What does the T-wave in an ECG represent?

The T-wave in an ECG represents ventricular repolarization, which is a critical phase in the cardiac cycle. During this phase, the ventricles, which are the heart's lower chambers, restore their electrical state following contraction. This repolarization process allows the heart muscle to return to its resting state, preparing for the next contraction cycle.

Understanding the T-wave's role is essential for interpreting cardiac electrical activity accurately. It reflects the electrical activity as the ventricles recover and is crucial for ensuring the heart can continue to function effectively. The morphology and duration of the T-wave can provide valuable insights into cardiac health and potential electrolyte imbalances or ischemic conditions.

The other options pertain to different electrical activities of the heart: atrial depolarization is represented by the P wave, ventricular depolarization is indicated by the QRS complex, and atrial repolarization is typically not prominently visible in the standard ECG. Recognizing these distinctions further emphasizes the significance of the T-wave in relation to the overall cardiac cycle.