There are two major types of arrhythmias, including abnormalities of origin and abnormalities of conduction. Which arrhythmias are caused by conduction abnormalities? These are mainly seen in conduction block, such as atrioventricular block, sinus block, and intraventricular block, which are all abnormalities of agitated conduction. There are many other cases, such as the most common supraventricular tachycardia, which is also an excitatory conduction abnormality, and it is likely that there is a double pathway with a bypass to cause this conduction abnormality. Therefore, the kind of arrhythmia that occurs is related to the anatomy and mechanism of the heart, so abnormal conduction of the heart rate is very common and requires intracardiac electrophysiological examination to make a clear diagnosis, and some cases can be clearly diagnosed by electrocardiogram.