Disorders of heart rhythm are technically known as cardiac arrhythmia. Rhythm disorders can be irregularity in the rhythm or change in the heart rate (increase or decrease).
This animated video shows the normal conduction system of the heart. Sinus node in the upper right chamber generates the electrical pulses. The pulses are conducted down the right upper chamber to the AV Node, the second relay station. Pulses also go the left upper chamber. From the AV Node, the signal passes down to the His bundle. From the bundle of His, it passes down the left and right bundle branches into the ventricles, the lower chambers of the heart.
