At present, the causes of atrial fibrillation should be coronary heart disease and myocardial ischemia, because the population of coronary heart disease is increasing gradually. The most common cause in the past was rheumatic heart disease. In the past, economic conditions were poor and rheumatism was common. The incidence of coronary heart disease will be lower in poor economic conditions, but now the economic conditions are better, so there are more people with coronary heart disease, but there are relatively few rheumatism.