The original and fundamental purpose of the development of permanent pacemakers was to treat slow arrhythmias, or “slow heartbeats”. Our heart is the “engine” of the human body, and the physiological functions of the body’s organs depend on the heart to maintain the proper frequency of contraction to ensure the supply of fresh blood, just as a car engine needs to run at the right speed range. The normal heart rate is 60-100 beats per minute, if the heart rate is too low, it is called bradycardia, and the blood discharging function of the heart will be affected, just like once the engine speed is lower than idle speed, it will make the car stall and can’t be driven. Therefore, such a patient would need a permanent pacemaker. For physicians, the main criteria for determining whether a patient needs a pacemaker are “symptomatic” bradycardia, including acute bradycardia, which is a direct result of an excessively slow heart rate, resulting in decreased cardiac output and insufficient blood supply to vital organs, especially the brain, resulting in syncope, near syncope, dizziness, blackness, etc.; and This includes systemic symptoms caused by prolonged bradycardia, such as fatigue, shortness of breath after activity, and even heart failure. I will further tell you that doctors may consider recommending a permanent pacemaker if the following two conditions appear on the ECG report 1. Pathological sinus node syndrome. This is still one of the most common indications for permanent pacemaker therapy in our country. It is considered when your ECG report shows descriptions such as “sinus bradycardia, sinus arrest, sinus block”. However, the symptoms mentioned above are very important. Many people with “sinus bradycardia” and a heart rate of 40-50 beats per minute or more do not feel uncomfortable at all and their daily life is not affected, so there is no need to be overly nervous when you see bradycardia. 2.Atrioventricular block. Atrioventricular block is divided into first degree, second degree and third degree (complete) block. Mild AV block can be asymptomatic and does not require treatment, while severe and complete AV block can result in syncope due to a slow heart rate, and this type of patient requires my help to maintain life.