Which wave on an ECG represents ventricular repolarization?

The T wave on an ECG represents ventricular repolarization, which is a critical phase in the cardiac cycle. During this phase, the ventricles recover from the electrical activity that triggered their contraction (ventricular depolarization, represented by the QRS complex).

Repolarization involves the return of the heart muscle cells to their resting state, where they prepare for the next heartbeat. This process is vital for the effective functioning of the heart as it ensures the muscle cells are ready to contract again when the next electrical impulse occurs. The T wave appears as a positive deflection following the QRS complex on the ECG strip, making it visually distinct and easy to identify.

The other waves on the ECG represent different phases of the cardiac cycle. The P wave indicates atrial depolarization, the QRS complex signifies ventricular depolarization, and the U wave, which can sometimes be seen, is thought to represent the repolarization of the Purkinje fibers or late ventricular repolarization, but is less commonly associated with the ventricular repolarization as specifically as the T wave is. Understanding these different components is crucial for interpreting an ECG correctly in any clinical setting.