Cardiac Magnetic Resonance Imaging Versus Invasive-Based Strategies in Patients With Chest Pain and Detectable to Mildly Elevated Serum Troponin: A Randomized Clinical Trial.

BACKGROUND: The optimal diagnostic strategy for patients with chest pain and detectable to mildly elevated serum troponin is not known. The objective was to compare clinical outcomes among an early decision for a noninvasive versus an invasive-based care pathway. METHODS: The CMR-IMPACT trial (Cardiac Magnetic Resonance Imaging Strategy for the Management of Patients with Acute Chest Pain and Detectable to Elevated Troponin) was conducted at 4 United States tertiary care hospitals from September 2013 to July 2018. A convenience sample of 312 participants with acute chest pain symptoms and a contemporary troponin between detectable and 1.0 ng/mL were randomized early in their care to 1 of 2 care pathways: invasive-based (n=156) or cardiac magnetic resonance (CMR)-based (n=156) with modification allowed as the patient condition evolved. The primary outcome was a composite including death, myocardial infarction, and cardiac-related hospital readmission or emergency visits. RESULTS: Participants (N=312, mean age, 60.6 years, SD 11.3; 125 women [59.9%]), were followed over a median of 2.6 years (95% CI, 2.4-2.9). Early assigned testing was initiated in 102 out of 156 (65.3%) CMR-based and 110 out of 156 (70.5%) invasive-based participants. The primary outcome (CMR-based versus invasive-based) occurred in 59% versus 52% (hazard ratio, 1.17 [95% CI, 0.86-1.57]), acute coronary syndrome after discharge 23% versus 22% (hazard ratio, 1.07 [95% CI, 0.67-1.71]), and invasive angiography at any time 52% versus 74% (hazard ratio, 0.66 [95% CI, 0.49-0.87]). Among patients completing CMR imaging, 55 out of 95 (58%) were safely identified for discharge based on a negative CMR and did not have angiography or revascularization within 90 days. Therapeutic yield of angiography was higher in the CMR-based arm (52 interventions in 81 angiographies [64.2%] versus 46 interventions in 115 angiographies [40.0%] in the invasive-based arm [P=0.001]). CONCLUSIONS: Initial management with CMR or invasive-based care pathways resulted in no detectable difference in clinical and safety event rates. The CMR-based pathway facilitated safe discharge, enriched the therapeutic yield of angiography, and reduced invasive angiography utilization over long-term follow-up. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT01931852.

Finding acute coronary syndrome with serial troponin testing for rapid assessment of cardiac ischemic symptoms (FAST-TRAC): a study protocol.

OBJECTIVE: To determine the utility of a highly sensitive troponin assay when utilized in the emergency department. METHODS: The FAST-TRAC study prospectively enrolled >1,500 emergency department patients with suspected acute coronary syndrome within 6 hours of symptom onset and 2 hours of emergency department presentation. It has several unique features that are not found in the majority of studies evaluating troponin. These include a very early presenting population in whom prospective data collection of risk score parameters and the physician's clinical impression of the probability of acute coronary syndrome before any troponin data were available. Furthermore, two gold standard diagnostic definitions were determined by a pair of cardiologists reviewing two separate data sets; one that included all local troponin testing results and a second that excluded troponin testing so that diagnosis was based solely on clinical grounds. By this method, a statistically valid head-to-head comparison of contemporary and high sensitivity troponin testing is obtainable. Finally, because of a significant delay in sample processing, a unique ability to define the molecular stability of various troponin assays is possible. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT00880802.

Troponin is unrelated to outcomes in heart failure patients discharged from the emergency department.

Background: Prior data has demonstrated increased mortality in hospitalized patients with acute heart failure (AHF) and troponin elevation. No data has specifically examined the prognostic significance of troponin elevation in patients with AHF discharged after emergency department (ED) management. Objective: Evaluate the relationship between troponin elevation and outcomes in patients with AHF who are treated and released from the ED. Methods: This was a secondary analysis of the Get with the Guidelines to Reduce Disparities in AHF Patients Discharged from the ED (GUIDED-HF) trial, a randomized, controlled trial of ED patients with AHF who were discharged. Patients with elevated conventional troponin not due to acute coronary syndrome (ACS) were included. Our primary outcome was a composite endpoint: time to 30-day cardiovascular death and/or heart failure-related events. Results: Of the 491 subjects included in the GUIDED-HF trial, 418 had troponin measured during the ED evaluation and 66 (16%) had troponin values above the 99th percentile. Median age was 63 years (interquartile range, 54-70), 62% (n = 261) were male, 63% (n = 265) were Black, and 16% (n = 67) experienced our primary outcome. There were no differences in our primary outcome between those with and without troponin elevation (12/66, 18.1% vs 55/352, 15.6%; P = 0.60). This effect was maintained regardless of assignment to usual care or the intervention arm. In multivariable regression analysis, there was no association between our primary outcome and elevated troponin (hazard ratio, 1.00; 95% confidence interval,  0.49-2.01, P = 0.994). Conclusion: If confirmed in a larger cohort, these findings may facilitate safe ED discharge for a group of patients with AHF without ACS when an elevated troponin is the primary reason for admission.

Assessing the safety of interrogating cardiac-implantable electronic devices with brand-mismatched remote interrogators: a pilot study.

OBJECTIVE: Remote cardiac implantable electronic device (CIED) interrogators, originally developed for home use, have been proven to be efficacious in clinical settings, especially emergency departments. Concern exists that attempting to interrogate a CIED with the remote interrogator of a different brand, i.e., a brand-mismatched interrogator, may cause device malfunction. The aim of this study was to determine if intentionally attempting to interrogate a CIED with a brand-mismatched remote interrogator resulted in device malfunction. METHODS: A total of 75 ex vivo CIEDs manufactured by various companies underwent attempted interrogation by a brand-mismatched remote interrogator. CIED settings were compared before and after attempted mismatch interrogation. A total of 30 in vivo CIEDs were then randomized for an attempted 2-minute mismatched remote interrogation by one of the two possible mismatched remote interrogators. CIED settings were compared before and after attempted mismatch interrogation. RESULTS: Of 150 ex vivo brand-mismatched interrogations, no device setting changes or malfunctions occurred; no remote interrogators connected to a mismatched CIED, and no devices were turned off. In the 30 patients undergoing brand-mismatched interrogations, the mean (standard deviation) age was 71.6 ( ± 14.7) years, 16 (53%) were male, with 24 pacemakers (80%), four pacemaker/implantable cardioverter defibrillators (13%), and two implantable cardioverter defibrillators (7%). Of the 30 mismatched interrogations performed, no device setting changes or malfunctions occurred; no remote interrogators connected to a mismatched CIED, and no devices turned off. CONCLUSION: In a total 180 attempted brand-mismatched CIED interrogations, no CIED malfunctions occurred. This suggests that the use of remote CIED interrogators when device manufacturer is unknown is unlikely to result in adverse CIED-related events.

The Impact of Accelerated Diagnostic Protocol Implementation on Chest Pain Observation Unit Utilization.

BACKGROUND: Data evaluating the impact of the history, ECG, age, risk factors, and troponin (HEART) Pathway on observation unit (OU) use is limited. The objective of this study is to determine how HEART Pathway implementation affects OU use. METHODS: An analysis of OU registry data from October 2012 to October 2016, 2 years before and after HEART Pathway implementation at an academic medical center, was conducted. Adult patients placed in the OU for chest pain were included. The proportion of patients placed in the OU chest pain protocol per total OU volume and hospitalization and myocardial infarction (MI) rates were determined. Proportions before versus after implementation were compared using χ2 tests and age was compared using a Mann-Whitney U test. RESULTS: During the study period, 1688 patients with chest pain before HEART Pathway implementation and 1692 after were included. The proportion of chest pain patients in the OU per total OU volume decreased following implementation from (57% [1688/2968] to 43.6% [1692/3882]; P < 0.001). Before HEART Pathway implementation, the hospitalization rate was 10.4% (175/1688) versus 12.4% (210/1692) after (P = 0.07). More patients were diagnosed with MI following implementation (0.8% [14/1665] vs. 2.0% [33/1686]; P = 0. 008). Median age was older postimplementation (52 years [IQR: 45-59 years] vs. 54 years [IQR: 48-64 years]; P < 0. 001). CONCLUSIONS: HEART Pathway implementation resulted in management of higher risk patients in the OU. Following implementation, OU chest pain patients were older and were more likely to be hospitalized or diagnosed with MI.

Prehospital time for patients with acute cardiac complaints: A rural health disparity.

OBJECTIVE: Delays in care for patients with acute cardiac complaints are associated with increased morbidity and mortality. The objective of this study was to quantify rural and urban differences in prehospital time intervals for patients with cardiac complaints. METHODS: The ESO Data Collaborative dataset consisting of records from 1332 EMS agencies was queried for 9-1-1 encounters with acute cardiac problems among adults (age ≥ 18) from 1/1/2013-6/1/2018. Location was classified as rural or urban using the 2010 United States Census. The primary outcome was total prehospital time. Generalized estimating equations evaluated differences in the average times between rural and urban encounters while controlling for age, sex, race, transport mode, loaded mileage, and patient stability. RESULTS: Among 428,054 encounters, the median age was 62 (IQR 50-75) years with 50.7% female, 75.3% white, and 10.3% rural. The median total prehospital, response, scene, and transport times were 37.0 (IQR 29.0-48.0), 6.0 (IQR 4.0-9.0), 16.0 (IQR 12.0-21.0), and 13.0 (IQR 8.0-21.0) minutes. Rural patients had an average total prehospital time that was 16.76 min (95%CI 15.15-18.38) longer than urban patients. After adjusting for covariates, average total time was 5.08 (95%CI 4.37-5.78) minutes longer for rural patients. Average response and transport time were 4.36 (95%CI 3.83-4.89) and 0.62 (95%CI 0.33-0.90) minutes longer for rural patients. Scene time was similar in rural and urban patients (0.09 min, 95%CI -0.15-0.33). CONCLUSION: Rural patients with acute cardiac complaints experienced longer prehospital time than urban patients, even after accounting for other key variables, such as loaded mileage.

Monocyte chemoattractant protein-1 is not predictive of cardiac events in patients with non-low-risk chest pain.

BACKGROUND: Prior studies suggest monocyte chemoattractant protein-1 (MCP-1) may be useful for risk stratifying ED patients with chest pain. We hypothesise that MCP-1 will be predictive of 90-day major adverse cardiovascular events (MACEs) in non-low-risk patients. METHODS: A case-control study was nested within a prospective multicentre cohort (STOP-CP), which enrolled adult patients being evaluated for acute coronary syndrome at eight US EDs from 25 January 2017 to 06 September 2018. Patients with a History, ECG, Age, and Risk factor score (HEAR score) ≥4 or coronary artery disease (CAD), a non-ischaemic ECG, and non-elevated contemporary troponins at 0 and 3 hours were included. Cases were patients with 90-day MACE (all-cause death, myocardial infarction or revascularisation). Controls were patients without MACE selected with frequency matching using age, sex, race, and HEAR score or the presence of CAD. Serum MCP-1 was measured. Sensitivity and specificity were determined for cut-off points of 194 pg/mL, 200 pg/mL, 238 pg/mL and 281 pg/mL. Logistic regression adjusting for age, sex, race, and HEAR score/presence of CAD was used to determine the association between MCP-1 and 90-day MACE. A separate logistic model also included high-sensitivity troponin (hs-cTnT). RESULTS: Among 40 cases and 179 controls, there was no difference in age (p=0.90), sex (p=1.00), race (p=0.85), or HEAR score/presence of CAD (p=0.89). MCP-1 was similar in cases (median 191.9 pg/mL, IQR: 161.8-260.1) and controls (median 196.6 pg/mL, IQR: 163.0-261.1) (p=0.48). At a cut-off point of 194 pg/mL, MCP-1 was 50.0% (95% CI 33.8% to 66.2%) sensitive and 46.9% (95% CI 39.4% to 54.5%) specific for 90-day MACE. After adjusting for covariates, MCP-1 was not associated with 90-day MACE at any cut-off point (at 194 pg/mL, OR 0.88 (95% CI 0.43 to 1.79)). When including hs-cTnT in the model, MCP-1 was not associated with 90-day MACE at any cut-off point (at 194 pg/mL, OR 0.85 (95% CI 0.42 to 1.73)). CONCLUSION: MCP-1 is not predictive of 90-day MACE in patients with non-low-risk chest pain.

Healthcare Use After Buprenorphine Prescription in a Community Emergency Department: A Cohort Study.

INTRODUCTION: Recent studies from urban academic centers have shown the promise of emergency physician-initiated buprenorphine for improving outcomes in opioid use disorder (OUD) patients. We investigated whether emergency physician-initiated buprenorphine in a rural, community setting decreases subsequent healthcare utilization for OUD patients. METHODS: We performed a retrospective chart review of patients presenting to a community hospital emergency department (ED) who received a prescription for buprenorphine from June 15, 2018-June 15, 2019. Demographic and opioid-related International Classification of Diseases, 10th Revision, (ICD-10) codes were documented and used to create a case-matched control cohort of demographically matched patients who presented in a similar time frame with similar ICD-10 codes but did not receive buprenorphine. We recorded 12-month rates of ED visits, all-cause hospitalizations, and opioid overdoses. Differences in event occurrences between groups were assessed with Poisson regression. RESULTS: Overall 117 patients were included in the study: 59 who received buprenorphine vs 58 controls. The groups were well matched, both roughly 90% White and 60% male, with an average age of 33.4 years for both groups. Controls had a median two ED visits (range 0-33), median 0.5 hospitalizations (range 0-8), and 0 overdoses (range 0-3), vs median one ED visit (range 0-8), median 0 hospitalizations (range 0-4), and median 0 overdoses (range 0-3) in the treatment group. The incidence rate ratio (IRR) for counts of ED visits was 0.61, 95% confidence interval (CI), 0.49, 0.75, favoring medication-assisted treatment (MAT). For hospitalizations, IRR was 0.34, 95% CI, 0.22, 0.52 favoring MAT, and for overdoses was 1.04, 95% CI, 0.53, 2.07. CONCLUSION: Initiation of buprenorphine by ED providers was associated with lower 12-month ED visit and all-cause hospitalization rates with comparable overdose rates compared to controls. These findings show the ED's potential as an initiation point for medication-assisted treatment in OUD patients.

Improvement in Kansas City Cardiomyopathy Questionnaire Scores After a Self-Care Intervention in Patients With Acute Heart Failure Discharged From the Emergency Department.

BACKGROUND: We conducted a secondary analysis of changes in the Kansas City Cardiomyopathy Questionnaire (KCCQ)-12 over 30 days in a randomized trial of self-care coaching versus structured usual care in patients with acute heart failure who were discharged from the emergency department. METHODS: Patients in 15 emergency departments completed the KCCQ-12 at emergency department discharge and at 30 days. We compared change in KCCQ-12 scores between the intervention and usual care arms, adjusted for enrollment KCCQ-12 and demographic characteristics. We used linear regression to describe changes in KCCQ-12 summary scores and logistic regression to characterize clinically meaningful KCCQ-12 subdomain changes at 30 days. RESULTS: There were 350 patients with both enrollment and 30-day KCCQ summary scores available; 166 allocated to usual care and 184 to the intervention arm. Median age was 64 years (interquartile range, 55-70), 37% were female participants, 63% were Black, median KCCQ-12 summary score at enrollment was 47 (interquartile range, 33-64). Self-care coaching resulted in significantly greater improvement in health status compared with structured usual care (5.4-point greater improvement, 95% CI, 1.12-9.68; P=0.01). Improvements in health status in the intervention arm were driven by improvements within the symptom frequency (adjusted odds ratio, 1.62 [95% CI, 1.01-2.59]) and quality of life (adjusted odds ratio, 2.39 [95% CI, 1.46-3.90]) subdomains. CONCLUSIONS: In this secondary analysis, patients with acute heart failure who received a tailored, self-care intervention after emergency department discharge had clinically significant improvements in health status at 30 days compared with structured usual care largely due to improvements within the symptom frequency and quality of life subdomains of the KCCQ-12. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02519283.

Implementing a Second-Level Observation Unit at a Large Academic Medical Center.

Supplemental digital content is available in the text.

Effect of a Self-care Intervention on 90-Day Outcomes in Patients With Acute Heart Failure Discharged From the Emergency Department: A Randomized Clinical Trial.

Importance: Up to 20% of patients who present to the emergency department (ED) with acute heart failure (AHF) are discharged without hospitalization. Compared with rates in hospitalized patients, readmission and mortality are worse for ED patients. Objective: To assess the impact of a self-care intervention on 90-day outcomes in patients with AHF who are discharged from the ED. Design, Setting, and Participants: Get With the Guidelines in Emergency Department Patients With Heart Failure was an unblinded, parallel-group, multicenter randomized trial. Patients were randomized 1:1 to usual care vs a tailored self-care intervention. Patients with AHF discharged after ED-based management at 15 geographically diverse EDs were included. The trial was conducted from October 28, 2015, to September 5, 2019. Interventions: Home visit within 7 days of discharge and twice-monthly telephone-based self-care coaching for 3 months. Main Outcomes and Measures: The primary outcome was a global rank of cardiovascular death, HF-related events (unscheduled clinic visit due to HF, ED revisit, or hospitalization), and changes in the Kansas City Cardiomyopathy Questionnaire-12 (KCCQ-12) summary score (SS) at 90 days. Key secondary outcomes included the global rank outcome at 30 days and changes in the KCCQ-12 SS score at 30 and 90 days. Intention-to-treat analysis was performed for the primary, secondary, and safety outcomes. Per-protocol analysis was conducted including patients who completed a home visit and had scheduled outpatient follow-up in the intervention arm. Results: Owing to slow enrollment, 479 of a planned 700 patients were randomized: 235 to the intervention arm and 244 to the usual care arm. The median age was 63.0 years (interquartile range, 54.7-70.2), 302 patients (63%) were African American, 305 patients (64%) were men, and 178 patients (37%) had a previous ejection fraction greater than 50%. There was no significant difference in the primary outcome between patients in the intervention vs usual care arm (hazard ratio [HR], 0.89; 95% CI, 0.73-1.10; P = .28). At day 30, patients in the intervention arm had significantly better global rank (HR, 0.80; 95% CI, 0.64-0.99; P = .04) and a 5.5-point higher KCCQ-12 SS (95% CI, 1.3-9.7; P = .01), while at day 90, the KCCQ-12 SS was 2.7 points higher (95% CI, -1.9 to 7.2; P = .25). Conclusions and Relevance: The self-care intervention did not improve the primary global rank outcome at 90 days in this trial. However, benefit was observed in the global rank and KCCQ-12 SS at 30 days, suggesting that an early benefit of a tailored self-care program initiated at an ED visit for AHF was not sustained through 90 days. Trial Registration: ClinicalTrials.gov Identifier: NCT02519283.

Sex and race differences in safety and effectiveness of the HEART pathway accelerated diagnostic protocol for acute chest pain.

BACKGROUND: The HEART Pathway is an accelerated diagnostic protocol for Emergency Department patients with possible acute coronary syndrome. The objective was to compare the safety and effectiveness of the HEART Pathway among women vs men and whites vs non-whites. METHODS: A subgroup analysis of the HEART Pathway Implementation Study was conducted. Adults with chest pain were accrued from November 2013 to January 2016 from 3 Emergency Departments in North Carolina. The primary outcomes were death and myocardial infarction (MI) and hospitalization rates at 30 days. Logistic regression evaluated for interactions of accelerated diagnostic protocol implementation with sex or race and changes in outcomes within subgroups. RESULTS: A total of 8,474 patients were accrued, of which 53.6% were female and 34.0% were non-white. The HEART Pathway identified 32.6% of females as low-risk vs 28.5% of males (P = 002) and 35.6% of non-whites as low-risk vs 28.0% of whites (P < .0001). Among low-risk patients, death or MI at 30 days occurred in 0.4% of females vs 0.5% of males (P = .70) and 0.5% of non-whites vs 0.3% of whites (P = .69). Hospitalization at 30 days was reduced by 6.6% in females (aOR: 0.74, 95% CI: 0.64-0.85), 5.1% in males (aOR: 0.87, 95% CI: 0.75-1.02), 8.6% in non-whites (aOR: 0.72, 95% CI: 0.60-0.86), and 4.5% in whites (aOR: 0.83, 95% CI: 0.73-0.94). Interactions were not significant. CONCLUSION: Women and non-whites are more likely to be classified as low-risk by the HEART Pathway. HEART Pathway implementation is associated with decreased hospitalizations and a very low death and MI rate among low-risk patients regardless of sex or race.

The disutility of stress testing in low-risk HEART Pathway patients.

BACKGROUND: The HEART Pathway identifies low-risk chest pain patients for discharge from the Emergency Department without stress testing. However, HEART Pathway recommendations are not always followed. The objective of this study is to determine the frequency and diagnostic yield of stress testing among low-risk patients. METHODS: An academic hospital's chest pain registry was analyzed for low-risk HEART Pathway patients (HEAR score ≤ 3 with non-elevated troponins) from 1/2017 to 7/2018. Stress tests were reviewed for inducible ischemia. Diagnostic yield was defined as the rate of obstructive CAD among patients with positive stress testing. T-test or Fisher's exact test was used to test the univariate association of age, sex, race/ethnicity, and HEAR score with stress testing. Multivariate logistic regression was used to determine the association of age, sex, race/ethnicity, and HEAR score with stress testing. RESULTS: There were 4743 HEART Pathway assessments, with 43.7% (2074/4743) being low-risk. Stress testing was performed on 4.1% (84/2074). Of the 84 low-risk patients who underwent testing, 8.3% (7/84) had non-diagnostic studies and 2.6% (2/84) had positive studies. Among the 2 patients with positive studies, angiography revealed that 1 had widely patent coronary arteries and the other had multivessel obstructive coronary artery disease, making the diagnostic yield of stress testing 1.2% (1/84). Each one-point increase in HEAR score (aOR 2.17, 95% CI 1.45-3.24) and being male (aOR 1.59, 95% CI 1.02-2.49) were associated with testing. CONCLUSIONS: Stress testing among low-risk HEART Pathway patients was uncommon, low yield, and more likely in males and those with a higher HEAR score.

HEART Pathway Implementation Safely Reduces Hospitalizations at One Year in Patients With Acute Chest Pain.

STUDY OBJECTIVE: We determine whether implementation of the HEART (History, ECG, Age, Risk Factors, Troponin) Pathway is safe and effective in emergency department (ED) patients with possible acute coronary syndrome through 1 year of follow-up. METHODS: A preplanned analysis of 1-year follow-up data from a prospective pre-post study of 8,474 adult ED patients with possible acute coronary syndrome from 3 US sites was conducted. Patients included were aged 21 years or older, evaluated for possible acute coronary syndrome, and without ST-segment elevation myocardial infarction. Accrual occurred for 12 months before and after HEART Pathway implementation, from November 2013 to January 2016. The HEART Pathway was integrated into the electronic health record at each site as an interactive clinical decision support tool. After integration, ED providers prospectively used the HEART Pathway to identify patients with possible acute coronary syndrome as low risk (appropriate for early discharge without stress testing or angiography) or nonlow risk (appropriate for further inhospital evaluation). Safety (all-cause death and myocardial infarction) and effectiveness (hospitalization) at 1 year were determined from health records, insurance claims, and death index data. RESULTS: Preimplementation and postimplementation cohorts included 3,713 and 4,761 patients, respectively. The HEART Pathway identified 30.7% of patients as low risk; 97.5% of them were free of death and myocardial infarction within 1 year. Hospitalization at 1 year was reduced by 7.0% in the postimplementation versus preimplementation cohort (62.1% versus 69.1%; adjusted odds ratio 0.70; 95% confidence interval 0.63 to 0.78). Rates of death or myocardial infarction at 1 year were similar (11.6% versus 12.4%; adjusted odds ratio 1.00; 95% confidence interval 0.87 to 1.16). CONCLUSION: HEART Pathway implementation was associated with decreased hospitalizations and low adverse event rates among low-risk patients at 1-year follow-up.

Identification of very low-risk acute chest pain patients without troponin testing.

BACKGROUND: The HEART Pathway combines a History ECG Age Risk factor (HEAR) score and serial troponins to risk stratify patients with acute chest pain. However, it is unclear whether patients with HEAR scores of <1 require troponin testing. The objective of this study is to measure the major adverse cardiac event (MACE) rate among patients with <1 HEAR scores and determine whether serial troponin testing is needed to achieve a miss rate <1%. METHODS: A secondary analysis of the HEART Pathway Implementation Study was conducted. HEART Pathway risk assessments (HEAR scores and serial troponin testing at 0 and 3 hours) were completed by the providers on adult patients with chest pain from three US sites between November 2014 and January 2016. MACE (composite of death, myocardial infarction (MI) and coronary revascularisation) at 30 days was determined. The proportion of patients with HEAR scores of <1 diagnosed with MACE within 30 days was calculated. The impact of troponin testing on patients with HEAR scores of <1 was determined using Net Reclassification Improvement Index (NRI). RESULTS: Providers completed HEAR assessments on 4979 patients and HEAR scores<1 occurred in 9.0% (447/4979) of patients. Among these patients, MACE at 30 days occurred in 0.9% (4/447; 95% CI 0.2% to 2.3%) with two deaths, two MIs and 0 revascularisations. The sensitivity and negative predictive value for MACE in the HEAR <1 was 97.8% (95%CI 94.5% to 99.4%) and 99.1% (95% CI 97.7% to 99.8%), respectively, and were not improved by troponin testing. Troponin testing in patients with HEAR <1 correctly reclassified two patients diagnosed with MACE, and was elevated among seven patients without MACE yielding an NRI of 0.9% (95%CI -0.7 to 2.4%). CONCLUSION: These data suggest that patients with HEAR scores of 0 and 1 represent a very low-risk group that may not require troponin testing to achieve a missed MACE rate <1%. Trial registration number NCT02056964.

Comparison of accelerated diagnostic pathways for acute chest pain risk stratification.

BACKGROUND: The History Electrocardiogram Age Risk factor Troponin (HEART) Pathway and Emergency Department Assessment of Chest pain Score (EDACS) are validated accelerated diagnostic pathways designed to risk stratify patients presenting to the emergency department with chest pain. Data from large multisite prospective studies comparing these accelerated diagnostic pathways are limited. METHODS: The HEART Pathway Implementation is a prospective three-site cohort study, which accrued adults with symptoms concerning for acute coronary syndrome. Physicians completed electronic health record HEART Pathway and EDACS risk assessments on participants. Major adverse cardiac events (death, myocardial infarction and coronary revascularisation) at 30 days were determined using electronic health record, insurance claims and death index data. Test characteristics for detection of major adverse cardiac events were calculated for both accelerated diagnostic pathways and McNemar's tests were used for comparisons. RESULTS: 5799 patients presenting to the emergency department were accrued, of which HEART Pathway and EDACS assessments were completed on 4399. Major adverse cardiac events at 30 days occurred in 449/4399 (10.2%). The HEART Pathway identified 38.4% (95% CI 37.0% to 39.9%) of patients as low-risk compared with 58.1% (95% CI 56.6% to 59.6%) identified as low-risk by EDACS (p<0.001). Major adverse cardiac events occurred in 0.4% (95% CI 0.2% to 0.9%) of patients classified as low-risk by the HEART Pathway compared with 1.0% (95% CI 0.7% to 1.5%) of patients identified as low-risk by EDACS (p<0.001). Thus, the HEART Pathway had a negative predictive value of 99.6% (95% CI 99.1% to 99.8%) for major adverse cardiac events compared with a negative predictive value of 99.0% (95% CI 98.5% to 99.3%) for EDACS. CONCLUSIONS: EDACS identifies a larger proportion of patients as low-risk than the HEART Pathway, but has a higher missed major adverse cardiac events rate at 30 days. Physicians will need to consider their risk tolerance when deciding whether to adopt the HEART Pathway or EDACS accelerated diagnostic pathway. TRIAL REGISTRATION NUMBER: NCT02056964.

Prehospital Trauma Scene and Transport Times for Pediatric and Adult Patients.

INTRODUCTION: Increased out-of-hospital time is associated with worse outcomes in trauma. Sparse literature exists comparing prehospital scene and transport time management intervals between adult and pediatric trauma patients. National Emergency Medical Services guidelines recommend that trauma scene time be less than 10 minutes. The objective of this study was to examine prehospital time intervals in adult and pediatric trauma patients. METHODS: We performed a retrospective cohort study of blunt and penetrating trauma patients in a five-county region in North Carolina using prehospital records. We included patients who were transported emergency traffic directly from the scene by ground ambulance to a Level I or Level II trauma center between 2013-2018. We defined pediatric patients as those less than 16 years old. Urbanicity was controlled for using the Centers for Medicare and Medicaid's Ambulance Fee Schedule. We performed descriptive statistics and linear mixed-effects regression modeling. RESULTS: A total of 2179 records met the study criteria, of which 2077 were used in the analysis. Mean scene time was 14.2 minutes (95% confidence interval [CI], 13.9-14.5) and 35.3% (n = 733) of encounters had a scene time of 10 minutes or less. Mean transport time was 17.5 minutes (95% CI, 17.0-17.9). Linear mixed-effects regression revealed that scene times were shorter for pediatric patients (p<0.0001), males (p=0.0016), penetrating injury (p<0.0001), and patients with blunt trauma in rural settings (p=0.005), and that transport times were shorter for males (p = 0.02), non-White patients (p<0.0001), and patients in urban areas (p<0.0001). CONCLUSION: This study population largely missed the 10-minute scene time goal. Demographic and patient factors were associated with scene and transport times. Shorter scene times occurred with pediatric patients, males, and among those with penetrating trauma. Additionally, suffering blunt trauma while in a rural environment was associated with shorter scene time. Males, non-White patients, and patients in urban environments tended to have shorter transport times. Future studies with outcomes data are needed to identify factors that prolong out-of-hospital time and to assess the impact of out-of-hospital time on patient outcomes.