What does the P wave on an EKG represent?

The P wave on an EKG represents atrial depolarization. During this phase, the electrical impulse originating from the sinoatrial (SA) node spreads through the atria, causing them to contract and pump blood into the ventricles. This depolarization is critical for initiating the heart's rhythm, as it precedes the contraction of the atria and sets the stage for subsequent events in the cardiac cycle.

Understanding the components of an EKG is essential for interpreting heart activity correctly. The P wave's specific association with atrial depolarization is foundational for grasping how the heart conducts electrical signals and coordinates its contractions. Recognizing this waveform allows healthcare providers to assess the function of the atria and the overall rhythm of the heart.