Atrial fibrillation (AF) is one of the most common arrhythmias. It is caused by many small reentry loops caused by the dominant reentry loop of the atrium. The overall incidence of AF is 0.4%. The incidence of AF increases with age and can reach 10% in people over 75 years old. During AF, the frequency of atrial excitation reaches 300-600 beats/min. The heart rate is often fast and irregular, sometimes reaching 100-160 beats/min. It is not only much faster than the heart rate of a normal person, but also absolutely irregular, and the atrium loses its effective contraction function. A large-scale survey in my country shows that the prevalence of AF is 0.77%. The prevalence of AF in men (0.9%) is higher than that in women (0.7%). The prevalence of AF in people over 80 years old is 7.5%. In addition, the increase in the prevalence of AF is closely related to the increase in diseases such as coronary heart disease, hypertension and heart failure. In the next 50 years, AF will become one of the most popular cardiovascular diseases.