Vagal sensory neurons mediate the Bezold-Jarisch reflex and induce syncope.

Visceral sensory pathways mediate homeostatic reflexes, the dysfunction of which leads to many neurological disorders1. The Bezold-Jarisch reflex (BJR), first described2,3 in 1867, is a cardioinhibitory reflex that is speculated to be mediated by vagal sensory neurons (VSNs) that also triggers syncope. However, the molecular identity, anatomical organization, physiological characteristics and behavioural influence of cardiac VSNs remain mostly unknown. Here we leveraged single-cell RNA-sequencing data and HYBRiD tissue clearing4 to show that VSNs that express neuropeptide Y receptor Y2 (NPY2R) predominately connect the heart ventricular wall to the area postrema. Optogenetic activation of NPY2R VSNs elicits the classic triad of BJR responses-hypotension, bradycardia and suppressed respiration-and causes an animal to faint. Photostimulation during high-resolution echocardiography and laser Doppler flowmetry with behavioural observation revealed a range of phenotypes reflected in clinical syncope, including reduced cardiac output, cerebral hypoperfusion, pupil dilation and eye-roll. Large-scale Neuropixels brain recordings and machine-learning-based modelling showed that this manipulation causes the suppression of activity across a large distributed neuronal population that is not explained by changes in spontaneous behavioural movements. Additionally, bidirectional manipulation of the periventricular zone had a push-pull effect, with inhibition leading to longer syncope periods and activation inducing arousal. Finally, ablating NPY2R VSNs specifically abolished the BJR. Combined, these results demonstrate a genetically defined cardiac reflex that recapitulates characteristics of human syncope at physiological, behavioural and neural network levels.

Adult vasovagal syncope with abdominal pain diagnosed by head-up tilt combined with transcranial doppler: a preliminary study.

BACKGROUND: Syncope is a common condition that increases the risk of injury and reduces the quality of life. Abdominal pain as a precursor to vasovagal syncope (VVS) in adults is rarely reported and is often misdiagnosed.​. METHODS: We present three adult patients with VVS and presyncopal abdominal pain diagnosed by synchronous multimodal detection (transcranial Doppler [TCD] with head-up tilt [HUT]) and discuss the relevant literature. RESULTS: Case 1: A 52-year-old man presented with recurrent decreased consciousness preceded by six months of abdominal pain. Physical examinations were unremarkable. Dynamic electrocardiography, echocardiography, head and neck computed tomography angiography, magnetic resonance imaging (MRI), and video electroencephalogram showed no abnormalities. Case 2: A 57-year-old woman presented with recurrent syncope for 30 + years, accompanied by abdominal pain. Physical examination, electroencephalography, and MRI showed no abnormalities. Echocardiography showed large right-to-left shunts. Case 3: A 30-year-old woman presented with recurrent syncope for 10 + years, with abdominal pain as a precursor. Physical examination, laboratory analysis, head computed tomography, electrocardiography, and echocardiography showed no abnormalities. Syncope secondary to abdominal pain was reproduced during HUT. Further, HUT revealed vasovagal syncope, and synchronous TCD showed decreased cerebral blood flow; the final diagnosis was VVS in all cases. CONCLUSIONS: Abdominal pain may be a precursor of VVS in adults, and our findings enrich the clinical phenotypic spectrum of VVS. Prompt recognition of syncopal precursors is important to prevent incidents and assist in treatment decision-making. Abdominal pain in VVS may be a sign of sympathetic overdrive. Synchronous multimodal detection can help in diagnosing VVS and understanding hemodynamic mechanisms.

Three Simple Parameters on Admission to the Emergency Department are Predictors for Endoscopic Intervention in Patients with Suspected Nonvariceal Upper Gastrointestinal Bleeding.

BACKGROUND: A considerable number of patients with nonvariceal upper gastrointestinal bleeding (UGIB) need endoscopic intervention. OBJECTIVE: The aim of this study was to determine factors that predict the need for endoscopic intervention at the time of admission to the emergency department. METHODS: Consecutive patients with International Classification of Diseases, Tenth Revision diagnosis code K92.2 (gastrointestinal hemorrhage) who underwent upper endoscopy between February 2019 and February 2022, including patients diagnosed with nonvariceal UGIB in the emergency department in the study were reviewed retrospectively. The patients were divided into two groups: those treated endoscopically and those not treated endoscopically. These two groups were compared according to clinical and laboratory findings at admission and independent predictors for endoscopic intervention were determined using multivariate regression analysis. RESULTS: Although 123 patients (30.3%) were treated endoscopically, endoscopic treatment was not required in 283 (69.7%) patients. Syncope, mean arterial pressure (MAP), and blood urea nitrogen (BUN) at admission were independent predictors for endoscopic intervention in the multivariate analysis, after adjusting for endoscopy time. The area under the curve of the syncope+MAP+BUN combination for endoscopic intervention was 0.648 (95% CI 0.588-0.708). Although the syncope+MAP+BUN combination predicted the need for intervention significantly better than pre-endoscopy Rockall and AIMS65 scores (p = 0.010 and p < 0.001, respectively), there was no significant difference in its comparison with the Glasgow-Blatchford score (p = 0.103). CONCLUSIONS: Syncope, MAP, and BUN at admission were independent predictors for endoscopic therapy in patients with nonvariceal UGIB. Rather than using complicated scores, it would be more practical and easier to predict the need for endoscopic intervention with these three simple parameters, which are included in the Glasgow-Blatchford score.

Syncope in Athletes: A Prelude to Sudden Cardiac Death?

Athletes are generally healthy but might have certain cardiac disorders which might, during athletic participation or training, result in cardiac symptoms including syncope. Vasovagal syncope is probably the most common cause of syncope in athletes, but syncope in the context of these cardiac disorders might be a warning of sudden death.

Measuring the susceptibility to visually induced motion sickness and its relationship with vertigo, dizziness, migraine, syncope and personality traits.

The widespread use of visual technologies such as Virtual Reality increases the risk of visually induced motion sickness (VIMS). Previously, the 6-item short version of the Visually Induced Motion Sickness Susceptibility Questionnaire (VIMSSQ short form) has been validated for predicting individual variation in VIMS. The aim of the current study was to investigate how the susceptibility to VIMS is correlated with other relevant factors in the general population. A total of 440 participants (201 M, 239F), mean age 33.6 (SD 14.8) years, completed an anonymous online survey of various questionnaires including the VIMSSQ, Motion Sickness Susceptibility Questionnaire (MSSQ), Vertigo in City questionnaire (VIC), Migraine (scale), Social & Work Impact of Dizziness (SWID), Syncope (faintness), and Personality ('Big Five' TIPI). The VIMSSQ correlated positively with the MSSQ (r = 0.50), VIC (r = 0.45), Migraine (r = 0.44), SWID (r = 0.28), and Syncope (r = 0.15). The most efficient Multiple Linear Regression model for the VIMSSQ included the predictors MSSQ, Migraine, VIC, and Age and explained 40% of the variance. Factor analysis of strongest correlates with VIMSSQ revealed a single factor loading with VIMSSQ, MSSQ, VIC, Migraine, SWID, and Syncope, suggesting a common latent variable of sensitivity. The set of predictors for the VIMSSQ in the general population has similarity with those often observed in patients with vestibular disorders. Based on these correlational results, we suggest the existence of continuum of underlying risk factors for sensitivity, from healthy population to patients with extreme visual vertigo and perhaps Persistent Postural-Perceptual Dizziness.

Syncope with QT-interval prolongation and T-wave inversion in anterior and inferior leads: Foreboder of a life-threatening condition?

Even though patients with pulmonary embolism usually present with respiratory distress and tachycardia, the patient presented with syncope only. Typical ECG changes associated with PE include right axis deviation, right bundle-branch block, S1Q3T3 pattern, arrhythmia, nonspecific ST-segment changes, QR pattern in lead V1, Brugada ECG pattern, and T-wave inversions in the precordial leads. However, his electrocardiogram showed QT-interval prolongation and simultaneous T-wave inversions in the inferior and anterior leads. This ECG pattern is crucial for diagnosing PE. The patient underwent computed tomography-pulmonary angiography, which revealed pulmonary embolism. At the same time, these ECG changes should be differentiated from those of long QT syndrome, myocardial ischemia, Takotsubo cardiomyopathy, post-pacing T-wave memory, hypertrophic cardiomyopathy, and subarachnoid hemorrhage.

Sudden cardiac death related to physical exercise in the young: a nationwide cohort study of Australia.

BACKGROUND: Sudden cardiac death (SCD) during physical exercise is devastating. AIMS: To evaluate causes and circumstances of exercise-related SCD in the young in Australia. METHODS: We reviewed the National Coronial Information System database for deaths in Australia relating to cardiovascular disease in cases aged 10-35 years between 2000 and 2016. Cases who had undertaken physical exercise at the time of the event were included. We collected demographics, circumstances of death, type of physical exercise, bystander cardiopulmonary resuscitation (CPR) and automated external defibrillator (AED) use prior to ambulance arrival. RESULTS: Over a 17-year period, 1925 SCD cases were identified, of which 110 (6%) cases (median age 27 years (interquartile range 21-32 years); 92% male) were related to sports/physical exercise. Thirteen (12%) cases occurred in active athletes. Most common causes were coronary artery disease (CAD; 37%) and sudden arrhythmic death syndrome (SADS; 20%). Among Aboriginal and Torres Strait Islanders (n = 10), all deaths were related to CAD. Australian Rules Football (24%), running/jogging (14%) and soccer (14%) were the most frequent physical exercise activities. Prior symptoms were present in 39% (chest pain 37%, pre-syncope/syncope 26%). Most (87%) were witnessed, with bystander CPR in 70%. AED use prior to ambulance arrival was 8%. CONCLUSIONS: The present study demonstrates the high occurrence of CAD and SADS in SCD in the young related to physical exercise. Aboriginal and Torres Strait Islanders were disproportionately affected by CAD. Although events were commonly witnessed, AED was seldom used prior to ambulance arrival and highlights an important opportunity to improve outcomes in the post-arrest chain of survival.

An Underrecognized Cause of Recurrent Nocturnal Syncope with a Pacemaker: Sleep Rate Mode.

BACKGROUND: Nocturnal syncope is a common presentation in the emergency department, often related to orthostatic hypotension and subsequent loss of cerebral perfusion when patients get up from sleep to use the restroom faster than their cardiac output and vascular tone can accommodate. Poor hydration status and antihypertensive medications can increase this risk. Patients with syncope who present to the emergency department with a pacemaker are usually evaluated with a pacemaker interrogation to evaluate for runs of nonperfusing rhythms (e.g., ventricular tachycardia or fibrillation). Sleep rate mode (SRM) is a relatively new feature of modern pacemakers and is not currently recognized by emergency physicians. It was implemented to accommodate more physiologic fluctuations in heart rate during rapid eye movement sleep. There is a paucity of evidence supporting the clinical benefit of SRM and similarly no documentation of prior complications of SRM in the current literature. CASE REPORT: We report the case of a 92-year-old woman with a Medtronic Avisa pacemaker presenting with recurrent nocturnal syncope and bradycardia resulting in multiple emergency department visits. These episodes ultimately resolved by turning off SRM on her pacemaker. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: SRM is not currently flagged on interrogation report summaries provided to emergency physicians. This report highlights the importance of recognizing this mode as a potential etiology of nocturnal syncope related to chronotropic incompetence in patients with pacemakers.

SYNCOPE: A RARE PRESENTATION OF LYME DISEASE.

BACKGROUND: Lyme disease is one of the most common vector-borne illnesses in the United States. It is caused by Borrelia burgdorferi infection transmitted via the Ixodes tick. Rarely, it can progress to early disseminated Lyme disease with cardiac or neurologic manifestations, or both. CASE REPORT: A 41-year-old previously healthy man presented to the emergency department (ED) by ambulance after an episode of syncope. Electrocardiogram revealed right bundle branch block with borderline first-degree atrioventricular nodal block. During his admission he was noted to have night sweats and elevated procalcitonin. Infectious workup revealed positive Borrelia enzyme-linked immunosorbent assay. Further testing revealed positive Borrelia immunoglobulin M with negative immunoglobulin G, indicating a recent infection. Why should an emergency physician be aware of this? Lyme disease should be on the differential for patients presenting with vague, flu-like symptoms in the summer months in endemic areas. Treatment of early Lyme disease with doxycycline can prevent progression to secondary Lyme, which can present as a true cardiac or neurologic emergency.

Distinguishing Convulsive Syncope From Seizure Induced by Repetitive Transcranial Magnetic Stimulation: A Case Report.

ABSTRACT: Repetitive transcranial magnetic stimulation (rTMS) is Food and Drug Administration cleared for clinical use in treatment-resistant depression and a growing list of other disorders. The clinical uptake of rTMS has been facilitated by its relatively benign adverse-effect profile compared with other treatment modalities. Seizure is a rare but serious adverse event that has been reported with rTMS, when dosage exceeds safety guidelines or in individuals at increased risk for seizure. Fortunately, most rTMS-induced seizures are typically transient, with no adverse sequelae, but they may lead to treatment discontinuation. Seizure is not the only cause of loss of conscious and abnormal movements induced by rTMS. Convulsive syncope, a more common adverse event that involves loss of consciousness associated with myoclonic movements, can be difficult to differentiate from an rTMS-induced seizure. We report the case of a 52-year-old man with no known seizure risk factors, enrolled in an institutional review board-approved research study who developed what appeared to be a convulsive syncopal episode lasting 10 to 15 seconds during day 2 of a 30-day rTMS protocol (10 Hz, 120% of motor threshold, 4-second pulse train, 26-second intertrain interval, 3000 pulses per session), with no adverse sequelae. The patient's history, screening, physical examination, pertinent laboratory, neurology consult, electroencephalogram, and imaging findings are discussed. This case demonstrates that distinguishing between convulsive syncope and rTMS-induced seizure can be a diagnostic challenge. Clinicians and researchers delivering rTMS should be familiar with the risk factors for rTMS-induced seizures and rTMS-induced convulsive syncope, to screen for predisposing factors and to manage these rare adverse events if they occur.

[Diagnosis of Epilepsy: Clinical Definition, Seizure Semiology, and Differentiation from Acute Symptomatic Seizure(Provoked Seizure)].

Recently, a practical clinical definition has been proposed by the International League Against Epilepsy(ILAE). Management of an unprovoked first seizure in adults has also been reported with risk factors of recurrence relevant to epilepsy diagnosis by the American Academy of Neurology. The term "unprovoked" implies the absence of a temporary or reversible factor lowering the threshold and producing a seizure at that point in time. A seizure immediately after a stroke or head injury would exemplify a provoked seizure, as called acute symptomatic(or early)seizure, that would not lead to a diagnosis of epilepsy. The underlying mechanisms that cause the early seizure are considered to be different from those of epileptogenesis associated with recurrent epileptic seizures. Psychogenic non-epileptic seizure(PNES)or syncope resembles epileptic seizures and are often misdiagnosed. Some clinical features can help distinguish PNES or syncope from epileptic seizure. Clinicians should be familiarized with seizure semiology presumable to epilepsy. The incidence of epilepsy increases steadily after 50 years of age. As in younger people, the diagnosis of epilepsy is a clinical decision; however, in older people this can be more challenging. Many disorders, common in older people may confuse epilepsy seizures which should be differentiated by appropriate investigations.

[A man in his fifties with near-syncope episodes and persistent dizziness]. / En mann i 50-årene med nærbesvimelser og vedvarende svimmelhet.

BACKGROUND: A previously healthy male patient in his fifties presented with subacute onset of severe, diffuse dysautonomia with orthostatic hypotension as the main symptom. A lengthy interdisciplinary workup revealed a rare condition. CASE PRESENTATION: Over the course of a year, the patient was twice admitted to the local department of internal medicine because of severe hypotension. Testing showed severe orthostatic hypotension with normal cardiac function tests and no apparent underlying cause. On referral to neurological examination, symptoms of a broader autonomic dysfunction were discovered, with symptoms of xerostomia, irregular bowel habits, anhidrosis and erectile dysfunction. The neurological examination was normal, except for bilateral mydriatic pupils. The patient was tested for ganglionic acetylcholine receptor (gAChR) antibodies. A strong positive result confirmed the diagnosis of autoimmune autonomic ganglionopathy. There were no signs of underlying malignancy. The patient received induction treatment with intravenous immunoglobulin and later maintenance treatment with rituximab, resulting in significant clinical improvement. INTERPRETATION: Autoimmune autonomic ganglionopathy is a rare but likely underdiagnosed condition, which may cause limited or widespread autonomic failure. Approximately half of the patients have ganglionic acetylcholine receptor antibodies in serum. It is important to diagnose the condition as it can cause high morbidity and mortality, but responds to immunotherapy.

Major bleeding in patients with pulmonary embolism presenting with syncope.

INTRODUCTION: Syncope has been shown to be a risk factor of bleeding in patients receiving thrombolytic therapy for acute pulmonary embolism (PE). Whether syncope predicts bleeding in a broader population of patients with PE remains unknown. METHODS: We used the RIETE registry data to assess whether initial presentation with syncope could predict bleeding in PE patients receiving anticoagulant therapy, and to explore the association between presence of syncope and timing and site of major bleeding events. RESULTS: Among 45,765 patients with acute PE from March 2001 to January 2021, 6760 (14.8%) had syncope. Patients with syncope were older and more likely to have hypotension, tachycardia, hypoxaemia or elevated troponin levels than those without syncope. They also were more likely to receive thrombolytics. During the first 90 days, 1097 patients (2.4%) suffered major bleeding (gastrointestinal 335, hematoma 271 and intracranial 163) and 3611 died (158 had fatal bleeding). Patients with syncope had a higher rate of major bleeding (odds ratio [OR]: 1.63; 95% CI: 1.41-1.89) and a nonsignificantly higher rate of fatal bleeding (OR: 1.47; 95% CI: 0.99-2.17) than those without syncope. Multivariable analysis confirmed that patients with syncope were at increased risk for major bleeding (adjusted hazard ratio [aHR]: 1.34; 95% CI: 1.15-1.55). On sensitivity analysis, the increased risk for major bleeding was confirmed in patients initially receiving anticoagulant therapy without thrombolytics at 7 days (aHR: 1.47; 95% CI: 1.13-1.91) and 90 days (aHR: 1.33; 95%CI: 1.13-1.56). DISCUSSION: Syncope is a predictor of major bleeding events in patients with PE, even among those receiving anticoagulation monotherapy.

Development of a Novel Emergency Department Quality Measure to Reduce Very Low-Risk Syncope Hospitalizations.

STUDY OBJECTIVE: Emergency department (ED) evaluations for syncope are common, representing 1.3 million annual US visits and $2 billion in related hospitalizations. Despite evidence supporting risk stratification and outpatient management, variation in syncope hospitalization rates persist. We sought to develop a new quality measure for very low-risk adult ED patients with syncope that could be applied to administrative data. METHODS: We developed this quality measure in 2 phases. First, we used an existing prospective, observational ED patient data set to identify a very low-risk cohort with unexplained syncope using 2 variables: age less than 50 years and no history of heart disease. We then applied this to the 2019 Nationwide Emergency Department Sample (NEDS) to assess its potential effect, assessing for hospital-level factors associated with hospitalization variation. RESULTS: Of the 8,647 adult patients in the prospective cohort, 3,292 (38%) patients fulfilled these 2 criteria: age less than 50 years and no history of heart disease. Of these, 15 (0.46%) suffered serious adverse events within 30 days. In the NEDS, there were an estimated 566,031 patients meeting these 2 criteria, of whom 15,507 (2.7%; 95% confidence interval [CI] 2.48% to 3.00%) were hospitalized. We found substantial variation in the hospitalization rates for this very low-risk cohort, with a median rate of 1.7% (range 0% to 100%; interquartile range 0% to 3.9%). Factors associated with increased hospitalization rates included a yearly ED volume of more than 80,000 (odds ratio [OR] 3.14; 95% CI 2.02 to 4.89) and metropolitan teaching status (OR 1.5; 95% CI 1.24 to 1.81). CONCLUSION: In summary, our novel syncope quality measure can assess variation in low-value hospitalizations for unexplained syncope. The application of this measure could improve the value of syncope care.

Fragmented QRS as a risk marker for the occurrence of ventricular fibrillation in patients with variant angina.

BACKGROUND: Variant angina (VA) is caused by reversible coronary artery spasm, which is characterized by chest pain with ST-segment elevations on standard 12-lead electrocardiogram (ECG) at rest. Ventricular fibrillation (VF) is often caused by VA attack, but the risk stratification is not well understood. The purpose of this study was to evaluate the impact of fragmented QRS (fQRS) on VF occurrence in VA patients. METHODS: Ninety-four patients who showed ST elevation on 12-lead ECGs with total or nearly total occlusion in response to coronary spasm provocation test were enrolled. Among them, 16 patients had documented VF before hospital admission (n = 12) or experienced VF during provocation test (n = 4) (VF occurrence group). The fQRS was defined as the presence of spikes within the QRS complex of two or more consecutive leads. RESULTS: The prevalence of fQRS was more often observed in the VF occurrence group than in the non-VF occurrence group (63% [10/16] vs. 27% [21/78], p = 0.009). Univariate analyses revealed that age, history of syncope, QTc, and the presence of fQRS were associated with VF occurrence (p = 0.004, 0.005, 0.029, and 0.008, respectively). Furthermore, upon multivariate analyses using those risk factors, age, QTc, and fQRS predicted VF occurrence independently (p = 0.007, 0.041, and 0.014, respectively). CONCLUSIONS: The present study demonstrated that fQRS in VA patients is a risk factor for VF. The fQRS may be a useful factor for the risk stratification of VF occurrence in VA patients.

Misdiagnosis of aortic dissection: A systematic review of the literature.

BACKGROUND: Aortic dissection is a rare but potentially catastrophic condition. Misdiagnosis of aortic dissection is not uncommon as symptoms can overlap with other diagnoses. OBJECTIVE: We conducted a systematic review to better understand the factors contributing to incorrect diagnosis of this condition. METHODS: We searched MEDLINE and EMBASE for studies that evaluated the misdiagnosis of aortic dissection. The rate of misdiagnosis was pooled and results were narratively synthesized. RESULTS: A total of 12 studies with were included with 1663 patients. The overall rate of misdiagnosis of aortic dissection was 33.8%. The proportion of patients presenting with chest pain, back pain and syncope were 67.5%, 24.8% and 6.8% respectively. The proportion of patients with pre-existing hypertension was 55.4%, 30.5% were smokers while the proportion of patients with coronary artery disease, previous cardiovascular surgery or surgical trauma and Marfan syndrome was 14.7%, 5.8%, and 3.7%, respectively. Factors related to misdiagnosis included the presence of symptoms and features associated with other diseases (such as acute coronary syndrome, stroke and pulmonary embolism), the absence of typical features (such as widened mediastinum on chest X-ray) or concurrent conditions such congestive heart failure. Factors associated with more accurate diagnosis included more comprehensive history taking and increased use of imaging. CONCLUSIONS: Misdiagnosis in patients with an eventual diagnosis of aortic dissection affects 1 in 3 patients. Clinicians should consider aortic dissection as differential diagnosis in patients with chest pain, back pain and syncope. Imaging should be used early to make the diagnosis when aortic dissection is suspected.

A comprehensive group-based cognitive behavioural treatment for blood-injection-injury phobia.

OBJECTIVES: A key feature of blood-injection-injury (BII) phobia is activation of disgust responses, in addition to fear. Yet, standard treatments have largely neglected addressing disgust responses. The disorder is further complicated by fainting in 75% of sufferers. Moreover, treatments have been traditionally delivered in an individual format, which may not be as efficient as group treatment. The aim of this study was to develop a group-based programme for BII phobia, with components targeting fear, disgust, and fainting, to determine feasibility and effectiveness of such an intervention. METHODS: Participants took part in an 8-session, group-based Cognitive Behavioural Therapy (CBT) programme for BII phobia (N = 40). The key outcome measure was the Multidimensional Blood/Injury Phobia Inventory, which assesses a range of phobic stimuli and responses (including fear, disgust, and fainting). RESULTS: There were significant improvements, with large effect sizes, across symptoms over the course of treatment. Participants with higher disgust sensitivity reported higher pre-treatment symptom severity and greater life interference than those with lower disgust scores. Despite this, neither pre-treatment disgust sensitivity nor fainting history impacted on treatment response. For the first time, however, we showed that greater reductions in disgust to BII stimuli were associated with greater overall symptom reductions, highlighting the importance of disgust in the treatment of this disorder, and potentially others. CONCLUSION: Despite the heterogeneous nature of BII phobia, this group-based, modified CBT intervention was effective in reducing a variety of phobic responses, including fear, disgust, and fainting. PRACTITIONER POINTS: Disgust is a key maintaining factor in blood-injection-injury phobia, which clinicians should consider in their assessment and treatment of this disorder. There is little in the existing literature to guide clinicians in this regard. This study examined a novel group treatment for blood-injection-injury phobia which included strategies to target disgust, in addition to traditional CBT strategies to address fear and fainting. The treatment was feasible and acceptable. Symptoms of fear, disgust, and fainting reduced significantly over treatment. Changes in disgust symptoms were associated with overall symptom changes, however a control group is needed to determine the effects of individual treatment components and to make more robust conclusions about the benefits of this enhanced approach.

SCN5A Variants as Genetic Arrhythmias Triggers for Familial Bileaflet Mitral Valve Prolapse.

Mitral valve prolapse (MVP) is a common valvular heart defect with variable outcomes. Several studies reported MVP as an underestimated cause of life-threatening arrhythmias and sudden cardiac death (SCD), mostly in young adult women. Herein, we report a clinical and genetic investigation of a family with bileaflet MVP and a history of syncopes and resuscitated sudden cardiac death. Using family based whole exome sequencing, we identified two missense variants in the SCN5A gene. A rare variant SCN5A:p.Ala572Asp and the well-known functional SCN5A:p.His558Arg polymorphism. Both variants are shared between the mother and her daughter with a history of resuscitated SCD and syncopes, respectively. The second daughter with prodromal MVP as well as her healthy father and sister carried only the SCN5A:p.His558Arg polymorphism. Our study is highly suggestive of the contribution of SCN5A mutations as the potential genetic cause of the electric instability leading to ventricular arrhythmias in familial MVP cases with syncope and/or SCD history.

[Analysis of the relationship between syncope and poor prognosis in patients with acute pulmonary embolism and related factors].

Objective: To explore the association between syncope and poor prognosis and related factors of syncope in patients with acute pulmonary embolism (APE). Methods: A total of 740 patients with first diagnosed APE treated in West China Hospital of Sichuan University from September 1, 2016 to December 30, 2019 were enrolled. The basic information and clinical information (including clinical manifestations, complications, auxiliary examination, treatment and prognosis, etc.) of the patients were obtained from inpatient medical records. The patients were divided into the syncope group and the non-syncope group according to whether they had syncope or not. The basic and clinical conditions of the two groups were compared, and the factors related to syncope in APE patients were analyzed by multiple logistic regression model. Results: The proportion of APE patients with syncope was 12.6% (93/740). Age was (59±16) years in the syncope group (93 cases) and (59±17) years in the non-syncope group (647 cases), with 57.0% (53/93) and 60.4% (391/647) males, respectively. The body mass index, in-hospital mortality, proportions with high risk APE and mechanical ventilation of the syncope group were higher than those of the non-syncope group [(24.5±4.0) kg/m2 vs (23.3±3.8) kg/m2, 16.1% vs 7.7%, 4.4% vs 1.3% and 9.7% vs 2.5%, respectively]. The length of hospital stay [M (Q1, Q3)] of the syncope group was longer than that of the non-syncope group [15 (10, 22) d vs 14 (9, 22) d], and the proportions with chest pain and hemoptysis were lower than those of the non-syncope group (19.4% vs 36.8% and 14.0% vs 27.2%, respectively) (all P values<0.05). Multivariate logistic regression analysis showed that enlargement of the right heart [OR (95%CI): 2.46 (1.07, 5.64)] was a factor associated with syncope in APE patients. Conclusion: The proportion of APE patients with syncope is relatively high and is associated with poor prognosis, while enlargement of the right heart is associated with syncope in APE patients.

Usefulness of an Implantable Loop Recorder in Diagnosing Unexplained Syncope and Predictors for Pacemaker Implantation.

BACKGROUND: An implantable loop recorder (ILR) is an effective tool for diagnosing unexplained syncope (US). We examined the diagnostic utility of an ILR in detecting arrhythmic causes of US and determining which clinical factors are associated with pacemaker (PM) implantation. METHODS: This retrospective, multicenter, observational study was conducted from February 2006 to April 2018 at 11 hospitals in Korea. Eligible patients with recurrent US received an ILR to diagnose recurrent syncope and document arrhythmia. RESULTS: A total of 173 US patients (mean age, 67.6 ± 16.5 years; 107 men [61.8%]) who received an ILR after a negative conventional workup were enrolled. During a mean follow-up of 9.4 ± 11.1 months, 52 patients (30.1%) had recurrent syncope, and syncope-correlated arrhythmia was confirmed in 34 patients (19.7%). The ILR analysis showed sinus node dysfunction in 24 patients (70.6%), supraventricular tachyarrhythmia in 4 (11.8%), ventricular arrhythmia in 4 (11.8%), and sudden atrioventricular block in 2 (5.9%). Overall, ILR detected significant arrhythmia in 99 patients (57.2%) irrespective of syncope. Among patients with clinically relevant arrhythmia detected by ILR, PM implantation was performed in 60 (34.7%), an intra-cardiac defibrillator in 5 (2.9%), and catheter ablation in 4 (2.3%). In a Cox regression analysis, history of paroxysmal atrial fibrillation (PAF) (hazard ratio [HR], 2.34; 95% confidence interval [CI], 1.33-4.12; P < 0.01) and any bundle branch block (BBB) (HR, 2.52; 95% CI, 1.09-5.85; P = 0.03) were significantly associated with PM implantation. CONCLUSION: ILR is useful for detecting syncope-correlated arrhythmia in patients with US. The risk of PM is high in US patients with a history of PAF and any BBB.