Atrial fibrillation is a type of tachyarrhythmia in which the atria are paced instead of the normal pacing point, and the atrial excitation rate can be 350-600 beats per minute. Atrial fibrillation is one of the most common types of tachyarrhythmias in clinical practice. It occurs in patients with structural changes in the atria due to organic heart disease, and thyroid abnormalities and alcohol-related myocardial damage are also risk factors for the development of AF. Atrial fibrillation that occurs in healthy people with no obvious cause is called idiopathic atrial fibrillation and is also more common in clinical practice. Atrial fibrillation can be divided into primary atrial fibrillation, which occurs for the first time, paroxysmal atrial fibrillation, which can be terminated by repeated episodes, persistent atrial fibrillation, which can be converted to sinus rhythm with treatment, and permanent atrial fibrillation, which is difficult to convert and maintain sinus rhythm. The symptoms of atrial fibrillation are related to the type of atrial fibrillation, the fast or slow ventricular rate, and the underlying cardiac structure. Acute paroxysmal atrial fibrillation may have severe palpitations, chest tightness, shortness of breath, and in severe cases, blackness or even syncope, while a small percentage of patients have no symptoms. Patients with chronic persistent atrial fibrillation may not have any cardiac symptoms and may only show a progressive decrease in activity tolerance. Patients with underlying heart disease may have worsening cardiac function due to atrial fibrillation. Atrial fibrillation can be characterized by heart auscultation and pulse during the attack, which is characterized by varying heart rate, varying intensity of heart sounds, absolutely irregular rhythm, and a pulse rate less than the heart rate. The diagnosis of atrial fibrillation is mainly based on a clear ECG at the time of the attack. Because atrial fibrillation may cause intense discomfort, long-term atrial fibrillation may change the structure and function of the patient’s heart, and thrombotic complications of atrial fibrillation may even be life-threatening. It is important to seek prompt medical attention when atrial fibrillation is detected or suspected, regardless of the presence or absence of symptoms. Atrial fibrillation is one of the common arrhythmias. Acute atrial fibrillation may cause discomfort, while long-term atrial fibrillation may affect the structure and function of the heart and may cause life-threatening complications such as acute thromboembolism.