Acute Coronary Occlusion Patterns

ECG Pattern and Diagnostic Considerations

• The American Heart Association and American College of Cardiology Foundation guidelines describe that occlusion between the first septal and first diagonal branches produces ST elevation in aVL with ST depression in lead III, which overlaps with the South African Flag Sign pattern but represents a different anatomic location 1, 2, 3, 4

Clinical Management Algorithm

• The American College of Cardiology recommends treating the South African Flag Sign with the same urgency as other acute occlusion patterns, and proceeding immediately to invasive coronary angiography to definitively identify the culprit lesion, as the pattern cannot reliably exclude proximal LAD or multivessel disease 1, 2, 3, 4