In an EKG, what does the P wave represent?

The P wave in an electrocardiogram (EKG) represents atrial contraction, specifically the depolarization of the atria. This electrical activity occurs when the sinoatrial (SA) node stimulates the atrial muscles, causing them to contract and push blood into the ventricles. The size and shape of the P wave can give information about atrial health and function, allowing healthcare providers to assess if the atria are functioning normally.

Understanding the significance of the P wave is crucial for interpreting an EKG. When examining the cardiac cycle, it’s important to recognize that the P wave precedes the QRS complex, which represents ventricular depolarization and contraction. This relationship is integral in assessing the timing and coordination of the heart's electrical activity. The presence, shape, and duration of the P wave can indicate atrial enlargement or other abnormalities, making it a key feature in diagnosing various cardiac conditions.