What is an arrhythmia?

An arrhythmia is an irregular heartbeat that often results from a change or malfunction in the heart's conduction system. The conduction system is where normal electrical activity travels where normal electrical impulses travel through the heart. An arrhythmia can occur when the heart's natural pacemaker develops an abnormal rate, the normal conduction pathway is interrupted, or another part of the heart takes over as pacemaker. Arrhythmias can be unusually fast, called tachycardia, or unusually slow, called bradycardia.