Conduction block belongs to the category of cardiac arrhythmias and is therefore a type of heart disease. Conduction block can also be categorized into atrioventricular block, sinoatrial block, and intraventricular block according to structural differences, and first, second, and third degree block according to severity. In people, the pacemaker cells are located in the sinoatrial node, and electrical impulses are transmitted to the AV node through the interjunctional bundle conduction fibers, which conduct electrical impulses to the ventricles through the Purkinje fibers to maintain coordinated contractile motion of the heart. If the electrical impulses before the AV node cannot be transmitted to the ventricles, it is called AV block. If the electrical impulses after the AV node do not reach the end of the ventricles efficiently, it is an intraventricular block, which can be categorized as a block of the left bundle branch or the right bundle branch. When conduction block occurs, the entire heart is unable to coordinate its contractile movements, resulting in impaired heart function, inability to pump blood effectively to supply the entire body, and in severe cases, heart failure or even other organ failure. Most people with conduction block have underlying heart disease, and it is recommended to receive professional diagnosis and treatment in regular hospitals.