Historical criteria that distinguish syncope from seizures

Seizure or syncope: Is the history-based scale feasible to use in an emergency department setting?

BACKGROUND

This study aimed to assess the efficacy of a screening questionnaire, based on historical criteria, in distinguishing between seizures and syncope in patients experiencing their first episode of transient loss of consciousness (TLOC) in a neurology emergency department.

METHODS

A prospective cohort of 159 patients with initial TLOC episodes underwent clinical observation and answered a nine-question screening questionnaire. The questionnaire's predictive ability was compared to final diagnoses determined through detailed neurology, electrophysiology, and cardiology assessments during a minimum 12-month follow-up. Logistic regression (LR) analysis was performed with final diagnosis as the outcome variable. The calibration and discrimination of the models were assessed.

RESULTS

revealed that the screening score accurately classified 72.33% of patients. Among those with positive screening scores, 65 (67.71%) had seizures compared to 31 (32.29%) with syncope. Introducing a novel risk-scoring model incorporating age and gender, in addition to the screening score, significantly improved performance achieving an accurate classification rate of 81.48%. Among patients with a positive prediction, 63 (80.77%) had seizure, whereas 15 (19.23%) had syncope.

CONCLUSIONS

Employing a structured questionnaire based on common historical criteria is a valuable tool for distinguishing between seizure and syncope in the dynamic setting of the emergency department.

Machine Learning and Artificial Intelligence Applications to Epilepsy: a Review for the Practicing Epileptologist

PURPOSE OF REVIEW

Machine Learning (ML) and Artificial Intelligence (AI) are data-driven techniques to translate raw data into applicable and interpretable insights that can assist in clinical decision making. Some of these tools have extremely promising initial results, earning both great excitement and creating hype. This non-technical article reviews recent developments in ML/AI in epilepsy to assist the current practicing epileptologist in understanding both the benefits and limitations of integrating ML/AI tools into their clinical practice.

RECENT FINDINGS

ML/AI tools have been developed to assist clinicians in almost every clinical decision including (1) predicting future epilepsy in people at risk, (2) detecting and monitoring for seizures, (3) differentiating epilepsy from mimics, (4) using data to improve neuroanatomic localization and lateralization, and (5) tracking and predicting response to medical and surgical treatments. We also discuss practical, ethical, and equity considerations in the development and application of ML/AI tools including chatbots based on Large Language Models (e.g., ChatGPT). ML/AI tools will change how clinical medicine is practiced, but, with rare exceptions, the transferability to other centers, effectiveness, and safety of these approaches have not yet been established rigorously. In the future, ML/AI will not replace epileptologists, but epileptologists with ML/AI will replace epileptologists without ML/AI.

Brain MRI and EEG overemployment in patients with vasovagal syncope: results from a tertiary syncope unit

BACKGROUND

The diagnosis of vasovagal syncope (VVS) is mainly based on history-taking and physical examination. However, brain Magnetic Resonance Imaging (MRI) and Electroencephalogram (EEG) are commonly used in the diagnostic course of VVS, despite not being indicated in the guidelines. This study aims to find the possible associated factors with the administration of brain MRI and EEG in patients with VVS.

METHODS

Patients with a diagnosis of VVS from 2017 to 2022 were included. Several demographic and syncope features were recorded. The association of these was assessed with undergoing MRI, EEG, and either MRI or EEG. Univariate and multivariable logistic regression models were also used to calculate odds ratios (OR) and 95% confidence intervals (CI).

RESULTS

A total of 1882 patients with VVS were analyzed, among which 810 underwent MRI (43.04%), 985 underwent EEG (52.34%), and 1166 underwent MRI or EEG (61.96%). Head trauma (OR 1.38, 95% CI 1.06 to 1.80), previous neurologist visit (OR 6.28, 95% CI 4.24 to 9.64), and gaze disturbance during syncope (OR 1.75, 95% CI 1.13 to 2.78) were all positively associated to the performance of brain MRI/EEG. Similar results were found for urinary incontinence (OR 2.415, 95% CI 1.494 to 4.055), amnesia (OR 1.421, 95% CI 1.053 to 1.930), headache after syncope (OR 1.321, 95% CI 1.046 to 1.672), and tonic-clonic movements in head-up tilt table test (OR 1.501, 95% CI 1.087 to 2.093). However, male sex (OR 0.655, 95% CI 0.535 to 0.800) and chest pain before syncope (OR 0.628, 95% CI 0.459 to 0.860) had significant negative associations with performing brain MRI/EEG.

CONCLUSION

Based on our findings, performing MRI or EEG was common among VVS patients while it is not indicated in the majority of cases. This should be taken into consideration to prevent inappropriate MRI/EEG when there is a typical history compatible with VVS.

Using Verbally-Reported and Video-Observed Semiology to Identify Functional Seizures

Diagnosis of functional seizures, also known as psychogenic nonepileptic seizures, starts with a clinical interview and description of the seizures. A targeted approach to this evaluation can provide valuable information to gauge the likelihood of functional seizures as compared with other similar conditions including but not limited to epileptic seizures. This review focuses on the use of patient and witness descriptions and seizure videos to identify patients with probable functional seizures. Particular emphasis is given to recognizing the limitations of the available data and the influence of health-care provider expertise on diagnostic accuracy.

Syncope and loss of consciousness after implantation of a cardioverter-defibrillator in patients with Brugada syndrome: Prevalence and characteristics in long-term follow-up

Background

Syncope is a significant prognostic factor in patients with Brugada syndrome (BrS). However, the risk of ventricular arrhythmia in patients with nonarrhythmic loss of consciousness (LOC) is similar to that in asymptomatic patients. LOC events after implantable cardioverter-defibrillator (ICD) implantation may provide insights into underlying causes of the initial LOC episode.

Objective

The purpose of this study was to examine LOC characteristics following ICD implantation.

Methods

We retrospectively analyzed 112 patients with BrS (mean age 47 years; 111 men) who were treated with an ICD. The patients were classified into 3 groups based on symptoms at implantation: asymptomatic (35 patients); LOC (46 patients); and ventricular tachyarrhythmia (VTA) (31 patients). We evaluated the incidence and cause of LOC during long-term follow-up after ICD implantation.

Results

During mean follow-up of 12.2 years, 41 patients (37%) experienced LOC after ICD implantation. Arrhythmic LOC occurred in 5 asymptomatic patients, 14 LOC patients, and 16 patients with VTA. Nonarrhythmic LOC, similar to the initial episode, occurred after ICD implantation in 6 patients with prior LOC (2 with neurally mediated syncope and 4 with epilepsy). Most epileptic patients experienced LOC during rest or sleeping, and did not show an abnormal encephalogram during initial evaluation of the LOC episodes.

Conclusion

After ICD implantation, 13% of patients had nonarrhythmic LOC similar to the initial episode. Accurate classification of LOC based on a detailed medical history is important for risk stratification, although distinguishing arrhythmic LOC from epilepsy-related LOC episodes can be challenging depending on the circumstances and characteristics of the LOC event.

Calgary score and modified calgary score in the differential diagnosis between syncope and genetic generalized epilepsy in children

The purpose of the study is to explore the use of Calgary scoring (CS) and Modified Calgary scoring (MCS) in the differentiation of genetic generalized epilepsy and syncope in children. The study involved 117 patients aged < 18 years who presented to our hospital's pediatric neurology outpatient clinic with TLOC between June 2020 and June 2022. In addition to CS and MCS scoring, all patients were subjected to statistical analysis based on their age, sex, number of episodes and distribution during the day, duration of syncope, and family history. Seventy-one patients with syncope and 46 with epilepsy were included in the study. At a CS value >  - 1, sensitivity was 86.9% and specificity 63.4%, while at an MCS value >  - 1, sensitivity was 76.1% and specificity 71.8%. CS had less specificity and sensitivity in predicting epilepsy when focal epilepsies were excluded. Abnormal behavior noted by bystanders, including witnessed unresponsive, unusual posturing, or limb jerking? (Q5) emerged as the most important question for the detection of epilepsy. Compared with other syncope findings, loss of consciousness during prolonged sitting or standing (Q9) emerged as the most important for the detection of syncope.

Impact of Admission of Patients With Syncope in Non-Teaching Hospitals Versus Teaching Hospitals: A Nationwide Analysis

Syncope is a common condition affecting many individuals, and it remains uncertain whether admission to academic medical centers (AMCs) leads to better outcomes than non-AMCs. This study is aimed to investigate whether there is a difference in mortality, length of stay (LoS), and total hospital charges between patients admitted with syncope to AMCs and non-AMCs. This retrospective cohort study used the National Inpatient Database (NIS) to examine patients aged 18 years and older admitted with a primary diagnosis of syncope to AMCs and non-AMCs from 2016 to 2020. Univariate and multivariate logistic regression analyses were conducted, adjusting for confounders, to assess the primary outcome of all-cause in-hospital mortality and secondary outcomes, including hospital LoS and total cost of admission. Patient characteristics were also described. Of the 451,820 patients who met the inclusion criteria, 69.6% were admitted to AMCs and 30.4% to non-AMCs. Patient age was similar between the two groups (68 years in AMC versus 70 years in non-AMC; p < 0.001), as was sex distribution (52% female in AMC versus 53% in non-AMC; 48% male in AMC versus 47% in non-AMC; p < 0.002). Most patients in both groups were white, while the percentages of black and Hispanic patients were slightly higher in non-AMCs. The study found no difference in all-cause mortality between patients admitted to AMCs and non-AMCs (p = 0.33). However, LoS was marginally longer in AMC patients (2.6 days in AMC versus 2.4 days in the non-AMC group; p < 0.001), and the total cost was higher for AMCs by $3,526 per admission. The estimated total economic burden related to syncope was over 3 billion USD per year. This study suggests that the teaching status of hospitals did not significantly affect the mortality of patients admitted with syncope. However, it may have contributed to marginally longer hospital LoS and higher total hospital charges.

Differentiating between epileptic and functional/dissociative seizures using semantic content analysis of transcripts of routine clinic consultations

The common causes of Transient Loss of Consciousness (TLOC) are syncope, epilepsy, and functional/dissociative seizures (FDS). Simple, questionnaire-based decision-making tools for non-specialists who may have to deal with TLOC (such as clinicians working in primary or emergency care) reliably differentiate between patients who have experienced syncope and those who have had one or more seizures but are more limited in their ability to differentiate between epileptic seizures and FDS. Previous conversation analysis research has demonstrated that qualitative expert analysis of how people talk to clinicians about their seizures can help distinguish between these two TLOC causes. This paper investigates whether automated language analysis - using semantic categories measured by the Linguistic Inquiry and Word Count (LIWC) toolkit - can contribute to the distinction between epilepsy and FDS. Using patient-only talk manually transcribed from recordings of 58 routine doctor-patient clinic interactions, we compared the word frequencies for 21 semantic categories and explored the predictive performance of these categories using 5 different machine learning algorithms. Machine learning algorithms trained using the chosen semantic categories and leave-one-out cross-validation were able to predict the diagnosis with an accuracy of up to 81%. The results of this proof of principle study suggest that the analysis of semantic variables in seizure descriptions could improve clinical decision tools for patients presenting with TLOC.

Arrhythmic syncope: From diagnosis to management

Syncope is a concerning symptom that affects a large proportion of patients. It can be related to a heterogeneous group of pathologies ranging from trivial causes to diseases with a high risk of sudden death. However, benign causes are the most frequent, and identifying high-risk patients with potentially severe etiologies is crucial to establish an accurate diagnosis, initiate effective therapy, and alter the prognosis. The term cardiac syncope refers to those episodes where the cause of the cerebral hypoperfusion is directly related to a cardiac disorder, while arrhythmic syncope is cardiac syncope specifically due to rhythm disorders. Indeed, arrhythmias are the most common cause of cardiac syncope. Both bradyarrhythmia and tachyarrhythmia can cause a sudden decrease in cardiac output and produce syncope. In this review, we summarized the main guidelines in the management of patients with syncope of presumed arrhythmic origin. Therefore, we presented a thorough approach to syncope work-up through different tests depending on the clinical characteristics of the patients, risk stratification, and the management of syncope in different scenarios such as structural heart disease and channelopathies.

Knowledge and Awareness of Syncope Among General Populations of Makkah Region in Saudi Arabia: A Cross-Sectional Study

Background Syncope is a transient loss of consciousness and postural tone due to global cerebral hypoperfusion which is followed by spontaneous recovery. It is relatively common and increases the risk of subsequent falls and injury. There is scant literature and targeted research on the population's knowledge of syncope. Hence, this study aimed to assess awareness and evaluate the knowledge of syncope among the population of the Makkah region. Methodology An online cross-sectional study was done on 563 participants. A questionnaire was used to collect data about participants' demographics, experiencing syncope in relatives, and knowledge about syncope using case scenarios. Results Females represented 72.6% of the participants and about one third of participants admitted that they had experienced syncope throughout their life. About one-third of participants admitted that they had experienced syncope throughout their life. Most of the study participants (68.9%) showed a good level of knowledge about syncope while 31.1% of them had poor knowledge; the average awareness score was 5.3±1.64. Cardiogenic syncope was the most commonly recognized type of syncope. Furthermore, participants aged between 18 and 35 years and widowed participants demonstrated a good amount of knowledge about syncopal attacks (p<0.001). Conclusions General population of the Makkah region in Saudi Arabia had a sufficient level of knowledge about syncope. Additional studies along with educational programs are needed.

Epilepsy diagnosis using a clinical decision tool and artificially intelligent electroencephalography

OBJECTIVE

To construct a tool for non-experts to calculate the probability of epilepsy based on easily obtained clinical information combined with an artificial intelligence readout of the electroencephalogram (AI-EEG).

MATERIALS AND METHODS

We performed a chart review of 205 consecutive patients aged 18 years or older who underwent routine EEG. We created a point system to calculate the pre-EEG probability of epilepsy in a pilot study cohort. We also computed a post-test probability based on AI-EEG results.

RESULTS

One hundred and four (50.7%) patients were female, the mean age was 46 years, and 110 (53.7%) were diagnosed with epilepsy. Findings favoring epilepsy included developmental delay (12.6% vs 1.1%), prior neurological injury (51.4% vs 30.9%), childhood febrile seizures (4.6% vs 0.0%), postictal confusion (43.6% vs 20.0%), and witnessed convulsions (63.6% vs 21.1%); findings favoring alternative diagnoses were lightheadedness (3.6% vs 15.8%) or onset after prolonged sitting or standing (0.9% vs 7.4%). The final point system included 6 predictors: Presyncope (-3 points), cardiac history (-1), convulsion or forced head turn (+3), neurological disease history (+2), multiple prior spells (+1), postictal confusion (+2). Total scores of ≤1 point predicted <5% probability of epilepsy, while cumulative scores ≥7 predicted >95%. The model showed excellent discrimination (AUROC: 0.86). A positive AI-EEG substantially increases the probability of epilepsy. The impact is greatest when the pre-EEG probability is near 30%.

SIGNIFICANCE

A decision tool using a small number of historical clinical features accurately predicts the probability of epilepsy. In indeterminate cases, AI-assisted EEG helps resolve uncertainty. This tool holds promise for use by healthcare workers without specialty epilepsy training if validated in an independent cohort.

Pediatric syncope: pearls and pitfalls in history taking

Syncope is a heterogeneous syndrome with complex underlying mechanisms, hence, the spectrum of patients presenting with syncope is broad. The diagnosis of syncope begins with history taking, and an accurate diagnosis can be established through correct history taking and interpretation. Building and interpreting patient history are the main factors that cause a diagnostic yield gap between experts and nonexperts. The most frequent source of error is a clinician's misconception rather than an inaccurate account of patient symptoms. Clinicians can have several diagnostic pitfalls while evaluating patient history, which can be avoided by in-depth understanding of the link between syncope pathophysiology and clinical clues. Furthermore, clinicians need to understand the clinical features of diseases that require differentiation from syncope, such as seizures. The use of confusing terms is one of the barriers that prevents accurate diagnosis and communication between doctors and patients. In this review, we address the terms of syncope and its essential history-taking components in connection with the mechanism of syncope.

Clinical and Instrumental Characterization of Patients With Late-Onset Epilepsy

Epilepsy is classically considered a childhood disease. However, it represents the third most frequent neurological condition in the elderly, following stroke, and dementia. With the progressive aging of the general population, the number of patients with Late-Onset Epilepsy (LOE) is constantly growing, with important economic and social consequences, in particular for the more developed countries where the percentage of elderly people is higher. The most common causes of LOE are structural, mainly secondary to cerebrovascular or infectious diseases, brain tumors, trauma, and metabolic or toxic conditions. Moreover, there is a growing body of evidence linking LOE with neurodegenerative diseases, particularly Alzheimer's disease (AD). However, despite a thorough characterization, the causes of LOE remain unknown in a considerable portion of patients, thus termed as Late-Onset Epilepsy of Unknown origin (LOEU). In order to identify the possible causes of the disease, with an important impact in terms of treatment and prognosis, LOE patients should always undergo an exhaustive phenotypic characterization. In this work, we provide a detailed review of the main clinical and instrumental techniques for the adequate characterization of LOE patients in the clinical practice. This work aims to provide an easy and effective tool that supports routine activity of the clinicians facing LOE.

Psychogenic Pseudosyncope: Real or Imaginary? Results from a Case-Control Study in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) Patients

Background and objectives: Orthostatic intolerance (OI) is a clinical condition in which symptoms worsen upon assuming and maintaining upright posture and are ameliorated by recumbency. OI has a high prevalence in patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Exact numbers on syncopal spells especially if they are on a weekly or even daily basis are not described. Although not a frequent phenomenon, this symptomatology is of very high burden to the patient if present. To explore whether patients with very frequent (pre)syncope spells diagnosed elsewhere with conversion or psychogenic pseudosyncope (PPS) might have another explanation of their fainting spells than behavioral psychiatric disorders, we performed a case-control study comparing ME/CFS patients with and without PPS spells. Methods and results: We performed a case-control study in 30 ME/CFS patients diagnosed elsewhere with PPS and compared them with 30 control ME/CFS patients without syncopal spells. Cases were gender, age and ME/CFS disease duration matched. Each underwent a tilt test with extracranial Doppler measurements for cerebral blood flow (CBF). ME/CFS cases with PPS had a significant larger CBF reduction at end tilt than controls: 39 (6)% vs. 25 (4)%; (p < 0.0001). Cases had more severe disease compared with controls (chi-square p < 0.01 and had a p = 0.01) for more postural orthostatic tachycardia syndrome in cases compared with controls. P_ETCO₂ end-tilt differed also, but the magnitude of difference was smaller than compared with the CBF reduction: there were no differences in heart rate and blood pressure at either end-tilt testing period. Compared with the test with the stockings off, the mean percentage reduction in cardiac output during the test with compression stockings on was lower, 25 (5) mmHg versus 29 (4) mmHg (p < 0.005). Conclusions: This study demonstrates that in ME/CFS patients suspected of having PPS, or conversion, CBF measurements end-tilt show a large decline compared with a control group of ME/CFS patients. Therefore, hypoperfusion offers an explanation of the orthostatic intolerance and syncopal spells in these patients, where it is clear that origin might not be behavioral or psychogenic, but have a clear somatic pathophysiologic background.

Clinical utility of serum prolactin and lactate concentrations to differentiate epileptic seizures from non-epileptic attacks in the emergency room

PURPOSE

To evaluate the diagnostic utility of serum prolactin (PRL) and lactate (LAC) concentrations for patients presenting with either or both convulsions and transient loss of consciousness (TLOC) in the emergency room (ER).

METHODS

This was a retrospective single-center study conducted in a tertiary care hospital ER. Medical records of consecutive patients who presented with convulsions or TLOC between January 2018 and December 2020 were reviewed. Patients with an ER diagnosis of epileptic seizures, psychogenic non-epileptic seizure (PNES), and syncope were selected for analysis. Serum PRL and LAC concentrations were measured within 3 h of the event and compared between groups.

RESULTS

Among the 440 eligible patients, 173 (39.3%) were included for analysis. Serum PRL concentration was significantly higher in patients with epileptic seizures with convulsions than in those with PNES with convulsions (p < 0.001) and convulsive syncope (p = 0.023). Serum LAC concentration was not significantly elevated in patients with convulsive syncope. Using a PRL cut-off value of 24.0 ng/mL, serum PRL concentration had 100.0% sensitivity and 82.9% specificity for differentiating between PNES and other attacks without convulsions.

CONCLUSION

Elevated serum PRL with normal serum LAC concentration in patients who have attacks with convulsions suggests convulsive syncope. Serum PRL concentration is useful in the diagnosis of PNES with convulsions. However, serum LAC concentration is not useful as a routine screening test for attacks without convulsions in the ER.

The language of seizure identification: A qualitative investigation

OBJECTIVE

Clinical history taking is often the most important factor in seizure recognition and the diagnosis of epilepsy. Apart from subspecialist evaluation, patients frequently present for initial evaluation of seizures in emergency departments, urgent care clinics, and primary care clinics. We utilized qualitative methods to assess the current approaches and language used by both subspecialist and non-specialist physicians when interviewing adult patients with suspected seizures to create a clinical tool to aid in seizure diagnosis.

METHODS

We carried out semi- structured interviews with 10 physicians spanning a range of specialties, practice locations, and clinical experience. This included epilepsy specialists and non-specialists in fields where evaluation of new-onset seizures is common: emergency medicine, internal medicine, and family medicine. Thematic analysis was used to develop a "Seizure Identifier" questionnaire, which was subsequently reviewed by five independent experts for content and face validity.

RESULTS

Our analysis revealed that across specialties and practice settings, physicians have a structured approach in evaluating patients who present with suspected seizures. Five key characteristics important for identifying seizures emerged across interviews: sudden-onset unprovoked symptoms, short-lasting symptoms, strange or difficult-to-describe symptoms, highly stereotyped symptoms, and postictal symptoms. After independent review, these were translated into an eight-question "Seizure Identifier" tool.

SIGNIFICANCE

This study highlights important concepts for clinical practice regarding seizure identification. Using themes from our analysis, we were able to create a tool that may aid non-specialists in the approach to history taking for adult patients who present with suspected seizures and may help improve time to subspecialist evaluation. Importantly, this tool can be tested in future research for improving seizure recognition and improving timely epilepsy diagnosis.

A case of juvenile myoclonic epilepsy in which a disease‐specific question led to the diagnosis

A 17‐year‐old female patient presented to our hospital with repeated transient loss of consciousness lasting less than 10 min. After regaining consciousness, she experienced no disorientation, confusion, tongue‐biting, or incontinence. Physical findings, blood tests, electrocardiogram, and echocardiogram showed no obvious abnormalities. On being asked whether she had experienced sudden rapid body movements, she answered “yes.” Therefore, we suspected juvenile myoclonic epilepsy (JME) and obtained an electroencephalogram, which showed diffuse bilateral bursts of spike‐and‐wave complexes, confirming the diagnosis. In adolescent patients with transient loss of consciousness, myoclonic jerks should be actively confirmed for the diagnosis of JME.

Syncope, Epilepsy and Ictal Asystole: A Case Series and Narrative Review

IMPORTANCE

Syncope is a common presentation to emergency departments, and cardiac and neurological aetiologies are the predominant causes. Ictal asystole is a rare cardio-neural phenomenon seen in epilepsy syndromes whereby a seizure causes asystole (≥3 s) leading to syncope.

OBSERVATIONS

We present three cases of ictal asystole, together with a narrative review of the literature to assess the prevalence of the condition and review the pathophysiology, diagnosis and management. Our review of the literature has shown that ictal asystole is an unlikely contributor to sudden unexplained death with epilepsy (SUDEP). Pacemaker insertion may limit morbidity from trauma related to syncopal episodes but does not impact mortality.

CONCLUSIONS AND RELEVANCE

Patients with ictal asystole should be diagnosed with concurrent electroencephalogram-electrocardiograph (EEG-ECG) monitoring, have their anti-epileptic drugs optimised and be considered for epilepsy surgery if feasible. The use of longer term ECG monitoring may be used as a diagnostic aid if ictal asystole is suspected. If there are ongoing syncopal episodes with associated ictal asystole ≥6 seconds, particularly despite medical therapy, a permanent pacemaker may be considered to reduce morbidity. Current guidelines should be updated to reflect the increasing knowledge of this condition.

A Rational Evaluation of the Syncope Patient: Optimizing the Emergency Department Visit

Syncope accounts for up to 2% of emergency department visits and results in the hospitalization of 12–86% of patients. There is often a low diagnostic yield, with up to 50% of hospitalized patients being discharged with no clear diagnosis. We will outline a structured approach to the syncope patient in the emergency department, highlighting the evidence supporting the role of clinical judgement and the initial electrocardiogram (ECG) in making the preliminary diagnosis and in safely identifying the patients at low risk of short- and long-term adverse events or admitting the patient if likely to benefit from urgent intervention. Clinical decision tools and additional testing may aid in further stratifying patients and may guide disposition. While hospital admission does not seem to offer additional mortality benefit, the efficient utilization of outpatient testing may provide similar diagnostic yield, preventing unnecessary hospitalizations.

A randomized study of yoga therapy for the prevention of recurrent reflex vasovagal syncope

AIMS

Vasovagal syncope (VVS) is a common cardiovascular dysautonomic disorder that significantly impacts health and quality of life (QoL). Yoga has been shown to have a positive influence on cardiovascular autonomics. This study assessed the effectiveness of yoga therapy on the recurrence of VVS and QoL.

METHODS AND RESULTS

We randomized subjects with recurrent reflex VVS (>3 episodes in the past 1 year) and positive head-up tilt test to guideline-directed therapy (Group 1) or yoga therapy (Group 2). Patients in Group 1 were advised guideline-directed treatment and Group 2 was taught yoga by a certified instructor. The primary endpoint was VVS recurrences and QoL. Between June 2015 and February 2017, 97 highly symptomatic VVS patients were randomized (Group 1: 47 and Group 2: 50). The mean age was 33.1 ± 16.6 years, male:female of 40:57, symptom duration of 17.1 ± 20.7 months, with a mean of 6.4 ± 6.1 syncope episodes. Over a follow-up of 14.3 ± 2.1 months Group 2 had significantly lower syncope burden compared with Group 1 at 3 (0.8 ± 0.9 vs. 1.8 ± 1.4, P < 0.001), 6 (1.0 ± 1.2 vs. 3.4 ± 3.0, P < 0.001), and at 12 months (1.1 ± 0.8 vs. 3.8 ± 3.2, P < 0.001). The Syncope functional score questionnaire was significantly lower in Group 2 compared with Group 1 at 3 (31.4 ± 7.2 vs. 64.1 ± 11.5, P < 0.001), 6 (26.4 ± 6.3 vs. 61.4 ± 10.7, P < 0.001), and 12 months (22.2 ± 4.7 vs. 68.3 ± 11.4, P < 0.001).

CONCLUSION

For patients with recurrent VVS, guided yoga therapy is superior to conventional therapy in reducing symptom burden and improving QoL.

Frequency of syncope as a presenting symptom in channelopathies diagnosed in childhood. Can the multivariable EGSYS score unmask these children?

Pediatric syncope raises cardiac etiology concern as it might be the first sign of life-threatening arrhythmia syndromes. Our aim was to study the incidence of syncope as the presenting symptom in children with arrhythmia syndromes, and if known, warning signs are helpful to reveal the arrhythmic origin. All data on children with channelopathy was followed by a tertiary pediatric cardiac center between 2000 and 2018 and data were reviewed retrospectively. Forty-eight patients were enrolled, representing long QT syndrome (n = 39), catecholaminergic polymorphic ventricular tachycardia (n = 5), and Brugada syndrome (n = 4). Presenting symptoms were syncope in 13 cases [27%] (including 7 initially mislabeled as epilepsy) and sudden cardiac arrest (SCA) in 9 cases [19%]. In the rest of the group, the concern for arrhythmic etiology was raised by either an abnormal ECG during sports medicine screening (n = 13) [27%] or a positive family history of channelopathy (n = 13) [27%]. None of the patients presenting with SCA had a prior syncopal history. Six patients presenting with syncope and afterward treated with ICD had an appropriate shock. Description of witnessed syncope was available in eight out of thirteen children presenting with syncope. Multivariable EGSYS score suggested cardiac origin (≥ 3 points) in 7 out of 8 (88%) patients.Conclusions: Syncope was a relatively uncommon presenting symptom of channelopathies in this sample and did not always precede sudden cardiac arrests. However, we found that multivariable EGSYS score can identify syncope of arrhythmic origin, raising suspicion for pediatric channelopathies even in patients previously misdiagnosed with epilepsy. What is known: • Cardiac syncope is rare in children but can be the first sign of a potentially fatal primary arrhythmia syndrome and is frequently misdiagnosed as atypical/therapy-resistant epilepsy. • Multivariate EGSYS score is effective to diagnose cardiac syncope in adults. What is new: • Cardiac syncope as a presenting symptom is not common in children with cardiac channelopathies and is not often present before sudden cardiac arrest. • Multivariable EGSYS score might identify cardiac syncope in children with a hereditary and secondary channelopathy.

Investigation on the Incidence of Syncope in Children and Adolescents Aged 2-18 Years in Changsha

Objectives: Syncope is a common clinical symptom, while there are less relevant literature and targeted research on childhood morbidity. This article makes a cross-section survey on the incidence of syncope in children and adolescents aged 2-18 years in Changsha. Materials and Methods: There were 4,352 children and adolescents aged 2-18 years randomly selected from six primary and secondary schools and three kindergartens in Changsha from March 2018 to November 2018. There were 4,916 standardized questionnaires issued, and 4,352 (88.53%) valid questionnaires were recovered. Results: (1) Incidence: 17.37% of children and adolescents aged 2-18 years who had at least more than one syncope; the incidence in the adolescence (28.85%) was higher than that in the school age (8.32%) and in the preschool age (2.71%) (P < 0.01). (2) Age at onset: 13.9 ± 3.1 years old, with a peak age of 16 years. (3) Gender difference: The incidence in adolescent females was higher than that in males (31.72 vs. 26.25%, P < 0.05). In inducements, females had higher rates than males in sweltering environment (P < 0.01), whereas males had higher rates than females in urination (P < 0.05). Dizziness, nausea, sweating, and facial pallor were higher in females than in males in presyncope (P < 0.05). Conclusions: The incidence of syncope in children and adolescents aged 2-18 years in Changsha is 17.37%. The incidence of syncope is different between males and females in different age groups; there are gender differences in syncope inducements and presyncope.

Syncopal attacks in children: Is it cardiac or epilepsy related?

BACKGROUND

Transient loss of consciousness (TLOC) may be mistaken for other disorders like epilepsy. Our objectives were to identify symptoms that could help differentiate epilepsy from syncope among children with TLOC and to validate previously suggested criteria.

METHODS

We retrospectively reviewed the charts of patients aged 18 years or younger who presented with TLOC attacks from January 2008 to December 2018 at King Saud University Medical City, Riyadh, Saudi Arabia. Symptoms from which epilepsy and syncope could be predicted with high accuracy were included in the previously suggested criteria. The discriminative abilities of current and previous criteria were examined in receiver-operating characteristic analyses.

RESULTS

Data from 46 patients, 32 with confirmed epilepsy and 14 with syncope, were included in this analysis. The mean age was 12.1 years (S.D., 4.3 years), and 60.9% of the patients were girls. According to our proposed criteria, the sensitivity, specificity, and accuracy of symptoms in predicting epilepsy were 68.8%, 85.7%, and 73.9%, respectively, and the area under the curve was 0.814 (confidence interval 0.686 to 0.941, P = 0.001). According to previously suggested criteria, the sensitivity, specificity, and accuracy of symptoms in predicting epilepsy were 63.2%, 62.5%, and 63.0%, respectively, and the area under the curve was 0.730 (confidence interval 0.541 to 0.92, P = 0.063).

CONCLUSIONS

A number of self-reported/observed symptoms can be used to distinguish epilepsy from syncope with high discriminative ability. The current findings still need to be validated in larger, preferably multiple populations before they can be safely relied upon.

Prehospital lactate levels in blood as a seizure biomarker: A multi-center observational study

OBJECTIVE

The objective of this study was to assess the value of prehospital measurement of lactate level in blood for diagnosis of seizures in cases of transient loss of consciousness.

METHODS

Between March 2018 and September 2019, prehospital lactate was measured with a point-of-care device by the emergency medical services in an area serving a population of 900 000. A total of 383 cases of transient loss of consciousness were identified and categorized as tonic-clonic seizure (TCS), other seizure, syncope, or other cause, according to the final diagnosis in the electronic medical records system. Receiver operating characteristic curve analyses were used to identify the optimal lactate cut-off.

RESULTS

A total of 383 cases were included (135 TCS, 42 other seizure, 163 syncope, and 43 other causes). The median lactate level in TCS was 7.0 mmol/L, compared to a median of 2.0 mmol/L in all other cases (P < .001). The area under the curve (AUC) of TCS vs nonepileptic causes was 0.87 (95% confidence interval [CI] 0.83-0.91). The optimal cut-off (Youden index, 67.8%) was 4.75 mmol/L, with 79% sensitivity (95% CI 71-85) and 89% specificity (95% CI 85-93) for TCS.

SIGNIFICANCE

Prehospital lactate can be a valuable tool for identifying seizures in transient loss of consciousness. For acceptable specificity, a higher cut-off than that previously demonstrated for hospital-based measurements must be used when values obtained close to the time of the event are interpreted.

Children with transient loss of consciousness: Clinical characteristics and the effectiveness of diagnostic tests

BACKGROUND

Transient loss of consciousness (TLOC) is common among children and adolescents. The aims of this study were to identify clinical differences between patients with vasovagal syncope and those with epileptic seizures, which account for a large proportion of TLOC cases, and to evaluate the effectiveness of various diagnostic tests.

METHODS

The medical records of 160 children and adolescents with TLOC were analyzed retrospectively, and age, sex, clinical symptoms, and trigger factors were recorded. The cardiological and neurological evaluations performed included electrocardiograms, computed tomography scanning, magnetic resonance imaging, electroencephalograms (EEGs), echocardiograms, and head-up tilt tests (HUTTs). Overall assessments of the 160 patients generated final diagnoses.

RESULTS

The mean age of patients was 14.6 years old and TLOC occurred more frequently among girls (59.4%). The most common final diagnosis was vasovagal syncope (n = 102, 63.4%), followed by undetermined (n = 21, 13.1%) and epileptic seizures (n = 17, 10.6%). There were many other diagnoses, including cardiogenic syncope (1.3%). Patients diagnosed with vasovagal syncope were much more likely to have dizziness or light-headedness and blurred vision as pre-symptoms (p < 0.05), whereas patients diagnosed with epileptic seizures were more likely to have convulsions as an accompanying sign (p < 0.05). In addition, standing up was the most significant trigger factor for TLOC among those diagnosed with vasovagal syncope (p < 0.05). The sensitivity, specificity, and accuracy of the HUTT for vasovagal syncope were 95.1%, 75.0%, and 91.8%, respectively. Similarly, the sensitivity, specificity, and accuracy of EEGs for epileptic seizures were 80.0%, 70.6%, and 80.0%, respectively.

CONCLUSION

Vasovagal syncope and epileptic seizures should be considered as possible causes of most cases of TLOC in children and adolescents. An accurate case history and appropriate evaluation are essential for correct diagnoses.

An Elderly Woman With Recurrent Transient Loss of Consciousness Preceded by Hallucinatory Attacks

We report a patient with transient loss of consciousness preceded by hallucinations caused by cardiac syncope. The diagnosis was confirmed by simultaneous video-electrocardiogram-electroencephalogram recording of an event. The attacks no longer occurred after pacemaker implantation. Clinical features helpful in guiding decision making in transient loss of consciousness are discussed. (Level of Difficulty: Beginner.)

Screening Pediatric Patients in New-Onset Syncope (SPINS) Study

Objectives. The primary objective is to determine the frequency of history findings associated with cardiac syncope. Second, to determine the frequency of abnormal electrocardiograms (EKG) in patients presenting with typical vasovagal syncope. Methods. Retrospective chart review from January 2006 to April 2017 of children aged 5 to 18 years presenting to the emergency department with a chief complaint of syncope. Target population was all patients with first episode of syncope and a documented EKG. Excluded patients were those with head trauma, drug intoxication, current pregnancy, seizure, and any endocrine problem. Patients with cardiac causes of syncope were identified by an abnormal EKG or echocardiogram. Specific history findings (past cardiac history, chest pain, palpitations, syncope with exercise, absence of prodrome with syncope) were compared with those with and without cardiac etiology of syncope. The possibility of missing a patient with cardiac cause of syncope based on specific history findings was identified. Results. Of the total 4115 visits of patients with chief complaints of syncope, 2293 patients (55.7%) met the inclusion criteria. Nine patients (0.39%) were identified with cardiac etiology of syncope. The remaining were determined to be of vasovagal origin. All patients with cardiac etiology of syncope were found to have one positive specific history findings. A total of 1972 patients were identified with absence of specific history findings; no patient had a cardiac etiology of syncope. Conclusions. This study identifies screening questions to identify cardiac syncope. Implementing these standard questions could potentially decrease resource utilization and time for evaluation as well as guide follow-up.

Pulmonary tumor thrombotic microangiopathy presenting as recurrent syncope

Pulmonary tumor thrombotic microangiopathy is a rare condition in which embolization of tumor cells to the pulmonary arterioles causes fibrocellular intimal thickening and activation of the coagulation cascade resulting in pulmonary hypertension and right heart failure. Herein, we highlight a young 35-year-old male with no known past medical history who presented with recurrent syncope and dyspnea, and was found to have severe right heart failure and pulmonary hypertension. He developed sudden clinical deterioration and died after a cardiac arrest. Autopsy revealed poorly differentiated gastric adenocarcinoma and pulmonary tumor thrombotic microangiopathy. New onset severe pulmonary hypertension and right heart failure without any other obvious etiology should encourage the reader to evaluate for pulmonary tumor thrombotic microangiopathy and undergo a diligent search for underlying malignancy. This case highlights recurrent syncope as a rare presentation of this rapidly fatal disease.

Transcranial Magnetic Stimulation (TMS) Safety with Respect to Seizures: A Literature Review

Transcranial magnetic stimulation is an increasingly popular FDA-approved treatment for resistant depression, migraines, and OCD. Research is also underway for its use in various other psychiatric and medical disorders. Although rare, seizures are a potential adverse event of TMS treatment. In this article, we discuss TMS-related seizures with the various coils used to deliver TMS, the risk factors associated with seizures, the differential diagnosis of its presentations, the effects of sleep deprivation and alcohol use on seizures, as well as seizure risks with protocols for traditional TMS, theta-burst stimulation, and accelerated TMS. A discussion is presented comparing the potential risk of seizures with various psychotropic medications versus TMS. Included are case reports of TMS seizures in the child/adolescent patient, bipolar disorder patients, patients with a history of a traumatic brain injury, and those with epilepsy. Reports are also shared on TMS use without seizures in patients with a history of head injuries and TMS's continued use if patients have a seizure during their TMS treatment. Findings generated in this review suggest the following. Seizures, if present, are usually self-limiting. Most treatment recommendations for TMS-related seizures are supportive in nature. The risk of TMS-related seizures is <1% overall. TMS has successfully been used in patients with epilepsy, traumatic brain injuries, and those with a prior TMS-related seizure. The rate of TMS-related seizures is comparable to that of most psychotropic medications. While having a seizure is a rare but serious adverse effect of TMS, the benefits of treating refractory depression with TMS may outweigh the risk of suicidal ideation and other significant complications of depression.

Machine learning as a diagnostic decision aid for patients with transient loss of consciousness

Background

Transient loss of consciousness (TLOC) is a common reason for presentation to primary/emergency care; over 90% are because of epilepsy, syncope, or psychogenic non-epileptic seizures (PNES). Misdiagnoses are common, and there are currently no validated decision rules to aid diagnosis and management. We seek to explore the utility of machine-learning techniques to develop a short diagnostic instrument by extracting features with optimal discriminatory values from responses to detailed questionnaires about TLOC manifestations and comorbidities (86 questions to patients, 31 to TLOC witnesses).

Methods

Multi-center retrospective self- and witness-report questionnaire study in secondary care settings. Feature selection was performed by an iterative algorithm based on random forest analysis. Data were randomly divided in a 2:1 ratio into training and validation sets (163:86 for all data; 208:92 for analysis excluding witness reports).

Results

Three hundred patients with proven diagnoses (100 each: epilepsy, syncope and PNES) were recruited from epilepsy and syncope services. Two hundred forty-nine completed patient and witness questionnaires: 86 epilepsy (64 female), 84 PNES (61 female), and 79 syncope (59 female). Responses to 36 questions optimally predicted diagnoses. A classifier trained on these features classified 74/86 (86.0% [95% confidence interval 76.9%-92.6%]) of patients correctly in validation (100 [86.7%-100%] syncope, 85.7 [67.3%-96.0%] epilepsy, 75.0 [56.6%-88.5%] PNES). Excluding witness reports, 34 features provided optimal prediction (classifier accuracy of 72/92 [78.3 (68.4%-86.2%)] in validation, 83.8 [68.0%-93.8%] syncope, 81.5 [61.9%-93.7%] epilepsy, 67.9 [47.7%-84.1%] PNES).

Conclusions

A tool based on patient symptoms/comorbidities and witness reports separates well between syncope and other common causes of TLOC. It can help to differentiate epilepsy and PNES. Validated decision rules may improve diagnostic processes and reduce misdiagnosis rates.

Classification of evidence

This study provides Class III evidence that for patients with TLOC, patient and witness questionnaires discriminate between syncope, epilepsy and PNES.

Did This Patient Have Cardiac Syncope?: The Rational Clinical Examination Systematic Review

IMPORTANCE

Syncope can result from a reduction in cardiac output from serious cardiac conditions, such as arrhythmias or structural heart disease (cardiac syncope), or other causes, such as vasovagal syncope or orthostatic hypotension.

OBJECTIVE

To perform a systematic review of studies of the accuracy of the clinical examination for identifying patients with cardiac syncope.

STUDY SELECTION

Studies of adults presenting to primary care, emergency departments, or referred to specialty clinics.

DATA EXTRACTION AND SYNTHESIS

Relevant data were abstracted from articles in databases through April 9, 2019, and methodologic quality was assessed. Included studies had an independent comparison to a reference standard.

MAIN OUTCOMES AND MEASURES

Sensitivity, specificity, and likelihood ratios (LRs).

RESULTS

Eleven studies of cardiac syncope (N = 4317) were included. Age at first syncope of at least 35 years was associated with greater likelihood of cardiac syncope (n = 323; sensitivity, 91% [95% CI, 85%-97%]; specificity, 72% [95% CI, 66%-78%]; LR, 3.3 [95% CI, 2.6-4.1]), while age younger than 35 years was associated with a lower likelihood (LR, 0.13 [95% CI, 0.06-0.25]). A history of atrial fibrillation or flutter (n = 323; sensitivity, 13% [95% CI, 6%-20%]; specificity, 98% [95% CI, 96%-100%]; LR, 7.3 [95% CI, 2.4-22]), or known severe structural heart disease (n = 222; range of sensitivity, 35%-51%, range of specificity, 84%-93%; range of LR, 3.3-4.8; 2 studies) were associated with greater likelihood of cardiac syncope. Symptoms prior to syncope that were associated with lower likelihood of cardiac syncope were mood change or prodromal preoccupation with details (n = 323; sensitivity, 2% [95% CI, 0%-5%]; specificity, 76% [95% CI, 71%-81%]; LR, 0.09 [95% CI, 0.02-0.38]), feeling cold (n = 412; sensitivity, 2% [95% CI, 0%-5%]; specificity, 89% [95% CI, 85%-93%]; LR, 0.16 [95% CI, 0.06-0.64]), or headache (n = 323; sensitivity, 3% [95% CI, 0%-7%]; specificity, 80% [95% CI, 75%-85%]; LR, 0.17 [95% CI, 0.06-0.55]). Cyanosis witnessed during the episode was associated with higher likelihood of cardiac syncope (n = 323; sensitivity, 8% [95% CI, 2%-14%]; specificity, 99% [95% CI, 98%-100%]; LR, 6.2 [95% CI, 1.6-24]). Mood changes after syncope (n = 323; sensitivity, 3% [95% CI, 0%-7%]; specificity, 83% [95% CI, 78%-88%]; LR, 0.21 [95% CI, 0.06-0.65]) and inability to remember behavior prior to syncope (n = 323; sensitivity, 5% [95% CI, 0%-9%]; specificity, 82% [95% CI, 77%-87%]; LR, 0.25, [95% CI, 0.09-0.69]) were associated with lower likelihood of cardiac syncope. Two studies prospectively validated the accuracy of the multivariable Evaluation of Guidelines in Syncope Study (EGSYS) score, which is based on 6 clinical variables. An EGSYS score of less than 3 was associated with lower likelihood of cardiac syncope (n = 456; range of sensitivity, 89%-91%, range of specificity, 69%-73%; range of LR, 0.12-0.17; 2 studies). Cardiac biomarkers show promising diagnostic accuracy for cardiac syncope, but diagnostic thresholds require validation.

CONCLUSIONS AND RELEVANCE

The clinical examination, including the electrocardiogram as part of multivariable scores, can accurately identify patients with and without cardiac syncope.

The Fainting Assessment Inventory: A 10-Item Instrument Developed to Screen for Psychogenic Nonsyncopal Collapse Among Youth Referred for Syncope

The conversion disorder that appears like syncope is common but poorly recognized. The study aimed to develop and validate a brief, clinician-administered screening tool to discriminate psychogenic nonsyncopal collapse (PNSC) among young patients referred for fainting. Consecutive patients with PNSC and with syncope (15.4 ± 2.2 years) completed a 92-item inventory highlighting features typical of PNSC and neurally mediated syncope (n = 35, each cohort). Fourteen items were retained and revised and then administered to new cohorts ultimately diagnosed with PNSC or syncope (n = 40, each cohort). Further revision led to a 10-item Fainting Assessment Inventory (FAI-10). Scoring the syncope ratings positively and the PNSC ratings negatively, median scores differed between cohorts with PNSC and with syncope (-6 vs. 7; p < 0.001). Diagnostic sensitivity (0.95), specificity (0.875), positive predictive value (0.889), negative predictive value (0.93), and area under the curve (0.973) were calculated. The FAI-10 furthers clinicians' ability to distinguish various forms of transient loss of consciousness.

Seizures and Epilepsy

Epilepsy affects 65 million people worldwide, and is a leading neurologic cause of loss of quality-adjusted life years. The diagnosis of seizures and epilepsy often depends on a careful history, and is supported with electroencephalogram and imaging. First-line treatment of epilepsy includes medical management. Antiepileptic drugs must be chosen with the patient's particular comorbidities in mind. Drug-resistant epilepsy cases should be referred to an epilepsy specialist and may be evaluated for additional medications, epilepsy surgery, neurostimulation, or dietary therapy. When caring for women, providers must take into account needs for contraception or pregnancy safety where applicable.

Value of witness observations in the differential diagnosis of transient loss of consciousness

OBJECTIVE

This retrospective study explores to what extent additional information from event witnesses provided using the novel 31-item Paroxysmal Event Observer (PEO) Questionnaire improves the differentiation among epilepsy, syncope, and psychogenic nonepileptic seizures (PNES) achievable with information provided by patients alone.

METHODS

Patients with transient loss of consciousness caused by proven epilepsy (n = 86), syncope (n = 79), or PNES (n = 84) attending specialist neurology/syncope services in the United Kingdom and event observers provided Paroxysmal Event Profile (PEP), PEO, and personal information (PI) (e.g., sex, age, medical history) data. PEO data were subjected to exploratory factor analysis (EFA) followed by confirmatory factor analysis (CFA). PEO, PEP, and PI data were used separately and in combination to differentiate diagnoses by pairwise and multinomial logistic regressions. Predicted diagnoses were compared with gold standard medical diagnoses.

RESULTS

EFA/CFA identified a 4-factor structure of the PEO based on 26/31 questionnaire items with loadings ≥0.4. Observer-reported factors alone differentiated better between syncope and epilepsy than patient-reported factors (accuracy: 96% vs 85%, p = 0.0004). Observer-reported data improved accuracy over differentiation based on patient-reported data alone from 90% to 100% between syncope and epilepsy (p = 0.005), 76% to 83% between epilepsy and PNES (p = 0.006), and 93% to 95% between syncope and PNES (p = 0.098).

CONCLUSIONS

Information from observers can make an important contribution to the differentiation of epilepsy from syncope or PNES but adds less to that of syncope from PNES.

Usefulness of head-up tilt test combined with video electroencephalogram to investigate recurrent unexplained atypical transient loss of consciousness

BACKGROUND

Convulsive syncope and epileptic seizure share many similar clinical features. Early diagnosis is critical for choosing the appropriate management strategy.

AIM

Our aim was to evaluate the diagnostic yield of an innovative diagnostic strategy - combined head-up tilt test (HUT)/video electroencephalogram (EEG) monitoring - in patients with unexplained seizure-like transient loss of consciousness (T-LOC).

METHODS

Combined HUT/video EEG was performed in patients with unexplained atypical T-LOC with both syncope and seizure characteristics remaining undiagnosed after a first-line investigation. T-LOC diagnosis was achieved in case of reproduction of usual symptoms. Events were classified as vasovagal, psychogenic or epilepsy. The link between EEG abnormalities and T-LOC was determined by an epilepsy specialist. Clinical follow-up was performed to assess T-LOC recurrence.

RESULTS

Hundred and one consecutive patients were prospectively enrolled (median age 26 [19; 46] years; 72% female) and underwent combined HUT/video EEG between 2007 and 2015. Antiepileptic drugs were being prescribed in 42% of patients. Combined HUT/video EEG was diagnostic in 67% of patients, leading to diagnosis of vasovagal syncope in 59 patients and psychogenic pseudosyncope in nine cases. Antiepileptic drugs were discontinued in 18 patients without epilepsy. Independent predictors of a definitive diagnosis were the presence of prodromal symptoms (odds ratio 5.97, 95% confidence interval 1.37-26; P=0.017) and a history of myoclonic jerks during T-LOC (odds ratio 4.36, 95% confidence interval 1.71-11.15; P=0.002).

CONCLUSIONS

Combined HUT/video EEG is useful for investigating recurrent unexplained atypical seizure-like T-LOC, especially in patients with a history of myoclonic jerks or with documented interictal non-specific EEG abnormalities.

Ictal asystole with isolated syncope: A case report and literature review

Ictal syncope is a rare phenomenon that occurs in association with 0.002-0.4% of seizures. In the absence of other symptoms, seizures presenting with syncope may be challenging to diagnose. We report a case of a previously healthy male who developed recurrent episodes of syncope with postictal confusion and was later diagnosed with temporal seizures. The patient was successfully treated with anti-seizure drugs and placement of a cardiac pacemaker. In a systematic review of literature, we summarize the clinical characteristics of patients with ictal asystole and isolated syncope. Seizures should be considered in patients with syncope of uncertain etiology.

Seizures and epilepsy in the acute medical setting: presentation and management

Epileptic seizures are a common cause for presentation to acute medical services. Whether presenting with an isolated, unprovoked seizure or with status epilepticus, a good understanding of seizures and their mimics ensures appropriate investigation and treatment. This article describes the practical aspects of the management of patients presenting with seizures to the emergency department or the acute medical unit.

Diagnostic criteria to aid the differential diagnosis of patients presenting with transient loss of consciousness: A systematic review

BACKGROUND

Transient loss of consciousness (TLOC) is a common presentation in primary care. Over 90% of these are due to epileptic seizures (ES), syncope, or psychogenic non-epileptic seizures (PNES). Misdiagnosis rates are as high as 30%.

METHODS

Systematic review of inter-ictal clinical criteria to aid differential diagnosis of TLOC. We searched Medline, EMBASE, CINAHL and PsycInfo databases, as well as relevant grey literature depositories and citations of relevant reviews and guidelines for studies giving sensitivity and specificity of inter-ictal clinical characteristics used to differentiate between causes of TLOC. Two independent reviewers selected studies for inclusion and performed critical appraisal of included articles. We performed a narrative synthesis of included studies.

RESULTS

Of 1023 results, 16 papers were included. Two compared syncope, ES, and PNES; all others compared ES and PNES. All were at significant risk of bias in at least one domain. 6 studied patient symptoms, 6 medical and social history, 3 witness reports and 1 examination findings. No individual criterion differentiated between diagnoses with high sensitivity and specificity.

CONCLUSIONS

There is a lack of validated diagnostic criteria to help clinicians assessing patients in primary or emergency care settings to discriminate between common causes of TLOC. Performance may be improved by combining sets of criteria in a clinical decision rule, but no such rule has been validated prospectively against gold-standard diagnostic criteria.

[Tips for taking the medical history in patients with syncope]

Transient loss of consciousness represents one of the most frequent reasons for patients to present in the emergency room. Already at the very beginning, the diagnostic work-up is faced with fundamental questions: (1) Was it really a loss of consciousness? (2) Which department (neurology, cardiology, or others) should check the patient? (3) Is an in-hospital diagnostic work-up required? These questions can be answered from a meticulous patient history which needs to be adjusted to the individual case but also has to systematically go through a list of questions. Patient history has to clarify whether syncope was present. Nonsyncopal events such as falls, transient global amnesia, epilepsy, psychogenic pseudosyncope, transient ischemic attack and drop attacks should be distinguished. In a second step, the four groups of causes of syncope can be assessed. Neurocardiogenic reflex syncope usually occurs with typical prodromes in typical situations in (younger) patients without heart disease. Orthostasis always occurs in upright position, typically associated with standing up and in patients treated with antihypertensive drugs. Arrhythmogenic syncope frequently shows an abrupt onset without prodromes, associated with injury and with palpitations or fast heart beat before the attack, in older patients frequently associated with known heart disease, in young patients without heart disease frequently with a family history positive for arrhythmias or sudden cardiac death. A positive history of structural cardiovascular disease should be considered as a cause of syncope, particularly if it occurs during exercise or in supine position, or is associated with chest pain or dyspnea. This review summarizes the most important questions that can elucidate the cause of syncope.

Gastric myoelectrical and neurohormonal changes associated with nausea during tilt-induced syncope

BACKGROUND

Nausea is a common prodromal symptom of neurally mediated syncope, but the biological factors linking nausea with syncope have not been studied. We aimed to characterize nausea during tilt-induced syncope by exploring related changes in gastric myoelectrical activity and plasma epinephrine, norepinephrine, and vasopressin concentrations across study phases of recumbency, tilt, syncope, and recovery.

METHODS

Electrogastrographic and plasma hormone changes were compared between patients with tilt-induced syncope and nausea (n = 18) and control subjects (n = 6) without symptoms or hemodynamic changes during tilt-table testing.

KEY RESULTS

Over a 4-minute period preceding syncope, sequential electrogastrography epochs demonstrated an increase over time in bradygastria (P = .003) and tachygastria (P = .014) power ratios, while the dominant frequency (P < .001) and the percent normogastria (P = .004) decreased. Syncope led to significant differences between cases and controls in electrogastrographic power ratios in each frequency range: bradygastria (P = .001), tachygastria (P = .005), and normogastria (P = .03). Nausea always followed electrogastrographic changes, and nausea resolution always preceded electrogastrographic normalization. Plasma vasopressin (676.5 ± 122.8 vs 91.2 ± 15.3 pg/mL, P = .012) and epinephrine (434 ± 91.3 vs 48.7 ± 2.5 pg/mL, P = .03), but not norepinephrine (P > .05), also differed with syncope between cases and controls.

CONCLUSIONS AND INFERENCES

The nausea related to tilt-induced syncope is temporally associated with changes in gastric myoelectrical activity and increases in plasma vasopressin and epinephrine. The biological mechanisms that induce syncope are physiologically distinct from other experimental models of nausea such as illusory self-motion, yet nausea with syncope appears to have similarly associated electrogastrographic and hormone changes. Thus, tilt-induced syncope could serve as an informative experimental model for nausea research.

Structural heart disease as the cause of syncope

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. During the median follow-up of 33.8±13.8 months, mean age at the qualifying syncope event was 68.3 years and 40.6% of patients were male. Syncope was vasovagal in 32%, cardiogenic in 57%, orthostatic hypotension in 6%, and of unknown causes in 5% of patients. The primary composite endpoint death, readmission, and emergency visit in 30 days was 39.4% in vasovagal syncope and 60.6% cardiogenic syncope (P<0.001). Primary endpoint-free survival was lower for patients with cardiogenic syncope (HR=2.97, 95%CI=1.94-4.55; P<0.001). The scores were analyzed for diagnostic performance with area under the curve (AUC) and did not help differentiate patients with an increased risk of adverse events. The differential diagnosis of syncope causes in patients with structural heart disease is important, because vasovagal and postural hypotension have better survival and less probability of emergency room or hospital readmission. The available scores are not reliable tools for prognosis in this specific patient population.