Two patients with rheumatic heart valve disease combined with persistent atrial fibrillation underwent mitral valve replacement and left atrial thrombus extraction, and at the same time, radiofrequency ablation was applied to eliminate atrial fibrillation under direct visualization with modified maze surgery. After the operation, the patients recovered quickly and were discharged from the hospital with normal sinus rhythm. One patient has been followed up for 7 months without any antiarrhythmic drugs, the atrial fibrillation disappeared and has been in normal sinus rhythm with good cardiac function, the first independently accomplished and successful case. The incidence of atrial fibrillation (AF) in middle-aged and elderly people is increasing year by year. According to the latest statistics, the incidence of AF in the elderly population over 60 years old is 10%, and the fatality rate is second only to that of ventricular fibrillation. The overall mortality rate is twice as high as that of patients without AF. AF is highly susceptible to atrial thrombosis, and thrombus dislodgement can lead to infarction of the brain, heart, kidney and other important organs. The incidence of stroke is five times higher in patients with AF than in those without AF, and is 7-20 times higher in patients with heart valve disease. It is an important cause of death and disability in middle-aged and elderly people. Chronic persistent AF is poorly treated with medication, interventional therapy has a low success rate and a high likelihood of frequent recurrences, and previous valve surgery alone could not eliminate atrial fibrillation. The traditional surgical method is to make complex multiple incisions in the atrial wall, the incision is like a “maze”, so it is called “maze surgery”, although it can eliminate atrial fibrillation, but the surgery is complex and traumatic, and is now less commonly used. In recent years, foreign countries in heart valve disease, coronary heart disease surgery at the same time, the application of radiofrequency ablation instead of the traditional incision and suture, simplify the surgical operation, reduce the surgical complications, the application is becoming more and more widespread. However, because the mechanism of AF generation has not been clarified, the scope and path of ablation have not been standardized, the cases that remain AF after surgery or recur AF in a short period of time account for about 30%, and some of them even have more serious arrhythmias. Therefore, the application of this procedure in China is limited. During his training in the United States, Deputy Director of Cardiac Surgery, Mr. Bi Yanwen, together with the famous cardiac electrophysiology expert, Dr. Clyne, applied advanced catheter balloon electrode to accurately locate and measure the potential changes in the atria, and carried out the research on the mechanism of AF and surgical treatment of cardiac valvulopathy, which confirmed that nearly 75% of the abnormal atrial fibrillation of AF in patients with rheumatic valvular disease and AF originated from the opening of the pulmonary vein. On this basis, the traditional labyrinthine surgical pathway was further simplified and improved, with radiofrequency ablation focusing on complete isolation of the pulmonary vein openings. This not only increased the accuracy of the procedure, but also avoided the cardiac damage caused by blind ablation, and the success rate of the procedure was significantly improved. The radiofrequency ablation modified maze procedure has proven to be a safe and effective method for eliminating AF in patients with heart valve disease combined with AF. Emphasizing the treatment of AF and widely carrying out this procedure can significantly improve the quality of life of patients with heart valve disease and coronary heart disease after surgery, reduce the burden of patients and society in many aspects of the treatment of atrial fibrillation, and have important social and economic significance.