Vasovagal syncope

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BACKGROUND: Both the adrenergic and renin-angiotensin systems contribute to orthostatic circulatory homeostasis, which is impaired in postural orthostatic tachycardia syndrome (POTS). Activating autoantibodies to the α1-adrenergic and β1/2-adrenergic receptors have previously been found in sera from patients with POTS. We hypothesized that patients with POTS might also harbor activating autoantibodies to the angiotensin II type 1 receptor (AT1R) independently of antiadrenergic autoimmunity...

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AIM: This study examined the total peripheral vascular resistance (TPVR) and cardiac output changes due to the head-up tilt test (HUTT) in children with vasovagal syncope (VVS). METHODS: From December 2013 to January 2016, we recruited 77 children diagnosed with VVS group at Peking University First Hospital, China, and 28 children without VVS provided the control group. Heart rate, blood pressure, TPVR, cardiac output and baroreflex sensitivity were monitored during the HUTT...

BACKGROUND: Vasovagal syncope is the most common cause of syncope in children and adults, accounting for 50-66% of unexplained syncope. There are no studies establishing the relationship between syncope, baseline heart rate, and blood pressure. OBJECTIVE: To identify a possible association between baseline blood pressure and heart rate with syncope. DESIGN/METHODS: We conducted a questionnaire-based chart review study. A questionnaire was distributed to the guardian of children between eight and 18 years of age who attended the Pediatric Ambulatory Care Clinic at Flushing Hospital Medical Center...

BACKGROUND: Vasovagal syncope (VVS) is characterized by hypotension and bradycardia followed by lowering of cerebral blood flow. Remote limb ischemic preconditioning (RIPC) is well documented to provide cardio- and neuroprotection as well as to improve cerebral blood flow. We hypothesized that RIPC will provide protection against VVS-induced hypotension, bradycardia, and cerebral hypoperfusion. Second, because endothelial nitric oxide synthase has been reported as a mediator of cerebral blood flow control, we hypothesized that the mechanism by which RIPC primes the vasculature against VVS is via the α1 -adrenoceptor-protein kinase Cε-endothelial nitric oxide synthase pathway...

Purpose: Syncope is a common condition affecting almost one-third of the general population. The present study measures the prevalence of psychiatric traits in patients presenting with syncope (unexplained and vasovagal) and whether recurrent attacks have an impact on psychiatric profiles. Patients and methods: This is a case-control study in a tertiary hospital enrolling all patients aged ≥12 years with single or recurrent syncopal attacks. A self-reporting psychometric questionnaire (The Symptoms Checklist-90-Revised) was used to screen for depression, anxiety, somatization disorder, and phobia...

Enhanced parasympathetic tone may cause sinus bradycardia or pauses, transient or permanent atrioventricular block, with resultant vasovagal syncope. A substantial portion of these patients may be highly symptomatic and refractory to the conventional therapies and may require cardiac pacemaker implantation. Cardioneuroablation is a little known technique for management of patients with excessive vagal activation based on radiofrequency catheter ablation of main parasympathetic autonomic ganglia around the heart...

Cognitive and emotional processes are influenced by interoception (homeostatic somatic feedback), particularly when physiological arousal is unexpected and discrepancies between predicted and experienced interoceptive signals may engender anxiety. Due to the vulnerability for comorbid psychological symptoms in forms of orthostatic intolerance (OI), this study investigated psychophysiological contributions to emotional symptomatology in 20 healthy control participants (13 females, mean age 36 ± 8 years), 20 postural tachycardia syndrome (PoTS) patients (18 females, mean age 38 ± 13 years) and 20 vasovagal syncope (VVS) patients (15 females, mean age 39 ± 12 years)...

We described the clinical evolution of patients with structural heart disease presenting at the emergency room with syncope. Patients were stratified according to their syncope etiology and available scores for syncope prognostication. Cox proportional hazard models were used to investigate the relationship between etiology of the syncope and event-free survival. Of the 82,678 emergency visits during the study period, 160 (0.16%) patients were there due to syncope, having a previous diagnosis of structural heart disease...

OBJECTIVE: In this study we aimed to predict the time to syncope occurrence (TSO) in patients with vasovagal syncope (VVS), solely based on measurements recorded during the supine position of the head-up tilt (HUT) testing protocol. METHODS: We extracted various time and frequency domain features related to morphological aspects of arterial blood pressure (ABP) and the electrocardiogram (ECG) raw signals as well as to dynamic interactions between beat-to-beat ABP, heart rate, and cerebral blood flow velocity...

BACKGROUND: Psychogenic pseudo-syncope (PPS) frequently mimics syncope. The aim of this study was to assess the prevalence and clinical features of PPS and its relationship to vasovagal syncope (VVS). METHODS: We examined retrospectively the medical records of 1401 consecutive patients referred to a syncope unit. We identified patients who had the final diagnosis of PPS. In these patients, we retrieved the initial diagnosis made during their first visit and the subsequent tests performed leading to the final diagnosis...

: The purpose of this two-part consensus document is to provide specific suggestions (based on an extensive literature review) on appropriate pacemaker setting in relation to patients' clinical features. In part 2, criteria for pacemaker choice and programming in atrioventricular blocks and neurally mediate syncope are proposed. The atrioventricular blocks can be paroxysmal or persistent, isolated or associated with sinus node disease. Neurally mediated syncope can be related to carotid sinus syndrome or cardioinhibitory vasovagal syncope...

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Non-pharmacological therapies, especially the physical maneuvers, are viewed as important and promising strategies for reducing syncope recurrences in vasovagal syncope (VVS) patients. We observed the efficacy of a modified Valsalva maneuver (MVM) in VVS patients. 72 VVS patients with syncope history and positive head-up tilt table testing (HUTT) results were randomly divided into conventional treatment group (NVM group, n = 36) and conventional treatment plus standard MVM for 30 days group (MVM group, n = 36)...

PURPOSE: Individuals predisposed to vasovagal syncope may have different autonomic nervous system control mechanisms from those without predisposition to vasovagal events. To test this hypothesis, we investigated different sympathetic responses in a canine model of vasovagal syncope. METHODS: Left thoracotomy was performed on 20 mongrel dogs. The heart was exposed and a bolus of veratridine (15 μg/kg), a neurotoxin which prevents the inactivation of sodium ion channels, was injected into the left atrium to induce a Bezold-Jarisch reflex-mediated vasovagal event, characterized by bradycardia, decreased inotropism, and hypotension...

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No abstract text is available yet for this article.

Predictive coding models, such as the 'free-energy principle' (FEP), have recently been discussed in relation to how interoceptive (afferent visceral feedback) signals update predictions about the state of the body, thereby driving autonomic mediation of homeostasis. This study appealed to 'interoceptive inference', under the FEP, to seek new insights into autonomic (dys)function and brain-body integration by examining the relationship between cardiac interoception and autonomic cardiac control in healthy controls and patients with forms of orthostatic intolerance (OI); to (i) seek empirical support for interoceptive inference and (ii) delineate if this relationship was sensitive to increased interoceptive prediction error in OI patients during head-up tilt (HUT)/symptom provocation...

Ganglionated plexi (GP), consisting of conglomerations of autonomic ganglia on the epicardial surface of the heart, have been shown to play a significant role in different arrhythmias, including atrial fibrillation. GP ablation has become an adjunctive procedure in the treatment of atrial fibrillation, while it has been used successfully in preliminary studies in vasovagal syncope. This review will present the current data on the physiology and clinical applications of GP ablation in the treatment of atrial fibrillation and other diseases...