-sectional data and opinion pieces. In contrast to the suggestion of potential adverse effects of AHT in elderly, recent experimental data and secondary analyses of clinical trials do not provide support for this statement. However, evidence in frail older patients remains scarce. Studies that directly examine the safety of AHT with regard to cerebral hemodynamics and orthostatic tolerance in frail elderly are needed to inform potential changes in current treatment guidelines and prevent undertreatment of hypertension in frail older patients. Objective: To examine the impact of medication induced systolic BP (SBP) reductions ≥10 mmHg, while reaching a treatment target of ≤140 mmHg, on cerebral blood flow (CBF) in frail elderly with untreated or uncontrolled systolic hypertension at baseline. We hypothesise that these blood pressure lowering targets (which are consistent with clinical guidelines for non-frail older patients) are not accompanied by detrimental reductions in CBF (i.e. >10% from baseline). Study design: An explorative observational study will be performed to examine the effects of medication induced SBP reductions ≥10 mmHg to office SBP ≤140 mmHg on CBF in frail elderly with untreated or uncontrolled hypertension. Participants will be treated as in usual patient care for older adults with hypertension. Participants will undergo one baseline assessment before exposure to (additional) AHT, followed by in duplo follow-up assessments 6-10 weeks after the start of AHT. The in duplo follow-up evaluations will be performed on separate days within 2 weeks while continuing treatment. Study population: Twelve frail (Clinical Frailty Scale 4-7) elderly (age ≥70 years) with untreated or uncontrolled systolic hypertension (office SBP ≥150 mmHg) that will be subjected to (additional) AHT as part of regular care. Main study parameters/endpoints: The change in resting CBF from baseline to follow-up (i.e. the average of the in duplo follow-up assessments). Secondary outcomes relate to cerebrovascular autoregulation (CA) and orthostatic tolerance. Nature and extent of the burden and risks associated with participation, benefit and group relatedness: Subjects will be subjected to AHT, essentially identical to what is considered 'guideline care', while their wellbeing will be monitored closely. Since all study procedures and used measurement techniques are non-invasive, the nature and extent of burden and risks associated with participation and measurements are negligible.

Background: In recent years, the changes of cognitive function in mild cognitive impairment have attracted attention. Methods/design: We will follow up at 3. The primary outcome will be the measurement of cognitive function using neuropsychological assessment scales such as MOCA, MMSE, etc... Minor variables will be included plasma biomarkers (Aβ, Tau, GFAP, etc.), multimodal brain electrophysiology (P300, VP300, heart rate variability, etc.), and neuroimaging indicators (NODDI).

This is a prospective single-center randomized crossover control study that aims to evaluate the effects of non-invasive transcutaneous spinal cord stimulation in patients with known or suspected orthostatic hypotension.

The purpose of this study is to identify the effects of non-pharmacological and pharmacological anti-hypotensive treatment interventions on orthostatic hemodynamic responses, symptoms of autonomic dysreflexia and orthostatic hypotension, and levels of fatigue and comfort in hypotensive individuals with SCI.