Dominant right coronary artery occlusion entailing diffuse ST-segment elevation in the precordial leads

Right ventricular infarction (RVI) during inferior myocardial infarction (MI) is readily diagnosed when ST-segment elevation (STE) is recorded in lead V4R. RVI may also yield precordial STE and such an electrocardiographic (ECG) pattern may be misinterpreted as a sign of anterior MI. We present a case of inferior-right ventricular (RV) MI due to occlusion of a dominant right coronary artery manifesting STE in the inferior, all precordial and right chest leads. RV dilation due to acute ischemic insult facilitated STE in leads V1-V4 despite the dominant opponent inferior and posterolateral left ventricular injury current. This case illustrates that dilation of an infarcted RV should be considered when such an ECG pattern is encountered during inferior MI, specifically a dominant one. Awareness of the circumstances under which this ECG pattern develops facilitates avoidance of misinterpretation as a sign of anterior MI and proper management.