Chen Gang, Department of Cardiovascular Medicine, Fu Wai Hospital, Beijing, China, replied: Three years ago, the patient visited the hospital for atrial flutter due to precordial disease, post-operative atrial defect and valve closure insufficiency, and was hospitalized for radiofrequency ablation treatment. Recently, the patient had a heart attack and was diagnosed as “atrial fibrillation” in the external electronic medical record. The diagnosis could not be confirmed because there was no electrocardiogram. Atrial fibrillation is a major cause of atrial fibrillation, which can be caused by a heavy load on the atria due to incomplete valve closure or stenosis. It is recommended that patients with similar conditions should pay attention to rest, avoid straining and drinking alcohol, review an echocardiogram every year, and adjust treatment under the guidance of a doctor to reduce the burden on the heart and prevent the occurrence of atrial fibrillation. Chen Gang, Department of Cardiovascular Medicine, Fu Wai Hospital, Beijing, China