Which component of the ECG corresponds to ventricular depolarization?

The QRS complex of the ECG corresponds to ventricular depolarization, which is a critical phase in the cardiac cycle. During this phase, the electrical activation spreads through the ventricles, leading to their contraction and the subsequent pumping of blood to the lungs and the rest of the body. The QRS complex represents the combined electrical activity of the left and right ventricles as they depolarize, and it typically appears as a sharp, tall spike on the ECG tracing.

In contrast, the P wave represents atrial depolarization, which occurs before the ventricles contract. The T wave denotes ventricular repolarization, signaling the recovery phase after the ventricles have contracted. The QT interval encompasses both depolarization and repolarization of the ventricles but does not specifically represent just the depolarization phase. Understanding these components is essential for interpreting ECG readings and assessing heart function accurately.