What is a common cause of ST segment depression?

ST segment depression is commonly associated with myocardial ischemia, which occurs when there is a reduced blood flow to the heart muscle, often due to narrowed or blocked coronary arteries. This reduction in blood flow can result in inadequate oxygen delivery to the myocardial cells during physical exertion or stress, leading to changes in the heart's electrical activity, as seen on the EKG.

When myocardial ischemia occurs, the T wave may become flat or inverted, and the ST segment often shows a downward slope relative to the baseline, indicating that the heart muscle is not receiving enough oxygen. This finding is crucial in diagnosing conditions such as angina and helps healthcare providers assess the severity of coronary artery disease. Recognizing ST segment depression allows for timely intervention to restore adequate blood flow and prevent further cardiac complications.

In contrast, other options like myocardial infarction may cause ST segment elevation rather than depression, while hypertension typically does not result directly in ST segment changes unless there is accompanying ischemia. Atrial fibrillation primarily affects heart rhythm rather than causing changes specifically in the ST segment.