Rosh Emergency Medicine Practice Test

What characteristic ECG finding is associated with pericarditis?

1. A. ST segment depression

2. B. Q wave formation

3. C. Diffuse ST elevation

4. D. T wave inversion

The correct answer is: C. Diffuse ST elevation

Diffuse ST elevation is a key characteristic ECG finding associated with pericarditis. In this condition, the ST segments are elevated in multiple leads, commonly seen in leads I, II, III, aVL, aVF, and V2 to V6. This elevation is typically concave in shape and can be recognized as a widespread pattern rather than a localized change, which is distinct from findings observed in other cardiac conditions such as myocardial infarction. In pericarditis, these ST elevations reflect inflammation of the pericardial sac rather than ischemia, which helps in differentiating it from other causes of ST elevation on an ECG. Additionally, the absence of reciprocal ST segment depression, which is common in myocardial infarction, supports the diagnosis of pericarditis when diffuse ST elevation is present. Other choices, such as ST segment depression, Q wave formation, and T wave inversion, are usually associated with different cardiac pathologies. For example, ST segment depression commonly indicates myocardial ischemia, Q waves can suggest a prior myocardial infarction, and T wave inversion may signify ischemia or other cardiac conditions. Therefore, the presence of diffuse ST elevation specifically guides clinicians towards considering pericarditis as the underlying issue.