View clinical trials related to Syncope, Vasovagal.
Filter by:The purpose of this study to evaluate the effectiveness of metoprolol versus conventional treatment in the prevention of syncope recurrence in children and adolescents.
Syncope is a syndrome consisting of a relatively short period of temporary and self-limited loss of consciousness caused by transient diminution of blood flow to the brain (most often the result of systemic hypotension). The objective of this study was to evaluate the effect of salt supplementation in vasovagal syncope prophylaxis.
This randomized controlled trial will examine the impact of local anesthetic on the frequency of vasovagal reactions and the patients perception of pain during femoral arterial sheath removal after percutaneous coronary intervention.
Many individuals experience negative reactions when donating blood, including dizziness, lightheadedness, or fainting. Such reactions may discourage them from donating again. This study will evaluate the effectiveness of pre-donation water consumption and a muscle tensing exercise during donation to reduce negative reactions among new blood donors. This study will also evaluate whether reducing negative reactions increases the likelihood of donors returning to give blood in the future.
The main purpose is to prevent syncope in patients with recurrent syncopal episodes caused by malignant vasovagal faints and bradycardia. Patients are treated by a special pacemaker (closed loop stimulation [CLS]) which can potentially identify an incipient attack and prevent syncope by pacing.
The main question in the study is whether people taking fludrocortisone are less likely to faint than people taking an inactive pill called a placebo. Fludrocortisone is a drug that stimulates the body to retain salt and water. The investigators know from some studies that it might prevent people from fainting at home and in the community, while they are carrying on with their lives. There is some evidence that salt and water retention help prevent fainting, but no one has a clear idea about whether this is true. This study will try to determine if that is true.
This study will investigate the relationship between susceptibility to hypnosis and regulation of the autonomic nervous system (nerves that control involuntary body functions, such as heart rate and sweating). Hypnosis is a state of mind in which the individual is highly focused, relatively unaware of his or her surroundings, and possibly more able to accept and use therapeutic suggestions. People vary in their responsiveness, or susceptibility, while in hypnosis. People with certain conditions, such as chronic fatigue syndrome (CFS), chronic pain, posttraumatic stress disorder (PTSD), and generalized anxiety disorder (GAD) have altered hypnotic susceptibility. Patients with chronic orthostatic intolerance (COI) often have symptoms similar to those of individuals with CFS, chronic pain, PTSD, and GAD, and this study will examine how patients with COI respond to hypnosis as compared with healthy normal volunteers. COI is a group of disorders characterized by intolerance to prolonged standing. Among them are neurocardiogenic syncope (NCS), in which patients have recurrent episodes of sudden loss of consciousness, and postural tachycardia syndrome (POTS), in which patients have a sustained increase in heart rate after standing. In addition to the comparison of COI and normal volunteer responses to hypnosis, the study will examine how hypnotic susceptibility is related to the ability to control autonomic functions such as blood pressure, heart rate, and sweating. The autonomic nervous system is activated when the body is stressed, not only from physical stimuli such as cold temperature, but also from mental stimuli, such as seeing a rattlesnake up close. Hypnosis may, therefore, be a useful tool to understand how the mind controls the autonomic nervous system. Healthy normal volunteers and patients with NCS or POTS who are 18 years of age or older may be eligible for this two-part study. In part 1, participants complete a questionnaire and are then tested for hypnotic susceptibility. For this test, a professionally trained physician guides the subject through a procedure to achieve a hypnotic state. The subject is asked to perform several simple tasks and is then guided back to a normal state of being. In part 2, the subject undergoes hypnosis again, during which the physician offers various suggestions while monitoring activity of the subject's autonomic nervous system. The subject is connected to various sensors that continuously monitor blood pressure, heart rate, blood flow, sweat response, skin electrical conduction, and brain wave activity. An intravenous catheter is inserted into an arm vein to collect blood samples. At the end, the subject is guided back to a normal state of being. The hypnosis session in part 1 is videotaped in order to: 1) permit review by a scientist who is unaware of the subject's condition and whose judgment will not, therefore, be biased; and 2) have a record of the experimental data. Only qualified investigators will view the videotape.