ST segment

The ST segment is part of an electrocardiogram (ECG) reading that shows electrical activity in the heart immediately after the heart's lower chambers (ventricles) contract. It normally appears flat and level. Changes in the ST segment, such as elevation or depression, can indicate issues like reduced blood flow to the heart muscle (ischemia) or heart damage. Healthcare providers analyze the ST segment to help diagnose conditions like heart attacks or other cardiac problems, making it an important marker in cardiac assessments.