Slow arrhythmia is a disease of the pacing or conduction system of the heart that causes a reduced heart rate of less than 55 beats per minute, including sinus bradycardia, sinus arrest, and severe atrioventricular block. A slow heart rate can cause insufficient blood displacement from the heart, triggering ischemia in vital organs, such as cerebral ischemia and myocardial ischemia, and setting up cardiac arrest, which is life-threatening. Such arrhythmias are often secondary to severe heart disease and should be treated with active medication for the primary cause. If medication does not improve the heart rhythm, a pacemaker should be applied to improve symptoms and prevent serious dangerous situations of cardiac and cerebral ischemia. A pacemaker can ensure a basic heart rhythm and is an important cure and life-saving method. A pacemaker can be considered in one of the following cases: Indications for pacemaker installation: 1. sinus syndrome, including fast-slow syndrome, which is difficult to treat with medication; 2. severe bradycardia, sinus block, sinus arrest, etc., accompanied by recurrent syncope; 3. atrioventricular block, including complete atrioventricular block with recurrent syncope, persistent or intermittent triple-branch block, or symptomatic atrioventricular block. Atrioventricular block, including complete AV block with recurrent syncope, continuous or intermittent three-branch block or symptomatic intraventricular block; congenital complete AV block in children; 4. After the pacemaker is installed, in order to ensure the normal operation of the pacemaker and the safety of the patient, several points should be noted: Firstly, the influence of high and low frequency electrical appliances should be avoided, because high and low frequency electrical appliances will inhibit the pacemaker from issuing pulses and cause the pacemaker to stop working. Second, prevent magnetic field interference, which can disrupt the normal work of the pacemaker. Third, protect the pacemaker skin capsule from damage and infection. The skin on the pacemaker surface is more prone to damage, necrosis and infection due to pressure, especially in elderly patients who are thin. Fourth, the correct use of household appliances, many patients are afraid to use household appliances because of the fear of using them, this is not necessary, in fact, most of the appliances will not interfere with the pacemaker, for safety reasons, the patient can keep a distance of more than 50 cm from the appliances when using them. Fifth, regular outpatient follow-up checkups, patients regularly go to the hospital for follow-up observation to test the performance and threshold of the pacemaker can ensure postoperative safety, such as monthly follow-up visits within three months after surgery, and every 3-4 months afterwards.