View clinical trials related to Cardiovascular System.
Filter by:This is a randomized controlled human exposure crossover study. Investigators aims to assess the acute effects of low temperature exposure and the underlying mechanisms.
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.
The long-term objective of this research line is to identify and implement an effective and feasible intervention capable of preventing and/or reducing the burden of cardiometabolic and obesity-related diseases that affect Mississippians and others. The pursuit of this long-term objective will begin with achieving the specific aims proposed in this pilot project, which are to determine the effect of single sprint training for improving (1) systemic macro-vascular function, (2) local and systemic micro-vascular function, and (3) cardiorespiratory fitness. These aims will be achieved using a randomized controlled trial whereby 40 males and females will be randomized into an intervention group (n=20) or time-matched negative control group (n=20). The intervention group will perform a single maximal effort sprint on a cycle ergometer for twenty seconds 3 days/week for 4 weeks and the control group will be asked to maintain pre-intervention habits/behavior over 4 weeks. All outcome measures are non-invasive, and will be assessed pre-, mid-, and post-intervention, with the exception of cardiorespiratory fitness, which will be measured pre- and post-. To achieve aim 1, brachial artery flow-mediated dilation via ultrasonography and systolic and diastolic blood pressure via automated oscillometry will be measured on the arm. To achieve aim 2, post-occlusive reactive hyperemia via near-infrared spectroscopy and reactive hyperemia via ultrasound will be measured in the arm and leg, respectively. To achieve aim 3, pulmonary gas exchange will be measured during a graded exercise test on a cycle ergometer. All outcomes will be compared across time between conditions and sex with a three-way Bayesian Repeated Measures ANOVA using pre-values as covariates and an uninformed prior. 95% credible intervals will also be calculated to power future investigations using this intervention. If the intervention is found effective, future studies will be conducted to determine the efficacy of the intervention in larger groups and more clinical populations, and to determine the mechanisms mediating the adaptations. If ineffective, the knowledge gained will be used to develop future interventions.
This is a randomized controlled human exposure crossover study. Investigators aims to assess the acute effects of high temperature exposure and the underlying mechanisms.
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.
This study aims to assess the effects of acute exposure to traffic-related air pollution and the underlying mechanisms.
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.