Which is the most common representation of exercise-induced myocardial ischemia?

The most common representation of exercise-induced myocardial ischemia is ST-segment depression. This phenomenon occurs when there is a lack of adequate blood flow to the heart muscle during physical exertion, leading to ischemic changes that can be observed on an electrocardiogram (ECG). When the heart is under stress, such as during exercise, the demand for oxygen increases. If the coronary arteries are narrowed or blocked, the heart muscle may not receive sufficient blood supply, which manifests as a downward deflection in the ST segment of the ECG.

ST-segment depression specifically indicates that the heart muscle is not receiving enough oxygen during the stress of exercise, and is a reliable indicator of coronary artery disease. Clinicians often utilize this finding to diagnose exercise-induced ischemia, as it directly correlates to reversibility upon cessation of exercise.

In contrast, other options present different cardiac events or changes that are less frequently associated with exercise-induced ischemia. For example, ST-segment elevation often indicates acute myocardial injury rather than ischemia during exercise. Ventricular arrhythmias can occur during exercise but are not specific markers for ischemia. QT interval prolongation relates to the timing of the cardiac cycle but is not directly indicative of ischemia. Understanding these distinctions is