high-risk ECGSudden cardiac death accounts for almost 400,000 deaths per year in the United States, and EM providers must be adept at discerning subtle, high-risk ECG findings. With the advent of triage ECG protocols, one of the most common interruptions in the ED is a request to “sign off” on an ECG. We present a reference of some of the most important high-risk ECG findings, intended to help ED providers systematically screen patients in triage and the waiting room.

Can’t Miss ECG Findings

  1. Did you know that there are now only 2 (not 3) Brugada ECG types?
  2. Did you know that the 2013 ACCF/AHA criteria for ST elevation MI1 are different from the 2012 European Society of Cardiology (ESC)? The latter also stratifies ST elevation cutoffs for men older and younger than 40 years old, and also has more specific recommendations on right sided and posterior leads.2
  3. Have you heard of an epsilon wave?

Use this card as a checklist to methodically ensure you are not missing any electrocardiographic evidence of red-flag conditions. [Version 2, updated July 21, 2018]


ECG tracing images were obtained from various sources:

  • EKG World Encyclopedia and Wikimedia Commons [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons, courtesy of Michael Rosengarten BEng, MD.McGill
  • CardioNetworks
  • Susan Lambe, MD (UCSF Emergency Medicine)
  • James Heilman, MD (Own work) [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0) or GFDL (http://www.gnu.org/copyleft/fdl.html)] via Wikimedia Commons
  • W.G. de Voogt, MD, PhD, SLAZ, The Netherlands (W.G. de Voogt, MD, PhD, SLAZ, The Netherlands) [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons (HOCM)
  • By Npatchett (Own work) [CC BY-SA 4.0 (http://creativecommons.org/licenses/by-sa/4.0)], via Wikimedia Commons (second degree heart block)


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  2. Gowda RM, Khan IA, Wilbur SL, Vasavada BC, Sacchi TJ. Torsade de pointes: the clinical considerations. I. 2004;96(1):1-6. doi:10.1016/j.ijcard.2003.04.055
  3. Lian J, Kowey PR, Yan G-X. J Wave Syndromes. In: Management of Cardiac Arrhythmias. Humana Press; 2010:453-470. doi:10.1007/978-1-60761-161-5_21
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  12. Maron BJ, Ommen SR, Semsarian C, Spirito P, Olivotto I, Maron MS. Hypertrophic Cardiomyopathy. J. 2014;64(1):83-99. doi:10.1016/j.jacc.2014.05.003
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  14. Punukollu G, Gowda R, Vasavada B, Khan I. Role of electrocardiography in identifying right ventricular dysfunction in acute pulmonary embolism. Am J Cardiol. 2005;96(3):450-452. [PubMed]
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Christian Rose, MD

Christian Rose, MD

Clinical Informatics Fellow
Stanford University;
Emergency Physician, Kaiser Permanente
Robert Goodnough, MD

Robert Goodnough, MD

Assistant Professor, Medical Toxicology
Department of Emergency Medicine, Baylor College of Medicine