What does a U wave typically represent on an EKG?

The U wave on an EKG typically represents the repolarization of the Purkinje fibers, which are specialized conductive fibers in the heart that help coordinate its electrical activity. While the U wave is often subtle and not always present in every EKG tracing, when it is observed, it can provide important information about the heart's repolarization processes.

This wave follows the T wave, which represents the repolarization of the ventricles. The U wave may arise due to the delayed repolarization of the Purkinje fibers and the ventricular myocardium. Understanding the role of the U wave is significant in clinical practice, as it can sometimes indicate underlying conditions when it appears prominent or abnormal, but its primary association is with the repolarization of the Purkinje fibers.

In contrast, the other concepts listed do not directly correspond to the U wave. Atria depolarization is represented by the P wave, conduction delay affects the timing and intervals in the EKG tracing but is not attributed to the U wave, and while the presence of U waves can sometimes relate to arrhythmias, it is not their primary representation. Overall, recognizing what the U wave signifies can aid in interpreting EKGs and assessing cardiac health.