Whether ECG sinus bradycardia is important or not depends on whether the sinus bradycardia is physiologic or pathologic. Physiologic sinus bradycardia is normal and usually does not require treatment. Pathologic sinus bradycardia is usually secondary to other diseases and requires active treatment of the primary disease while maintaining the heart rate. 1. Physiologic bradycardia is normal. An electrocardiogram is needed, as long as it is sinus rhythm and there are no clinical symptoms, it is normal. Young people with good cardiorespiratory function, athletes, etc., will experience sinus bradycardia when they are quiet due to the strong pumping function of the heart. 2. Pathological bradycardia is generally caused by excessive vagal excitability. The vagus nerve has negative heart rate, negative conduction and negative contraction for the heart, and when the vagus nerve is over-excited, bradycardia will occur. Pathologic bradycardia is mainly seen in intracranial pressure increase, acute myocardial infarction, hypothyroidism and other diseases. The main focus is on removing the cause of the disease. Asymptomatic sinus bradycardia does not need to be treated, and regular checkups are usually sufficient. In the acute phase of symptoms, drugs such as atropine and isoprenaline can be used to elevate the heart rate, and pacemaker implantation is needed when drug treatment is ineffective or the heart rate cannot be maintained. Sinus bradycardia patients must go to the hospital for a comprehensive examination to determine the cause of the disease, and then choose the appropriate treatment plan according to the condition under the guidance of a specialist.