AEM Early Access 04: A 0h/1h Chest Pain Protocol

Welcome to the fourth episode of AEM Early Access, a FOAMed podcast collaboration between the Academic Emergency Medicine Journal and Brown Emergency Medicine. Each month, we'll give you digital open access to an AEM Article in Press, with an author interview podcast and links to curated FOAMed supportive educational materials for EM learners.

Find previous podcasts and suscribe to this series on iTunes here.






LISTEN NOW: Interview with Dr. Arash Mokhtari, lead author, interviewed by Dr. Michael Prucha.

Dr Arash Mokhtari, MD, PhD   Department of Internal and Emergency Medicine, Skåne University Hospital, Lund Department of Cardiology, Lund University, Skåne University Hospital, Lund

Dr Arash Mokhtari, MD, PhD

Department of Internal and Emergency Medicine, Skåne University Hospital, Lund
Department of Cardiology, Lund University, Skåne University Hospital, Lund

Open Access Through August 31st. Click here:

A 0-Hour/1-Hour Protocol for Safe, Early Discharge of Chest Pain Patients. Mokhtari A, et al. 

Article Summary:

Objective: To investigate the effectiveness of a rapid ACS rule-out protocol using 0h and 1h high-sensitivity troponin in conjunction with EKG changes and a modified TIMI risk score in order to safely and quickly discharge patients presenting with chest pain.

Methods: A secondary data analysis was performed on data collected from a prospective observational study on patients presenting to the Emergency Department at the Skåne University Hospital in Lund, Sweden. Evaluation included 0h and 1h troponin, including the absolute change, EKG changes as interpreted by Emergency physicians, as well as a modified TIMI risk score to decide whether patients could be discharged.  Adverse outcomes were defined as major adverse cardiac events (MACE) at 30 days including myocardial infarction, unstable angina, ventricular arrhythmia, atrioventricular block, cardiac arrest, or death of cardiac or unknown cause.

Results: This study included 1,020 patients who were evaluated on the above parameters, and discharged only if their modified TIMI risk score was less than, or equal to 1, the EKG was non-ischemic, and the 0h troponin was < 5 ng/L or 0 h <12 ng/L with a 1h troponin increase < 3 ng/L.  Using these criteria 432 (42.4%) patients were defined as “very low risk.”  Of those only 2 patients had MACE, both of which were unstable angina.  This produced a negative likelihood ratio of 0.04 for 30-day MACE.

Conclusion: While validation of this study needs to take place in other settings, the results of this study suggest that possibly greater than 40% of patients presenting to the ED could be discharged quickly and safely, after the result of a 1h high-sensitivity troponin or sooner, with a very small risk of missing 30-day MACE. Of course, this study was performed at one unique site in Sweden, but the results provide promising prospects for new accelerated diagnostic protocols.


Suggestions for further readinG:

Open access:

The Fast and the Furious: Low Risk Chest Pain and the Rapid Rule Out Protocol, a review, West JEM, February 2017

ERCast: Which Chest Pain Patients Can Be Discharged? February 20, 2016

REBEL EM: Management and Disposition of Low Risk Chest Pain, February 2016


Rapid Rule-out of Acute Myocardial Infarction With a Single High-Sensitivity Cardiac Troponin T Measurement Below the Limit of Detection: A Collaborative Meta-analysis. Ann Intern Med. 2017 May 16;166(10):715-724. 

Present and Future of Cardiac Troponin in Clinical Practice: A Paradigm Shift to High-Sensitivity Assays.Am J Med. 2016 Apr;129(4):354-65. 

High-sensitivity cardiac troponin assays and unstable angina.Eur Heart J Acute Cardiovasc Care. 2016 Jul 7

State-of-the-Art Evaluation of Emergency Department Patients Presenting With Potential Acute Coronary Syndromes.Hollander J et al, Circulation. 2016 Aug 16;134(7):547-64.

High-sensitivity cardiac troponin assays: answers to frequently asked questions. Arch Cardiovasc Dis. 2015 Feb;108(2):132-49


Faculty Editors/Reviewers: Dr. Kristy McAteer and Dr. Gita Pensa

Podcast credits: Used under creative commons license: intro music by , sound effect from, exit music by