ACLS/BLS Preparation

ST Segment

The ST Segment lies between the J point, and the start of the T wave.

The baseline is a flat spot on the ECG between the T and P wave devoid of depolarization or repolarization waves.

The ST Segment's positive or negative shift from the baseline is measured, rather than ita width as in other ECG components.

Any positive or negative ST segment shift, above or below, the baseline can indicate a problem.