One way to look at it is from the point of view of how we, the people, feel about the heartbeat, i.e. how it behaves: any disease related to the rhythm or frequency of the heartbeat can be called an arrhythmia. For example, a heartbeat that is too fast, too slow, or that comes and goes, as well as an irregular heartbeat. Some people have arrhythmias that are persistent, others have a normal heartbeat most of the time with occasional cardiac arrests; or very long periods of stopping at night, all of which occur as arrhythmias. Another medical point of view, i.e. the mechanism of arrhythmia: the command of our normal heart to send out excitation is called sinus node, and the command from it is called sinus rhythm, which is a normal heart rhythm. When the heart excitation is not sent out from sinus node, but other places such as atrium, ventricle or atrioventricular node junction, it is called abnormal excitation arrhythmia. The normal conduction of heart excitation is along the heart’s inherent conduction pathway in the order of atrium, atrioventricular node, and ventricle, which eventually excites the whole heart. If the order, speed, and pathway of heart excitation change in the process of conduction, it is called arrhythmia. Now the people have a certain awareness of heart ischemia, coronary heart disease myocardial infarction, to the hospital can receive imaging, and even stents, but little awareness of arrhythmias, think that this is some of the “minor diseases” that do not affect life, do not affect health, do not affect life. In fact, most arrhythmias need to be treated, which may sound very advanced to you, but we will tell you about it slowly.