View clinical trials related to Syncope.
Filter by: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.
Cardioinhibitory neurocardiogenic syncope (CNS) or vasovagal syncope, is the most frequent aetiology of syncope in young people without apparent cardiac or neurological pathology. It is usually caused by inappropriately trigger-activated cardiac reflex which finally precipitates asystole, sinus bradycardia, or atrioventricular (AV) block [1]. Despite young patients affected by CNS have an excellent prognosis when electro-structural heart diseases are excluded [2], their quality of life may be seriously affected by recurrent episodes [2, 3]. Cardiac pacing might help to control symptoms and therefore is considered in patients aged more than 40 years old with recurrent episodes and documented cardioinhibitory response [1, 4]. In young individuals, the role of cardiac pacing is dubious due to predicted frequent device substitutions and adverse ventricular remodeling over time. Recently, radiofrequency (RF) biatrial ablation of ganglionated plexi (GP) has showed promising results in the short and long-term treatment of reflex syncope, functional atrioventricular block, or sinus node dysfunction [5, 6]. Nonetheless, strong evidences are emerging about efficacy of transcatheter ablation limited to ganglionated plexi in the right atrium with the possibility to avoid side-effects related to left-sided procedures [6] Aim of study To evaluate in a large cohort of patients effectiveness and safety of gangliar transcatheter ablation in the right atrium to obtain atrial denervation and prevent CNS. Study population and methods Twenty consecutive patients affected by cardioinhibitory neurocardiogenic syncope will be enrolled in the study. Inclusion criteria: - age between 18 and 60 years - 3 syncopal episodes at least of likely CNS in the previous 2 years - marked cardioinhibitory response to HUT or documented asystolic pauses at internal loop recorder registration [7]. Cardioinhibition will be considered as elicitation of asystolic pause (sinus arrest or AV block) ≥ 3 seconds associated to syncope or ≥ 6 seconds and related presyncope. Exclusion criteria: - documented myocardial and/or valvular abnormalities on 2D echocardiogram (ejection fraction lower than 50%) - documented tachyarrhythmias as possible causes of symptoms - channelopathies (Brugada syndrome, LQT or SQT syndrome) - ventricular preexcitation - symptomatic orthostatic hypotension diagnosed by standing blood pressure measurement - pregnancy in women - previous cardiac pacemaker implantation. After obtaining informed consent patients will undergo to basal electrophysiological study (EPS) to record AH interval, HV interval, Wenckebach cycle length, sinus node recovery time (SNRT) and correct sinus node recovery time (cSNRT); the same parameters will be recorded immediately after ablation. Following basal EPS an accurate (200 valid points at least) electroanatomic right atrium mapping (CARTO 3™ Biosense Webster, Inc) will be performed and subsequently radiofrequency delivered at right atrial anatomic sites where the underlying presence of ganglionated plexi (GPs) clusters was regarded as highly probable, on the basis of anatomical studies [8-11]: the supero-posterior area (superior right atrial GP, adjacent to the junction of the superior vena cava and the posterior surface of RA), the middleposterior area (posterior right atrial GP, posterior surface of the RA adjacent the interatrial groove), the infero-posterior area (inferior right GP placed between the inferior vena cava, coronary sinus ostium, and near the atrioventricular groove). Transcatheter ablation will be performed using an 8mm-tip catheter (Biosence-Webster Navistar DS 8mm) or an irrigated 4 mm-tip catheter with force control system (Biosence Webster Smarttouch). Ablation will be performed until complete elimination of local atrial electrical activity. Response to radiofrequencies delivery will be considered successful in case of asystolic pause or cardiac cycle lengthening of 30% (compared to basal cycle) at least. To prolong RF delivery despite asystolic response, a quadripolar catheter will be positioned in right ventricle to backup stimulation. To avoid phrenic nerve injury, high amplitude stimulation will be performed just before radiofrequency delivery to the superior right atrial GP. HRV analysis will be performed on admission, at 2 hour after ablation and patients discharge. The HRV analysis will include the following parameters: mean, maximal and minimal heart rate, SDNN (standard deviation of Normal-Normal), RMSSD (root mean square successive difference), pNN50 (percentage of differences between adjacent N-N intervals that are >50 msec), LF (low frequency), HF (high frequency). Moreover, an HUT and an HRV analysis will be performed at 1, 3, 6 and 12 months after ablation procedure during the follow up.
Syncope (temporary loss of consciousness) is a frequent reason for an emergency department (ED) visit among older adults. The current ED evaluation of syncope frequently leads to hospitalization, results in low diagnostic yield, and is enormously costly. The purpose of this protocol is to improve risk prediction for syncope. Improved risk prediction will inform the design of interventions to safely reduce unnecessary health service use. This is a multi-center, prospective, observational cohort study of older (age≥60 years) adults who present to an emergency department with syncope (otherwise known as fainting). The primary outcome is a composite of 30-day cardiac death and serious cardiac events. Study Aims and Hypotheses are: Specific Aim 1. Describe serious outcomes after unexplained syncope; rates and reasons for admission; and frequency, diagnostic yield, and therapeutic impact of inpatient diagnostic tests. H1: Current patterns of care representing a diversity of practice settings and patient populations are costly with low clinical benefit. Specific Aim 2. Derive and validate a novel risk prediction model for 30-day cardiac death and serious cardiac outcomes after unexplained syncope. H2: Explicit criteria including contemporary cardiac biomarkers will improve risk stratification compared to unstructured physician assessment and published risk models. Specific Aim 3. Assess safety and costs of a risk-tailored diagnostic algorithm compared to existing care for unexplained syncope. H3: A risk-tailored diagnostic algorithm can safely reduce the costs of evaluating unexplained syncope in older adults.
All patients consecutively referred with the first episode of transient and short-lasting loss of consciousness will have a diagnostic workup for the assessment of the most common causes of syncope, and will be evaluated for the presence of pulmonary embolism (PE) with the use of an internationally accepted algorithm including a pre-test clinical probability (PTP according to the method of Wells et al.) and a high-sensitivity quantitative D-dimer assay. If the PTP is low and D-dimer negative, PE will be excluded. All other patients will undergo confirmatory diagnostic tests (either computerized tomography or ventilation/perfusion lung scanning) in order to confirm or rule out the presence of PE.
Postural orthostatic tachycardia syndrome (POTS) is a common cause of orthostatic intolerance in adolescents and adults. Compression stockings are commonly recommended as a treatment modality for POTS, but the effects of abdominal and lower extremity compression during tilt table testing have not been measured in adolescent patients. The aims of our study are to compare heart-rate changes and symptom onset during tilt table testing (a) with and without abdomen/lower extremity compression and (b) with abdominal compression only versus lower extremity compression only. During phase 1, 20 adolescents with POTS will undergo up to 10 minutes of tilt without compression (trial #1), a repeat study of up to 10 minutes with full compression (trial #2), and a third study without compression up to 10 minutes (trial #3). Compression will be performed using the non-inflatable Zoex anti-shock garment. During study phase 2, an additional 20 adolescent POTS patients will undergo up to 10 minutes of tilt without compression (trial #1), a repeat study of up to 10 minutes with abdominal compression only [n=10] or lower extremity compression only [n=10] (trial #2), and a third study repeated without compression up to 10 minutes (trial #3). To limit compression to the abdomen only, we will use the Zoex garment strap numbers 4 and 5 (thigh and abdomen) without straps 1-3 (lower extremities). For lower extremity-only compression, we will use Zoex garment straps 1-4 (lower extremity and thigh) without strap 5. Data collected will include mean and peak heart rates and timing of symptoms with each trial. A paired-samples t-test will be used to compare mean heart rates between trials for each study phase. Hazard analyses will be used to assess time-based endpoints.
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.
Syncope is a common problem that many clinicians may encounter in various outpatient settings. Neurocardiogenic syncope (NCS) is a benign condition characterized by a self limited episode of systemic hypotension. Patients are usually managed with education on syncope, anxiety management, and coping skills. It has been established that practice of Yoga could relieve stress and anxiety. In a different study, they also found that Yoga positively influences cardiovascular function by decreasing the heart rate and blood pressure. The main objective of Yoga is to achieve control over the autonomic nervous system and able to control functions like heart rate, blood pressure and respiratory rate. Based on the findings that Yoga relieves stress and reduces heart rate, the investigators propose to study if Yoga can decrease the frequency of NCS and also reduce the symptoms associated with these episodes.
Dysautonomia, primarily defined as postural orthostatic tachycardia syndrome (POTS) can seriously disrupt a child's daily activities. It is most commonly associated with nausea or abdominal pain. In preliminary studies, when orthostatic intolerance was treated with fludrocortisone, a standard therapy for orthostatic intolerance (OI), symptomatic improvement in nausea was observed. However, children with POTS were also observed to have higher supine mean arterial pressure (MAP) (preliminary data) and greater suppression of the baroreceptor reflex sensitivity (BRS) occurred upon up-right tilt. While fludrocortisone alleviates nausea associated with OI, its long-term use may pose long term health risks to children including worsening hypertension. Therefore, it is the objective of this study to define the mechanism for OI as it relates to nausea. The investigators hypothesize that OI resulting from changes in the autonomic nervous system is the likely mechanism for the nausea observed in the patients in this study. The investigators further hypothesize that this is potentially an early marker for future cardiovascular problems such as early onset hypertension and cardiac hypertrophy. The general objective of this protocol is to address this gap in knowledge by determining the autonomic characteristics of children with OI as well as defining neurohumoral profiles for these subjects to better understand the cause of the elevated supine in these subjects. By better understanding the potential mechanism for this condition, it is the investigators future goal to develop a more focused and safer treatment strategy. The investigators will study subjects between 10 to 18 years of age utilizing the tilt table to mimic daily life stressors and also measure serum levels of epinephrine, norepinephrine, rennin, angiotensin II, aldosterone, and vasopressin at baseline and during tilt. This study will generate data with high impact in that more rational treatments for management of dysautonomia could be chosen on the basis of the profile of dysautonomia and neurohumoral markers.
Study hypothesis: Dual-chamber pacemaker therapy with rate-hysteresis features is effective in preventing syncopal recurrences in patients affected by cardioinhibitory (CI) forms of reflex syncope diagnosed by means of carotid sinus massage, tilt table testing or implantable loop recorder (ILR). The outcome is measured either by the time to first syncopal recurrence or the total syncope burden.
The purpose of this study is to determine whether or not the intravenous adenosine test readily identifies patients with unexplained syncope who would benefit from permanent pacemaker implantation.