Cardiology Teaching Package
A Beginners Guide to Normal Heart Function, Sinus Rhythm & Common Cardiac Arrhythmias
The R Wave
The QRS complex is made up of three waves. These waves indicate the changing direction of the electrical stimulus as it passes through the heart's conduction system.
The largest wave in the QRS complex is the R wave.
Image: R Wave
As you can see from the diagram, the R wave represents the electrical stimulus as it passes through the main portion of the ventricular walls. The wall of the ventricles are very thick due to the amount of work they have to do and, consequently, more voltage is required.
This is why the R wave is by far the biggest wave generated during normal conduction.
More muscle means more cells. More cells means more electricity. More electricity leads to a bigger wave.