What does ST segment elevation indicate?

ST segment elevation is a significant finding in an electrocardiogram (ECG or EKG) that typically indicates the presence of myocardial infarction, often referred to as a heart attack. During a myocardial infarction, blood supply to a portion of the heart muscle is blocked, leading to damage. This condition can cause the heart muscle to become distressed and can result in altered electrical activity, which manifests as ST segment elevation on an ECG.

In the context of myocardial infarction, the ST segment elevation indicates that the heart muscle is undergoing significant stress, and this can be a marker of acute coronary occlusion. Clinicians often look for ST segment elevation in specific leads to identify the location of the myocardial damage, which is crucial for treatment decisions.

While ST segment changes can indicate other cardiac conditions, such as ischemia, heart failure, or heart block, it is the elevation that is most specifically associated with the acute phase of myocardial infarction. Ischemia can lead to other types of ST segment changes, such as depression, but ST segment elevation directly points towards immediate and severe myocardial injury.