Workplace Health Promotion Programs Available to Emergency Medical Services Clinicians in North Carolina.

BACKGROUND: Emergency medical services (EMS) clinicians demonstrate a high prevalence of chronic medical conditions that place them at risk for early mortality. Workplace health promotion programs improve health outcomes, but the availably of such programs for EMS clinicians has not been described. We investigate the availability, scope, and participation of workplace health promotion programs available to EMS clinicians in North Carolina (NC). METHODS: We administered an electronic survey based on the Centers for Disease Control and Prevention Worksite Health ScoreCard to key representatives of EMS agencies within NC that provide primarily transport-capable 9-1-1 response with ground ambulances. We collected information on agency size, rurality, elements of health promotion programs offered, incentives for participation, and participation rate. We calculated descriptive statistics using frequency and percentage for worksite and health promotion program characteristics. We compared the participation rate for agencies who did and did not incentivize participation using Fisher's exact test. RESULTS: Complete responses were received from 69 of 92 agencies (response = 75%) that collectively employ 6679 EMS clinicians [median employees per agency 71 (IQR 50-131)]. Most agencies (88.4%, 61/69) offered at least one element of a worksite health program, but only 13.0% (9/69) offered all elements of a worksite health program. In descending order, the availability of program elements were employee assistance programs (73.9%, 51/69), supportive physical and social environment (66.7%, 46/69), health education (62.3%, 43/69), health risk assessments (52.2%, 36/69), and organization culture of health promotion (20.3%, 14/69). Of agencies with programs, few (11.5%, 7/61) required participation, but most (59.0%, 36/61) offered incentives to participate. Participation rates were <25% among nearly all of the agencies that did not offer incentives, but >50% among most agencies that did offer incentives (p < 0.001). CONCLUSION: While most agencies offer at least one element of a worksite health promotion program, few agencies offer all elements and participation rates are low.

Rural EMS STEMI Patients - Why the Delay to PCI?

BACKGROUND: The objective of this study is to identify patient and EMS agency factors associated with timely reperfusion of patients with ST-elevation myocardial infarction (STEMI). METHODS: We conducted a cohort study of adult patients (≥18 years old) with STEMI activations from 2016 to 2020. Data was obtained from a regional STEMI registry, which included eight rural county EMS agencies and three North Carolina percutaneous coronary intervention (PCI) centers. On each patient, prehospital and in-hospital time intervals were abstracted. The primary outcome was the ability to achieve the 90-minute EMS FMC to PCI time goal (yes vs. no). We used generalized estimating equations accounting for within-agency clustering to evaluate the association between patient and agency factors and meeting first medical contact (FMC) to PCI time goal while accounting for clustering within the agency. RESULTS: Among 365 rural STEMI patients 30.1% were female (110/365) with a mean age of 62.5 ± 12.7 years. PCI was performed within the time goal in 60.5% (221/365) of encounters. The FMC to PCI time goal was met in 45.5% (50/110) of women vs 69.8% (178/255) of men (p < 0.001). The median PCI center activation time was 12 min (IQR 7-19) in the group that received PCI within the time goal compared to 21 min (IQR 10-37) in the cohort that did not. After adjusting for loaded mileage and other clinical variables (e.g., pulse rate, hypertension etc.), the male sex was associated with an improved chance of meeting the goal of FMC to PCI (aOR: 2.94; 95% CI 2.11-4.10) compared to the female sex. CONCLUSION: Nearly 40% of rural STEMI patients transported by EMS failed to receive FMC to PCI within 90 min. Women were less likely than men to receive reperfusion within the time goal, which represents an important health care disparity.

Does Single Dose Epinephrine Improve Outcomes for Patients with Out-of-Hospital Cardiac Arrest and Bystander CPR or a Shockable Rhythm?

BACKGROUND: A single dose epinephrine protocol (SDEP) for out-of-hospital cardiac arrest (OHCA) achieves similar survival to hospital discharge (SHD) rates as a multidose epinephrine protocol (MDEP). However, it is unknown if a SDEP improves SHD rates among patients with a shockable rhythm or those receiving bystander cardiopulmonary resuscitation (CPR). METHODS: This pre-post study, spanning 11/01/2016-10/29/2019 at 5 North Carolina EMS systems, compared pre-implementation MDEP and post-implementation SDEP in patients ≥18 years old with non-traumatic OHCA. Data on initial rhythm type, performance of bystander CPR, and the primary outcome of SHD were sourced from the Cardiac Arrest Registry to Enhance Survival. We compared SDEP vs MDEP performance in each rhythm (shockable and non-shockable) and CPR (bystander CPR or no bystander CPR) subgroup using Generalized Estimating Equations to account for clustering among EMS systems and to adjust for age, sex, race, witnessed arrest, arrest location, AED availability, EMS response interval, and presence of a shockable rhythm or receiving bystander CPR. The interaction of SDEP implementation with rhythm type and bystander CPR was evaluated. RESULTS: Of 1690 patients accrued (899 MDEP, 791 SDEP), 19.2% (324/1690) had shockable rhythms and 38.9% (658/1690) received bystander CPR. After adjusting for confounders, SHD was increased after SDEP implementation among patients with bystander CPR (aOR 1.61, 95%CI 1.03-2.53). However, SHD was similar in the SDEP cohort vs MDEP cohort among patients without bystander CPR (aOR 0.81, 95%CI 0.60-1.09), with a shockable rhythm (aOR 0.96, 95%CI 0.48-1.91), and with a non-shockable rhythm (aOR 1.26, 95%CI 0.89-1.77). In the adjusted model, the interaction between SDEP implementation and bystander CPR was significant for SHD (p = 0.002). CONCLUSION: Adjusting for confounders, the SDEP increased SHD in patients who received bystander CPR and there was a significant interaction between SDEP and bystander CPR. Single dose epinephrine protocol and MDEP had similar SHD rates regardless of rhythm type.

Performance of the European Society of Cardiology 0/1-hour algorithm with high-sensitivity cardiac troponin T at 90 days among patients with known coronary artery disease.

BACKGROUND: The European Society of Cardiology (ESC) 0/1-h high sensitivity troponin T (hs-cTnT) algorithm does not differentiate risk based on known coronary artery disease (CAD: prior myocardial infarction [MI], coronary revascularization, or ≥ 70% coronary stenosis). We recently evaluated its performance among patients with known CAD at 30-days, but little is known about its longer-term risk prediction. The objective of this study is to determine and compare the performance of the algorithm at 90-days among patients with and without known CAD. METHODS: We performed a pre-planned subgroup analysis of the STOP-CP cohort, which prospectively enrolled ED patients ≥21 years old with symptoms suggestive of ACS without ST-elevation on initial ECG across 8 US sites (1/25/2017-9/6/2018). Participants with 0- and 1-h hs-cTnT measures (Roche, Basel, Switzerland) were stratified into rule-out, observe, and rule-in groups using the ESC 0/1-h algorithm. Algorithm performance was tested among patients with or without known CAD, as determined by the treating provider. The primary outcome was cardiac death or MI at 90-days. Fisher's exact tests were used to compare 90-day event and rule-out rates between patients with and without known CAD. Negative predictive values (NPVs) for 90-day cardiac death or MI with exact 95% confidence intervals were calculated and compared using Fisher's exact test. RESULTS: The STOP-CP study accrued 1430 patients, of which 31.4% (449/1430) had known CAD. Cardiac death or MI at 90 days was more common in patients with known CAD than in those without [21.2% (95/449) vs. 10.0% (98/981); p < 0.001]. Using the ESC 0/1-h algorithm, 39.6% (178/449) of patients with known CAD and 66.1% (648/981) of patients without known CAD were ruled-out (p < 0.001). Among rule-out patients, 90-day cardiac death or MI occurred in 3.4% (6/178) of patients with known CAD and 1.2% (8/648) without known CAD (p = 0.09). NPV for 90-day cardiac death or MI was 96.6% (95%CI 92.8-98.8) among patients with known CAD and 98.8% (95%CI 97.6-99.5) in patients without known CAD (p = 0.09). CONCLUSION: Patients with known CAD who were ruled-out using the ESC 0/1-h hs-cTnT algorithm had a high rate of missed 90-day cardiac events, suggesting that the ESC 0/1-h hs-cTnT algorithm may not be safe for use among patients with known CAD. TRIAL REGISTRATION: High-Sensitivity Cardiac Troponin T to Optimize Chest Pain Risk Stratification (STOP-CP; ClinicalTrials.gov: NCT02984436; https://clinicaltrials.gov/ct2/show/NCT02984436).

High-Sensitivity Cardiac Troponin and the 2021 AHA/ACC/ASE/CHEST/SAEM/SCCT/SCMR Guidelines for the Evaluation and Diagnosis of Acute Chest Pain.

The 2021 American Heart Association/American College of Cardiology/American Society of Echocardiography/American College of Chest Physicians/Society for Academic Emergency Medicine/Society of Cardiovascular Computed Tomography/Society for Cardiovascular Magnetic Resonance guidelines for the evaluation and diagnosis of acute chest pain make important recommendations that include the recognition of high-sensitivity cardiac troponin (hs-cTn) as the preferred biomarker, endorsement of 99th percentile upper reference limits to define myocardial injury, and the use of clinical decision pathways, as well as acknowledgment of the uniqueness of women and other patient subsets. Details on how to integrate hs-cTn into clinical practice are less extensively addressed. Clinicians should be aware of some of the analytical aspects related to hs-cTn assays regarding the limit of detection and the limit of quantitation and how they are used clinically, especially for the single sample strategy to rule out acute myocardial infarction. Likewise, it is important for clinicians to understand issues related to the derivation of the 99th percentile upper reference limit; the value of sex-specific 99th percentile upper reference limits; how to use changing concentrations (deltas) to facilitate diagnosis and risk stratification of patients with suspected acute coronary syndrome, including the differentiation of acute from chronic myocardial injury; and how to best integrate the use of hs-cTn with clinical decision pathways. With the use of hs-cTn, conditions such as type 2 myocardial infarction become more common, whereas others such as unstable angina become less frequent but still occur. Sections relating to these issues are included.

Derivation and validation of a high sensitivity troponin-T HEART pathway.

BACKGROUND: The HEART Pathway is widely used for chest pain risk stratification but has yet to be optimized for high sensitivity troponin T (hs-cTnT) assays. METHODS: We conducted a secondary analysis of STOP-CP, a prospective cohort study enrolling adult ED patients with symptoms suggestive of acute coronary syndrome at 8 sites in the United States (US). Patients had a 0- and 1-hour hs-cTnT measured and a HEAR score completed. A derivation set consisting of 729 randomly selected participants was used to derive a hs-cTnT HEART Pathway with rule-out, observation, and rule-in groups for 30-day cardiac death or myocardial infarction (MI). Optimal baseline and 1-hour troponin cutoffs were selected using generalized cross validation to achieve a negative predictive value (NPV) >99% for rule out and positive predictive value (PPV) >60% or maximum Youden index for rule-in. Optimal 0-1-hour delta values were derived using generalized cross validation to maximize the NPV for the rule-out group and PPV for the rule-in group. The hs-cTnT HEART Pathway performance was validated in the remaining cohort (n = 723). RESULTS: Among the 1452 patients, 30-day cardiac death or MI occurred in 12.7% (184/1452). Within the derivation cohort the optimal hs-cTnT HEART Pathway classified 36.5% (266/729) into the rule-out group, yielding a NPV of 99.2% (95% CI: 98.2-100) for 30-day cardiac death or MI. The rule-in group included 15.4% (112/729) with a PPV of 55.4% (95% CI: 46.2-64.6). In the validation cohort, the hs-cTnT HEART Pathway ruled-out 37.6% (272/723), of which 2 had 30-day cardiac death or MI, yielding a NPV of 99.3% (95% CI: 98.3-100). The rule-in group included 14.5% (105/723), yielding a PPV of 57.1% (95% CI: 47.7-66.6). CONCLUSIONS: A novel hs-cTnT HEART Pathway with serial 0- and 1-hour hs-cTnT measures has high NPV and moderate PPV for 30-day cardiac death or MI.

Emergency Medical Services Clinicians Have a High Prevalence of Metabolic Syndrome.

BACKGROUND: Metabolic syndrome is a constellation of risk factors associated with the development of cardiovascular disease and increased all-cause mortality. Data examining the prevalence of metabolic syndrome among emergency medical services (EMS) clinicians are limited. METHODS: We conducted a cross-sectional study of EMS clinicians and firefighters from three fire departments with transport-capable EMS divisions. Data were collected from compulsory annual physical exams for 2021 that included age, sex, race, body mass index (BMI), waist circumference, blood pressure, cholesterol levels, and hemoglobin A1c level. These data were used to determine the prevalence of meeting metabolic syndrome criteria. We calculated descriptive statistics of demographics, anthropometrics, and metabolic syndrome criteria for EMS clinicians and firefighters. We used chi-square tests to compare the proportion of EMS clinicians and firefighters meeting criteria for the whole group and among age groups of <40 years old, 40 to 59 years old, and ≥60 years old. We used logistic regression to estimate the odds of meeting criteria in EMS clinicians compared to firefighters, adjusted for age, sex, race, and BMI. RESULTS: We reviewed data for 65 EMS clinicians and 239 firefighters. For the combined cohort, 13.2% (40/304) were female and 95.1% (289/304) were White. The median age for EMS clinicians was 34 years versus 45 years in firefighters (p < 0.0001). Metabolic syndrome criteria were met in 27.3% (83/304) of the entire group. The prevalence of meeting criteria among EMS clinicians and firefighters was 33.9% (22/65) and 25.5% (61/239), respectively (p = 0.18). Of the participants who were younger than age 40, 36.6% (15/41) of EMS clinicians versus 9.1% (7/74) of firefighters met criteria for metabolic syndrome (p < 0.001). EMS clinicians had significantly higher odds of meeting criteria [OR 4.62 (p = 0.001)] compared to firefighters when adjusted for age, sex, race, and BMI. CONCLUSION: EMS clinicians had a high prevalence of metabolic syndrome at an early age, and had a higher adjusted odds of having metabolic syndrome compared to firefighters.

One and Done Epinephrine in Out-of-Hospital Cardiac Arrest? Outcomes in a Multiagency United States Study.

BACKGROUND: Cardiac arrest guidelines recommend epinephrine every 3-5 minutes during cardiac arrest resuscitation. However, it is unclear if multiple epinephrine doses are associated with improved outcomes. The objective of this study was to determine if a single-dose epinephrine protocol was associated with improved survival compared to traditional multidose protocols. METHODS: We conducted a pre-post study across five North Carolina EMS agencies from 11/1/2016 to 10/29/2019. Patients ≥18 years old with attempted resuscitation for non-traumatic prehospital cardiac arrest were included. Data were collected 1 year before and after implementation of the single-dose epinephrine protocol. Prior to implementation, all agencies used a multidose epinephrine protocol. The Cardiac Arrest Registry to Enhance Survival (CARES) was used to obtain patient outcomes. Study outcomes were survival to hospital discharge (primary) and return of spontaneous circulation (ROSC). Analysis was by intention to treat. Outcomes were compared pre- vs. post-implementation using generalized estimating equations to account for clustering within EMS agencies. Adjusted analyses included age, sex, race, shockable vs. non-shockable rhythm, witnessed arrest, automatic external defibrillator availability, EMS response interval, and bystander cardiopulmonary resuscitation. RESULTS: During the study period there were 1,690 encounters (899 pre- and 791 post-implementation). The population was 74.7% white, 61.1% male, and had a median age of 65 (IQR 53-76) years. Survival to hospital discharge was similar pre- vs. post-implementation [13.6% (122/899) vs. 15.4% (122/791); OR 1.19, 95%CI 0.89-1.59]. However, ROSC was more common post-implementation [42.3% (380/899) vs. 32.5% (257/791); OR 0.66, 95%CI 0.54-0.81]. After adjusting for covariates, the single-dose protocol was associated with similar survival to discharge rates (aOR 0.88, 95%CI 0.77-1.29), but with decreased ROSC rates (aOR 0.58, 95%CI 0.47-0.72). CONCLUSION: A prehospital single-dose epinephrine protocol was associated with similar survival to hospital discharge, but decreased ROSC rates compared to the traditional multidose epinephrine protocol.

Performance of Prehospital Use of Chest Pain Risk Stratification Tools: The RESCUE Study.

BACKGROUND: Emergency medical services (EMS) assesses millions of patients with chest pain each year. However, tools validated to risk stratify patients for acute coronary syndrome (ACS) and pulmonary embolism (PE) have not been translated to the prehospital setting. The objective of this study is to assess the prehospital performance of risk stratification scores for 30-day major adverse cardiac events (MACE) and PE. METHODS: A prospective observational cohort study of patients ≥21 years of age with acute chest pain who were transported by EMS in two North Carolina (NC) counties was conducted from 18 April 2018-2 January 2019. In this convenience sample, paramedics completed HEAR (history, electrocardiogram, age, risk factor), ED Assessment of Chest Pain Score (EDACS), Revised Geneva Score (RGS), and pulmonary embolism rule-out criteria (PERC) assessments on each patient. MACE (all-cause death, myocardial infarction, and revascularization) and PE at 30 days were determined by hospital records and NC Death Index. The positive (+LR) and negative likelihood ratios (-LR) of the risk scores for 30-day MACE and PE were calculated. RESULTS: During the study period, 82.1% (687/837) patients had all four risk score assessments. The cohort was 51.1% (351/687) female, 49.5% (340/687) African American, and had a mean age of 55.0 years (SD 16.0). At 30 days, MACE occurred in 7.4% (51/687), PE occurred in 0.9% (6/687), and the combined outcome occurred in 8.2% (56/687). The HEAR score had a - LR of 0.46 (95% CI 0.27-0.78) and + LR of 1.48 (95% CI 1.26-1.74) for 30-day MACE. EDACS had a - LR of 0.61 (95% CI 0.46-0.81) and + LR of 2.53 (95% CI 1.86-3.46) for 30-day MACE. The PERC score had a - LR of 0 (95% CI 0.0-1.4) and a + LR of 1.38 (95% CI 1.32-1.45) for 30-day PE. The RGS score had a - LR of 0 (95% CI 0.0-0.65) and a + LR of 2.36 (95% CI 2.16-2.57) for 30-day PE. The combination of a low-risk HEAR score and negative PERC evaluation had a - LR of 0.25 (95% CI 0.08-0.76) and a + LR of 1.21 (95% CI 1.21-1.30) for 30-day MACE or PE. CONCLUSION: The combination of a paramedic-obtained HEAR score and PERC evaluation performed best to exclude 30-day MACE and PE but was not sufficient for directing prehospital decision making.

Prehospital Time Disparities for Rural Patients with Suspected STEMI.

BACKGROUND: Rural patients with ST-elevation myocardial infarction (STEMI) may be less likely to receive prompt reperfusion therapy. This study's primary objective was to compare rural versus urban time intervals among a national cohort of prehospital patients with STEMI. METHODS: The ESO Data Collaborative (Austin, TX), containing records from 1,366 emergency medical services agencies, was queried for adult 9-1-1 responses with suspected STEMI from 1/1/2018-12/31/2019. The scene address for each encounter was classified as either urban or rural using the 2010 US Census Urban Area Zip Code Tabulation Area relationship. The primary outcome was total EMS interval (9-1-1 call to hospital arrival); a key secondary outcome was the proportion of responses that had EMS intervals under 60 minutes. Generalized estimating equations were used to determine whether rural versus urban differences in interval outcomes occurred when adjusting for loaded mileage (distance from scene to hospital) and patient and clinical encounter characteristics. RESULTS: Of 15,915,027 adult 9-1-1 transports, 23,655 records with suspected STEMI were included in the analysis. Most responses (91.6%, n = 21,661) occurred in urban settings. Median EMS interval was 37.6 minutes (IQR 30.0-48.0) in urban settings compared to 57.0 minutes (IQR 46.5-70.7) in rural settings (p < 0.01). Urban responses more frequently had EMS intervals <60 minutes (89.5%, n = 19,130), compared to rural responses (55.5%, n = 1,100, p < 0.01). After adjusting for loaded mileage, age, sex, race/ethnicity, abnormal vital signs, pain assessment, aspirin administration, and IV/IO attempt, rural location was associated with a 5.8 (95%CI 4.2-7.4) minute longer EMS interval than urban, and rural location was associated with a reduced chance of achieving EMS interval < 60 minutes (OR 0.40; 95%CI 0.33-0.49) as compared to urban location. CONCLUSION: In this large national sample, rural location was associated with significantly longer EMS interval for patients with suspected STEMI, even after accounting for loaded mileage.

Chest pain observation unit: A missed opportunity to initiate smoking cessation therapy.

BACKGROUND: Emergency Department Observation Unit (EDOU) patients with chest pain have a high prevalence of smoking, a key cardiovascular disease risk factor. While in the EDOU, there is an opportunity to initiate smoking cessation therapy (SCT), but this is not standard practice. This study aims to describe the missed opportunity for EDOU-initiated SCT by determining the proportion of smokers who receive SCT in the EDOU and within 1-year of EDOU discharge and to evaluate if SCT rates vary by race or sex. METHODS: We performed an observational cohort study of patients ≥18 years old being evaluated for chest pain in a tertiary care center EDOU from 3/1/2019-2/28/2020. Demographics, smoking history, and SCT were determined by electronic health record review. Emergency, family medicine, internal medicine, and cardiology records were reviewed to determine if SCT occurred within 1-year of their initial visit. SCT was defined as behavioral interventions or pharmacotherapy. Rates of SCT in the EDOU, 1-year follow-up period, and the EDOU through 1-year of follow-up were calculated. SCT rates from the EDOU through 1-year were compared between white vs. non-white and male vs. female patients using a multivariable logistic regression model including age, sex, and race. RESULTS: Among 649 EDOU patients, 24.0% (156/649) were smokers. These patients were 51.3% (80/156) female and 46.8% (73/156) white, with a mean age of 54.4 ± 10.5 years. From the EDOU encounter through 1-year of follow-up, only 33.3% (52/156) received SCT. In the EDOU, 16.0% (25/156) received SCT. During the 1-year follow-up period, 22.4% (35/156) had outpatient SCT. After adjusting for potential confounders, SCT rates from the EDOU through 1-year were similar among whites vs. non-whites (aOR 1.19, 95% CI 0.61-2.32) and males vs. females (aOR 0.79, 95% CI 0.40-1.56). CONCLUSIONS: SCT was rarely initiated in the EDOU among chest pain patients who smoke and most patients who did not receive SCT in the EDOU never received SCT at 1-year of follow-up. Rates of SCT were similarly low among race and sex subgroups. These data suggest an opportunity exists to improve health by initiating SCT in the EDOU.

Rarely tested or treated but highly prevalent: Hypercholesterolemia in ED observation unit patients with chest pain.

BACKGROUND: Hypercholesterolemia (HCL) is common among Emergency Department (ED) patients with chest pain but is typically not addressed in this setting. This study aims to determine whether a missed opportunity for Emergency Department Observation Unit (EDOU) HCL testing and treatment exists. METHODS: We conducted a retrospective observational cohort study of patients ≥18 years old evaluated for chest pain in an EDOU from 3/1/2019-2/28/2020. The electronic health record was used to determine demographics and if HCL testing or treatment occurred. HCL was defined by self-report or clinician diagnosis. Proportions of patients receiving HCL testing or treatment at 1-year following their ED visit were calculated. HCL testing and treatment rates at 1-year were compared between white vs. non-white and male vs. female patients using multivariable logistic regression models including age, sex, and race. RESULTS: Among 649 EDOU patients with chest pain, 55.8% (362/649) had known HCL. Among patients without known HCL, 5.9% (17/287, 95% CI 3.5-9.3%) had a lipid panel during their index ED/EDOU visit and 26.5% (76/287, 95% CI 21.5-32.0%) had a lipid panel within 1-year of their initial ED/EDOU visit. Among patients with known or newly diagnosed HCL, 54.0% (229/424, 95% CI 49.1-58.8%) were on treatment within 1-year. After adjustment, testing rates were similar among white vs. non-white patients (aOR 0.71, 95% CI 0.37-1.38) and men vs. women (aOR 1.32, 95% CI 0.69-2.57). Treatment rates were similar among white vs. non-white (aOR 0.74, 95% CI 0.53-1.03) and male vs. female (aOR 1.08, 95% CI 0.77-1.51) patients. CONCLUSIONS: Few patients were evaluated for HCL in the ED/EDOU or outpatient setting after their ED/EDOU encounter and only 54% of patients with HCL were on treatment during the 1-year follow-up period after the index ED/EDOU visit. These findings suggest a missed opportunity to reduce cardiovascular disease risk exists by evaluating and treating HCL in the ED or EDOU.

Diagnostic Performance of High-Sensitivity Cardiac Troponin T Strategies and Clinical Variables in a Multisite US Cohort.

BACKGROUND: European data support the use of low high-sensitivity troponin (hs-cTn) measurements or a 0/1-hour (0/1-h) algorithm for myocardial infarction to exclude major adverse cardiac events (MACEs) among patients in the emergency department with possible acute coronary syndrome. However, modest US data exist to validate these strategies. This study evaluated the diagnostic performance of an initial hs-cTnT measure below the limit of quantification (LOQ: 6 ng/L), a 0/1-h algorithm, and their combination with history, ECG, age, risk factors, and initial troponin (HEART) scores for excluding MACE in a multisite US cohort. METHODS: A prospective cohort study was conducted at 8 US sites, enrolling adult patients in the emergency department with symptoms suggestive of acute coronary syndrome and without ST-elevation on ECG. Baseline and 1-hour blood samples were collected, and hs-cTnT (Roche; Basel, Switzerland) was measured. Treating providers blinded to hs-cTnT results prospectively calculated HEART scores. MACE (cardiac death, myocardial infarction, and coronary revascularization) at 30 days was adjudicated. The proportion of patients with initial hs-cTnT measures below the LOQ and risk according to a 0/1-h algorithm was determined. The negative predictive value (NPV) was calculated for both strategies when used alone or with a HEART score. RESULTS: Among 1462 participants with initial hs-cTnT measures, 46.4% (678 of 1462) were women and 37.1% (542 of 1462) were Black with an age of 57.6±12.9 (mean±SD) years. MACEs at 30 days occurred in 14.4% (210 of 1462) of participants. Initial hs-cTnT measures below the LOQ occurred in 32.8% (479 of 1462), yielding an NPV of 98.3% (95% CI, 96.7-99.3) for 30-day MACEs. A low-risk HEART score with an initial hs-cTnT below the LOQ occurred in 20.1% (294 of 1462), yielding an NPV of 99.0% (95% CI, 97.0-99.8) for 30-day MACEs. A 0/1-h algorithm was complete in 1430 patients, ruling out 57.8% (826 of 1430) with an NPV of 97.2% (95% CI, 95.9-98.2) for 30-day MACEs. Adding a low HEART score to the 0/1-h algorithm ruled out 30.8% (441 of 1430) with an NPV of 98.4% (95% CI, 96.8-99.4) for 30-day MACEs. CONCLUSIONS: In a prospective multisite US cohort, an initial hs-cTnT below the LOQ combined with a low-risk HEART score has a 99% NPV for 30-day MACEs. The 0/1-h hs-cTnT algorithm did not achieve an NPV >99% for 30-day MACEs when used alone or with a HEART score. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02984436.

Prehospital Comparison of the HEAR and HE-MACS Scores for 30-Day Adverse Cardiac Events.

OBJECTIVE: The History, Electrocardiogram (ECG), Age, and Risk factor (HEAR) and History and ECG-only Manchester Acute Coronary Syndromes (HE-MACS) risk scores can risk stratify chest pain patients without troponin measures. The objective of this study was to determine if either risk score could achieve the ≥99% negative predictive value (NPV) required to rule out major adverse cardiovascular events (MACE; a composite of all-cause death, myocardial infarction, or coronary revascularization) at 30 days or the ≥50% positive predictive value (PPV) indicative of a patient possibly needing interventional cardiology. METHODS: We performed a pre-planned secondary analysis of the prospective multisite PARAHEART (n = 462, 12/2016-1/2018) and RESCUE (n = 767, 4/2018-1/2019) trials, which accrued adults ≥21 years old with acute non-traumatic chest pain transported by emergency medical services (EMS). Paramedics prospectively completed risk assessment forms. Very low risk was defined by a HEAR score of 0-1 or HE-MACS probability <4%. The primary outcome was 30-day MACE, which was determined by adjudication (PARAHEART) or electronic record review (RESCUE). NPV and PPV with exact 95% confidence intervals (95%CI) for 30-day MACE were calculated for each risk score and compared using McNemar's tests. RESULTS: Among the PARAHEART and RESCUE cohorts, 30-day MACE occurred in 18.8% (87/462) and 6.9% (53/767) of patients, respectively. In PARAHEART, 7.8% (36/462) were very low risk by HEAR score vs. 7.8% (36/462) by HE-MACS (p = 1.0). The HEAR score had a NPV of 97.2% (95%CI 91.9-100.0) vs. 91.7% (95%CI 82.6-100.0) for HE-MACS (p = 0.15). The HEAR and HE-MACS PPVs were similar [46.4% (95%CI 28.0-64.9) vs. 33.3% (95%CI 13.2-53.5) (p = 0.26)]. In RESCUE, the HEAR score identified 14.2% (109/767) as low risk compared to 8.3% (64/767) by HE-MACS (p < 0.001). In this cohort, the HEAR and HE-MACS scores had similar NPVs [98.2% (95%CI 95.7-100.0) vs. 98.4% (95%CI 95.4-100.0) (p = 0.89)] and PPVs [16.2% (95%CI 6.2-32.0) vs. 22.6% (95%CI 12.3-36.2) (p = 0.41)]. CONCLUSIONS: In two prehospital chest pain cohorts, neither the HEAR score nor HE-MACS achieved sufficient NPV or PPV to rule out or rule in 30-day MACE.

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.

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.

Scoring systems for the triage and assessment of short-term cardiovascular risk in patients with acute chest pain.

Acute chest pain is a common emergency department (ED) chief complaint. Evaluating patients for acute coronary syndrome is challenging because missing the diagnosis carries substantial morbidity, mortality, and medicolegal consequences. However, over-testing is associated with increased cost, overcrowding, and possible iatrogenic harm. Over the past two decades, multiple risk scoring systems have been developed to help emergency providers evaluate patients with acute chest pain. The ideal risk score balances safety by achieving high sensitivity and negative predictive value for major adverse cardiovascular events while also being effective in identifying a large proportion of patients for early discharge from the ED. This review examines contemporary risk scores used to risk stratify patients with acute chest pain.

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.

EMS blood collection from patients with acute chest pain reduces emergency department length of stay.

BACKGROUND: Expediting the measurement of serum troponin by leveraging EMS blood collection could reduce the diagnostic time for patients with acute chest pain and help address Emergency Department (ED) overcrowding. However, this practice has not been examined among an ED chest pain patient population in the United States. METHODS: A prospective observational cohort study of adults with non-traumatic chest pain without ST-segment elevation myocardial infarction was conducted in three EMS agencies between 12/2016-4/2018. During transport, paramedics obtained a patient blood sample that was sent directly to the hospital core lab for troponin measurement. On ED arrival HEART Pathway assessments were completed by ED providers as part of standard care. ED providers were blinded to troponin results from EMS blood samples. To evaluate the potential impact on length of stay (LOS), the time difference between EMS blood draw and first clinical ED draw was calculated. To determine the safety of using troponin measures from EMS blood samples, the diagnostic performance of the HEART Pathway for 30-day major adverse cardiac events (MACE: composite of cardiac death, myocardial infarction (MI), coronary revascularization) was determined using EMS troponin plus arrival ED troponin and EMS troponin plus a serial 3-h ED troponin. RESULTS: The use of EMS blood samples for troponin measures among 401 patients presenting with acute chest pain resulted in a mean potential reduction in LOS of 72.5 ± SD 35.7 min. MACE at 30 days occurred in 21.0% (84/401), with 1 cardiac death, 78 MIs, and 5 revascularizations without MI. Use of the HEART Pathway with EMS and ED arrival troponin measures yielded a NPV of 98.0% (95% CI: 89.6-100). NPV improved to 100% (95% CI: 92.9-100) when using the EMS and 3-h ED troponin measures. CONCLUSIONS: EMS blood collection used for core lab ED troponin measures could significantly reduce ED LOS and appears safe when integrated into the HEART Pathway.