What is represented by the P wave, QRS complex, and T wave?

The P wave, QRS complex, and T wave collectively represent the cardiac cycle in an electrocardiogram (EKG or ECG). The cardiac cycle encompasses all the events that occur during one heartbeat, including the electrical activity that initiates and coordinates the heart's contractions.

The P wave reflects atrial depolarization, indicating that the atria are contracting and pumping blood into the ventricles. The QRS complex represents ventricular depolarization, which signals the contraction of the ventricles to eject blood to the lungs and the rest of the body. Lastly, the T wave denotes ventricular repolarization, representing the recovery phase of the ventricles after contraction, preparing them for the next heartbeat.

This sequence of waves allows healthcare professionals to assess the electrical activity of the heart, ensuring proper function and identifying any abnormalities in the cardiac cycle. Thus, understanding these components is crucial for interpreting EKG results effectively.