What occurs during the QRS complex of the heart rhythm?

The QRS complex in an electrocardiogram (ECG or EKG) represents the electrical activity associated with ventricular depolarization, which initiates ventricular contraction. During this phase, the ventricles (the heart's lower chambers) receive the electrical signal that causes them to contract and pump blood out to the lungs and the rest of the body.

Understanding this phase is crucial for monitoring heart health, as it indicates how well the ventricles are responding to the electrical impulses generated by the heart’s conduction system. A proper functioning QRS complex is essential for effective blood circulation, and abnormalities in this segment can indicate issues such as ventricular hypertrophy, bundle branch blocks, or other cardiac conditions.