QRS complex

The QRS complex is a part of an electrocardiogram (ECG) that represents the electrical activity when your heart's ventricles (the main pumping chambers) contract to push blood out to your body. It appears as a series of peaks—Q, R, and S waves—that reflect the rapid electrical changes during this contraction. A normal QRS complex indicates the ventricles are contracting properly, while abnormalities can suggest issues like irregular rhythms or conduction problems. It's a vital marker used by healthcare providers to assess heart health and rhythm.