A proximal right coronary artery occlusion presenting with ST-segment depression in leads II, III, and aVF

The first electrocardiogram (ECG) finding during myocardial ischemia is the deviation of the ST-segment. The overall ST vector is usually shifted in the direction of the ischemic zone that can be localized by the 12-lead ECG. However, in some cases, it is subject to limitations and exceptions (1). We present a patient with ST-segment elevation in leads aVR and V1 with diffuse STsegment depression in other extremity leads whose right coronary artery (RCA) was occluded. The present case signifies that ECG could be limited in determining the infarct-related artery by individual variations in coronary anatomy and the presence of pre-existing conditions as collateral circulation.