View clinical trials related to Syncope.
Filter by:Investigate clinical effects (reduction of number of syncope and associate symptoms) of suspension of vasoactive drugs in patients affected by vasodepressor reflex syncope.
This study is intended to compare the new Carnation Ambulatory Monitoring (CAM) System, a patch monitoring system, with the Holter monitoring system. Holters represent the current standard for continuous recording of the ECG over extended periods.
Syncope affects about 50% of Canadians, is the cause of 1-2% of emergency room visits, and probably is responsible for CDN $250 million in health care spending each year. It is associated with decreased quality of life, trauma, loss of employment, and limitations in daily activities. The most common cause is vasovagal syncope. This occurs in people of all ages, and is a lifelong predilection. While the median number of faints in the population is 2, those who come to the investigators care have a median 10-15 lifetime spells, and have an increased frequency in the year before presentation. Vasovagal syncope is due to abrupt hypotension and transient bradycardia, which cause cerebral hypoperfusion. The pathophysiology may be either failure of venous return or progressive vasodilation, both due to inappropriately low sympathetic outflow. Sympathetic stimulation might be involved early in the reflex cascade. There is no known medical treatment for frequent fainting. The investigators performed the pivotal CIHR-funded randomized trials that showed that neither permanent pacing, beta blockers, nor fludrocortisone help the majority of patients. However 3 observational studies suggested that beta blockers prevent syncope in older subjects, and the Prevention of Syncope Trial (POST1) showed in a prespecified, -stratified analysis that patients ≥42 years tended to benefit. The investigators recent meta-analysis showed a benefit from metoprolol in these patients, with a hazard ratio of 0.52 (CI 0.27 to 1.01), and an age-specific response to beta blockers (p = 0.007). These results suggest the need for a randomized clinical trial of metoprolol for the prevention of vasovagal syncope in older subjects. Accordingly,the investigators conducted a poll of 48 cardiologists and neurologists in Canada and abroad: 98% stated that a randomized trial was necessary, and 92% agreed to participate in such a trial. Separately, this study emerged as the first choice for syncope randomized trials after consultation with Canadian and international experts. Objective: To determine if treatment with metoprolol in patients ≥40 years old with moderate to severely frequent vasovagal syncope will better suppress syncope recurrences than placebo. Methods: This will be a longitudinal, prospective, parallel design, placebo-controlled, randomized clinical trial. Patients will be enrolled during a recruitment period of 4 years and followed for a fixed period of 1 year. Subjects will have had ≥1 faint in the previous year, and a diagnosis of vasovagal syncope based on a quantitative diagnostic score. They will be randomized to receive either metoprolol or placebo at an initial dose of 50 mg bid. Dose adjustments will be made according to treating physician discretion to optimize tolerance and compliance while maximizing dose. The primary outcome measure will be the time to the first recurrence of syncope (after a 2 week dose titration wash-in period) over the 1-year observation period. The primary analysis will be performed on an intention-to-treat basis. Secondary analyses will include an on-treatment analysis, as well as analyses comparing syncope and presyncope frequency, number needed to treat, quality of life, impact of syncope on daily living, and cost from the perspective of the publicly funded health care system. The investigators will enroll 248 patients to have an 85% power to detect a reduction (p<0.05) in the primary outcome from 50% (placebo group) to 30% (midodrine group), a 40% relative risk reduction. This sample size also allows for a 11% rate of subject dropout with loss to follow-up before a syncopal event. The University of Calgary Syncope Clinic has a well-functioning clinical trial apparatus that successfully completed the randomized, multicenter Prevention of Syncope Trials (POST1: metoprolol for vasovagal syncope; POST2: fludrocortisone for vasovagal syncope) and SIRCAT (Statin-Induced Reduction of Cardiomyopathy Trial). Enrolment is underway in the CIHR-funded POST3 (pacing versus loop recorders in syncope patients with bifascicular block) and POST4 (midodrine for vasovagal syncope). Study centres that were highly productive in POST1-4 have agreed to participate. The investigators therefore will have ample syncope enrolling centres. Relevance: This study will provide evidence to inform the use of metoprolol in the treatment of moderate to severely frequent syncope in older patients with vasovagal syncope. Given the lack of any other conventional medical therapy the investigators expect it to have rapid impact on care.
The investigators' hypothesis is that dysregulation of autonomic function, as revealed during a simulated dive reflex, may result in an attenuation of the heart rate response to a greater degree in asthmatics who collapse during exacerbations of asthma than that seen in healthy individuals and in asthmatics without a history of syncope. The investigators will test this by assessing autonomic function through a dive reflex protocol.
Blood donation is a generous act carried out by healthy male and female volunteer donors. The safety of blood donation in France is based on rigorous well documented biological and medical criteria, in particular concerning the volume of blood to be taken. While whole blood donation is very safe, some donors experience faintness during or after donation. Any injury resulting from a fall increases its seriousness, especially when it happens outside the donation site. According to various studies, adverse reactions are experienced by between 0.28% and 2.72% of all donors and occur in all categories (sex and age). A retrospective evaluation of the frequency of faintness incidents on during whole blood donation over 2012 in the Rhone Alpes' region of France shows a frequency ranging from 1.05% in mobile donation units in towns to 4.24% in donation units in high schools, with no reporting of delayed incidents of faintness by this donor population.
This study is intended to compare the new Carnation patch monitoring system with the Zio patch, which represents the current standard for continuous recording of the ECG over extended periods.
The essential arterial hypotension and allostasis registry is a prospective, observational research that has the purpose of demonstrating that essential blood pressure (BP) disorders and the associated comorbidities are a result of the inappropriate allostatic response to daily life stress. This required a functioning brain orchestrating the evaluation of the threat and choosing the response, this is a mind-mediated phenomenon. If the response is excessive it contributes to high BP, if deficient to low BP, and the BP itself will identify the allostatic pattern, which in turn will play an important role in the development of the comorbidities. To do so, consecutive patients of any age and gender that visit a cardiologist's office in Medellin, Colombia, are recruited. Individuals are classified according to their arterial BP and allostasis and follow them in time to see what kind of diseases develops the most (including BP) in the follow up according to the categorization of the characteristic chosen and after adjustment for confounder's variables. In addition, stress events with their date are registered. HYPOTHESIS The causes of the diseases are multifactorial. Physical, biochemical, psychological, social, and cultural dimensions of development dynamically interact to shape the health development process. A person´s health depends on their: 1. Biological and physiologic systems 2. External and internal environment (a) physical, b) internal behavioural and arousal state as registered by the brain. 3. Their interaction. The allostatic mechanisms to the internal and external stressors (allostatic load) involves a network composed by: 1. Functional systems; mediated by: 1. The Autonomic Nervous System 2. The endocrine system 3. The immune system 2. Structural changes: whenever the internal and/or external stressors are long lasting and/or strength enough, they may induce changes in: 1. Epigenetic, endophenotypes, polyphenism. 2. Plasticity 3. The interaction between a) and b). The network response do not affect exclusively the BP, propitiating the development of comorbidities, which may prompt strategies for prevention, recognition and ultimately, treatment. The allostatic model defines health as a state of responsiveness. The concept of psycho-biotype: The allostasis is the result of both: biological (allostasis) and psychological (psychostasis) abilities. It is proposed that both components behave in similar direction and magnitude. Immune disorders may be associated with the development of cancer. High BP population has a higher sympathetic and lower vagal tone, this has been associated with a decrease in the immune´s system function. Resources and energy depletion: Terms like weathering have been used to describe how exposures to different allostatic loads gradually scrape away at the protective coating that keeps people healthy. It is postulated that High BP individuals have more resources and energy.
The purpose of this study is to evaluate the effectiveness of cardioneuroablation for the treatment of neurocardiogenic syncope (NCS), also known as "vaso-vagal" syncope. Syncope is a general term for passing out spells and neurocardiogenic syncope is a specific form of passing out spells caused by sudden drops in heart rate or blood pressure. Although the specific mechanisms of NCS are not well understood, it is believed that some people are prone to developing passing out spells in specific situations such as standing up for a long period of time, pain or nausea. In these situations, the body reacts with a paradoxical reflex which leads to a drop in blood pressure and heart rate and causes passing out. Certain types of medications are used to treat NCS including beta-blockers, midodrine and florinef, among others. However, none of these medications are particularly effective at preventing passing out spells and many people continue to have episodes despite trying different medications. Cardioneuroablation is a new form of treatment for NCS. The term ablation means using a wire to make small electrical burns in the heart. Ablation has been used for many years to treat other electrical disturbances in the heart but the use of ablation to treat NCS is a new application. The goal of cardioneuroablation is to identify areas within the heart which are believed to initiate the reflex which triggers the drop in heart rate and blood pressure that leads to passing out. In preliminary studies, it has been suggested that cardioneuroablation may be significantly more effective than medications at preventing passing out spells for people with NCS. Hypothesis: Cardioneuroablation of vagal inputs in the left atrium may serve as an effective treatment modality for the prevention of NCS by blunting the initial trigger of the cascade that leads to symptoms and syncope.
The purpose of the Reveal LINQ Usability Study is to assess the functionality of the Reveal LINQ insertable cardiac monitor and accompanying system in patients indicated for an insertable cardiac monitor
Patients with the symptom complex syncope or near-syncope are quite often in the emergency department. Most patients with syncope have a positive prognosis. However some types of syncope are associated with an increased morbidity and mortality. It is a challenge to detect these patients reliably at an early stage. The current guidelines contain exact definitions concerning the characteristics of patients with syncope and recommendations on how to diagnose and treat these patients following standardized pathways. Due to the fact that near-syncope is poorly defined and therefore seldom evaluated in clinical trials, data concerning near-syncope are rare. Our aim was to characterize patients presenting with syncope or near-syncope to the emergency department regarding their risk profile, comorbidities and prognosis. First we evaluated if there is a difference between the two groups syncope and near-syncope concerning type and frequency of adverse events. Furthermore we analyzed the routinely measured cardiac biomarkers NT-proBNP and hs cTnT in patients with syncope or near-syncope. Then we determined both their prognostic accuracy in predicting adverse events and their diagnostic accuracy in finding the underlying etiology. Finally we analyzed a special patient collective, patients aged ≥ 65 years. It is assumed that elderly patients are suffering from comorbidities and age-related physiological and cognitive disabilities. We therefore hypothesize that elderly patients, in contrast to patients aged < 60, display an increased risk of adverse events and that they have a poorer prognosis.