Which electrocardiographic finding is most characteristic of acute pericarditis?

Which electrocardiographic finding is most characteristic of acute pericarditis?

• A. Diffuse ST-segment elevation
• B. ST-segment depression in inferior leads
• C. Q waves
• D. T wave inversion in aVR

Answer: (A)

Acute pericarditis inflames the pericardial sac, creating injury currents that affect many areas of the heart at once. The result on the ECG is diffuse, widespread ST-segment elevation that is usually concave upward across multiple leads, often accompanied by PR-segment depression. This pattern reflects the global irritation of the pericardium, rather than localized myocardial injury. In contrast, ST-segment depression in inferior leads would point toward ischemia in a specific coronary territory, not a global pericardial process. Q waves indicate prior myocardial infarction with scar, not an acute inflammatory process. T wave inversion in aVR is not a defining feature of acute pericarditis and can occur in various other conditions.

Acute pericarditis inflames the pericardial sac, creating injury currents that affect many areas of the heart at once. The result on the ECG is diffuse, widespread ST-segment elevation that is usually concave upward across multiple leads, often accompanied by PR-segment depression. This pattern reflects the global irritation of the pericardium, rather than localized myocardial injury.

In contrast, ST-segment depression in inferior leads would point toward ischemia in a specific coronary territory, not a global pericardial process. Q waves indicate prior myocardial infarction with scar, not an acute inflammatory process. T wave inversion in aVR is not a defining feature of acute pericarditis and can occur in various other conditions.