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Andrew Grock, MD; Manuel Celedon, MD; and Jonie Hsiao, MD

​​It was with great interest that we read Most Clinicians Are Still Not Comfortable Sending Chest Pain Patients Home with a Very Low Risk of 30-day Major Adverse Cardiac Event (MACE) by Dr. Michael Weinstock, et al in the February 2021 issue of JUCM.1

In this study, the authors surveyed attendants at an emergency medicine conference in 2018 as to their comfort level discharging patients after a negative acute coronary syndrome (ACS) work-up.1 The survey cohort consisted mostly of United States and Canadian attending physicians, residents, or midlevel providers. Later that year, the American College of Emergency Physicians (ACEP) published national guidelines recommending an acceptable 30-day MACE rate of 1%-2%.2 However, survey respondents reported much more conservative views, with almost 50% reporting an acceptable level of missed 30-day MACE of 0.1% or 0.01%. In fact, less than 1/3 of participants met ACEP’s recommended 1%-2% miss rate.2

Though the authors address potential changes in responses due to these newer guidelines, we feel the need to address the possible root causes of these very conservative responses.

Firstly, the word “missed” implies an attribution of fault to the treating provider; and what provider would willingly admit to being comfortable “missing” a critical diagnosis? This wording, which brings to mind fear of litigation and a poor patient outcome, may begin to explain the conservative views of the study participants.

Secondly, comfort level does not necessarily correspond to actual provider practice. A provider’s comfort level discharging a low-risk chest pain patient is multifactorial, including factors such as poor follow-up and coexisting conditions.3 In fact, the American Heart Association first recommended discharging low-risk patients after a negative ED ACS work-up 8 years prior to the survey, which makes it difficult to believe that the surveyed providers continue to admit patients at a 0.1% rate of 30-day MACE.4

Most importantly, equating missed MACE and missed ACS is somewhat confounding. MACE often includes percutaneous coronary intervention and coronary artery bypass graft surgery, which may be appropriately offered to patients without ACS to treat (for example, stable angina). Experts have argued that 30-day MACE is in fact a poor marker to determine ED disposition. Weinstock, et al proposed using clinically relevant adverse cardiac events (CRACE) such as rate of in-hospital life-threatening arrhythmia, ST-segment–elevation MI, cardiac or respiratory arrest, or death to describe a more clinically relevant outcome.5 The time after which the “missed” CRACE is attributed to the index provider may require adjustment to a more ED-centric endpoint such as the 15 day endpoint recently proposed by Green and Schriger.6

The next question posed by this research is: What to do with low-risk patients after a negative ACS work-up? Hospitalization carries known risks such as medical error and delirium.7,8 Yet, a benefit to admitting patients after a negative ACS work-up in the ED has yet to be demonstrated. Previously, admission afforded a chance to catch potential “missed” ACS, perform provocative testing, and optimize medical management. Current data suggest a drastically different picture. With the implementation of the high-sensitivity troponin, the rate of unstable angina has decreased and may potentially be a disease of the past.9-11 In fact, 18% to 30% of patients previously classified as having unstable angina would now be defined as NSTEMIs.12

One large study on patients hospitalized for possible ACS after two negative troponins, two nonischemic electrocardiograms, and normal vital signs in the ED demonstrated a 0.06% (95% CI, 0.02%-0.14%) rate of inpatient complications (a STEMI, cardiac or respiratory arrest, or death).5 Of these four patients, two were noncardiac, and two were possibly iatrogenic.5 Additionally, provocative testing in low-risk populations results in no mortality benefit or decrease in ACS rates. Instead, it only serves to increase the rate of cardiac catheterizations, which carries its own rate of complications.2,13-16 Optimal medical management theoretically could improve 4-week rates of MACE, but does not require hospitalization to perform. As Weinstock, et al previously posited, “does an increased risk of MACE at 4–6 weeks justify immediate hospitalization or emergent intervention?”5

While we are all trying to do the best we can for our patients, it’s important to recognize the limitations and risks of hospitalization in weighing the appropriate disposition. In discussing these risks with patients, it does appear that they seem to be significantly less risk-averse than doctors when engaged with shared medical-decision making.17-19

The testing and data for diagnosing and dispositioning possible ACS patients has drastically changed in the past 10 years. Currently, the best available evidence supports discharging low-risk patients after a negative ACS work-up and a 4-week risk of MACE at 1%-2%.20-23 Additionally, multiple national and international organizations have recommended discharge of these patients, and there is no demonstrated benefit to admission.2, 24

All that’s left is to get our fellow physicians and providers comfortable with these new recommendations.


  1. Weinstock MB, Pallaci M, Mattu A, et al. Most clinicians are still not comfortable sending chest pain patients home with a very low risk of 30-day major adverse cardiac event (MACE). J Urgent Care Med. 2021;15(5):17-21.
  2. American College of Emergency Physicians Clinical Policies Subcommittee (Writing Committee) on Suspected Non–ST-Elevation Acute Coronary Syndromes, Tomaszewski CA, Nestler D, Shah KH, et al. Clinical policy: critical issues in the evaluation and management of emergency department patients with suspected non-ST-elevation acute coronary syndromes. Ann Emerg Med. 2018;72(5):e65-e106.
  3. Pena M, Tsao J, Falaiye T, et al. Why won’t emergency physicians discharge patients with a low HEART score from an observation unit without further evaluation? Crit Pathw Cardiol. 2020;19(4):195-199.
  4. Amsterdam E, Wenger N, Brindis R, et al. 2014 AHA/ACC guideline for the management of patients with non-ST-elevation acute coronary syndromes: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. Circulation. 2014;130(25):e344-426.
  5. Weinstock MB, Weingart S, Orth F, et al. Risk for clinically relevant adverse cardiac events in patients with chest pain at hospital admission. JAMA Intern Med. 2015;175(7):1207-1212.
  6. Green SM, Schriger DL. A methodological appraisal of the HEART score and its variants. Ann Emerg Med. 202178(2):253-266.
  7. Makary MA, Daniel M. Medical error—the third leading cause of death in the US. BMJ. 2016;353:i2139.
  8. Holroyd-Leduc JM, Khandwala F, Sink KM. How can delirium best be prevented and managed in older patients in hospital? CMAJ. 2010;182(5):465-70.
  9. Neumann JT, Sorensen NA, Rubsamen N, et al. Evaluation of a new ultra-sensitivity troponin I assay in patients with suspected myocardial infarction. Int J Cardiol. 2019;283:35-40.
  10. Thygesen K, Alpert JS, Jaffe AS, et al; Executive Group on behalf of the Joint European Society of Cardiology (ESC)/American College of Cardiology (ACC)/American Heart Association (AHA)/World Heart Federation (WHF) Task Force for the Universal Definition of Myocardial Infarction. Fourth Universal Definition of Myocardial Infarction (2018). J Am Coll Cardiol. 2018;72(18):2231-2264.
  11. Braunwald E, Morrow DA. Unstable angina: is it time for a requiem? Circulation. 2013;127(24):2452-2457.
  12. Sandoval Y, Apple FS, Smith SW. High-sensitivity cardiac troponin assays and unstable angina. Eur Heart J Acute Cardiovasc Care. 2018;7:120–128.
  13. Poon M, Cortegiano M, Abramowicz A, et al. Associations between routine coronary computed tomographic angiography and reduced unnecessary hospital admissions, length of stay, recidivism rates, and invasive coronary angiography in the emergency department triage of chest pain. J Am Coll Cardiol. 2013;62(6):543-552.
  14. Frisoli T, Nowak R, Evans K, et al. Henry Ford HEART score randomized trial: rapid discharge of patients evaluated for possible myocardial infarction. Circ Cardiovasc Qual Outcomes. 2017;10(10):e003617.
  15. Sandhu A, Heidenreich P, Bhattacharya J, Bundorf M. Cardiovascular testing and clinical outcomes in emergency department patients with chest pain. JAMA Intern Med. 2017;177(8):1175-1182.
  16. Foy A, Liu G, Davidson W, et al. Comparative effectiveness of diagnostic testing strategies in emergency department patients with chest pain: an analysis of downstream testing, interventions, and outcomes. JAMA Intern Med. 2015;175(3):428-436.
  17. Hess EP, Grudzen CR, Thomson R, et al. Shared decision-making in the emergency department: respecting patient autonomy when seconds count. Acad Emerg Med. 2015;22(7):856-864.
  18. Hess EP, Hollander JE, Schaffer JT, et al. Shared decision making in patients with low risk chest pain: prospective randomized pragmatic trial. BMJ. 2016;355:i6165.
  19. Hess EP, Knoedler MA, Shah ND, et al. The chest pain choice decision aid: a randomized trial. Circ Cardiovasc Qual Outcomes. 2012;5(3):251-259.
  20. Chapman AR, Hesse K, Andrews J, et al. High-sensitivity cardiac troponin i and clinical risk scores in patients with suspected acute coronary syndrome. Circulation. 2018;138(16):1654-1665.
  21. Poldervaart JM, Langedijk M, Dekker BE, et al. Comparison of the GRACE, HEART and TIMI score to predict MACE in CP pt’s at the ED. Int J Cardiol. 2017;227:656-661.
  22. Mark DG, Huang J, Chettipally U, et al. Kaiser Permanente CREST Network Investigators. Performance of coronary risk scores among pts w/ CP in the ED. J Am Coll Cardiol. 2018;71(6):606-616.
  23. Body R, Morris N, Reynard C, Collinson PO. Comparison of four decision aids for the early diagnosis of acute coronary syndromes in the emergency department. Emerg Med J. 2020;37(1):8-13.
  24. Collette J-P, Thiel H, Barbato E, et al, ESC Scientific Document Group. 2020 ESC Guidelines for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation: The Task Force for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation of the European Society of Cardiology (ESC). Eur Heart J. 2021;42(14):1289-1367.
Counterpoint: Readers React to JUCM Original Research

Andrew Grock, MD

HS Assistant Clinical Professor of Emergency Medicine

Jonie Hsiao, MD

HS Assistant Clinical Professor of Emergency Medicine

Manuel Celedon, MD

practices Emergency Medicine at the Greater Los Angeles VA and Harbor-UCLA hospitals
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