What does the T wave represent in an EKG tracing?

The T wave in an EKG tracing represents ventricular repolarization. This is the phase in the cardiac cycle when the ventricles, having contracted to pump blood, are returning to their resting state. The repolarization process involves the return of the cardiac muscle cells to their resting electrical state, which is essential for them to be ready for the next contraction.

During the T wave, there is a shift in the electrical activity of the ventricles rather than any electrical activity in the atria, such as depolarization or contraction, making this T wave representation critical for assessing the recovery phase of the ventricles after they have discharged their electrical impulse and contracted. Recognizing this aspect of the T wave aids in diagnosing various cardiac conditions, including arrhythmias and ischemic heart disease.