On an EKG, which wave corresponds to atrial systole?

The P-wave on an electrocardiogram (EKG) represents atrial depolarization, which directly correlates with atrial systole. During this phase, the electrical impulse generated by the sinoatrial (SA) node spreads through the atria, causing them to contract and push blood into the ventricles. This contraction occurs just after the P-wave is seen on the EKG.

Understanding the role of the P-wave is crucial for interpreting cardiac function, as it reflects the time during which the atria are actively contracting. The coordinated contraction of the atria is essential for efficient filling of the ventricles before they also contract. Therefore, recognizing the significance of the P-wave as it signifies atrial systole is vital for accurate assessment when analyzing an EKG.