In the context of heart disease, what does ST segment depression typically indicate?

ST segment depression on an electrocardiogram (ECG) is most commonly associated with potential myocardial ischemia. This phenomenon occurs when there is a decrease in blood flow to the heart muscle, usually due to an obstructed coronary artery or increased myocardial oxygen demand that exceeds supply. When the heart is not receiving enough oxygen-rich blood, it can lead to changes in the electrical activity of the heart, which manifests as an ST segment depression.

This is an important finding, as it can help healthcare professionals assess the presence and severity of coronary artery disease and can indicate the need for further investigation or intervention, such as stress testing or imaging studies. Recognizing ST segment depression allows clinicians to make informed decisions regarding a patient’s management plan, particularly in the context of angina or acute coronary syndromes.

In contrast, normal cardiac activity would typically show an isoelectric ST segment without these depressions, while heart valve incompetence and reduced ejection fraction relate to structural and functional heart issues rather than the immediate assessment of myocardial ischemia evident through ST segment changes.