Canadian Cardiovascular Society Clinical Practice Update on the Assessment and Management of Syncope

Role of Artificial Intelligence in Improving Syncope Management

Syncope is common in the general population and is a common presenting symptom in acute care settings. Substantial costs are attributed to care of patients with syncope. Current challenges include differentiating syncope from its mimickers, identifying serious underlying conditions that caused the syncope, and wide variations in current management. While validated risk tools exist especially for short-term prognosis, there is inconsistent application, and the current approach does not meet the patient needs/expectations. Artificial intelligence (AI) techniques such as machine learning methods including natural language processing can potentially address the current challenges in syncope management. Preliminary evidence from published studies indicates that it is possible to accurately differentiate syncope from its mimickers and predict short-term prognosis/ hospitalization. More recently AI analysis of ECG has shown promise in detection of serious structural and functional cardiac abnormalities which has the potential to improve syncope care. Future AI studies have the potential to address current issues in syncope management. AI can automatically prognosticate risk in real time by accessing traditional and non-traditional data. However, steps to mitigate known problems such generalizability, patient privacy, data protection, and liability will be needed. In the past AI has had limited impact due to underdeveloped analytical methods, lack of computing power, poor access to powerful computing systems, and availability of reliable high-quality data. All impediments except data have been solved. AI will live up to its promise to transform syncope care if the health care system can satisfy AI requirement of large scale, robust, accurate, and reliable data.

Syncope and Traffic Crash: A Population-Based Case-Crossover Analysis

BACKGROUND

Among individuals with recent syncope, recurrence of syncope while driving might incapacitate a driver and cause a motor vehicle crash. Current driving restrictions assume that some forms of syncope transiently increase crash risk. We evaluated whether syncope is associated with a transient increase in crash risk.

METHODS

We performed a case-crossover analysis of linked administrative health and driving data from British Columbia, Canada (2010 to 2015). We included licensed drivers who visited an emergency department with "syncope and collapse" and who were involved as a driver in an eligible motor vehicle crash, both within the study interval. Using conditional logistic regression, we compared the rate of emergency visits for syncope in the 28 days before crash (the "pre-crash interval") with the rate of emergency visits for syncope in 3 self-matched 28-day control intervals (ending 6, 12, and 18 months before the crash).

RESULTS

Among eligible crash-involved drivers, 47 of 3026 pre-crash intervals and 112 of 9078 control intervals had emergency visits for syncope, indicating syncope was not significantly associated with subsequent crash (1.6% vs 1.2%; adjusted odds ratio [OR], 1.27; 95% confidence interval [CI], 0.90-1.79; P = 0.18). There was no significant association between syncope and crash in subgroups at higher risk for adverse outcomes after syncope (eg, age > 65 years, cardiovascular disease, cardiac syncope).

CONCLUSIONS

In the context of prevailing modifications of driving behaviour after syncope, an emergency department visit for syncope did not transiently increase the risk of subsequent traffic collision. Overall crash risks after syncope appear to be adequately addressed by current driving restrictions.

Canadian Cardiovascular Society 2023 Guidelines on the Fitness to Drive

Cardiovascular conditions are among the most frequent causes of impairment to drive, because they might induce unpredictable mental state alterations via diverse mechanisms like myocardial ischemia, cardiac arrhythmias, and vascular dysfunction. Accordingly, health professionals are often asked to assess patients' fitness to drive (FTD). The Canadian Cardiovascular Society previously published FTD guidelines in 2003-2004; herein, we present updated FTD guidelines. Because there are no randomized trials on FTD, observational studies were used to estimate the risk of driving impairment in each situation, and recommendations made on the basis of Canadian Cardiovascular Society Risk of Harm formula. More restrictive recommendations were made for commercial drivers, who spend longer average times behind the wheel, use larger vehicles, and might transport a larger number of passengers. We provide guidance for individuals with: (1) active coronary artery disease; (2) various forms of valvular heart disease; (3) heart failure, heart transplant, and left ventricular assist device situations; (4) arrhythmia syndromes; (5) implantable devices; (6) syncope history; and (7) congenital heart disease. We suggest appropriate waiting times after cardiac interventions or acute illnesses before driving resumption. When short-term driving cessation is recommended, recommendations are on the basis of expert consensus rather than the Risk of Harm formula because risk elevation is expected to be transient. These recommendations, although not a substitute for clinical judgement or governmental regulations, provide specialists, primary care providers, and allied health professionals with a comprehensive list of a wide range of cardiac conditions, with guidance provided on the basis of the level of risk of impairment, along with recommendations about ability to drive and the suggested duration of restrictions.

Syncope While Driving and the Risk of a Subsequent Motor Vehicle Crash

STUDY OBJECTIVE

Syncope that occurs while driving can result in a motor vehicle crash. Whether individuals with a prior syncope-related crash exhibit an exceptional risk of subsequent crash remains uncertain.

METHODS

We performed a population-based retrospective observational study of patients diagnosed with 'syncope and collapse' at any of 6 emergency departments in British Columbia, Canada (2010 to 2015). Data were obtained from chart abstraction, administrative health records, insurance claims and police crash reports. We compared crash-free survival among individuals with crash-associated syncope (a crash and an emergency visit for syncope on the same date) to that among controls with syncope alone (no crash on date of emergency visit for syncope).

RESULTS

In the year following their index emergency visit, 13 of 63 drivers with crash-associated syncope and 852 of 9,160 controls with syncope alone experienced a subsequent crash as a driver (crash risk 21% versus 9%). After accounting for censoring and potential confounders, crash-associated syncope was not associated with a significant increase in the risk of subsequent crash (adjusted hazard ratio [aHR] 1.38, 95% confidence interval [CI] 0.78 to 2.47). Individuals with crash-associated syncope were 31-fold more likely to have physician driving advice documented during their index visit (prevalence ratio 31.0, 95% CI, 21.3 to 45.1). In the subgroup without documented driving advice, crash-associated syncope was associated with a significant increase in subsequent crash risk (aHR 1.88, 95% CI 1.06 to 3.36).

CONCLUSIONS

Crash risk after crash-associated syncope appears similar to crash risk after syncope alone.

Cardioneuroablation for successful treatment of symptomatic bradycardia in a 12-year-old child after a 6-month follow-up

Background

Cardioneuroablation (CNA) is recognized as a promising therapeutic option for adults with severe symptomatic bradycardia caused by excessive vagal tone. However, no pediatric cases have been reported to date. Therefore, the aim of this study is to evaluate the feasibility and efficacy of CNA in children.

Methods

A 12-year-old male patient was hospitalized with symptoms of fatigue, palpitations, and syncope for more than 2 months, and was definitively diagnosed with functional sinoatrial node dysfunction by using a 12-lead electrocardiogram, 24-h Holter monitoring, loading dose of atropine test (0.04 mg/kg), and treadmill exercise test. Simultaneously, whole-exome sequencing was performed on the child and his core family members. After completing the preoperative examination and signing the informed consent form, the child underwent CNA therapy.

Results

First, the electroanatomic structures of both atria were mapped out by using the Carto 3 system, according to the protocol of purely anatomy-guided and local fractionated intracardiac electrogram-guided CNA methods. Then, the local fractionated intracardiac electrograms of each cardiac ganglionated plexus (GP), including the GP between the aortic root and the medial wall of the superior vena cava, the GP between the posterior wall of the coronary sinus ostium and the left atrium, the GP between the anterior antrum of the right superior pulmonary vein and the superior vena cava, the GP in the superolateral area around the root of the left superior pulmonary vein, the GP around the root of the right inferior pulmonary vein, and the GP around the root of the left inferior pulmonary vein, were used as targets for ablation at a power of 30 W with an ablation index of 350-400. At a 6-month follow-up, the child's heart rhythm saw a complete restoration to sinus rhythm and clinical symptoms disappeared.

Conclusion

The first application of CNA in a child with symptomatic sinus bradycardia was achieved with better clinical outcomes. CNA can be carried out cautiously in children under suitable indications.

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.

Development of practice recommendations based on the Canadian Syncope Risk Score and identification of barriers and facilitators for implementation

BACKGROUND

Wide variations in emergency department (ED) syncope management exist. The Canadian Syncope Risk Score (CSRS) was developed to predict the probability of 30-day serious outcomes after ED disposition. Study objectives were to evaluate the acceptability of proposed CSRS practice recommendations among providers and patients, and identify barriers and facilitators for CSRS use to guide disposition decisions.

METHODS

We conducted semi-structured interviews with 41 physicians involved in ED syncope and 35 ED patients with syncope. We used purposive sampling to ensure a variety of physician specialties and CSRS patient risk levels. Thematic analysis was completed by two independent coders with consensus meetings to resolve conflicts. Analysis proceeded in parallel with interviews until data saturation.

RESULTS

The majority (97.6%; 40/41) of physicians agreed with discharge of low risk (CSRS ≤ 0) but opined that 'no follow up' changed to 'follow-up as needed'. Physicians indicated current practices do not align with the medium-risk recommendation to discharge patients with 15-day monitoring (CSRS = 1-3; due to lack of access to monitors and timely follow-up) and the high-risk recommendation (CSRS ≥ 4) to potentially discharge patients with 15-day monitoring. Physicians recommended brief hospitalization of high-risk patients due to patient safety concerns. Facilitators included the CSRS-based patient education and scores supporting their clinical gestalt. Patients reported receiving varying levels of information regarding syncope and post-ED care, were satisfied with care received and preferred less resource intensive options.

CONCLUSION

Our recommendations based on the study results were: discharge of low-risk patients with physician follow-up as needed; discharge of medium-risk patients with 15-day cardiac monitoring and brief hospitalization of high-risk patients with 15-day cardiac monitoring if discharged. Patients preferred less resource intensive options, in line with CSRS recommended care. Implementation should leverage identified facilitators (e.g., patient education) and address the barriers (e.g., monitor access) to improve ED syncope care.

Syncope and subsequent traffic crash: A responsibility analysis

BACKGROUND

Physicians are often asked to counsel patients about driving safety after syncope, yet little empirical data guides such advice.

METHODS

We identified a population-based retrospective cohort of 9,507 individuals with a driver license who were discharged from any of six urban emergency departments (EDs) with a diagnosis of 'syncope and collapse'. We examined all police-reported crashes that involved a cohort member as a driver and occurred between 1 January 2010 and 31 December 2016. We categorized crash-involved drivers as 'responsible' or 'non-responsible' for their crash using detailed police-reported crash data and a validated responsibility scoring tool. We then used logistic regression to test the hypothesis that recent syncope was associated with driver responsibility for crash.

RESULTS

Over the 7-year study interval, cohort members were involved in 475 police-reported crashes: 210 drivers were deemed responsible and 133 drivers were deemed non-responsible for their crash; the 132 drivers deemed to have indeterminate responsibility were excluded from further analysis. An ED visit for syncope occurred in the three months leading up to crash in 11 crash-responsible drivers and in 5 crash-non-responsible drivers, suggesting that recent syncope was not associated with driver responsibility for crash (adjusted odds ratio, 1.31; 95%CI, 0.40-4.74; p = 0.67). However, all drivers with cardiac syncope were deemed responsible, precluding calculation of an odds ratio for this important subgroup.

CONCLUSIONS

Recent syncope was not significantly associated with driver responsibility for traffic crash. Clinicians and policymakers should consider these results when making fitness-to-drive recommendations after syncope.

Cardioneuroablation for vasovagal syncope: A systematic review and meta-analysis

BACKGROUND

Cardioneuroablation (CNA) has emerged as promising therapy for patients with refractory vasovagal syncope (VVS).

OBJECTIVE

The purpose of this study was to provide a freedom from syncope estimate for CNA, including subgroup analysis by method and target of ablation.

METHODS

A systematic search was performed in MEDLINE and EMBASE according to the PRISMA guidelines until February 14, 2022. Observational studies and clinical trials reporting freedom from syncope were included. Meta-analysis was performed with a random-effects model.

RESULTS

A total of 465 patients were included across 14 studies (mean age 39.8 ± 4.0 year; 53.5% female). Different techniques were used to guide CNA: 50 patients (10.8%) by mapping fractionated electrograms, 73 (15.7%) with the spectral method, 210 (45.2%) with high-frequency stimulation, 73 (15.7%) with a purely anatomically guided method, and 59 (12.6%) with a combination. The target was biatrial in 168 patients (36.1%), left atrium only in 259 (55.7%), and right atrium only in 38 (8.2%). The freedom from syncope was 91.9% (95% confidence interval [CI] 88.1%-94.6%; I2 = 6.9%; P = .376). CNA limited to right atrial ablation was associated with a significant lower freedom from syncope (81.5%; 95% CI 51.9%-94.7%; P <.0001) vs left atrial ablation only (94.0%; 95% CI 88.6%--6.9%) and biatrial ablation (92.7%; 95% CI 86.8%-96.1%). Subgroup analysis according to the technique used to identify ganglionated plexi did not show any significant difference in freedom from syncope (P = .206).

CONCLUSION

This meta-analysis suggests a high freedom from syncope after CNA in VVS. Well-designed, double-blind, multicenter, sham-controlled randomized clinical trials are needed to provide evidence for future guidelines.

Syncope and the Risk of Subsequent Motor Vehicle Crash: A Population-Based Retrospective Cohort Study

IMPORTANCE

Medical driving restrictions are burdensome, yet syncope recurrence while driving can cause a motor vehicle crash (MVC). Few empirical data inform current driving restrictions after syncope.

OBJECTIVE

To examine MVC risk among patients visiting the emergency department (ED) after first-episode syncope.

DESIGN, SETTING, AND PARTICIPANTS

A population-based, retrospective observational cohort study of MVC risk after first-episode syncope was performed in British Columbia, Canada. Patients visiting any of 6 urban EDs for syncope and collapse were age- and sex-matched to 4 control patients visiting the same ED in the same month for a condition other than syncope. Patients' ED medical records were linked to administrative health records, driving history, and detailed crash reports. Crash-free survival among individuals with syncope was then compared with that among matched control patients. Data analyses were performed from May 2020 to March 2022.

EXPOSURES

Initial ED visit for syncope.

MAIN OUTCOMES AND MEASURES

Involvement as a driver in an MVC in the year following the index ED visit. Crashes were identified using insurance claim data and police crash reports.

RESULTS

The study cohort included 43 589 patients (9223 patients with syncope and 34 366 controls; median [IQR] age, 54 [35-72] years; 22 360 [51.3%] women; 5033 [11.5%] rural residents). At baseline, crude MVC incidence rates among both the syncope and control groups were higher than among the general population (12.2, 13.2, and 8.2 crashes per 100 driver-years, respectively). In the year following index ED visit, 846 first crashes occurred in the syncope group and 3457 first crashes occurred in the control group, indicating no significant difference in subsequent MVC risk (9.2% vs 10.1%; adjusted hazard ratio [aHR], 0.93; 95% CI, 0.87-1.01; P = .07). Subsequent crash risk among patients with syncope was not significantly increased in the first 30 days after index ED visit (aHR, 1.07; 95% CI, 0.84-1.36; P = .56) or among subgroups at higher risk of adverse events after syncope (eg, age >65 years; cardiogenic syncope; Canadian Syncope Risk Score ≥1).

CONCLUSIONS AND RELEVANCE

The findings of this population-based retrospective cohort study suggest that patients visiting the ED with first-episode syncope exhibit a subsequent crash risk no different than the average ED patient. More stringent driving restrictions after syncope may not be warranted.

Cardiac and Vascular Causes of Syncope and Atherosclerosis

PURPOSE OF REVIEW

Among the most common causes of cardiac syncope are arrhythmias and ischemic heart disease, both of which can coexist. The purpose of this review is to discuss the main causes of cardiac and vascular syncope related to atherosclerosis, its epidemiological and clinical aspects, warning signs, and initial approach.

RECENT FINDINGS

Cardiac syncope may have a frequency of up to 34% in elderly people. Atherosclerosis-related causes of cardiac and vascular syncope may be due to cardiac arrhythmia and/or structural impairment of the heart or arteries. Late ventricular tachycardia and late-onset high-grade atrioventricular block associated with myocardial ischemia may occur with syncope, which is related to higher mortality. Besides ventricular dysfunction, concentric remodeling is also a prognostic factor. In calcific degenerative aortic stenosis, syncope carries a worse prognosis than the other cardinal signs. Cardiac syncope has a high recurrence and mortality rate. There are red flag alerts that must be considered in risk stratification.

Extracardiac Vagal Stimulation-Assisted Cardioneuroablation: Dynamically Evaluating the Impact of Sequential Ganglionated Plexus Ablation on Vagal Control of SAN and AVN in Patients with Sinoatrial Node Dysfunction

Cardioneuroablation (CNA) is proposed as a promising therapy for patients with sinoatrial node dysfunction (SND) that is mediated by excessive vagal tone. However, a series of urgent questions about CNA remain unanswered. From December 2020 to March 2022, six patients with symptomatic SND who underwent CNA were summarized in this report. Sequential CNA targeting Ao-SVC GP, PMLGP, RAGP, and LSGP was performed in patients, guided by fractionated intracardiac electrograms and dynamically evaluated by extracardiac vagal stimulation (ECVS). The results showed that Ao-SVC GP ablation led to a significant increase in heart rate (HR) and the elimination of sinus arrest evoked by ECVS, while the vagal responses of atrial ventricular block were eliminated by the ablation of PMLGP and LSGP. Post-procedure HR increased up to 64-86% of the maximum HR of an atropine test at baseline. The median HR from Holter monitoring increased from 52.8 ± 2.1 bpm at baseline to 73.0 ± 10.4 bpm after the procedure (p = 0.012) and to 71.3 ± 10.1 bpm at the six-month follow-up (p = 0.011). Bradycardia-related symptoms disappeared in all patients at the six-month follow-up. This case series reveals the feasibility of using the ECVS-assisted sequential CNA technique and indicates the critical role of ECVS in dynamically evaluating the impact of sequential CNA on the vagal control of SAN and AVN.

Cardioneuroablation for Vasovagal Syncope and Atrioventricular Block: A Step-by-Step Guide

Catheter based cardioneuroablation is increasingly being utilized to improve outcomes in patients with vasovagal syncope and atrioventricular block due to vagal hyperactivity. There is now increasing convergence amongst enthusiasts on its various aspects, including patient selection, technical steps, and procedural end-points. This pragmatic review aims to take the reader through a step-by-step approach to cardioneuroablation: we begin with a brief overview of the anatomy of intrinsic cardiac autonomic nervous system, before focusing on the indications, pre- and post-procedure management, necessary equipment, and its potential limitations. This article is protected by copyright. All rights reserved.

Syncope: Diagnostic Yield of Various Clinical Investigations

Objective: The present study was designed to evaluate the clinical profile of patients with syncope and the usefulness of various tests to reach a diagnosis of syncope and its etiology.

Methods: This was a cross-sectional, observational study that enrolled 90 consecutive patients (aged ≥ 12 years) who presented with syncope. Detailed information was obtained from each enrolled patient on history and physical examination. All patients underwent electrocardiography (ECG) and echocardiographic examination. Other specific tests were also performed based on the findings from medical history, physical examination, ECG, and echocardiography findings.

Results: Among 90 patients with syncope, 45% were males, and age distribution showed a bimodal distribution with two peaks. A total of 67% and 5% of patients had past history of syncope and injury due to syncope, respectively. Of the patients, 38% underwent Holter monitoring, 79 (87%) underwent head-up tilt table test (HUTT) test, 8% underwent treadmill test, 36% underwent CT/MRI of the brain, 25% underwent electroencephalography, 40% underwent carotid sinus massage, 7% underwent coronary angiography, 3% underwent electrophysiological study, and 3% of patients underwent carotid Doppler ultrasound. The commonly noted syncope was vasovagal/neutrally mediated syncope (68%). However, the etiology of syncope could not be determined in six (7%) patients.

Conclusion: This study concluded that the initial evaluation of patients with syncope should focus on history, physical examination, and ECG examination. Information obtained from such basic evaluations should be used to guide the selection of further high yield tests to reduce the cost of evaluation and for appropriate workup for the diagnosis of syncope.

Clinical electrophysiology of the aging heart

INTRODUCTION

Advancements in medical and consumer-grade technologies have made it easier than ever to monitor a patient's heart rhythm and to diagnose arrhythmias. Octogenarians with symptomatic arrhythmias have unique management challenges due to their frailty, complex drug interactions, cognitive impairment, and competing comorbidities. The management decisions are further complicated by the lack of randomized evidence to guide treatment.

AREAS COVERED

A comprehensive literature review was undertaken to outline various tachyarrhythmias and bradyarrhythmias and their management, the role of cardiac implantable electronic devices, cardiac ablations, and specific geriatric arrhythmia considerations as recommended in international guidelines.

EXPERT OPINION

Atrial fibrillation (AF) is arguably the most important arrhythmia in the elderly and is associated with significant morbidity and mortality. Early diagnosis of AF, potentially with smart devices (wearables), has the potential to reduce the incidence of stroke, systemic emboli, and the risk of dementia. Bradyarrhythmias have a high incidence in the elderly as well, often requiring implantation of a permanent pacemaker. Leadless pacemakers implanted directly into the right ventricle are great options for gaining traction in elderly patients.

Syncope and the aging patient: Navigating the challenges

Syncope in the elderly patient is a common presentation and the most common causes are usually non-cardiac. Older adults however are more challenging dilemmas as their presentation is complicated by co-morbidities, mainly cardiovascular and neurodegenerative disorders. Frailty and cognitive impairment add to the ambiguity of the presentation, and polypharmacy is often a major modifiable contributing factor. Vasovagal syncope is a common presentation throughout life even as we age. It has a favorable prognosis and conservative management usually suffices. Vasovagal syncope in this population may be misdiagnosed as accidental falls and is frequently associated with injury, as is carotid sinus syndrome. The initial approach to these patients entails a detailed history and physical examination including a comprehensive medication history, orthostatic vital signs, and a 12-lead electrocardiogram. Further cardiac and neuroimaging rarely helps, unless directed by specific clinical findings. Head-up tilt testing and carotid sinus massage retain their diagnostic accuracy and safety in the elderly, and implantable loop recorders provide important information in many elderly patients with unexplained falls and syncope. The starting point in management of this population with non-cardiac syncope is attempting to withdraw unnecessary vasoactive and psychotropic medications. Non-pharmacologic and pharmacologic therapy for syncope in the elderly has limited efficacy and safety concerns. In selected patients, pacemaker therapy might offer symptomatic relief despite lack of efficacy when vasodepression is prominent. An approach focused on primary care with targeted specialist referral seems a safe and effective strategy.

Management of vasovagal syncope

Vasovagal syncope (VVS) is a very common form of fainting. Treatment begins with patient education about the mechanism of fainting, and the non-lethal nature of vasovagal syncope. In this article, we review several non-pharmacological approaches that form the foundation of our current treatments. These include increases in dietary salt and water intake, the use of compression garments, physical counter-maneuvers and tilt-training. When these approaches are inadequate, medications can sometimes be effective. While the evidence base for the pharmacological treatment of VVS is modest, recent trial data have found drugs to be useful in placebo-controlled randomized trials. For select patients, and those patients more refractory to medications, procedural treatments may be an option. In this review, we discuss the current state of evidence for the non-pharmacological and pharmacological treatments for VVS, as well as some novel, emerging therapies for VVS.

Clinician needs and perceptions about cardioneuroablation for recurrent vasovagal syncope: An international clinician survey

BACKGROUND

Cardioneuroablation (CNA) targets the intrinsic cardiac autonomic nervous system ganglionated plexi located in the peri-atrial epicardial fat. There is increasing interest in CNA as a treatment of vasovagal syncope (VVS), despite no randomized clinical trial (RCT) data.

OBJECTIVE

The purpose of this study was to poll the opinion on CNA) for VVS.

METHODS

A REDCap (Research Electronic Data Capture) survey was administered to international physicians treating patients with VVS on their opinion about patient selection criteria, ablation approach, RCT design, and most appropriate end points for CNA procedures.

RESULTS

The survey was completed by 118 physicians; 86% were cardiac electrophysiologists. The majority of respondents (79%) would consider referring a patient with refractory VVS for CNA, and 27% have performed CNA for VVS themselves. Most felt patient selection should require a head-up tilt test with a cardioinhibitory response (67%) and suggest a minimum age of 18 years with a median of 3 (interquartile range 2-5) episodes in the past year. There were differences in patient selection between physicians who have performed CNA themselves and those who have not. The majority felt that the ablation strategy should include both atria (70%) with an anatomical approach in combination with autonomic stimulation (85%). Performing a sham procedure in the control arm was supported by 56% of respondents, providing equipoise in RCT design. The preferred primary outcome was freedom from syncope within 1 year of follow-up.

CONCLUSION

There is widespread support for well-designed RCTs to confirm the hypothesized clinical benefit of CNA, provide data to guide the risk-benefit equations during patient selection, and appropriately estimate the placebo effect.

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.

National Trends of Gender Disparity in Canadian Cardiovascular Society Guideline Authors, 2001-2020

Background

The level of representation of women in cardiology remains low compared to that of men, particularly in leadership positions. We evaluated gender disparity in the authorship of Canadian Cardiovascular Society (CCS) guidelines.

Methods

All CCS guidelines from 2001-2020 were identified. Gender was assessed based on pronoun use in the biographies and social media of the authors. Only primary panel authors were included in our analysis. Stratified analyses were performed based on subspecialties.

Results

A total of 76 guidelines were identified, with 1172 authors (26% women, 74% men, P < 0.0001), with no significant change in percentage of women authors over 2 decades, (37.1% in 2001, 36.3% in 2020, P = 0.34). Inclusion of women as authors occurred less frequently than inclusion of men in general cardiology guidelines (20.1% vs 79.9%, P < 0.0001) and all subspecialties—heart failure (36.4% vs 63.6%, P < 0.0001), interventional cardiology (12.6% vs 87.4%, P < 0.0001), electrophysiology (20.2% vs 79.8%, P < 0.0001), and pediatric cardiology (41.7% vs 58.3%, P = 0.02). It was less likely for women to be a chair or cochair of a guideline writing committee, compared with men (20.1% vs 79.8%, P < 0.0001). There were 609 unique authors (25.6% women, 74.4% men, P < 0.0001), 542 unique medical doctorate (MD) authors (20.7% women, 79.3% men, P < 0.0001), and 67 unique non-MD authors (65.7% women, 34.3% men, P = 0.0003).

Conclusions

There is a persistent shortfall in the inclusion of women authors for CCS guidelines, which has not changed over time. Further efforts are required to promote women's inclusion in leadership roles, which may lead to authorship of the guidelines.