What ECG change is typically observed in patients with ischemic heart disease?

In patients with ischemic heart disease, the typical ECG change observed is ST segment depression. This change signifies that there is a lack of blood flow and oxygen to part of the heart muscle during periods of stress or physical activity (such as during exertion or exercise) or even at rest in more advanced cases. This signals myocardial ischemia, which occurs when the heart muscle does not receive adequate blood supply due to narrowed arteries.

The presence of ST segment depression can indicate a problem with the coronary arteries and suggests that the myocardial tissue is being affected by insufficient perfusion. It is important for health professionals to recognize ST depression on an ECG, as it can be an indicator of underlying coronary artery disease and can prompt further evaluation and management to prevent significant cardiac events.