1.Incipient atrial fibrillation: atrial fibrillation that is first detected, including paroxysmal and persistent. 2, Paroxysmal atrial fibrillation: atrial fibrillation that lasts ≤7 days and can be terminated by itself. 3.Persistent atrial fibrillation: atrial fibrillation that lasts >7 days or can be terminated only after interventions such as electrical/pharmacological cardioversion. 4.Long-term persistent atrial fibrillation: atrial fibrillation that lasts >1 year. 5, permanent atrial fibrillation: atrial fibrillation that cannot be terminated or relapses after termination and is no longer considered to be reversible. 6.Non-valvular atrial fibrillation: Atrial fibrillation that is not combined with rheumatic mitral stenosis, after mechanical or biological valve replacement and after mitral valve repair.