What is indicated by a consistently elevated ST segment on an EKG?

A consistently elevated ST segment on an EKG is indicative of myocardial infarction, particularly in the context of ST-elevation myocardial infarction (STEMI). In this condition, there is a significant and prolonged elevation of the ST segment, which reflects the ongoing necrosis of myocardial tissue due to insufficient blood flow, typically caused by a blockage in a coronary artery.

In the early stages of a myocardial infarction, the ST segment elevation appears as a result of injury to the myocardial cells. This injury disrupts the normal polarization of the heart muscle, leading to changes in the electrical activity that can be seen on the EKG. Persistent ST segment elevation suggests that the heart muscle is still at risk and that there is likely a significant obstruction preventing adequate blood supply.

In contrast, the other conditions mentioned do not typically present with consistently elevated ST segments:

• Arrhythmias can affect the heart's rhythm but do not specifically cause ST segment elevation.

• Myocardial ischemia, which generally refers to a temporary decrease in blood flow, often presents as ST segment depression rather than elevation.

• Normal variants may occur in some individuals but do not result in constant elevation of the ST segment to the extent observed in myocardial infarction.

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