View clinical trials related to Syncope.
Filter by:Comparing the arrhythmia diagnostic yield of MCOT as compared to standard loop event monitors in patients presenting with palpitations, syncope or near syncope occurring less frequently than every 24 hours. Patients randomized and are enrolled for 30 days. Prior testing required: 24 hours of non diagnostic monitoring,
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 purpose of this study is to test specific device programming in patients without a previous history of a life-threatening, abnormally fast heartbeat who are implanted with a Medtronic ICD (Implantable Cardioconverter Defibrillator) or ICD with CRT (Cardiac Resynchronozation Therapy) device. The information learned from this study could be used to guide physicians in future ICD or CRT device programming.
The purpose of this study is to determine whether eight weeks of exercise performed at an intensity of approximately 65% VO2max will improve symptoms associated with fainting (vasovagal syncope).
This is a prospective, controlled, opened randomized study to evaluate the cost benefit of a primary implantation of a loop recorder versus the conventional diagnostic cascade for syncope most likely due to cardiac arrhythmia.
Beneficial effect of chronic hydration with salt supplementation in patients with recurrent unexplained syncope is not established. We sought to determine if chronic oral rehydration with salt supplementation improved the tolerance and hemodynamic responses of patients with unexplained recurrent syncope.
This is a multi-center, prospective, observational study enrolling 400 patients with suspected or certain neurally-mediated syncope, who undergo carotid sinus massage, tilt testing and Implantable Loop Recorder (ILR)implantation. In its second phase, which starts after the first ILR-documented syncope, the study will register the patient outcome after administration of ILR-guided therapy, which is left to the discretion of the physicians. The main objective is to verify the value of ILR in assessing the mechanism of syncope and the efficacy of the ILR-guided therapy after syncope recurrence.
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 examine whether certain procedures that do not involve the use of medications can reduce symptoms of neurocardiogenic syncope (SIN-ku-pe), or a condition involving recurrent fainting. This condition is also known as vasovagal syncope or neurally mediated hypotension. Neurocardiogenic syncope is a disorder of the autonomic nervous system, which controls automatic body functions such as blood pressure, heart rate, and sweating. That system can be affected by medications, conditions of the mind or body, and by a person's surroundings. Researchers in this study wish to learn whether hypnosis, hand exercises, education, or diary keeping can affect the autonomic nervous system and improve symptoms of neurocardiogenic syncope. Patients age 18 or older who have neurocardiogenic syncope may be eligible for this study. Those who have a medical illness making it unsafe to participate, who cannot discontinue certain medications, or who are pregnant are not eligible. Patients will undergo a medical history and physical examination, complete a questionnaire, and experience Valsalva and tilt table tests. These tests will take about 5 hours during 1 to 2 days. The Valsalva test evaluates some of the reflexes of autonomic nervous system. Patients will lie flat on a padded table and have sensors placed on the body, to measure blood pressure, breathing rate, and other functions. They will blow into a sterile tube for 12 seconds while the body's responses are measured. The procedure may need to be repeated several times. During the test, an intravenous tube, guided by a needle, will be placed in the patient's arm. The tube will be used to collect samples of blood (less than 7 tablespoons) to measure chemicals such as adrenaline. For the tilt table test, a patient will lie on a padded, motorized table and have sensors placed on the body. Velcro straps will be placed around the patient's body to help hold him/her on the table. Then the table will tilt the patient from a flat position to an upright one in about 10 seconds. The patient will stay upright for 45 minutes while symptoms are monitored, measurements are taken, and blood samples are collected through the intravenous tube. Then the table will be returned to the flat position. If the patient faints or is about to faint, or if he or she has an unsafe heart rhythm before the 45 minutes is over, the test will be stopped and the table will be returned to the flat position. Symptoms will be treated as needed. Patients who qualify for further study will then become familiar with hypnosis and be evaluated for their natural ability for experiencing it. A professionally trained doctor will guide patients into a hypnotic state, and patients will be asked to respond to various suggestions. They will be videotaped, an activity that will require a separate consent form. Following these procedures, patients will be assigned to one of the four groups in this study. Those in the hypnosis group will have weekly sessions for 6 weeks, with each session lasting about 1-1/2 hours. The education group will meet a study investigator for learning about syncope and the autonomic nervous system, with each session lasting about 1-1/2 hours once a week for 6 weeks. The hand exercise group will be taught certain hand exercises to perform, at home and as instructed, for 6 weeks. The diary group will receive instructions on keeping a diary pertaining to their condition, at home, for 6 weeks. After 6 weeks, patients will return for an evaluation to include completion of questionnaires and another tilt table test and blood collection by intravenous tube. This entire study will take about 8 weeks. There may be direct benefits from participating in this study. The experimental procedures may help patients' neurocardiogenic syncope. After completing this study, patients will be offered any or all of the experimental procedures tested in this study upon their request and at the discretion of the principal investigator. For example, a patient who is assigned to the diary group may be offered hypnosis, education, and hand exercise instruction after completion of the study.
This study will examine the effectiveness of the drug propranolol in preventing fainting in patients with sympathoadrenal imbalance (SAI). SAI is a particular pattern of nervous system and chemical responses in which the blood vessels in skeletal muscles do not remain constricted appropriately during standing for a long time. This can lower blood pressure and cause fainting. Propranolol (Inderal® (Registered Trademark)) is a Food and Drug Administration-approved drug that belongs to a class of drugs called beta-blockers. These drugs slow the heart rate and maintain blood pressure in certain situations. Children between 10 and 17 years of age with frequent fainting or near-fainting due to SAI may be eligible for this study. Children must experience severe dizzy episodes at least once every 2 months or fainting episodes at least once every 4 months. The condition must be severe enough to affect the child's quality of life or to have forced the child to alter his or her life routines to accommodate to the illness. Screening includes a tilt table test, described below, to determine if the child has a particular chemical pattern in the blood. Children enrolled in the study take propranolol pills in increasing doses during the first week of the study to determine the proper dose for the individual. Then, the drug is stopped until the experimental phase of the study begins. In this phase, children are randomly assigned to take either propranolol or placebo (a look-alike pill with no active ingredient) for a maximum of 3 days. On the fourth day, the child undergoes a tilt table test to determine whether the treatment affects his or her ability to tolerate tilt. For this test, the child lies on a padded table with a motorized tilt mechanism that can move the child from a flat position to an upright position in about 10 seconds. The child remains upright for up to 40 minutes while the following measurements are taken: - Blood sampling: Blood is drawn through a catheter (thin plastic tube) placed in an arm vein. This allows repeated sampling without repeated needle sticks. Samples are collected before starting the tilt test, about every 4 minutes during the test, immediately when a drop in blood pressure is detected or symptoms develop, and after 10 minutes of recovery lying flat. A maximum of 12 samples are collected for each tilt test. - Physiologic measurements: Blood pressure, heart rate, and electrocardiogram (EKG) are measured continuously during the tilt test session, and blood flows and skin electrical conduction are measured intermittently. Blood flow is measured using sensors applied to the skin and a blood pressure cuff around the limb. For skin blood flow measurements, a laser beam scans the skin surface. The skin electrical conduction test measures how well the skin conducts electricity. This is measured through sensors placed on the tips of two fingers. Respiration and breathing rate are monitored by an elastic cloth band around the chest. - Self-report questionnaires: Patients or their parents complete a questionnaire about the child's symptoms before and during treatment. The effects of the test drug are allowed to wear off for up to 1 week, after which the entire tilt test procedure is repeated. Patients who were given propranolol for the first test session take placebo for the repeat session, and those who were given placebo take propranolol.