What does the P wave represent in an EKG reading?

The P wave on an EKG reading represents atrial depolarization. This is the process that occurs when the electrical impulse generated by the sinoatrial (SA) node travels through the atria, causing them to contract and push blood into the ventricles. The P wave signifies the beginning of the cardiac cycle, where the atria fill with blood and then contract, ensuring efficient blood flow into the ventricles ahead of the subsequent ventricular contraction.

Understanding the P wave's role is crucial for interpreting EKGs accurately. It helps healthcare professionals assess atrial function and identify potential issues such as atrial enlargement or arrhythmias. When analyzing an EKG, recognizing the P wave's characteristics—such as its shape, duration, and amplitude—plays a significant role in diagnosing various cardiac conditions.