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

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

Prevalence of Intracranial Injury in Adult Patients With Blunt Head Trauma With and Without Anticoagulant or Antiplatelet Use.

STUDY OBJECTIVE: We determine the prevalence of significant intracranial injury among adults with blunt head trauma who are receiving preinjury anticoagulant or antiplatelet medications. METHODS: This was a multicenter, prospective, observational study conducted from December 2007 to December 2015. Patients were enrolled in 3 emergency departments (EDs) in the United States. Adults with blunt head trauma who underwent neuroimaging in the ED were included. Use of preinjury aspirin, clopidogrel, and warfarin was recorded. Data on direct oral anticoagulants were not specifically recorded. The primary outcome was prevalence of significant intracranial injury on neuroimaging. The secondary outcome was receipt of neurosurgical intervention. RESULTS: Among 9,070 patients enrolled in this study, the median age was 53.8 years (interquartile range 34.7 to 74.3 years) and 60.7% were men. A total of 1,323 patients (14.6%) were receiving antiplatelet medications or warfarin, including 635 receiving aspirin alone, 109 clopidogrel alone, and 406 warfarin alone. Compared with that of patients without any coagulopathy, the relative risk of significant intracranial injury was 1.29 (95% confidence interval [CI] 0.88 to 1.87) for patients receiving aspirin alone, 0.75 (95% CI 0.24 to 2.30) for those receiving clopidogrel alone, and 1.88 (95% CI 1.28 to 2.75) for those receiving warfarin alone. The relative risk of significant intracranial injury was 2.88 (95% CI 1.53 to 5.42) for patients receiving aspirin and clopidogrel in combination. CONCLUSION: Patients receiving preinjury warfarin or a combination of aspirin and clopidogrel were at increased risk for significant intracranial injury, but not those receiving aspirin alone. Clinicians should have a low threshold for neuroimaging when evaluating patients receiving warfarin or a combination of aspirin and clopidogrel.

Risk Stratification of Older Adults Who Present to the Emergency Department With Syncope: The FAINT Score.

STUDY OBJECTIVE: Older adults with syncope are commonly treated in the emergency department (ED). We seek to derive a novel risk-stratification tool to predict 30-day serious cardiac outcomes. METHODS: We performed a prospective, observational study of older adults (≥60 years) with unexplained syncope or near syncope who presented to 11 EDs in the United States. Patients with a serious diagnosis identified in the ED were excluded. We collected clinical and laboratory data on all patients. Our primary outcome was 30-day all-cause mortality or serious cardiac outcome. RESULTS: We enrolled 3,177 older adults with unexplained syncope or near syncope between April 2013 and September 2016. Mean age was 73 years (SD 9.0 years). The incidence of the primary outcome was 5.7% (95% confidence interval [CI] 4.9% to 6.5%). Using Bayesian logistic regression, we derived the FAINT score: history of heart failure, history of cardiac arrhythmia, initial abnormal ECG result, elevated pro B-type natriuretic peptide, and elevated high-sensitivity troponin T. A FAINT score of 0 versus greater than or equal to 1 had sensitivity of 96.7% (95% CI 92.9% to 98.8%) and specificity 22.2% (95% CI 20.7% to 23.8%), respectively. The FAINT score tended to be more accurate than unstructured physician judgment: area under the curve 0.704 (95% CI 0.669 to 0.739) versus 0.630 (95% CI 0.589 to 0.670). CONCLUSION: Among older adults with syncope or near syncope of potential cardiac cause, a FAINT score of zero had a reasonably high sensitivity for excluding death and serious cardiac outcomes at 30 days. If externally validated, this tool could improve resource use for this common condition.

The Effect of Shared Decisionmaking on Patients' Likelihood of Filing a Complaint or Lawsuit: A Simulation Study.

STUDY OBJECTIVE: Shared decisionmaking has been promoted as a method to increase the patient-centeredness of medical decisionmaking and decrease low-yield testing, but little is known about its medicolegal ramifications in the setting of an adverse outcome. We seek to determine whether the use of shared decisionmaking changes perceptions of fault and liability in the case of an adverse outcome. METHODS: This was a randomized controlled simulation experiment conducted by survey, using clinical vignettes featuring no shared decisionmaking, brief shared decisionmaking, or thorough shared decisionmaking. Participants were adult US citizens recruited through an online crowd-sourcing platform. Participants were randomized to vignettes portraying 1 of 3 levels of shared decisionmaking. All other information given was identical, including the final clinical decision and the adverse outcome. The primary outcome was reported likelihood of pursuing legal action. Secondary outcomes included perceptions of fault, quality of care, and trust in physician. RESULTS: We recruited 804 participants. Participants exposed to shared decisionmaking (brief and thorough) were 80% less likely to report a plan to contact a lawyer than those not exposed to shared decisionmaking (12% and 11% versus 41%; odds ratio 0.2; 95% confidence interval 0.12 to 0.31). Participants exposed to either level of shared decisionmaking reported higher trust, rated their physicians more highly, and were less likely to fault their physicians for the adverse outcome compared with those exposed to the no shared decisionmaking vignette. CONCLUSION: In the setting of an adverse outcome from a missed diagnosis, use of shared decisionmaking may affect patients' perceptions of fault and liability.

Clinical Benefit of Hospitalization for Older Adults With Unexplained Syncope: A Propensity-Matched Analysis.

STUDY OBJECTIVE: Many adults with syncope are hospitalized solely for observation and testing. We seek to determine whether hospitalization versus outpatient management for older adults with unexplained syncope is associated with a reduction in postdisposition serious adverse events at 30 days. METHODS: We performed a propensity score analysis using data from a prospective, observational study of older adults with unexplained syncope or near syncope who presented to 11 emergency departments (EDs) in the United States. We enrolled adults (≥60 years) who presented with syncope or near syncope. We excluded patients with a serious diagnosis identified in the ED. Clinical and laboratory data were collected on all patients. The primary outcome was rate of post-ED serious adverse events at 30 days. RESULTS: We enrolled 2,492 older adults with syncope and no serious ED diagnosis from April 2013 to September 2016. Mean age was 73 years (SD 8.9 years), and 51% were women. The incidence of serious adverse events within 30 days after the index visit was 7.4% for hospitalized patients and 3.19% for discharged patients, representing an unadjusted difference of 4.2% (95% confidence interval 2.38% to 6.02%). After propensity score matching on risk of hospitalization, there was no statistically significant difference in serious adverse events at 30 days between the hospitalized group (4.89%) and the discharged group (2.82%) (risk difference 2.07%; 95% confidence interval -0.24% to 4.38%). CONCLUSION: In our propensity-matched sample of older adults with unexplained syncope, for those with clinical characteristics similar to that of the discharged cohort, hospitalization was not associated with improvement in 30-day serious adverse event rates.

Shared Decisionmaking in the Emergency Department: A Guiding Framework for Clinicians.

Shared decisionmaking has been proposed as a method to promote active engagement of patients in emergency care decisions. Despite the recent attention shared decisionmaking has received in the emergency medicine community, including being the topic of the 2016 Academic Emergency Medicine Consensus Conference, misconceptions remain in regard to the precise meaning of the term, the process, and the conditions under which it is most likely to be valuable. With the help of a patient representative and an interaction designer, we developed a simple framework to illustrate how shared decisionmaking should be approached in clinical practice. We believe it should be the preferred or default approach to decisionmaking, except in clinical situations in which 3 factors interfere. These 3 factors are lack of clinical uncertainty or equipoise, patient decisionmaking ability, and time, all of which can render shared decisionmaking infeasible. Clinical equipoise refers to scenarios in which there are 2 or more medically reasonable management options. Patient decisionmaking ability refers to a patient's capacity and willingness to participate in his or her emergency care decisions. Time refers to the acuity of the clinical situation (which may require immediate action) and the time that the clinician has to devote to the shared decisionmaking conversation. In scenarios in which there is only one medically reasonable management option, informed consent is indicated, with compassionate persuasion used as appropriate. If time or patient capacity is lacking, physician-directed decisionmaking will occur. With this framework as the foundation, we discuss the process of shared decisionmaking and how it can be used in practice. Finally, we highlight 5 common misconceptions in regard to shared decisionmaking in the ED. With an improved understanding of shared decisionmaking, this approach should be used to facilitate the provision of high-quality, patient-centered emergency care.

Sensitivity of plain radiography for pediatric cervical spine injury.

Pediatric patients with suspected cervical spine injuries (CSI) often receive a computed tomography (CT) scan as an initial diagnostic imaging test. While sensitive, CT of the cervical spine carries significant radiation and risk of lethal malignant transformation later in life. Plain radiographs carry significantly less radiation and could serve as the preferred screening tool, provided they have a high functional sensitivity in detecting pediatric patients with CSI. We hypothesize that plain cervical spine radiographs can reliably detect pediatric patients with CSI and seek to quantify the functional sensitivity of plain radiography as compared to CT. We analyzed data from the NEXUS cervical spine study to assess the sensitivity of plain radiographs in the evaluation of CSI. We identified all pediatric patients who underwent plain radiographic imaging, and all pediatric patients found to have CSI. We then determined the sensitivity of plain radiographs in detecting pediatric patients with CSI. We identified 44 pediatric patients with CSI in the dataset with age ranging from 2 to 18 years old. Thirty-two of the 44 pediatric patients received cervical spine plain films as a part of their workup. Plain films were able to identify all 32 pediatric patients with CSI to yield a sensitivity of 100 % in detecting injury victims (95 % confidence interval 89.1-100.0 %). Plain radiography was highly sensitive for the identification of CSI in our cohort of pediatric patients and is useful as a screening tool in the evaluation of pediatric CSI.

National trends in resource utilization associated with ED visits for syncope.

BACKGROUND: Over the last 20 years, numerous research articles and clinical guidelines aimed at optimizing resource utilization for emergency department (ED) patients presenting with syncope have been published. HYPOTHESIS: We hypothesized that there would be temporal trends in syncope-related ED visits and associated trends in imaging, hospital admissions, and diagnostic frequencies. METHODS: The ED component of National Hospital Ambulatory Medical Care Survey was analyzed from 2001 through 2010, comprising more than 358000 visits (representing an estimated 1.18 billion visits nationally). We selected ED visits with a reason for visit of syncope or fainting and calculated nationally representative weighted estimates for prevalence of such visits and associated rates of advanced imaging utilization and admission. For admitted patients from 2005 to 2010, the most frequent hospital discharge diagnoses were tabulated. RESULTS: During the study period, there were more than 3500 actual ED visits (representing 11.9 million visits nationally) related to syncope, representing roughly 1% of all ED visits. Admission rates for syncope patients ranged from 27% to 35% and showed no significant downward trend (P = .1). Advanced imaging rates increased from about 21% to 45% and showed a significant upward trend (P < .001). For admitted patients, the most common hospital discharge diagnosis was the symptomatic diagnosis of "syncope and collapse" (36.4%). CONCLUSIONS: Despite substantial efforts by medical researchers and professional societies, resource utilization associated with ED visits for syncope appears to have actually increased. There have been no apparent improvements in diagnostic yield for admissions. Novel strategies may be needed to change practice patterns for such patients.

Emergency Physicians' Perceptions and Decision-making Processes Regarding Patients Presenting with Palpitations.

BACKGROUND: Palpitations are a common emergency department (ED) complaint, yet relatively little research exists on this topic from an emergency care perspective. OBJECTIVES: We sought to describe the perceptions and clinical decision-making processes of emergency physicians (EP) surrounding patients with palpitations. METHODS: We conducted 21 semistructured interviews with a convenience sample of EPs. We recruited participants from academic and community practice settings from four regions of the United States. The transcribed interviews were analyzed using a combination of structural coding and grounded theory approaches with ATLAS.ti, a qualitative data analysis software program (version 7; Atlas.ti Scientific Software Development GmbH, Berlin, Germany). RESULTS: EPs perceive palpitations to be a common but generally benign chief complaint. EPs' clinical approach to palpitations, with regards to testing, treatment, and ED management, can be classified as relating to one or more of the following themes: (1) risk stratification, (2) diagnostic categorization, (3) algorithmic management, and (4) case-specific gestalt. With regard to disposition decisions, four main themes emerged: (1) presence of a serious diagnosis, (2) perceived need for further cardiac testing/monitoring, (3) presence of key associated symptoms, (4) request of other physician or patient desire. The interrater reliability exercise yielded a Fleiss' kappa measure of 0.69, indicating substantial agreement between coders. CONCLUSION: EPs perceive palpitations to be a common but generally benign chief complaint. EPs rely on one or more of four main clinical approaches to manage these patients. These findings could help guide future efforts at developing risk-stratification tools and clinical algorithms for patients with palpitations.

A conceptual model of emergency physician decision making for head computed tomography in mild head injury.

The use of computed tomographic scanning in blunt head trauma has increased dramatically in recent years without an accompanying rise in the prevalence of injury or hospital admission for serious conditions. Because computed tomography is neither harmless nor inexpensive, researchers have attempted to optimize utilization, largely through research that describes which clinical variables predict intracranial injury, and use this information to develop clinical decision instruments. Although such techniques may be useful when the benefits and harms of each strategy (neuroimaging vs observation) are quantifiable and amenable to comparison, the exact magnitude of these benefits and harms remains unknown in this clinical scenario. We believe that most clinical decision instrument development efforts are misguided insofar as they ignore critical, nonclinical factors influencing the decision to image. In this article, we propose a conceptual model to illustrate how clinical and nonclinical factors influence emergency physicians making this decision. We posit that elements unrelated to standard clinical factors, such as personality of the physician, fear of litigation and of missed diagnoses, patient expectations, and compensation method, may have equal or greater impact on actual decision making than traditional clinical factors. We believe that 3 particular factors deserve special consideration for further research: fear of error/malpractice, financial incentives, and patient engagement. Acknowledgement and study of these factors will be essential if we are to understand how emergency physicians truly make these decisions and how test-ordering behavior can be modified.

The association between advanced diagnostic imaging and ED length of stay.

OBJECTIVE: There has been a rise in advanced diagnostic imaging (ADI) use in the emergency department (ED). Increased utilization may contribute to longer length of stay (LOS), but prior reports have not considered improved methods for modeling skewed LOS data. METHODS: The 2010 National Hospital Ambulatory Medical Care Survey data were analyzed by 5 common ED chief complaints. Generalized linear model (GLM) was compared to quantile and ordinary least squares (OLS) regression to evaluate the association between ADI and ED LOS. Receipt of computed tomography or magnetic resonance imaging was the primary exposure. Emergency department LOS was the primary outcome. RESULTS: Of the 33,685 ED visits analyzed, 17% involved ADI. The median LOS for patients without ADI was 138 minutes compared to 252 minutes for those who received ADI. Overall, GLM offered the most unbiased estimates, although it provided similar adjusted point estimates to OLS for the marginal change in LOS associated with ADI. The effect of imaging differed by LOS quantile, especially for patients with abdominal pain, fever, and back symptoms. CONCLUSIONS: Generalized linear model offered an improved modeling approach compared to OLS and quantile regression. Consideration of such techniques may facilitate a more complete view of the effect of ADI on ED LOS.

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.

External Validation of the Recalibrated HEART Score for Evaluation of Possible Acute Coronary Syndrome.

A single high-sensitivity troponin-T (hs-TnT) measurement may be sufficient to risk-stratify emergency department (ED) patients with possible acute coronary syndrome (ACS) using the recalibrated History, Electrocardiogram, Age, Risk Factors, Troponin (rHEART) score. We sought to validate this approach in a multiethnic population of United States patients and investigate gender-specific differences in performance. We conducted a secondary analysis of a prospective cohort study of adult ED patients with possible ACS at a single, urban, academic hospital. We investigated the diagnostic performance of rHEART for the incidence of type-1 acute myocardial infarction (AMI) and other major adverse cardiac events (MACE) at 30 days, using both single (19 ng/L) and gender-specific (14 ng/L for women, 22 ng/L for men) 99th percentile hs-TnT thresholds. The 821 patients included were 54% women, 57% Hispanic, and 26% Black. Overall, 4.6% of patients had MACE, including 2.4% with AMI. Single-threshold rHEART ≤3 had a sensitivity of 94.4% (95% confidence interval 81% to 99%) and negative predictive values of 99.3% (98% to 100%) for MACE; gender-specific thresholds performed nearly identically. Sensitivity and negative predictive values for AMI were 90.0% (67% to 98%) and 99.3% (97% to 100%). Excluding patients presenting <3 hours from symptom onset improved sensitivity for MACE and AMI to 97.0% (84% to 100%) and 94.1% (71% to 100%). Logistic regression demonstrated odds of MACE increased with higher rHEART scores at a similar rate for men and women. In conclusion, a single initial hs-TnT and rHEART score can be used to risk-stratify male and female ED patients with possible ACS, especially when drawn >3 hours after symptom onset.

Flexible-Interval High-Sensitivity Troponin Velocity for the Detection of Acute Coronary Syndromes.

Many algorithms for emergency department (ED) evaluation of acute coronary syndrome (ACS) using high-sensitivity troponin assays rely on the detection of a "delta," the difference in concentration over a predetermined interval, but collecting specimens at specific times can be difficult in the ED. We evaluate the use of troponin "velocity," the rate of change of troponin concentration over a flexible short interval for the prediction of major adverse cardiac events (MACEs) at 30 days. We conducted a prospective, observational study on a convenience sample of 821 patients who underwent ACS evaluation at a high-volume, urban ED. We determined the diagnostic performance of a novel velocity-based algorithm and compared the performance of 1- and 2-hour algorithms adapted from the European Society of Cardiology (ESC) using delta versus velocity. A total of 7 of 332 patients (2.1%) classified as low risk by the velocity-based algorithm experienced a MACE by 30 days compared with 35 of 221 (13.8%) of patients classified as greater than low risk, yielding a sensitivity of 83.3% (95% confidence interval [CI] 68.6% to 93.0%) and negative predictive value (NPV) of 97.9% (95% CI 95.9% to 98.9%). The ESC-derived algorithms using delta or velocity had NPVs ranging from 98.4% (95% CI 96.4% to 99.3%) to 99.6% (95% CI 97.0% to 99.9%) for 30-day MACEs. The NPV of the novel velocity-based algorithm for MACE at 30 days was borderline, but the substitution of troponin velocity for delta in the framework of the ESC algorithms performed well. In conclusion, specimen collection within strict time intervals may not be necessary for rapid evaluation of ACS with high-sensitivity troponin.

Clinicians' perspectives on the implementation of patient decision aids in the emergency department: A qualitative interview study.

OBJECTIVE: Decision aids (DAs) are tools to facilitate and standardize shared decision making (SDM). Although most emergency clinicians (ECs) perceive SDM appropriate for emergency care, there is limited uptake of DAs in clinical practice. The objective of this study was to explore barriers and facilitators identified by ECs regarding the implementation of DAs in the emergency department (ED). METHODS: We conducted a qualitative interview study guided by implementation science frameworks. ECs participated in interviews focused on the implementation of DAs for the disposition of patients with low-risk chest pain and unexplained syncope in the ED. Interviews were recorded and transcribed verbatim. We then iteratively developed a codebook with directed qualitative content analysis. RESULTS: We approached 25 ECs working in urban New York, of whom 20 agreed to be interviewed (mean age, 41 years; 25% women). The following 6 main barriers were identified: (1) poor DA accessibility, (2) concern for increased medicolegal risk, (3) lack of perceived need for a DA, (4) patient factors including lack of capacity and limited health literacy, (5) skepticism about validity of DAs, and (6) lack of time to use DAs. The 6 main facilitators identified were (1) positive attitudes toward SDM, (2) patient access to follow-up care, (3) potential for improved patient satisfaction, (4) potential for improved risk communication, (5) strategic integration of DAs into the clinical workflow, and (6) institutional support of DAs. CONCLUSIONS: ECs identified multiple barriers and facilitators to the implementation of DAs into clinical practice. These findings could guide implementation efforts targeting the uptake of DA use in the ED.

Evaluation of emergency department visits for mental health complaints during the COVID-19 pandemic.

Background: The COVID-19 pandemic has resulted in over 6 million deaths worldwide as of March 2022. Adverse psychological effects on patients and the general public linked to the pandemic have been well documented. Methods: We conducted a retrospective analysis of adult emergency department (ED) encounters with diagnoses of anxiety, depression, and suicidal ideation using International Classification of Diseases, Tenth Revision (ICD-10) codes at a tertiary care hospital in New York City from March 15 through July 31, 2020 and compared it with ED encounters during the same time period in the previous 3 years (2017-2019). The relative risk (RR) of these diagnoses was calculated comparing a prepandemic sample to a pandemic sample, accounting for total volume of ED visits. Results: A total of 2816 patient encounters met the inclusion criteria. The study period in 2020 had 31.5% lower overall ED volume seen during the same time period in the previous 3 years (27,874 vs average 40,716 ED encounters). The risk of presenting with anxiety during the study period in 2020 compared to prior 3 years was 1.40 (95% confidence interval [CI] 1.21-1.63), for depression was 1.47 (95% CI 1.28-1.69), and for suicidal ideation was 1.05 (95% CI 0.90-1.23). There was an increase in admissions for depression during the pandemic period (15.2% increase, 95% CI 4.6%-25.7%). Conclusion: There was a relative increase in patients presenting to the ED with complaints of anxiety and depression during the height of the COVID-19 pandemic, while absolute numbers remained stable. Our results highlight the importance of acute care-based mental health resources and interventions to support patients during this pandemic.

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.