Epidemiology, Classification and Description of Cardiac Arrhythmias

The term arrhythmia is used to indicate an alteration of the normal rate or regularity of the heart-beat, as well as an alteration of the physiological conduction sequence of electrical impulse from the sinus node to the His-Purkinje system and the ventricles. The term bradycardia refers to a heart rate (HR) of less than 60 beats per minute (bpm), while the term tachycardia identifies a sequence of 3 or more beats with HR above 100 bpm.