Reasons for Hospitalization Among Emergency Department Patients With Syncope

Role of Artificial Intelligence in Improving Syncope Management

Syncope is common in the general population and a common presenting symptom in acute care settings. Substantial costs are attributed to the 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. Although validated risk tools exist, especially for short-term prognosis, there is inconsistent application, and the current approach does not meet patient needs and 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 and hospitalisation. More recently, AI analysis of electrocardiograms 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 nontraditional data. However, steps to mitigate known problems such as generalisability, 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.

Performance of high-sensitivity cardiac troponin T in predicting major cardiovascular events in patients admitted to the emergency department for syncope with normal ECG: An observational prospective study

INTRODUCTION

History of syncope, clinical examination and electrocardiographic (ECG) findings are fundamental to assess the risk of major cardiovascular events (MACE) in patients attending the emergency department (ED) for syncope. However, in the absence of abnormal clinical examination findings or an abnormal ECG in the ED, transient rhythm or conduction disorders may not be safely excluded, hence predicting MACE remains challenging. High-sensitivity cardiac troponin T (hs-cTnT) may be a useful tool in this context.

AIM

The primary objective was to evaluate the performance of hs-cTnT in the diagnosis of MACE at 30 days in patients attending the ED for syncope with a normal initial ECG.

METHODS

This was a prospective observational cohort study that took place in the ED of a French university hospital between June 2018 and June 2019. Patients≥18 years admitted to the ED for syncope with a normal ECG were eligible. After receiving verbal consent from patients, the ED physician collected clinical and ECG data and all patients had a blood sample taken that included hs-cTnT measurement. The primary outcome was MACE within 30 days after the ED visit. MACE were evaluated by consulting the patient's medical records and telephoning patients or their general practitioners. Sensitivity, specificity, positive and negative predictive values were calculated with their 95% confidence intervals (CI) for different hs-cTnT thresholds.

RESULTS

Data from 246 patients were analysed, including 21 (9%) with MACE. Hs-cTnT had an area under the curve of 0.917 (CI: 0.872-0.962). Hs-cTnT with a threshold of 19ng/L had a sensitivity of 86% (CI: 64-97) and a specificity of 86% (CI: 81-90) for predicting MACE.

CONCLUSION

Hs-cTnT may be a relevant tool for assessing MACE risk in patients with syncope and normal ECG results.

Performance of the American Heart Association/American College of Cardiology/Heart Rhythm Society versus European Society of Cardiology guideline criteria for hospital admission of patients with syncope

BACKGROUND

Current American College of Cardiology/American Heart Association/Heart Rhythm Society (ACC/AHA/HRS) and European Society of Cardiology (ESC) guidelines recommend different strategies to avoid low-yield admissions in patients with syncope.

OBJECTIVE

The purpose of this study was to directly compare the safety and efficacy of applying admission criteria of both guidelines to patients presenting with syncope to the emergency department in 2 multicenter studies.

METHODS

The international BASEL IX (BAsel Syncope EvaLuation) study (median age 71 years) and the U.S. SRS (Improving Syncope Risk Stratification in Older Adults) study (median age 72 years) were investigated. Primary endpoints were sensitivity/specificity for the adjudicated diagnosis of cardiac syncope (BASEL IX only) and 30-day major adverse cardiovascular events (30d-MACE).

RESULTS

Among 2560 patients in the BASEL IX and 2085 in SRS studies, ACC/AHA/HRS and ESC criteria recommended admission for a comparable number of patients in BASEL IX (27% vs 28%), but ACC/AHA/HRS criteria less often in SRS (19% vs 32%; P <.01). Recommendations were discordant in ∼25% of patients. In BASEL IX, sensitivity for cardiac syncope and 30d-MACE among patients without admission criteria was comparable for ACC/AHA/HRS and ESC criteria (64% vs 65%, P = .86; and 67% vs 71%, P = .15, respectively). In SRS, sensitivity for 30d-MACE was lower with ACC/AHA/HRS (54%) vs ESC criteria (88%; P <.001). Similarly, specificity for cardiac syncope and 30d-MACE in BASEL IX was comparable for both guidelines, but in SRS the ACC/AHA/HRS guidelines showed a higher specificity for 30d-MACE than the ESC guidelines.

CONCLUSION

ACC/AHA/HRS and ESC guidelines showed disagreement regarding admission for 1 in 4 patients and had only modest sensitivity, all indicating possible opportunities for improvements.

Triage assessment of transitory loss of consciousness in the emergency department-A retrospective observational study

AIM

To establish how the Manchester Triage System can correctly prioritize patients admitted to the emergency department for transitory loss of consciousness in relation to their risk of presenting severe acute disease.

DESIGN

A observational retrospective study.

METHODS

A total of 2291 patients who required a triage evaluation for a transitory loss of consciousness at the emergency department of Merano Hospital between 1 January 2017 and 30 June 2019 were considered. Transitory loss of consciousness was classified according to European Society of Cardiology guidelines. The baseline characteristics of the patients were collected and divided according to the priority level assigned at triage into two different study groups: high priority (red/orange) and low priority (blue/green/yellow). The composite outcome of the study was defined as the diagnosis of a severe acute disease.

RESULTS

Of the patients enrolled, 17% (390/2291) had a high-priority code and 83% (1901/2291) received a low-priority code. Overall, a severe acute disease was present in 16.9% of patients (387/2291). The Manchester Triage System had a sensitivity of 42.4%, a specificity of 88.1% and an accuracy of 80.4% for predicting severe acute disease. The discriminatory ability had an area under the receiver operating characteristic curve of 0.651 (CI 95%: 0.618-0.685).

CONCLUSIONS

Despite the good specificity, the low sensitivity does not currently allow the Manchester Triage System to completely exclude patients with a severe acute disease who presented in the emergency department for a transitory loss of consciousness. Therefore, it is important to develop precise nursing tools or assessments that can improve triage performance.

IMPACT

The assessment of a complex symptom can create difficulties in the stratification of patients in triage, assigning low-priority codes to patients with a severe disease. Additional tools are needed to allow the correct triage assessment of patients presenting with transitory loss of consciousness.

Syncope in the Emergency Department: A Guide for Clinicians

Syncope is a common presenting symptom to emergency departments, but its evaluation and initial management can be challenging for ED practitioners and particularly urgent in the presence of high-risk features that increase the likelihood of cardiac etiology. Even after thorough clinical evaluation, syncope may remain unexplained. In such instances, practitioners' clinical judgment and risk assessments are critical to guide further management. In this article, evidence-informed strategies are outlined to approach the diagnosis of syncope and provide an overview of syncope clinical decision rules and shared decision-making. By incorporating risk stratification and shared decision-making into syncope care, practitioners can more confidently engage patients and families in disposition decisions to organize appropriate outpatient and follow-up care, observation, or admission.

Review article: Utility of troponin after syncope: A systematic review and meta-analysis

The role of serum troponin testing in patients presenting to the ED after syncope is unclear. The aim of this systematic review was to examine the practice and utility of troponin testing among patients presenting to the ED after syncope. We conducted a search of MEDLINE, Embase, Cochrane Library, Web of Science and Scopus databases from 1990 to February 2017 using keyword and subject headings for syncope and troponin testing. Design and results of the included studies are extracted. Studies were assessed for heterogeneity and the pooled proportion of measured troponin and positive troponin result described. There were nine studies included for analysis. Significant statistical heterogeneity among studies was observed (P < 0.001). Using the random effects model, the pooled proportion of patients presenting to the ED after syncope who had troponin measured was 0.64 (95% CI 0.46-0.82). Among patients who had been troponin tested, the pooled proportion who had a positive result was 0.19 (95% CI 0.13-0.26). Variability among reported outcomes prevented further meta-analysis. Troponin testing was commonly performed for the assessment of patients with syncope with a substantial proportion returning positive results. The correlation between raised troponin and patient outcomes was not adequately reported. It is possible that an elevated troponin may indicate serious illness, rather than myocardial damage alone.

Application of outpatient cardiac testing among emergency department patients with syncope

OBJECTIVES

2.6% of ED syncope patients will suffer cardiac serious adverse events (SAEs) within 30 days of disposition, and outpatient cardiac testing can improve patient safety. The objective is to determine whether outpatient cardiac testing for ED syncope patients is being appropriately ordered after discharge. To this end, we describe the proportion of high-risk and non-high (low and medium)-risk ED syncope patients as per the Canadian Syncope Risk Score (CSRS) who have a SAE after ED discharge, and the proportion referred for outpatient cardiac testing.

METHODS

Our multicentre prospective cohort study enrolled adult syncope patients between 2010 and 2014 in five academic EDs. We collected patient characteristics, disposition, CSRS predictors, outpatient referrals and testing results (Holter, echocardiography), and 30-day adjudicated SAE (death due to unknown/cardiac cause, myocardial infarction, arrhythmia and structural heart disease). We used descriptive statistics (mean, SD) to report our results.

RESULTS

Of 3584 enrolled patients (mean age 50.9 years, 57.7% women), 800 patients (22.3%) received an outpatient referral. Of these 800 patients, 40.3% of the non-high-risk patients (305/756) and 54.5% of the high-risk patients (24/44) received outpatient cardiac testing. Of all patients who received cardiac testing, five (1.5%; 95% CI 0.6% to 3.5%) suffered outpatient SAE (60.0% arrhythmias). Of all patients who did not receive cardiac testing, four patients (0.9%; 95% CI 0.3% to 2.2%) suffered SAE (all arrhythmias). Of the 20 (45.5%) high-risk patients who did not receive testing, two patients (10.0%; 95% CI 2.8% to 30.1%) suffered arrhythmias outside the hospital, while among the 451 (59.7%) non-high-risk patients, only two (0.4%; 95% CI 0.1% to 1.6%) suffered outpatient arrhythmias.

CONCLUSION

Outpatient cardiac testing is largely underused, especially among high-risk ED syncope patients. Better guidelines for outpatient cardiac testing are needed, as the practice is highly variable and mismatched with patient risk.

Shared Decision-Making as the Future of Emergency Cardiology

Shared decision-making is playing an increasingly large role in emergency cardiovascular care. Although there are many challenges to successfully performing shared decision-making in the emergency department, there are numerous clinical scenarios in which it should be used. In this article, we explore new research and emerging decision aids in the following emergency care scenarios: (1) low-risk chest pain; (2) new-onset atrial fibrillation; and (3) moderate-risk syncope. These decision aids are designed to engage patients and facilitate shared decision-making for specific treatment and disposition (admit vs discharge) decisions. We then offer a 3-step, practical approach to performing shared decision-making in the acute care setting, on the basis of broad stakeholder input and previous conceptual work. Step 1 involves simply acknowledging that a clinical decision needs to be made. Step 2 involves a shared discussion about the working diagnosis and the options for care in the context of the patient's values, preferences, and circumstances. The third and final step requires the patient and provider to agree on a plan of action regarding further medical care. The implementation of shared decision-making in emergency cardiology has the potential to shift the paradigm of clinical practice from paternalism toward mutualism and improve the quality and experience of care for our patients.

Predicting Short-term Risk of Arrhythmia among Patients With Syncope: The Canadian Syncope Arrhythmia Risk Score

BACKGROUND

Syncope can be caused by serious occult arrhythmias not evident during initial emergency department (ED) evaluation. We sought to develop a risk tool for predicting 30-day arrhythmia or death after ED disposition.

METHODS

We conducted a multicenter prospective cohort study at six tertiary care EDs and included adults (≥16 years) with syncope. We collected standardized variables from clinical evaluation and investigations including electrocardiogram and troponin at index presentation. Adjudicated outcomes included death or arrhythmias including procedural interventions for arrhythmia within 30 days. We used multivariable logistic regression to derive the prediction model and bootstrapping for interval validation to estimate shrinkage and optimism.

RESULTS

A total of 5,010 patients (mean ± SD age = 53.4 ± 23.0 years, 54.8% females, and 9.5% hospitalized) were enrolled with 106 (2.1%) patients suffering 30-day arrhythmia/death after ED disposition. We examined 39 variables and eight were included in the final model: lack of vasovagal predisposition, heart disease, any ED systolic blood pressure < 90 or > 180 mm Hg, troponin (>99th percentile), QRS duration > 130 msec, QTc interval > 480 msec, and ED diagnosis of cardiac/vasovagal syncope (optimism corrected C-statistic 0.90 [95% CI = 0.87-0.93]; Hosmer-Lemeshow p = 0.08). The Canadian Syncope Arrhythmia Risk Score had a risk ranging from 0.2% to 74.5% for scores of -2 to 8. At a threshold score of ≥0, the sensitivity was 97.1% (95% CI = 91.6%-99.4%) and specificity was 53.4% (95% CI = 52.0%-54.9%).

CONCLUSIONS

The Canadian Syncope Arrhythmia Risk Score can improve patient safety by identification of those at risk for arrhythmias and aid in acute management decisions. Once validated, the score can identify low-risk patients who will require no further investigations.