Combined ST Elevation in a Case of Acute Myocardial Infarction: How to Identify the Infarct-related Artery?

Combined ST elevation in anterior and inferior ECG leads in acute myocardial infarction is not a rarity. It is both interesting and challenging to indentify the infarct related culprit artery. We report the case of a middle aged male with acute myocardial infarction whose admission ECG shows ST elevation in lead II, III, aVF as well as from V-V. 90% of such cases are due to single vessel occlusion - majority due to proximal RCA occlusion and the remaining due to mid to distal LAD occlusion. ECG features to differentiate between these two vascular occlusions are discussed. In this case at hand, lead III ST elevation of 2.5 mm and V/V≥ 1 indicates proximal RCA as the IRA and the same has been confirmed by pre-discharge coronary angiogram .