View clinical trials related to Cardiovascular System.
Filter by:The goal of this clinical trial is to evaluate in clinically healthy young people if: - after caffeine ingestion, there are variations in blood velocity of the middle cerebral arteries (VMCA), - this variation is dependent on the administered dose. Transcranial Doppler ultrasonography was used to record blood VMCA in three groups of 15 clinically healthy young adults each - no caffeine, low caffeine (45 mg) and high caffeine group (120 mg). Transcranial Doppler ultrasonography provided simultaneous bilateral VMCA measurements while subjects performed functional tests (hyperventilation and hypoventilation orders) and three cognitive activities (Test 1, short-term remembering, Test 2, solving a vocabulary problem, and Test 3, solving a math problem) each in 31-second tests with 1-minute rest between them. Participants were assessed before and 30 minutes after caffeine ingestion.
Cardiovascular disease is one of the most important causes of death and disability in the world. An autonomic imbalance is associated to cardiovascular risks and disorders. Electrical stimulation (ES) applied by surface electrodes is a non-invasive therapeutic approach with low side-effects. In the last years, some studies had investigated the effects of ES on the autonomic nervous system and cardiovascular system. However, different intensities, frequencies and electrode locations had been used, which makes difficult to clarify the optimal parameters. The aim of this study is to analyze the effects of ES on autonomic nervous modulation in healthy subjects comparing three different locations of application for ES. Participants will be aleatory assigned to one of three groups for a single-session of 20-minute transcutaneous ES: a) an auricular intermittent ES in an area that is believed to be connected to the vagal nerve (cymba conchae); b) an auricular sham intermittent ES, meaning a real ES but applied on an ear location not connected to the vagal nerve (scapha); and c) an upper back continuous ES (C7-T4), a placement that is thought to be connected to the stellate (sympathetic) ganglion. All the protocols will be stated at a non-painful intensity. After that, the hand grip exercise will be executed. The heart rate variability (HRV) and heart frequency (HR) will be measured in four main times: the baseline, in the final minutes of the ES, after the ES and after finishing the hand grip exercise. Blood pressure will be measured also at all the time points except during the ES due to the possibility of interferences. Adverse effects will be assessed after ES and 48 h later. The study will provide initial knowledge about how different electrical stimulation locations contribute to reduce sympathetic excitation and improve the sympathovagal balance.
A study to explore whether different temperatures of warm water footbaths have different effects on the cardiovascular system, the autonomic nervous system and the general well-being of healthy women.
ENTAiER study is a multicentre randomized controlled trial to assess the efficacy and safety of eurythmy therapy and Tai Chi in comparison to standard care in chronically ill elderly patients with increased risk of falling. Subjects will be randomized to eurythmy therapy or Tai Chi or standard care alone. To investigate the changes in cardiovascular and sleep quality parameters under Eurythmy Therapy and Tai Chi in comparison to Standard Care in this trial, a substudy will be conducted only at the ARCIM Institute. The substudy will recruit enrolled participants from the ENTAiER trial to record various cardiovascular and sleep quality parameters. The aim is to compare changes in cardiovascular and sleep quality parameters under eurythmy therapy, Tai Chi and standard care alone in chronically ill elderly patients with increased risk of falling.
It is unclear if the rate of administration of the fluid challenge could affect the rate of fluid responsiveness. The role of this small-dose (the so called mini-FC) has been recently tested to assess if the infusion of a small amount of fluids (100 ml in 1 minute) could predict the final effect of the residual aliquot (i.e., 250 ml of FC test subdivided as follows: 100 ml in 1 minute and 150 ml in 9 minutes). Both the sudden increase in the stroke volume and the reduction of PPV and SVV after a bolus of 100 ml of crystalloids administered in 1 minute showed high sensitivity and specificity in predicting the final outcome of the FC. The primary aim of the present study is assess whether the does the rate of infusion of fluid challenge affect fluid responsiveness in neurosurgical supine patients. The secondary aim is to assess the reliability of the changes in SV, PPV and SVV after a mini-FC test in predicting the final fluid responsiveness.
This study aims to evaluate whether dietary supplementation with fish oil can protect against the cardiopulmonary effects induced by ozone exposure.
Cardiovascular disease is the leading cause of mortality worldwide. Endothelial dysfunction (ED) is the main mechanism which leads to atherosclerosis, where the balance between pro and antioxidant factors results in a decreased nitric oxide (NO) bioavailability. Xanthine OxidoReductase (XOR) is one of the main generators of reactive oxygen species (ROS). Uric acid (UA), a major antioxidant in human plasma and end product of purine metabolism, is associated with cardiovascular diseases since many years; however the precise mechanisms which relate UA to ED are still not well understood. The purpose of this study is to unravel the XOR and UA pathways involved in ED. Three groups of participants (young (< 40 y) male healthy participants [1] ; male and female helthy participants (40 to 65 y) [2] and patients with primary hypertension [3]) will be exposed to febuxostat (a strong and selective XOR inhibitor), or recombinant uricase (which oxidizes UA into allantoin) to vary UA levels and concomitantly control for confounding changes in XOR activity. Oxidative stress will be estimated by several markers. Endothelial function will be assessed by a laser Doppler imager in the presence of hyperthermia and endothelium stimulators. This study is specifically designed to untie the respective effects of UA and XOR pathways on oxidative stress and endothelial function in humans. The investigators will test the following hypothesis: 1. An extremely low level of uric acid after uricase administration induces endothelial dysfunction and oxydative stress, 2. A specific XO inhibitor limits unfavourable effects of the serum UA reduction elicited by uricase administration, 3. Endothelial function and oxydative stress are further improved with febuxostat as compared to placebo, 4. All these observations are more marked in hypertensives then in older participants than in young healthy subjects.
This study is designed to investigate the cardiovascular response (blood pressure, heart rate, electrocardiographic response and blood vessel reactivity response) to taking Adderall in healthy adults.
This is a pilot study to investigate whether patients at advanced age are fluid responders via a reversible fluid challenge, the passive leg raise test. This will be measured with a non-invasive cardiac output monitor, the LiDCO (LiDCO Hemodynamic monitoring) .
This study is being done to look at the cardiovascular response, if any, to intake of commercially available energy drink. We hypothesize that energy drink consumption compared to a control drink in healthy adults alters the cardiovascular hemodynamic system.The focus of this study is to elucidate the physiological/cardiovascular response to an energy drink consumption as compared to a control drink both at rest and during stressful conditions in healthy adults.