The heart has a small tissue called the sinus node, which is the commander that controls the entire heartbeat, and it regularly and regularly distributes bioelectricity, which reaches the entire heart through the conduction tissue, causing the heart to produce synchronized and coordinated contractions. When atrial fibrillation occurs, the control function of the sinus node is lost, and another kind of bioelectricity is distributed by one part of the atria, which is fast and irregular, causing the contraction of the atria to stop and causing the ventricles to have fast irregular beats, up to 100-150, and in some cases up to 200, and the heart rate is not consistent with the pulse rate at this time. Atrial fibrillation is not an independent disease, it can be complicated by many other heart diseases, such as rheumatic heart valve disease, coronary heart disease, hypertension, cardiomyopathy, etc. It can be said that all heart diseases can occur atrial fibrillation, in addition to hyperthyroidism can also occur atrial fibrillation. Recently, atrial fibrillation is classified into paroxysmal atrial fibrillation, persistent atrial fibrillation and permanent atrial fibrillation. Atrial fibrillation that can be terminated by itself is paroxysmal atrial fibrillation, atrial fibrillation that can be terminated by treatment is persistent atrial fibrillation, and atrial fibrillation that cannot be terminated by treatment is permanent atrial fibrillation. Treatment of atrial fibrillation: There are centralized methods to revert and maintain sinus rhythm or prevent recurrence of atrial fibrillation, such as drugs, direct current shock, pacing, and radiofrequency ablation. The goal of atrial fibrillation treatment: in addition to the prevention of thromboembolic complications, remains the satisfactory control of the ventricular rate, the restoration of sinus rhythm and the prevention of its recurrence. There are two classes of antiarrhythmic drugs used for atrial fibrillation: 1. Drugs to revert atrial fibrillation, restore sinus rhythm and prevent recurrence, including class IA, IC and III antiarrhythmic drugs. They mainly act on the atria to prolong the atrial induction period or slow down the intra-atrial conduction. 2. Drugs that slow down the ventricular rate, including β-blockers, non-dihydropyridoxine calcium antagonists and digitalis drugs. They act on the atrioventricular node to prolong the atrioventricular nodal induction period and increase cryptic conduction, thereby slowing the ventricular rate.