Atrial fibrillation, also known as AFib, is a common arrhythmia that causes the regular and orderly electrical activity of the atria to be lost and replaced by rapid and disordered fibrillation waves. It is a severe disruption of the atrial electrical activity, which can lead to irregular ventricular rates, impaired cardiac function, and the formation of atrial mural thrombi in patients. The severity of symptoms in patients with atrial fibrillation is affected by the speed of the ventricular rate. When the ventricular rate is not fast, patients may be asymptomatic. When the ventricular rate increases, patients may experience palpitations, shortness of breath, a fluttering or irregular heartbeat, restlessness, fatigue, etc. On auscultation, an irregular heart rate can be heard, with unequal intensity and rhythm of heart sounds. In addition, there may be a pulse deficit and polyuria. An excessively fast heart rate can cause low blood pressure and even syncope. Patients may also experience angina, congestive heart failure, and concurrent systemic circulation embolism. The treatment of atrial fibrillation should first actively identify the primary disease and precipitating factors and take corresponding measures. Anticoagulation therapy is required, usually with oral warfarin. Methods to convert atrial fibrillation to sinus rhythm include pharmacological conversion, electrical conversion, and catheter ablation. These are the characteristics of atrial fibrillation.