In pericarditis, what is likely to be observed on the electrocardiogram?

In pericarditis, the characteristic finding on an electrocardiogram (ECG) is ST segment elevation, which typically occurs in nearly all leads, particularly the limb and precordial leads, except for lead V1 in many cases. This widespread ST segment elevation reflects the inflammation and irritation of the pericardial layers surrounding the heart.

The ST segment changes in pericarditis are usually concave upward, referred to as "saddle-shaped" elevation, and are different from the elevations seen in myocardial infarction, which tend to be more pointed and localized to specific leads according to the affected area of the heart muscle.

Additionally, in pericarditis, these ST segment changes are often accompanied by other ECG findings such as PR segment depression. Over time, as the pericarditis evolves, the ST segment elevation may resolve, and instead, the ECG may show T wave inversions or normalization but the initial and prominent feature is the widespread ST segment elevation.

Other options, such as ST segment depression, normal sinus rhythm, or QT interval prolongation, are not typical findings in pericarditis. ST segment depression might indicate ischemia or other cardiac issues, normal sinus rhythm does not account for the inflammatory