Derivation of a risk scale and quantification of risk factors for serious adverse events in adult emergency department syncope patients

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.

Risk stratification tools for patients with syncope in emergency medical services and emergency departments: a scoping review

BACKGROUND

Patients with a syncope constitute a challenge for risk stratification in (prehospital) emergency care. Professionals in EMS and ED need to differentiate the high-risk from the low-risk syncope patient, with limited time and resources. Clinical decision rules (CDRs) are designed to support professionals in risk stratification and clinical decision-making. Current CDRs seem unable to meet the standards to be used in the chain of emergency care. However, the need for a structured approach for syncope patients remains. We aimed to generate a broad overview of the available risk stratification tools and identify key elements, scoring systems and measurement properties of these tools.

METHODS

We performed a scoping review with a literature search in MEDLINE, CINAHL, Pubmed, Embase, Cochrane and Web of Science from January 2010 to May 2022. Study selection was done by two researchers independently and was supervised by a third researcher. Data extraction was performed through a data extraction form, and data were summarised through descriptive synthesis. A quality assessment of included studies was performed using a generic quality assessment tool for quantitative research and the AMSTAR-2 for systematic reviews.

RESULTS

The literature search identified 5385 unique studies; 38 were included in the review. We discovered 19 risk stratification tools, one of which was established in EMS patient care. One-third of risk stratification tools have been validated. Two main approaches for the application of the tools were identified. Elements of the tools were categorised in history taking, physical examination, electrocardiogram, additional examinations and other variables. Evaluation of measurement properties showed that negative and positive predictive value was used in half of the studies to assess the accuracy of tools.

CONCLUSION

A total of 19 risk stratification tools for syncope patients were identified. They were primarily established in ED patient care; most are not validated properly. Key elements in the risk stratification related to a potential cardiac problem as cause for the syncope. These insights provide directions for the key elements of a risk stratification tool and for a more advanced process to validate risk stratification tools.

Multivariable risk scores for predicting short-term outcomes for emergency department patients with unexplained syncope: A systematic review

OBJECTIVES

Emergency department (ED) patients with unexplained syncope are at risk of experiencing an adverse event within 30 days. Our objective was to systematically review the accuracy of multivariate risk stratification scores for identifying adult syncope patients at high and low risk of an adverse event over the next 30 days.

METHODS

We conducted a systematic review of electronic databases (MEDLINE, Cochrane, Embase, and CINAHL) from database creation until May 2020. We sought studies evaluating prediction scores of adults presenting to an ED with syncope. We included studies that followed patients for up to 30 days to identify adverse events such as death, myocardial infarction, stroke, or cardiac surgery. We only included studies with a blinded comparison between baseline clinical features and adverse events. We calculated likelihood ratios and confidence intervals (CIs).

RESULTS

We screened 13,788 abstracts. We included 17 studies evaluating nine risk stratification scores on 24,234 patient visits, where 7.5% (95% CI = 5.3% to 10%) experienced an adverse event. A Canadian Syncope Risk Score (CSRS) of 4 or more was associated with a high likelihood of an adverse event (LR_score≥4  = 11, 95% CI = 8.9 to 14). A CSRS of 0 or less (LR_score≤0  = 0.10, 95% CI = 0.07 to 0.20) was associated with a low likelihood of an adverse event. Other risk scores were not validated on an independent sample, had low positive likelihood ratios for identifying patients at high risk, or had high negative likelihood ratios for identifying patients at low risk.

CONCLUSION

Many risk stratification scores are not validated or not sufficiently accurate for clinical use. The CSRS is an accurate validated prediction score for ED patients with unexplained syncope. Its impact on clinical decision making, admission rates, cost, or outcomes of care is not known.

Diagnostic accuracy of the Ottawa 3DY and Short Blessed Test to detect cognitive dysfunction in geriatric patients presenting to the emergency department

OBJECTIVES

Cognitive dysfunction (CD) is a common finding in geriatric patients presenting to the emergency department (ED). Our primary objective was to determine the diagnostic accuracy of the Ottawa 3DY (O3DY) and Short Blessed Test (SBT) as screening tools for the detection of CD in the ED. Our secondary objective was to estimate the inter-rater reliability of these instruments.

METHODS

We conducted a prospective cross-sectional comparative study at an inner-city academic medical centre (annual ED visit census 86 000). Patients aged 75 years or greater were evaluated for inclusion, 163 were screened, 150 were deemed eligible and 117 were enrolled. The research team completed the O3DY, SBT and Mini-Mental State Exam (MMSE) for each participant. Descriptive statistics were calculated. Sensitivity and specificity of the O3DY and SBT were calculated in STATA V.11.2 using the MMSE as our criterion standard.

RESULTS

We enrolled 117 patients from June to November 2016. The median ED length of stay at the time of completion of all tests was 1:40 (IQR 1:34-1:46). The sensitivity of the O3DY was 71.4% (95% CI 47.8 to 95.1), and specificity was 56.3% (46.7-65.9). Sensitivity of the SBT was 85.7% (67.4-99.9) and specificity was 58.3% (48.7-67.8). The receiver operating characteristic area under the curve was calculated for the O3DY (0.51; 95% CI 0.42 to 0.61) and SBT (0.52; 95% CI 0.43 to 0.61) relative to the MMSE. Inter-rater reliability for the O3DY (k=0.64) and SBT (k=0.63) were good.

CONCLUSION

In a cohort of geriatric patients presenting to an inner-city academic ED, the O3DY and SBT tools demonstrate moderate sensitivity and specificity for the detection of CD. Inter-rater reliability for the O3DY and SBT were good. Future research on this topic should attempt to derive and validate ED-specific screening tools, which will hopefully result in more robust likelihood ratios for the screening of CD in ED geriatric patients.

Predictors of Short-Term Outcomes after Syncope: A Systematic Review and Meta-Analysis

Introduction

We performed a systematic review and meta-analysis to identify predictors of serious clinical outcomes after an acute-care evaluation for syncope.

Methods

We identified studies that assessed for predictors of short-term (≤30 days) serious clinical events after an emergency department (ED) visit for syncope. We performed a MEDLINE search (January 1, 1990 – July 1, 2017) and reviewed reference lists of retrieved articles. The primary outcome was the occurrence of a serious clinical event (composite of mortality, arrhythmia, ischemic or structural heart disease, major bleed, or neurovascular event) within 30 days. We estimated the sensitivity, specificity, and likelihood ratio of findings for the primary outcome. We created summary estimates of association on a variable-by-variable basis using a Bayesian random-effects model.

Results

We reviewed 2,773 unique articles; 17 met inclusion criteria. The clinical findings most predictive of a short-term, serious event were the following: 1) An elevated blood urea nitrogen level (positive likelihood ratio [LR+]: 2.86, 95% confidence interval [CI] [1.15, 5.42]); 2); history of congestive heart failure (LR+: 2.65, 95%CI [1.69, 3.91]); 3) initial low blood pressure in the ED (LR+: 2.62, 95%CI [1.12, 4.9]); 4) history of arrhythmia (LR+: 2.32, 95%CI [1.31, 3.62]); and 5) an abnormal troponin value (LR+: 2.49, 95%CI [1.36, 4.1]). Younger age was associated with lower risk (LR−: 0.44, 95%CI [0.25, 0.68]). An abnormal electrocardiogram was mildly predictive of increased risk (LR+ 1.79, 95%CI [1.14, 2.63]).

Conclusion

We identified specific risk factors that may aid clinical judgment and that should be considered in the development of future risk-prediction tools for serious clinical events after an ED visit for syncope.

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.

CAEP 2014 Academic symposium: "How to make research succeed in your department: How to fund your research program"

OBJECTIVE

We sought to gather a comprehensive list of funding strategies and opportunities for emergency medicine (EM) centres across Canada, and make recommendations on how to successfully fund all levels of research activity, including research projects, staff salaries, infrastructure, and researcher stipends.

METHODS

We formed an expert panel consisting of volunteers recognized nationally for their scholarly work in EM. First, we conducted interviews with academic leaders and researchers to obtain a description of their local funding strategies using a standardized open-ended questionnaire. Panelists then identified emerging funding models. Second, we listed funding opportunities and initiatives at the provincial, national, and international levels. Finally, we used an iterative consensus-based approach to derive pragmatic recommendations after incorporating comments and suggestions from participants at an academic symposium.

RESULTS

Our review of funding strategies identified four funding models: 1) investigator dependent model, 2) practice plan, 3) generous benefactor, and 4) mixed funding. Recommendations in this document include approaches for research contributors and producers (seven recommendations), for local academic leaders (five recommendations), and for national organizations, such as the Canadian Association of Emergency Physicians (CAEP) (three recommendations).

CONCLUSIONS

Funding for research in EM varies across Canada and is largely insecure. We offer recommendations to help facilitate funding for large and small projects, for salary support, and for local and national leaders to advance EM research. We believe that these recommendations will increase funding for all levels of EM research activity, including research projects, staff salaries, infrastructure, and researcher stipends.

Development of the Canadian Syncope Risk Score to predict serious adverse events after emergency department assessment of syncope

BACKGROUND

Syncope can be caused by serious conditions not evident during initial evaluation, which can lead to serious adverse events, including death, after disposition from the emergency department. We sought to develop a clinical decision tool to identify adult patients with syncope who are at risk of a serious adverse event within 30 days after disposition from the emergency department.

METHODS

We prospectively enrolled adults (age ≥ 16 yr) with syncope who presented within 24 hours after the event to 1 of 6 large emergency departments from Sept. 29, 2010, to Feb. 27, 2014. We collected standardized variables at index presentation from clinical evaluation and investigations. Adjudicated serious adverse events included death, myocardial infarction, arrhythmia, structural heart disease, pulmonary embolism, serious hemorrhage and procedural interventions within 30 days.

RESULTS

We enrolled 4030 patients with syncope; the mean age was 53.6 years, 55.5% were women, and 9.5% were admitted to hospital. Serious adverse events occurred in 147 (3.6%) of the patients within 30 days after disposition from the emergency department. Of 43 candidate predictors examined, we included 9 in the final model: predisposition to vasovagal syncope, heart disease, any systolic pressure reading in the emergency department < 90 or > 180 mm Hg, troponin level above 99th percentile for the normal population, abnormal QRS axis (< -30° or > 100°), QRS duration longer than 130 ms, QTc interval longer than 480 ms, emergency department diagnosis of cardiac syncope and emergency department diagnosis of vasovagal syncope (C statistic 0.88, 95% confidence interval [CI] 0.85-0.90; optimism 0.015; goodness-of-fit p = 0.11). The risk of a serious adverse event within 30 days ranged from 0.4% for a score of -3 to 83.6% for a score of 11. The sensitivity was 99.2% (95% CI 95.9%-100%) for a threshold score of -2 or higher and 97.7% (95% CI 93.5%-99.5%) for a threshold score of -1 or higher.

INTERPRETATION

The Canadian Syncope Risk Score showed good discrimination and calibration for 30-day risk of serious adverse events after disposition from the emergency department. Once validated, the tool will be able to accurately stratify the risk of serious adverse events among patients presenting with syncope, including those at low risk who can be discharged home quickly.