Certified EKG Technician (CET) Practice Exam 2025 - Free EKG Technician Practice Questions and Study Guide

The P wave is the segment of the EKG wave that represents atrial depolarization. During this phase, the electrical impulses spread from the sinoatrial (SA) node through the atria, prompting them to contract and pump blood into the ventricles. The smooth, rounded appearance of the P wave on the EKG indicates that the atria are depolarizing in a coordinated manner.

Understanding the significance of each component of the EKG is vital for recognizing normal heart function and identifying potential abnormalities. The QRS complex, for instance, is associated with ventricular depolarization, while the T wave represents ventricular repolarization. The U wave, although less commonly seen, is related to the repolarization of the papillary muscles or other myocardial structures. Each of these waves serves a specific role in the heart's electrical activity, thus emphasizing the importance of the P wave in identifying atrial activity.