ANATOMY

Detailed explanation-1: -The QRS complex represents the electrical impulse as it spreads through the ventricles and indicates ventricular depolarization. As with the P wave, the QRS complex starts just before ventricular contraction.

Detailed explanation-2: -The QRS complex represents the depolarization of ventricles. It shows the beginning of systole and ventricular contraction.

Detailed explanation-3: -The QRS complex is a result of ventricular depolarization and indicates the start of ventricular contraction. The T wave results from ventricular repolarization and signals the beginning of ventricular relaxation.

Detailed explanation-4: -The QRS complex of a PVC is widened, often notched, and typically has a QRS duration >0.16 seconds (waveform 1). It will have a morphology that resembles a right or left bundle branch block depending upon the location of origin, but its morphology is generally not the same as a typical bundle branch block.