ST Elevations in V2-V4: Pericarditis vs. Myocardial Infarction

Critical Distinguishing Features

• The American College of Cardiology recommends that ST elevations in leads V2, V3, and V4 can still represent pericarditis, but you must actively exclude anterior STEMI caused by left anterior descending (LAD) artery occlusion, which carries significantly higher mortality risk and requires immediate reperfusion therapy 1, 2
• The American College of Cardiology and Circulation suggest that absence of reciprocal ST depression in leads opposite to the ST elevation, particularly no depression in inferior leads II, III, aVF when V2-V4 are elevated, suggests pericarditis rather than LAD occlusion 1, 3
• Convex (upward) ST elevation with reciprocal ST depression in inferior leads (II, III, aVF) indicates LAD occlusion, according to the American College of Cardiology and Circulation 1, 3
• ST elevation in V1 through V4-V6 PLUS elevation in leads I and aVL with reciprocal depression in II, III, aVF indicates proximal LAD occlusion above the first septal and diagonal branches, requiring emergent catheterization, as stated by Circulation 3, 4

Algorithmic Diagnostic Approach

• If ST elevation is isolated to V2-V4 only without involvement of V1, I, or aVL, and without reciprocal changes, consider more distal LAD occlusion or pericarditis, according to Circulation 3, 4
• If ST elevation extends to V1, I, and aVL with reciprocal depression in II, III, aVF, this is proximal LAD occlusion, and the American College of Cardiology recommends activating the catheterization lab immediately 3, 4

Common Pitfalls to Avoid

• The American College of Cardiology emphasizes that pericarditis should be considered in the differential when evaluating ST elevation, and that ST deviation in pericarditis should not be dismissed as a "false positive" ECG pitfall 1, 5, 6
• The American College of Cardiology and Circulation note that right bundle branch block causes ST-T abnormalities in V1-V3, making ischemia assessment difficult in these leads, but new ST elevation or Q waves should still raise concern for myocardial ischemia or infarction 2, 5, 7