Background: Patients with chest pain who have ST elevations on electrocardiogram (ECG) are at high risk for ST-elevation myocardial infarction (STEMI). Recent literature has reported various STEMI equivalents, which may be equally threatening. One STEMI equivalent, previously named the de Winter pattern, describes ECG changes where there are ST-segment depressions in the precordial leads in association with tall, symmetrical, hyperacute T-waves. These changes have been connected with proximal left anterior descending coronary artery occlusion., Case Report: We have identified a case of the de Winter ECG pattern immediately after ventricular fibrillation cardiac arrest. A 33-year-old man presented with waxing and waning severe substernal chest pain. The patient was on no prior medications, and had no risk factors for acute coronary syndrome. The initial ECG showed ST depression, which was followed by normalization in a repeat ECG only minutes later. The patient then developed ventricular fibrillation cardiac arrest. After defibrillation, return of spontaneous circulation was achieved and subsequent ECGs demonstrated the de Winter ECG pattern. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: The characteristic ECG changes within the de Winter ECG pattern may be missed or misdiagnosed as nonspecific, reversible ischemia. This can significantly lengthen the transportation to a center equipped with a percutaneous coronary intervention laboratory, and thus the start of reperfusion therapy. It is imperative that all practitioners learn to identify this novel ECG pattern as a STEMI equivalent to ensure appropriate intervention in the cardiac catheterization laboratory., (Copyright © 2016 Elsevier Inc. All rights reserved.)