Atrial fibrillation most commonly occurs in patients with organic heart disease, such as rheumatic heart disease, coronary atherosclerotic heart disease, hypertensive heart disease, cardiomyopathy, constrictive pericarditis, and chronic pulmonary heart disease, etc. It can also be seen in diseases of other systems such as hyperthyroidism, etc. In addition, as age increases, the incidence of atrial fibrillation also increases. Some causes of atrial fibrillation are unknown and may be triggered by emotional stress, physical activity, or heavy drinking. For atrial fibrillation, once an episode occurs, it is important to actively administer appropriate medications to control it, to avoid the adverse consequences of persistent atrial fibrillation.