What does the P wave of the electrocardiogram (EKG) represent?

The P wave of the electrocardiogram (EKG) specifically represents atrial depolarization. This event occurs when the electrical impulse generated by the sinoatrial node travels through the atria, causing them to contract and pump blood into the ventricles. This depolarization is visually depicted on the EKG as the first small upward deflection following the baseline.

Understanding the significance of the P wave is crucial for interpreting the EKG and assessing the heart's electrical activity. Atrial depolarization is the first step in the cycle of cardiac electrical conduction, initiating the process that leads to the subsequent contraction of the ventricles. This sequence is vital for maintaining proper blood circulation in the body.