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).

Validation of the ACC Expert Consensus Decision Pathway for Patients With Chest Pain

BACKGROUND

The American College of Cardiology (ACC) recently published an Expert Consensus Decision Pathway for chest pain.

OBJECTIVES

The purpose of this study was to validate the ACC Pathway in a multisite U.S.

COHORT

METHODS

An observational cohort study of adults with possible acute coronary syndrome was conducted. Patients were accrued from 5 U.S. Emergency Departments (November 1, 2020, to July 31, 2022). ECGs and 0- and 2-hour high-sensitivity troponin (Beckman Coulter) measures were used to stratify patients according to the ACC Pathway. The primary safety outcome was 30-day all-cause death or myocardial infarction (MI). Efficacy was defined as the proportion stratified to the rule-out zone. Negative predictive value for 30-day death or MI was assessed among the whole cohort and in a subgroup of patients with coronary artery disease (CAD) (prior MI, revascularization, or ≥70% coronary stenosis).

RESULTS

ACC Pathway assessments were complete in 14,395 patients, of whom 51.7% (7,437 of 14,395) were women with a median age of 56 years (Q1-Q3: 44-68 years). Known CAD was present in 23.5% (3,386 of 14,395) and 30-day death or MI occurred in 8.1% (1,168 of 14,395). The ACC Pathway had an efficacy of 48.1% (95% CI: 47.3%-49.0%). Among patients in the rule-out zone, 0.3% (22 of 6,930) had death or MI at 30 days, yielding a negative predictive value of 99.7% (95% CI: 99.5%-99.8%). In patients with known CAD, 20.0% (676 of 3,386) were classified to the rule-out zone, of whom 1.5% (10 of 676) had death or MI.

CONCLUSIONS

The ACC expert consensus decision pathway was safe and efficacious. However, it may not be safe for use among patients with known CAD.

Accelerated magnetocardiography in the evaluation of patients with suspected cardiac ischemia: The MAGNETO trial

Background

Diagnosing ischemia in emergency department (ED) patients with suspected acute coronary syndrome (sACS) is challenging with equivocal disposition of intermediate risk patients.

Objective

Compare sensitivity and specificity of magnetocardiography (MCG) versus standard of care (SOC) stress testing in diagnosing myocardial ischemia.

Methods

Multicenter, prospective, observational cohort study. ED patients with sACS and HEART score ≥ 3 underwent 90 s noninvasive MCG to detect myocardial ischemia. Results were blinded to the patient's clinicians. MCGs were read independently by 3 physicians blinded to clinical data. Myocardial ischemia was ≥70 % epicardial coronary artery stenosis, revascularization within 30 days, or 30-day major adverse cardiac events (MACE). Time to first test (TTT) and patient satisfaction for MCG and SOC were compared.

Results

Of enrolled patients (N = 390) (mean age 59 ± 12 years, 45 % female), 99 (25 %) underwent a non-invasive stress test: 42 (14 %) diagnosed with ischemia. MCG sensitivity was 66.7 % (50.5-80.4 %, 95 % CI) and specificity 57.1 % (50.0-63.3 %, 95 % CI) for detecting coronary ischemia. Noninvasive stress testing (stress echo, nuclear stress, and exercise stress) had the same sensitivity 66.7 % (95 % CI 29.9 % to 92.5 %) and a specificity of 89.9 % (95 % CI 81.7-95.3 %). Mean TTT was shorter for MCG, 3.18 h (SD 1.91) vs. SOC stress testing 22.71 (SD 15.23), p < 0.0001. Mean patient experience was MCG 4.7 versus 3.0 SOC stress testing (p < 0.0001).

Conclusion

MCG provides similar sensitivity and lower specificity as non-invasive stress testing in ED sACS patients. Time to test is shorter for MCG with higher patient satisfaction scores.

Is rapid acute coronary syndrome evaluation with high-sensitivity cardiac troponin less costly? An economic evaluation

Objective

Protocols to evaluate for myocardial infarction (MI) using high-sensitivity cardiac troponin (hs-cTn) have the potential to drive costs upward due to the added sensitivity. We performed an economic evaluation of an accelerated protocol (AP) to evaluate for MI using hs-cTn to identify changes in costs of treatment and length of stay compared with conventional testing.

Methods

We performed a planned secondary economic analysis of a large, cluster randomized trial across nine emergency departments (EDs) from July 2020 to April 2021. Patients were included if they were 18 years or older with clinical suspicion for MI. In the AP, patients could be discharged without further testing at 0 h if they had a hs-cTnI < 4 ng/L and at 1 h if the initial value were 4 ng/L and the 1-h value ≤7 ng/L. Patients in the standard of care (SC) protocol used conventional cTn testing at 0 and 3 h. The primary outcome was the total cost of treatment, and the secondary outcome was ED length of stay.

Results

Among 32,450 included patients, an AP had no significant differences in cost (+$89, CI: -$714, $893 hospital cost, +$362, CI: -$414, $1138 health system cost) or ED length of stay (+46, CI: -28, 120 min) compared with the SC protocol. In lower acuity, free-standing EDs, patients under the AP experienced shorter length of stay (-37 min, CI: -62, 12 min) and reduced health system cost (-$112, CI: -$250, $25).

Conclusion

Overall, the implementation of AP using hs-cTn does not result in higher costs.

European Society of Cardiology 0/1-hour algorithm (high-sensitivity cardiac troponin T) performance across distinct age groups

BACKGROUND

To determine if the European Society of Cardiology 0/1-hour (ESC 0/1-h) algorithm with high-sensitivity cardiac troponin T (hs-cTnT) meets the ≥99% negative predictive value (NPV) safety threshold for 30-day cardiac death or myocardial infarction (MI) in older, middle-aged and young subgroups.

METHODS

We conducted a subgroup analysis of adult emergency department patients with chest pain prospectively enrolled from eight US sites (January 2017 to September 2018). Patients were stratified into rule-out, observation and rule-in zones using the hs-cTnT ESC 0/1-h algorithm and classified as older (≥65 years), middle aged (46-64 years) or young (21-45 years). Patients had 0-hour and 1-hour hs-cTnT measures (Roche Diagnostics) and a History, ECG, Age, Risk factor and Troponin (HEART) score. Fisher's exact tests compared rule-out and 30-day cardiac death or MI rates between ages. NPVs with 95% CIs were calculated for the ESC 0/1-h algorithm with and without the HEART score.

RESULTS

Of 1430 participants, 26.9% (385/1430) were older, 57.4% (821/1430) middle aged and 15.7% (224/1430) young. Cardiac death or MI at 30 days occurred in 12.8% (183/1430). ESC 0/1-h algorithm ruled out 35.6% (137/385) of older, 62.1% (510/821) of middle-aged and 79.9% of (179/224) young patients (p<0.001). NPV for 30-day cardiac death or MI was 97.1% (95% CI 92.7% to 99.2%) among older patients, 98.4% (95% CI 96.9% to 99.3%) in middle-aged patients and 99.4% (95% CI 96.9% to 100%) among young patients. Adding a HEART score increased NPV to 100% (95% CI 87.7% to 100%) for older, 99.2% (95% CI 97.2% to 99.9%) for middle-aged and 99.4% (95% CI 96.6% to 100%) for young patients.

CONCLUSIONS

In older and middle-aged adults, the hs-cTnT ESC 0/1-h algorithm was unable to reach a 99% NPV for 30-day cardiac death or MI unless combined with a HEART score.

TRIAL REGISTRATION NUMBER

NCT02984436.

Safety and Effectiveness of the High-Sensitivity Cardiac Troponin HEART Pathway in Patients With Possible Acute Coronary Syndrome

BACKGROUND

The HEART Pathway (History, Electrocardiogram, Age, Risk factors, Troponin) can be used with high-sensitivity cardiac troponin to risk stratify emergency department patients with possible acute coronary syndrome. However, data on whether a high-sensitivity HEART Pathway (hs-HP) are safe and effective is lacking.

METHODS

An interrupted time series study was conducted at 5 North Carolina sites in 26 126 adult emergency department patients being investigated for possible acute coronary syndrome and without ST-segment-elevation myocardial infarction. Patients were accrued into 16-month preimplementation and postimplementation cohorts with a 6-month wash-in phase. Preimplementation (January 2019 to April 2020), the traditional HEART Pathway was used with 0- and 3-hour contemporary troponin measures (Siemens). In the postimplementation period (November 2020 to February 2022), a modified hs-HP was used with 0- and 2-hour high-sensitivity cardiac troponin (Beckman Coulter) measures. The primary safety and effectiveness outcomes were 30-day all-cause death or myocardial infarction and 30-day hospitalizations. These outcomes and early discharge rate (emergency department discharge without stress testing or coronary angiography) were determined from health records and death index data. Outcomes were compared preimplementation versus postimplementation using χ2 tests and multivariable logistic regression to adjust for potential confounders.

RESULTS

Preimplementation and postimplementation cohorts included 12 317 and 13 809 patients, respectively, of them 52.7% (13 767/26 126) were female with a median age of 54 years (interquartile range, 42-66). Rates of 30-day death or MI were 6.8% (945/13 809) postimplementation and 7.7% (948/12 317) preimplementation (adjusted odds ratio, 1.00 [95% CI, 0.90-1.11]). hs-HP implementation was associated with 19.9% (95% CI, 18.7%-21.1%) higher early discharges (post versus pre: 63.6% versus 43.7%; adjusted odds ratio, 2.22 [95% CI, 2.10-2.35]). The hs-HP was also associated with 16.1% (95% CI, 14.9%-17.3%) lower 30-day hospitalizations (postimplementation versus preimplementation, 31.4% versus 47.5%; adjusted odds ratio, 0.51 [95% CI, 0.48-0.54]). Among early discharge patients, death or myocardial infarction occurred in 0.5% (41/8780) postimplementation versus 0.4% (22/5383) preimplementation (P=0.61).

CONCLUSIONS

hs-HP implementation is associated with increased early discharges without increasing adverse events. These findings support the use of a modified hs-HP to improve chest pain care.

Performance of the 0/2-hour high-sensitivity cardiac troponin T diagnostic protocol in a multisite United States cohort

BACKGROUND

The diagnostic performance of the high-sensitivity troponin T (hs-cTnT) 0/2-h algorithm is unclear among U.S. emergency department (ED) patients with acute chest pain.

METHODS

A preplanned subgroup analysis of the STOP-CP cohort study was conducted. Participants with 0- and 2-h hs-cTnT measures prospectively enrolled at eight U.S. EDs from January 2017 to September 2018 were stratified into rule-out, observation, and rule-in zones using the hs-cTnT 0/2-h algorithm alone and combined with the history, electrocardiogram, age, and risk factor (HEAR) score. The primary outcome was adjudicated 30-day cardiac death or myocardial infarction (CDMI). The sensitivity and negative predictive value (NPV) of the 0/2-h rule-out zone and specificity and positive predictive value (PPV) of the rule-in zone for 30-day CDMI were calculated.

RESULTS

Of the 1307 patients accrued, 53.6% (700/1307) were male and 58.6% (762/1307) were White, with a mean ± SD age of 57.5 ± 12.7 years. At 30 days, CDMI occurred in 12.9% (168/1307) of participants. The 0/2-h algorithm ruled out 61.4% (802/1307) of patients. Among rule-out patients, 1.9% (15/802) experienced 30-day CDMI, resulting in a sensitivity of 91.1% (95% confidence interval [CI] 85.7%-94.9%) and NPV of 98.1% (95% CI 96.9%-98.9%). The 0/2-h algorithm ruled in 12.4% (162/1307) patients of whom 61.7% (100/162) experienced 30-day CDMI. The rule-in zone specificity was 94.6% (95% CI 93.1%-95.8%) and PPV was 61.7% (95% CI 53.8%-69.2%) for 30-day CDMI. The 0/2-h algorithm combined with HEAR score ruled out 30.7% (401/1307) of patients with a sensitivity and NPV for 30-day CDMI of 98.2% (95% CI 94.9%-99.6%) and 99.3% (95% CI 97.8%-99.8%), respectively.

CONCLUSIONS

The hs-cTnT 0/2-h algorithm ruled out most patients. With NPV of <99% for 30-day CDMI, the hs-cTnT 0/2-h algorithm, many emergency physicians may not consider it safe to use for U.S. ED patients. When combined with a low-risk HEAR score, NPV was >99% for 30-day CDMI at the cost of reduced efficacy.

Sex and race differences in the performance of the European Society of Cardiology 0/1-h algorithm with high-sensitivity troponin T

The diagnostic performance of the high-sensitivity troponin T (hs-cTnT) European Society of Cardiology (ESC) 0/1-h algorithm in sex and race subgroups of US Emergency Department (ED) patients is unclear. A pre-planned subgroup analysis of the STOP-CP cohort study was conducted. Participants with 0- and 1-h hs-cTnT measures from eight US EDs (1/2017 to 9/2018) were stratified into rule-out, observation, and rule-in zones using the hs-cTnT ESC 0/1 algorithm. The primary outcome was adjudicated 30-day cardiac death or MI. The proportion with the primary outcome in each zone was compared between subgroups with Fisher's exact tests. The negative predictive value (NPV) of the ESC 0/1 rule-out zone for 30-day CDMI was calculated and compared between subgroups using Fisher's exact tests. Of the 1422 patients enrolled, 54.2% (770/1422) were male and 58.1% (826/1422) white with a mean age of 57.6 ± 12.8 years. At 30 days, cardiac death or myocardial infarction (MI) occurred in 12.9% (183/1422) of participants. Among patients stratified to the rule-out zone, 30-day cardiac death or MI occurred in 1.1% (5/436) of women versus 2.1% (8/436) of men (p = .40) and 1.2% (4/331) of non-white patients versus 1.8% (9/490) of white patients (p = .58). The NPV for 30-day cardiac death or MI was similar among women versus men (98.9% [95% confidence interval, CI: 97.3-99.6] vs. 97.9% [95% CI: 95.9-99.1]; p = .40) and among white versus non-white patients (98.8% [95% CI: 96.9-99.7] vs. 98.2% [95% CI: 96.5-99.2]; p = .39). NPVs <99% in each subgroup suggest the hs-cTnT ESC 0/1-h algorithm may not be safe for use in US EDs. Trial Registration: High-Sensitivity Cardiac Troponin T to Optimize Chest Pain Risk Stratification (STOP-CP; ClinicalTrials.gov: NCT02984436; https://clinicaltrials.gov/ct2/show/NCT02984436).

Validation of a Novel, Rapid Sepsis Diagnostic for Emergency Department Use

OBJECTIVES

To assess the in vitro IntelliSep test, a microfluidic assay that quantifies the state of immune activation by evaluating the biophysical properties of leukocytes, as a rapid diagnostic for sepsis.

DESIGN

Prospective cohort study.

SETTING

Five emergency departments (EDs) in Louisiana, Missouri, North Carolina, and Washington.

PATIENTS

Adult patients presenting to the ED with signs (two of four Systemic Inflammatory Response Syndrome criteria, where one must be temperature or WBC count) or suspicion (provider-ordered culture) of infection.

INTERVENTIONS

All patients underwent testing with the IntelliSep using ethylene diamine tetraacetic acid-anticoagulated whole blood followed by retrospective adjudication for sepsis by sepsis-3 criteria by a blinded panel of physicians.

MEASUREMENTS AND MAIN RESULTS

Of 599 patients enrolled, 572 patients were included in the final analysis. The result of the IntelliSep test is reported as the IntelliSep Index (ISI), ranging from 0.1 to 10.0, divided into three interpretation bands for the risk of sepsis: band 1 (low) to band 3 (high). The median turnaround time for ISI results was 7.2 minutes. The ISI resulted band 1 in 252 (44.1%), band 2 in 160 (28.0%), and band 3 in 160 (28.0%). Sepsis occurred in 26.6% (152 of 572 patients). Sepsis prevalence was 11.1% (95% CI, 7.5-15.7%) in band 1, 28.1% (95% CI, 21.3-35.8%) in band 2, and 49.4% (95% CI, 41.4-57.4%) in band 3. The Positive Percent Agreement of band 1 was 81.6% and the Negative Percent Agreement of band 3 was 80.7%, with an area under the receiver operating characteristic curve of 0.74. Compared with band 1, band 3 correlated with adverse clinical outcomes, including mortality, and resource utilization.

CONCLUSIONS

Increasing ISI interpretation band is associated with increasing probability of sepsis in patients presenting to the ED with suspected infection.

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.

Short-Stay Units vs Routine Admission From the Emergency Department in Patients With Acute Heart Failure: The SSU-AHF Randomized Clinical Trial

Importance

More than 80% of patients who present to the emergency department (ED) with acute heart failure (AHF) are hospitalized. With more than 1 million annual hospitalizations for AHF in the US, safe and effective alternatives are needed. Care for AHF in short-stay units (SSUs) may be safe and more efficient than hospitalization, especially for lower-risk patients, but randomized clinical trial data are lacking.

Objective

To compare the effectiveness of SSU care vs hospitalization in lower-risk patients with AHF.

Design, Setting, and Participants

This multicenter randomized clinical trial randomly assigned low-risk patients with AHF 1:1 to SSU or hospital admission from the ED. Patients received follow-up at 30 and 90 days post discharge. The study began December 6, 2017, and was completed on July 22, 2021. The data were analyzed between March 27, 2020, and November 11, 2023.

Intervention

Randomized post-ED disposition to less than 24 hours of SSU care vs hospitalization.

Main Outcomes and Measures

The study was designed to detect at least 1-day superiority for a primary outcome of days alive and out of hospital (DAOOH) at 30-day follow-up for 534 participants, with an allowance of 10% participant attrition. Due to the COVID-19 pandemic, enrollment was truncated at 194 participants. Before unmasking, the primary outcome was changed from DAOOH to an outcome with adequate statistical power: quality of life as measured by the 12-item Kansas City Cardiomyopathy Questionnaire (KCCQ-12). The KCCQ-12 scores range from 0 to 100, with higher scores indicating better quality of life.

Results

Of the 193 patients enrolled (1 was found ineligible after randomization), the mean (SD) age was 64.8 (14.8) years, 79 (40.9%) were women, and 114 (59.1%) were men. Baseline characteristics were balanced between arms. The mean (SD) KCCQ-12 summary score between the SSU and hospitalization arms at 30 days was 51.3 (25.7) vs 45.8 (23.8) points, respectively (P = .19). Participants in the SSU arm had 1.6 more DAOOH at 30-day follow-up than those in the hospitalization arm (median [IQR], 26.9 [24.4-28.8] vs 25.4 [22.0-27.7] days; P = .02). Adverse events were uncommon and similar in both arms.

Conclusions and Relevance

The findings show that the SSU strategy was no different than hospitalization with regard to KCCQ-12 score, superior for more DAOOH, and safe for lower-risk patients with AHF. These findings of lower health care utilization with the SSU strategy need to be definitively tested in an adequately powered study.

Trial Registration

ClinicalTrials.gov Identifier: NCT03302910.

Preventive Cardiovascular Care for Hypercholesterolemia in US Emergency Departments: A National Missed Opportunity

BACKGROUND

Hypercholesterolemia (HCL) affects nearly half of Emergency Department (ED) patients who present with possible acute coronary syndrome (ACS). However, it is unknown whether US ED providers obtain lipid panels, calculate 10-year atherosclerotic cardiovascular disease (ASCVD) risk, and prescribe cholesterol-lowering medications for these patients.

METHODS

We conducted a nationwide cross-sectional ED survey from April 18, 2023, to May 12, 2023. An electronic survey assessing current preventive HCL care practices for patients being evaluated for ACS. A convenience sample was obtained by sharing the survey with ED medical directors, chairs, and senior leaders using emergency medicine professional organization listservs and snowball sampling. Responding EDs were categorized as being associated with an academic medical center (AMC) or not (non-AMC).

RESULTS

During the 4-week study period, 110 EDs (50 AMC and 60 non-AMC EDs) across 39 states responded. Just 1.8% (2/110) stated that their providers obtain a lipid panel on at least half of patients with possible ACS and only one ED (0.9%) responded that its providers calculate 10-year ASCVD risk and prescribe cholesterol medication for the majority of eligible patients. Most reported never obtaining lipid panels (60.9%, 67/110), calculating 10-year ASCVD risk (55.5%, 61/110), or prescribing cholesterol-lowering medications (52.7%, 58/110).

CONCLUSIONS

The vast majority of US ED providers do not provide preventive cardiovascular care for patients presenting with possible ACS. Most ED providers do not evaluate for HCL, calculate ASCVD risk, or prescribe cholesterol-lowering medications for these patients.

Methods of the PivotaL triAl of the Atellica VTLi point of care emergencY dePartment high sensitivity troponin evalUationS

BACKGROUND

The Atellica® VTLi point-of-care (POC) High Sensitivity Cardiac Troponin-I (hs-cTnI) assay is intended for use as an aid in the diagnosis of myocardial infarction (MI). Our primary objective is to assess its diagnostic performance in patients presenting with suspected acute coronary syndrome (ACS).

METHODS

This prospective observational study will enrol ∼1500 patients at ∼20 U.S. Emergency Departments. After informed consent, adults (>21 years of age) with suspected ACS, and no prior enrollment in this study, will provide a fingerstick and venous blood sample within 2 h of ED presentation, >2 to ≤4 h, and >4 to ≤9 h (max. blood draw = 60 mL). HEART and EDACS scores will be prospectively documented. Patients without the first blood draw may be enrolled if the second draw was obtained. Capillary and venous whole blood will undergo Atellica VTLi assay testing, with remaining venous sample processed to plasma and run. All results will be blinded to the clinical care team. Site operators will undergo a 3-day familiarization period. Quality control testing will be performed daily. At 30 ± 3 days, patient mortality status, major adverse cardiac events, and rehospitalizations will be determined. A clinical endpoint adjudication committee, blinded to hs-cTnI VTLi result, will define the final diagnosis. Sensitivity, specificity, and predictive values will describe the assay performance.

RESULTS

We expect study completion within 114 weeks of enrollment of the first patient.

CONCLUSIONS

It is anticipated that the Atellica VTLi hs-cTnI assay validation study will define a performance equivalent to lab-based hs-cTnI, with results within ∼8 min at the point of care.

Delayed first medical contact to reperfusion time increases mortality in rural emergency medical services patients with ST-elevation myocardial infarction

BACKGROUND

ST-elevation myocardial infarction (STEMI) guidelines recommend an emergency medical services (EMS) first medical contact (FMC) to percutaneous coronary intervention (PCI) time of ≤90 min. The primary objective of this study was to evaluate the association between FMC to PCI time and mortality in rural STEMI patients.

METHODS

We conducted a cohort study of patients ≥18 years old with STEMI activations from January 2016 to March 2020. Data were obtained from a rural North Carolina Regional STEMI Data Registry, which included eight rural EMS agencies and three PCI centers, the National Cardiovascular Data Registry, and the EMS electronic health record. Prehospital and in-hospital time intervals were digitally abstracted. The outcome of index hospitalization mortality was compared between patients who did and did not meet FMC to PCI time goal using Fisher's exact tests. Negative predictive value (NPV) for index hospitalization death was calculated with 95% confidence intervals (CIs). A receiver operating characteristic curve was constructed and an optimal FMC to PCI time goal was identified by maximizing NPV to prevent index hospitalization death.

RESULTS

Among 365 rural EMS STEMI patients, 30.1% (110/365) were female with a mean ± SD age of 62.5 ± 12.7 years. PCI was performed within the 90-min time goal in 60.5% (221/365) of patients. Among these patients, 3% (11/365) died during initial STEMI hospitalization, with 1.4% (3/221) mortality in the group that met the 90-minute time goal compared to 5.6% (8/144) in patients exceeding the time goal (p = 0.03). Meeting the 90-min time goal yielded a 98.6% (95% CI 96.1%-99.7%) NPV for index death. A 78-min FMC to PCI time was the optimal cut point, yielding a NPV for index mortality of 99.3% (95% CI 96.1%-100%).

CONCLUSIONS

Death among rural patients with STEMI was four times more likely when they did not receive PCI within 90 min.

Race differences in cardiac testing rates for patients with chest pain in a multisite cohort

BACKGROUND

Identifying and eliminating racial health care disparities is a public health priority. However, data evaluating race differences in emergency department (ED) chest pain care are limited.

METHODS

We conducted a secondary analysis of the High-Sensitivity Cardiac Troponin T to Optimize Chest Pain Risk Stratification (STOP-CP) cohort, which prospectively enrolled adults with symptoms suggestive of acute coronary syndrome without ST-elevation from eight EDs in the United States from 2017 to 2018. Race was self-reported by patients and abstracted from health records. Rates of 30-day noninvasive testing (NIT), cardiac catheterization, revascularization, and adjudicated cardiac death or myocardial infarction (MI) were determined. Logistic regression was used to evaluate the association between race and 30-day outcomes with and without adjustment for potential confounders.

RESULTS

Among 1454 participants, 42.3% (615/1454) were non-White. At 30 days NIT occurred in 31.4% (457/1454), cardiac catheterization in 13.5% (197/1454), revascularization in 6.0% (87/1454), and cardiac death or MI in 13.1% (190/1454). Among Whites versus non-Whites, NIT occurred in 33.8% (284/839) versus 28.1% (173/615; odds ratio [OR] 0.76, 95% confidence interval [CI] 0.61-0.96) and catheterization in 15.9% (133/839) versus 10.4% (64/615; OR 0.62, 95% CI 0.45-0.84). After covariates were adjusted for, non-White race remained associated with decreased 30-day NIT (adjusted OR [aOR] 0.71, 95% CI 0.56-0.90) and cardiac catheterization (aOR 0.62, 95% CI 0.43-0.88). Revascularization occurred in 6.9% (58/839) of Whites versus 4.7% (29/615) of non-Whites (OR 0.67, 95% CI 0.42-1.04). Cardiac death or MI at 30 days occurred in 14.2% of Whites (119/839) versus 11.5% (71/615) of non-Whites (OR 0.79 95% CI 0.57-1.08). After adjustment there was still no association between race and 30-day revascularization (aOR 0.74, 95% CI 0.45-1.20) or cardiac death or MI (aOR 0.74, 95% CI 0.50-1.09).

CONCLUSIONS

In this U.S. cohort, non-White patients were less likely to receive NIT and cardiac catheterization compared to Whites but had similar rates of revascularization and cardiac death or MI.

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.

Personalized diagnosis in suspected myocardial infarction

BACKGROUND

In suspected myocardial infarction (MI), guidelines recommend using high-sensitivity cardiac troponin (hs-cTn)-based approaches. These require fixed assay-specific thresholds and timepoints, without directly integrating clinical information. Using machine-learning techniques including hs-cTn and clinical routine variables, we aimed to build a digital tool to directly estimate the individual probability of MI, allowing for numerous hs-cTn assays.

METHODS

In 2,575 patients presenting to the emergency department with suspected MI, two ensembles of machine-learning models using single or serial concentrations of six different hs-cTn assays were derived to estimate the individual MI probability (ARTEMIS model). Discriminative performance of the models was assessed using area under the receiver operating characteristic curve (AUC) and logLoss. Model performance was validated in an external cohort with 1688 patients and tested for global generalizability in 13 international cohorts with 23,411 patients.

RESULTS

Eleven routinely available variables including age, sex, cardiovascular risk factors, electrocardiography, and hs-cTn were included in the ARTEMIS models. In the validation and generalization cohorts, excellent discriminative performance was confirmed, superior to hs-cTn only. For the serial hs-cTn measurement model, AUC ranged from 0.92 to 0.98. Good calibration was observed. Using a single hs-cTn measurement, the ARTEMIS model allowed direct rule-out of MI with very high and similar safety but up to tripled efficiency compared to the guideline-recommended strategy.

CONCLUSION

We developed and validated diagnostic models to accurately estimate the individual probability of MI, which allow for variable hs-cTn use and flexible timing of resampling. Their digital application may provide rapid, safe and efficient personalized patient care.

TRIAL REGISTRATION NUMBERS

Data of following cohorts were used for this project: BACC ( www.

CLINICALTRIALS

gov ; NCT02355457), stenoCardia ( www.

CLINICALTRIALS

gov ; NCT03227159), ADAPT-BSN ( www.australianclinicaltrials.gov.au ; ACTRN12611001069943), IMPACT ( www.australianclinicaltrials.gov.au , ACTRN12611000206921), ADAPT-RCT ( www.anzctr.org.au ; ANZCTR12610000766011), EDACS-RCT ( www.anzctr.org.au ; ANZCTR12613000745741); DROP-ACS ( https://www.umin.ac.jp , UMIN000030668); High-STEACS ( www.

CLINICALTRIALS

gov ; NCT01852123), LUND ( www.

CLINICALTRIALS

gov ; NCT05484544), RAPID-CPU ( www.

CLINICALTRIALS

gov ; NCT03111862), ROMI ( www.

CLINICALTRIALS

gov ; NCT01994577), SAMIE ( https://anzctr.org.au ; ACTRN12621000053820), SEIGE and SAFETY ( www.

CLINICALTRIALS

gov ; NCT04772157), STOP-CP ( www.

CLINICALTRIALS

gov ; NCT02984436), UTROPIA ( www.

CLINICALTRIALS

gov ; NCT02060760).

Emergency Department Observation Unit Patients Want Evaluation and Treatment for Hypercholesterolemia: A Health Belief Model Study

BACKGROUND

Hypercholesterolemia (HCL) is common among emergency department (ED) and ED observation unit (EDOU) patients with chest pain but is not typically addressed in these settings. The objective of this study was to assess patient attitudes towards EDOU-based HCL care using the Health Belief Model.

METHODS

We conducted a cross-sectional survey study among 100 EDOU patients ≥18 years-old evaluated for chest pain in the EDOU of a tertiary care center from September 1, 2020, to November 01, 2021. Five-point Likert-scale surveys were used to assess each Health Belief Model domain: Cues to Action, Perceived Susceptibility, Perceived Barriers, Perceived Self-Efficacy, and Perceived Benefits. Responses were categorized as agree or do not agree.

RESULTS

The participants were 49.0% (49/100) female, 39.0% (39/100) non-white, and had a mean age of 59.0 ± 12.4 years. Most (83.0% [83/100, 95% confidence interval (CI), 74.2%-89.8%]) agreed the EDOU is an appropriate place for HCL education and 52.0% (52/100, 95% CI, 41.8%-62.1%) were interested in talking with their EDOU care team about HCL. Regarding Perceived Susceptibility, 88.0% (88/100, 95% CI, 80.0%-93.6%) believed HCL to be bad for their health, while 41.0% (41/100, 95% CI, 31.3%-51.3%) believed medication costs could be a barrier. For Perceived Self-Efficacy, 76.0% (76/100, 95% CI, 66.4%-84.0%) were receptive to taking medications. Overall, 95.0% (95/100, 95% CI, 88.7%-98.4%) believed managing HCL would benefit their health.

CONCLUSIONS

This Health Belief Model-based survey indicates high patient interest in EDOU-initiated HCL care. Patients reported high rates of Perceived Susceptibility, Self-Efficacy, and Benefits and a minority found HCL therapy costs a barrier.

Rarely tested or treated but highly prevalent: Hypercholesterolemia in emergency department 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.

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.

Performance of the European Society of Cardiology 0/1-Hour Algorithm With High-Sensitivity Cardiac Troponin T Among Patients With Known Coronary Artery Disease

Importance

The European Society of Cardiology (ESC) 0/1-hour algorithm is a validated high-sensitivity cardiac troponin (hs-cTn) protocol for emergency department patients with possible acute coronary syndrome. However, limited data exist regarding its performance in patients with known coronary artery disease (CAD; prior myocardial infarction [MI], coronary revascularization, or ≥70% coronary stenosis).

Objective

To evaluate and compare the diagnostic performance of the ESC 0/1-hour algorithm for 30-day cardiac death or MI among patients with and without known CAD and determine if the algorithm could achieve the negative predictive value rule-out threshold of 99% or higher.

Design, Setting, and Participants

This was a preplanned subgroup analysis of the STOP-CP prospective multisite cohort study, which was conducted from January 25, 2017, through September 6, 2018, at 8 emergency departments in the US. Patients 21 years or older with symptoms suggestive of acute coronary syndrome without ST-segment elevation on initial electrocardiogram were included. Analysis took place between February and December 2022.

Interventions/Exposures

Participants with 0- and 1-hour high-sensitivity cardiac troponin T (hs-cTnT) measures were stratified into rule-out, observation, and rule-in zones using the ESC 0/1-hour hs-cTnT algorithm.

Main Outcomes and Measures

Cardiac death or MI at 30 days determined by expert adjudicators.

Results

During the study period, 1430 patients were accrued. In the cohort, 775 individuals (54.2%) were male, 826 (57.8%) were White, and the mean (SD) age was 57.6 (12.8) years. At 30 days, cardiac death or MI occurred in 183 participants (12.8%). Known CAD was present in 449 (31.4%). Among patients with known CAD, the ESC 0/1-hour algorithm classified 178 of 449 (39.6%) into the rule-out zone compared with 648 of 981 (66.1%) without CAD (P < .001). Among rule-out zone patients, 30-day cardiac death or MI occurred in 6 of 178 patients (3.4%) with known CAD and 7 of 648 (1.1%) without CAD (P < .001). The negative predictive value for 30-day cardiac death or MI was 96.6% (95% CI, 92.8-98.8) among patients with known CAD and 98.9% (95% CI, 97.8-99.6) in patients without known CAD (P = .04).

Conclusions and Relevance

Among patients with known CAD, the ESC 0/1-hour hs-cTnT algorithm was unable to safely exclude 30-day cardiac death or MI. This suggests that clinicians should be cautious if using the algorithm in patients with known CAD. The negative predictive value was significantly higher in patients without a history of CAD but remained less than 99%.

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.

Rural and socioeconomic differences in the effectiveness of the HEART Pathway accelerated diagnostic protocol

BACKGROUND

The HEART Pathway is a validated accelerated diagnostic protocol (ADP) for patients with possible acute coronary syndrome (ACS). This study aimed to compare the safety and effectiveness of the HEART Pathway based on patient rurality (rural vs. urban) or socioeconomic status (SES).

METHODS

We performed a preplanned subgroup analysis of the HEART Pathway Implementation Study. The primary outcomes were death or myocardial infarction (MI) and hospitalization at 30 days. Proportions were compared by SES and rurality with Fisher's exact tests. Logistic regression evaluated for interactions of ADP implementation with SES or rurality and changes in outcomes within subgroups.

RESULTS

Among 7245 patients with rurality and SES data, 39.9% (2887/7245) were rural and 22.2% were low SES (1607/7245). The HEART Pathway identified patients as low risk in 32.2% (818/2540) of urban versus 28.1% (425/1512) of rural patients (p = 0.007) and 34.0% (311/915) of low SES versus 29.7% (932/3137) high SES patients (p = 0.02). Among low-risk patients, 30-day death or MI occurred in 0.6% (5/818) of urban versus 0.2% (1/425) rural (p = 0.67) and 0.6% (2/311) with low SES versus 0.4% (4/932) high SES (p = 0.64). Following implementation, 30-day hospitalization was reduced by 7.7% in urban patients (adjusted odds ratio [aOR] 0.76, 95% confidence interval [CI] 0.66-0.87), 10.6% in low SES patients (aOR 0.68, 95% CI 0.54-0.86), and 4.5% in high SES patients (aOR 0.83, 95% CI 0.73-0.94). However, rural patients had a nonsignificant 3.3% reduction in hospitalizations.

CONCLUSIONS

HEART Pathway implementation decreased 30-day hospitalizations regardless of SES and for urban patients but not rural patients. The 30-day death or MI rate was similar among low-risk patients.

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.

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.

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.

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.

Age and the European Society of Cardiology 0/1-hour high sensitivity troponin T algorithm for the evaluation of patients with possible acute myocardial infarction: results from the STOP-CP study

Background

The European Society of Cardiology (ESC) 0/1-hour high sensitivity troponin (hs-cTn) algorithm is widely used in the evaluation of patients presenting to the Emergency Department (ED) with symptoms suspicious for non ST-segment elevation myocardial infarction (NSTEMI). The effect of increasing patient age with its use has not been studied in any detail.

Purpose

The objective of this secondary analysis of the STOP-CP (High Sensitivity Cardiac Troponin T to Optimize Chest Pain Risk Stratification) United States (US) multicenter study was to evaluate the efficacy and safety of use of the ESC 0/1-hour hs-cTnT algorithm in younger, middle-aged, and older patients.

Methods

Patients (≥21 years old) presenting to the (ED) with symptoms suggestive of NSTEMI were enrolled (1/25/2017–9/6/2018) at 8 US medical centers. The ESC hs-cTnT 0/1-hour hs-cTnT algorithm was used to place patients into rule-out, observe, and rule-in NSTEMI zones. Algorithm performance for rapid NSTEMI rule-out and 30-day adverse outcomes was studied in 3 patient age (years) intervals: younger (21–45). middle aged (46–64) and older (≥65). Major adverse cardiovascular events (MACE) consisted of cardiac death, myocardial infarction, or coronary revascularization at 30-days. Fisher's exact tests were used to compare NSTEMI ruled out and MACE rates between patient age intervals. Negative likelihood ratios (NLR) with 95% confidence interval (CI) were calculated for 30-day MACE.

Results

Overall 1430 participants were enrolled with 15.7% (224/1430) young, 57.4% (821/1430) middle-aged, and 26.9% (385/1430) being older. The ESC 0/1 hour hs-cTnT algorithm NSTEMI rule-out rates were 79.9% (179/224), 62.1% (510/821) and 35.6% (137/385) respectively for these age groups (p&lt;0.0001). The overall 30-day MACE rate was 14.2% (203/1430) with interval age rates of 7.1% (16/224) in younger, 13.1% (108/821) middle aged and 20.5% (79/385) older patients. Amongst NSTEMI ruled-out patients MACE occurred in 1.1% (2/179) of younger, 3.3% (17/510) middle aged and 2.9% (4/137) older individuals (p=0.320). NLR for 30-day MACE was 0.15 (95% CI 0.04, −0.54) in younger, 0.23 (95% CI 0.15–0.35) middle aged and 0.12 (95% CI 0.04–0.31) for older patients.

Conclusions

With increasing age ED patients were less often rapidly ruled out for NSTEMI during their initial cardiac evaluations. The STOP-CP US study demonstrated that older age interval alone was not an independent variable that increased the risk for 30-day MACE in patients ruled out for NSTEMI using the ESC 0/1 hour hs-cTnT algorithm. Our report suggests that cardiac risk stratification scores using age as an independent variable for predicting 30-day MACE in these patients require reevaluation.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Roche, Basel, Switzerland

Patients with known coronary artery disease who are ruled out for acute myocardial infarction using a high sensitivity troponin T 0/1-hour algorithm have increased 30-day major adverse cardiac events

Background

The European Society of Cardiology (ESC) 0/1-hour high sensitivity troponin (hs-cTn) algorithm is widely used in the evaluation of patients presenting to the Emergency Department (ED) with symptoms suspicious for non ST-segment elevation myocardial infarction (NSTEMI). There is limited data available for the use of this algorithm comparing NSTEMI rule-out rates and 30-day adverse outcomes in patients with and without known coronary artery disease (CA), defined as prior myocardial infarction [MI], coronary revascularization, or ≥70% coronary stenosis.

Purpose

The objective of this secondary analysis of the STOP-CP (High Sensitivity Cardiac Troponin T to Optimize Chest Pain Risk Stratification) United States (US) multicenter study was to compare the ESC 0/1-hour algorithm for rapid NSTEMI rule-out and 30-day adverse outcomes in patients with and without known CAD.

Methods

Patients (≥21 years old) presenting to the (ED) with symptoms suggestive of NSTEMI were enrolled (1/25/2017–9/6/2018) at 8 US medical centers. The ESC hs-cTnT 0/1-hour hs-cTnT algorithm was used to stratify patients into rule-out, observe, and rule-in zones. Algorithm performance for 30-day adverse outcomes was analyzed in patients with or without known CAD. Major adverse cardiovascular events (MACE) consisted of cardiac death, MI, or coronary revascularization. Fisher's exact tests were used to compare NSTEMI rule-out and 30-day MACE rates in patients with and without known CAD. Negative likelihood ratios (NLR) with a 95% confidence interval (CI) were calculated for 30-day MACE.

Results

Overall 1430 patients were enrolled. Of these 31.4% (449/1430) had known CAD while 14.2% (203 /1430) experienced 30-day MACE. Using the ESC 0/1-hour hs-cTnT algorithm 39.6% (178/449) of patients with known CAD were placed in the rule-out zone compared to 66.1% (648/981) without CAD (p&lt;0.0001). Of patients with known CAD 23.2% (104/449) had 30-day MACE compared to 10.1% (99/981) of those without known CAD (p&lt;0.0001). Additionally, amongst those patients placed in the rule-out zone, 30-day MACE occurred in 7.9% (14/178) of individuals with known CAD and 1.4% (9/648) of those without known CAD (p&lt;0.0001). NLR for 30-day MACE was 0.28 (95% CI 0.17–0.47) in patients with known CAD and 0.13 (95% CI 0.07–0.23) in those without CAD.

Conclusions

In the multicenter US STOP-CP study patients with known CAD were less often rapidly ruled out for NSTEMI and had higher 30-day MACE rates than those without known CAD. Patients with known CAD who were rapidly ruled out for NSTEMI had a higher 30-day MACE rate compared to those without known CAD. Our analysis suggests that patients with known CAD require further cardiac reevaluations whether they are ruled out for NSTEMI by the ESC 0/1 hour hs-cTnT algorithm or not.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Roche, Basel, Switzerland

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.

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.

Age differences in the safety and effectiveness of the HEART Pathway accelerated diagnostic protocol for acute chest pain

BACKGROUND

The HEART Pathway is a validated protocol for risk stratifying emergency department (ED) patients with possible acute coronary syndrome (ACS). Its performance in different age groups is unknown. The objective of this study is to evaluate its safety and effectiveness among older adults.

METHODS

A pre-planned subgroup analysis of the HEART Pathway implementation study was conducted. This prospective interrupted time series accrued adult ED patients with possible ACS who were without ST-elevation across three US sites from 11/2013-01/2016. After implementation, providers prospectively used the HEART Pathway to stratify patients as low-risk or non-low-risk. Patients were classified as older adults (≥65 years), middle-aged (46-64 years), and young (21-45 years). Primary safety and effectiveness outcomes were 30-day death or MI and hospitalization at 30 days, determined from health records, insurance claims, and death index data. Fisher's exact test compared low-risk proportions between groups. Sensitivity for 30-day death or MI and adjusted odds ratios (aORs) for hospitalization and objective cardiac testing were calculated.

RESULTS

The HEART Pathway implementation study accrued 8474 patients, of which 26.9% (2281/8474) were older adults, 45.5% (3862/8474) middle-aged, and 27.5% (2331/8474) were young. The HEART Pathway identified 7.4% (97/1303) of older adults, 32.0% (683/2131) of middle-aged, and 51.4% (681/1326) of young patients as low-risk (p < 0.001). The HEART Pathway was 98.8% (95% CI 97.1-100) sensitive for 30-day death or MI among older adults. Following implementation, the rate of 30-day hospitalization was similar among older adults (aOR 1.25, 95% CI 1.00-1.55) and cardiac testing increased (aOR 1.25, 95% CI 1.04-1.51).

CONCLUSION

The HEART Pathway identified fewer older adults as low-risk and did not decrease hospitalizations in this age group.

Major adverse cardiac event rates in moderate-risk patients: Does prior coronary disease matter?

BACKGROUND

Despite negative troponins and nonischemic electrocardiograms (ECGs), patients at moderate risk for acute coronary syndrome (ACS) are frequently admitted. The objective of this study was to describe the major adverse cardiac event (MACE) rate in moderate-risk patients and how it differs based on history of coronary artery disease (CAD).

METHODS

A secondary analysis of the HEART Pathway implementation study was conducted. This prospective interrupted time-series study accrued adults with possible ACS from three sites (November 2013-January 2016). This analysis excluded low-risk patients determined by emergency providers' HEART Pathway assessments. Non-low-risk patients were further classified as high risk, based on elevated troponin measures or ischemic ECG findings or as moderate risk, based on HEAR score ≥ 4, negative troponin measures, and a nonischemic ECG. Moderate-risk patients were then stratified by the presence or absence of prior CAD (MI, revascularization, or ≥70% coronary stenosis). MACE (death, myocardial infarction, or revascularization) at 30 days was determined from health records, insurance claims, and death index data. MACE rates were compared among groups using a chi-square test and likelihood ratios (LRs) were calculated.

RESULTS

Among 4,550 patients with HEART Pathway assessments, 24.8% (1,130/4,550) were high risk and 37.7% (1715/4550) were moderate risk. MACE at 30 days occurred in 3.1% (53/1,715; 95% confidence interval [CI] = 2.3% to 4.0%) of moderate-risk patients. Among moderate-risk patients, MACE occurred in 7.1% (36/508, 95% CI = 5.1% to 9.8%) of patients with known CAD versus 1.4% (17/1,207, 95% CI = 0.9% to 2.3%) in patients without known prior CAD (p < 0.0001). The negative LR for 30-day MACE among moderate-risk patients without prior CAD was 0.08 (95% CI = 0.05 to 0.12).

CONCLUSION

MACE rates at 30 days were low among moderate-risk patients but were significantly higher among those with prior CAD.

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.

Prehospital Translation of Chest Pain Tools (RESCUE Study): Completion Rate and Inter-rater Reliability

INTRODUCTION

Chest pain is a common reason for ambulance transport. Acute coronary syndrome (ACS) and pulmonary embolism (PE) risk assessments, such as history, electrocardiogram, age, risk factors (HEAR); Emergency Department Assessment of Chest Pain Score (EDACS); Pulmonary Embolism Rule-out Criteria (PERC); and revised Geneva score, are well validated for emergency department (ED) use but have not been translated to the prehospital setting. The objectives of this study were to evaluate the 1) prehospital completion rate and 2) inter-rater reliability of chest pain risk assessments.

METHODS

We conducted a prospective observational cohort study in two emergency medical services (EMS) agencies (April 18, 2018 - January 2, 2019). Adults with acute, non-traumatic chest pain without ST-elevation myocardial infarction or unstable vital signs were accrued. Paramedics were trained to use the HEAR, EDACS, PERC, and revised Geneva score assessments. A subset of patients (a priori goal of N = 250) also had the four risk assessments completed by their treating clinicians in the ED, who were blinded to the EMS risk assessments. Outcomes were 1) risk assessments completion rate and 2) inter-rater reliability between EMS and ED assessments. An a priori goal for completion rate was set as >75%. We computed kappa with corresponding 95% confidence intervals (CI) for each risk assessment as a measure of inter-rater reliability. Acceptable agreement was defined a priori as kappa ≥ 0.60.

RESULTS

During the study period, 837 patients with acute chest pain were accrued. The median age was 54 years, interquartile range 43-66, with 53% female and 51% Black. Completion rates for each risk assessment were above goal: the HEAR score was completed on 95.1% (796/837), EDACS on 92.0% (770/837), PERC on 89.4% (748/837), and revised Geneva score on 90.7% (759/837) of patients. We assessed agreement in a subgroup of 260 patients. The HEAR score had a kappa of 0.51 (95% CI, 0.41-0.61); EDACS was 0.60 (95% CI, 0.49-0.72); PERC was 0.71 (95% CI, 0.61-0.81); and revised Geneva score was 0.51 (95% CI, 0.39-0.62).

CONCLUSION

The completion rate of risk assessments for ACS and PE was high for prehospital field personnel. The PERC and EDACS both demonstrated acceptable agreement between paramedics and clinicians in the ED, although assessments with better agreement are likely needed.

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.

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.

Utility of COVID-19 antigen testing in the emergency department

BACKGROUND

The BinaxNOW coronavirus disease 2019 (COVID-19) Ag Card test (Abbott Diagnostics Scarborough, Inc.) is a lateral flow immunochromatographic point-of-care test for the qualitative detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleocapsid protein antigen. It provides results from nasal swabs in 15 minutes. Our purpose was to determine its sensitivity and specificity for a COVID-19 diagnosis.

METHODS

Eligible patients had symptoms of COVID-19 or suspected exposure. After consent, 2 nasal swabs were collected; 1 was tested using the Abbott RealTime SARS-CoV-2 (ie, the gold standard polymerase chain reaction test) and the second run on the BinaxNOW point of care platform by emergency department staff.

RESULTS

From July 20 to October 28, 2020, 767 patients were enrolled, of which 735 had evaluable samples. Their mean (SD) age was 46.8 (16.6) years, and 422 (57.4%) were women. A total of 623 (84.8%) patients had COVID-19 symptoms, most commonly shortness of breath (n = 404; 55.0%), cough (n = 314; 42.7%), and fever (n = 253; 34.4%). Although 460 (62.6%) had symptoms ≤7 days, the mean (SD) time since symptom onset was 8.1 (14.0) days. Positive tests occurred in 173 (23.5%) and 141 (19.2%) with the gold standard versus BinaxNOW test, respectively. Those with symptoms >2 weeks had a positive test rate roughly half of those with earlier presentations. In patients with symptoms ≤7 days, the sensitivity, specificity, and negative and positive predictive values for the BinaxNOW test were 84.6%, 98.5%, 94.9%, and 95.2%, respectively.

CONCLUSIONS

The BinaxNOW point-of-care test has good sensitivity and excellent specificity for the detection of COVID-19. We recommend using the BinasNOW for patients with symptoms up to 2 weeks.

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.

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 ethical dilemma of emergency department patients with low-risk chest pain

Millions of patients present to US EDs each year with symptoms concerning for acute coronary syndrome (ACS), but fewer than 10% are ultimately diagnosed with ACS. Well-tested and externally validated accelerated diagnostic protocols were developed to aid providers in risk stratifying patients with possible ACS and have become central components of current ED practice guidelines. Nevertheless, the fear of missing ACS continues to be a strong motivator for ED providers to pursue further testing for their patients. An ethical dilemma arises when the provider must balance the risk of ACS if the patient is discharged compared with the potential harms caused by a cardiac workup. Providers should be familiar with the ethical principles relevant to this dilemma in order to determine what is in the best interests of the patient.

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.

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.

RACE-IT - Rapid Acute Coronary Syndrome Exclusion using the Beckman Coulter Access high-sensitivity cardiac troponin I: A stepped-wedge cluster randomized trial

BACKGROUND

Protocols utilizing high-sensitivity cardiac troponin (hs-cTn) assays for the evaluation of suspected acute coronary syndrome (ACS) in the emergency department (ED) have been gaining popularity across the US and the world. These protocols more rapidly rule-out ACS and more accurately identify the presence of acute myocardial injury. At this time, few randomized trials have evaluated the safety and operational impact of these assays, resulting in limited evidence to guide the use and implementation of hs-cTn in the ED.

OBJECTIVE

The main study objective is to test the effectiveness of a rapid ACS rule-out pathway using hs-cTnI in safely discharging patients from the ED for whom clinical suspicion for ACS exists.

DESIGN

This prospective, implementation trial (n = 11,070) will utilize a stepped wedge cluster randomized trial design. The design will allow for all participating sites to capture benefit from the implementation of the hs-cTnI pathway while providing data evaluating the effectiveness in providing safe and rapid evaluation of patients with clinical suspicion for ACS.

SUMMARY

Demonstrating that clinical pathways using hs-cTnI can be effectively implemented to rapidly rule-out ACS while conserving costly hospital resources has significant implications for the care of patients with possible acute cardiac conditions in EDs across the US.

CLINICALTRIALSGOV IDENTIFIER

NCT04488913.