Which wave indicates atrial depolarization on an EKG?

The P wave indicates atrial depolarization on an EKG. This wave represents the electrical activity that causes the atria to contract, leading to the initiation of blood flow into the ventricles. When the electrical impulse generated by the sinoatrial (SA) node travels through the atrial myocardium, the resulting depolarization is recorded as the P wave on the EKG.

Understanding the role of the P wave is critical for interpreting an EKG because it is a key component of the normal cardiac cycle, reflecting the health and functioning of the atria. A deviation or abnormality in the P wave can signify various atrial conditions, such as atrial enlargement or arrhythmias, which can have significant implications for a patient's cardiac health.

In contrast, the T wave represents ventricular repolarization, the QRS complex reflects ventricular depolarization, and the U wave is often associated with repolarization effects or electrolyte imbalances, making them unrelated to atrial depolarization. Therefore, recognizing the P wave's significance is essential for effective EKG interpretation.