Cardio| Localization of MI on ECG

1.10 Localization of MI on ECG Cardiovascular system review for the USMLE Step 1 exam T Myocardial infarction (MI) can be localized by identifying changes in various ECG leads Anterior STEMI: ST elevation in precordial leads V3, V4, indicating occlusion of the distal left anterior descending artery (LAD) Lateral MI: ST elevation in leads I, aVL, aVR, and precordial leads V5, V6, caused by an occlusion of the LAD Septal MI: ST elevation in leads V1, V2, V3, caused by an occlusion to the LAD Inferior MI: ST elevation in leads II, III, aVF, caused by an occlusion of the right coronary artery (RCA) Posterior MI: ST elevation in V7, V8, V9, caused by an occlusion of the posterior descending artery (PDA)