Which complex on an EKG indicates the relaxation of the ventricles?

The T wave on an electrocardiogram (EKG) represents the process of ventricular repolarization, which is closely associated with the relaxation of the ventricles. After the ventricles have contracted to pump blood (as indicated by the QRS complex), they need to return to a resting state, leading to relaxation. This repolarization phase, shown as the T wave, ensures that the heart can prepare for the next heartbeat.

The significance of the T wave in the cardiac cycle is critical, as it reflects the restoration of the negative membrane potential in the ventricular muscle cells, allowing them to relax and fill with blood in the diastolic phase. Understanding the timing of this process is essential for interpreting EKG readings and assessing cardiac health.

Other waves and segments on the EKG serve different functions: the P wave indicates atrial depolarization, the QRS complex reflects ventricular depolarization (contraction), and the QT interval encompasses both depolarization and repolarization phases, but it does not specifically point to the relaxation phase of the ventricles. Hence, recognizing the role of the T wave is crucial for understanding the sequence of electrical events that govern the heart's activity.