Active clinical trials for "Syncope"

This study will conduct tests with patients with primary chronic orthostatic intolerance (COI) to learn more about this disorder of the autonomic nervous system. Healthy normal volunteers and patients 18 years of age and older with COI may be eligible for this study. Participants undergo one or more of the following tests and procedures: Blood studies, including arterial catheter insertion to measure blood pressure and collect arterial blood samples, blood flow studies using sensors applied to the skin and a pressure cuff around a limb, blood volume studies using injection of radioactively labeled human serum albumin and gene studies to look for genetic abnormalities associated with certain proteins. Imaging studies, including CT scan of the adrenal glands, heart ultrasound, and PET scanning. Electrocardiogram Microdialysis to measures levels of chemicals in the body fluid of certain tissues. A thin tube is inserted into the skin and a solution is passed through it. Chemicals in the body tissues enter the solution in the tube. The solution is collected and the chemical levels are measured. Neck suction. Neck suction is applied to test a reflex the brain uses to regulate blood pressure. Perometry. Limb volume is measured using an infrared light that moves up the limb. Quantitative sudomotor axon reflex test to evaluate an aspect of autonomic nervous system function. A small amount of a brain chemical (acetylcholine) is applied to the skin with a tiny amount of electricity, and the sweat in a nearby patch of skin is measured. Skin electrical conduction test using sensors on the skin to measure sweat production. Skin and core temperature measurements using sensors on the skin and in the ear canal. Tilt table test. The subject lies on a table, secured with straps around the chest and legs. Sensors are placed on the arms and chest to monitor blood pressure, pulse rate, and heart rhythm. A catheter is placed in a vein in each arm to collect blood samples and give drugs. Another catheter is placed in an artery to draw blood and monitor blood pressure. The subject is given an infusion of norepinephrine and epinephrine, and baseline measures and blood samples are taken. The table is tilted upright and more measurements and blood samples are taken at intervals for up to 30 minutes. The table is returned to a horizontal position and additional measurements and samples may be taken. Drugs may be administered during the tests, including acetylcholine, epinephrine, and norepinephrine, radioactive chemicals used in imaging studies, and drugs that affect blood vessels, heart rate, and force of heart contractions.

syncope prediction on tilt table

For a number of years, researchers have examined the effects of the muscle-tensing technique, Applied Tension (AT), on blood donation-related vasovagal symptoms and donor retention. AT was developed originally to reduce symptoms and avoidance behaviour in people with strong fears of blood and needles (phobics). It was based on the idea that exercise-related increases in blood pressure might be able to counteract the effects of stimuli that lead to a decrease in delivery of blood to the brain. AT was adapted for non-phobic blood donors and significant reductions in self-reported vasovagal symptoms and the need for nurse-initiated treatment as well as increases in donor retention were observed in some groups. That said, individual response to AT is quite variable. This is probably related to recent research indicating that exercise-related maintenance of heart rate and blood pressure plays only a minor role in reducing vasovagal symptoms. Rather, AT appears to be working at least in part by regulating breathing and reducing the possibility of hyperventilation. Pilot results suggest that a novel intervention aimed specifically at breathing may be more effective and reliable than traditional AT. To evaluate this idea, 408 blood donors at mobile clinics in colleges and universities will be assigned randomly to four conditions. In brief, 5-minute preparation sessions using a notebook computer, donors will either learn a respiration control technique to avoid hyperventilation, AT, both, or neither. As a manipulation check and also a means of examining mechanisms of the interventions, e.g., the possibility that AT may work by regulating breathing and CO2, participants will wear non-invasive portable capnometers while they are giving blood. Outcome will also be assessed by self-report of vasovagal symptoms, observational data, and number of return visits to a blood clinic in the following year verified by the provincial blood collection agency, Héma-Québec. As a secondary aim, the research will examine possible moderating effects of pre-donation anxiety and sex. The development of simple, effective approaches to reduce vasovagal symptoms during blood donation has the potential to improve the blood donation experience and blood donor retention as well as encourage people who have never given blood to consider the procedure. It will also improve medical and dental care more generally given the use of needles in so many procedures.

To characterize the impact of orthostatic hypotension (OH) and reflex syncope on signals measured using a wearable cardiac monitor prototype device. To evaluate the relationship of signals measured from the wearable cardiac monitor prototype device with reported symptom severity of orthostatic intolerance per standard data collection, analysis, and questionnaires.

Patients's demographics and perioperative factors affect the occurrence of hypotensive bradycardic events in the patients undergoing arthroscopic shoulder surgery in the sitting position under interscalene block.

This study will evaluate the correlation between the respiratory rate derived from the Reveal Insertable Cardiac Monitor (ICM) electrocardiogram (ECG) with the respiratory rate obtained from an external respiratory band in patients previously implanted with a Reveal for unexplained syncope or suspected arrhythmia.

This study´s aim is to explore physiological associations concerning pulse wave velocity, heart rate and blood pressure in order to make taking the blood pressure more comfortable.

The aim of SYNCAT study is to study the level of adherence of the centers in Cataluña tu the Syncope Guidelines ESC2009 for the diagnosis and treatment of syncope and the impact that following them can have in the prognosis of these patients.

The purpose of this study is to perform a prospective evaluation of the vasovagal syncope prediction algorithm, called Tilt Test Analyzer, during head up tilt testing tests in one center in the United Kingdom.

The aim of this study is to evaluate the incidence and status of urgent medical conditions. After defining the urgent situations, the investigators will evaluate the adequacy of the standard medical kits and trainings.