Efficacy of Early Rhythm Control Therapy in Patients With Subclinical Atrial Fibrillation

The goal of this study to find out the efficacy of early rhythm therapy in patients with subclinical atrial fibrillation detected by Cardiac Electronic Implantable Devices. Early rhythm therapy includes antiarrhythmic drug, cardioversion, and catheter ablation. The general control group receives general management without the above atrial fibrillation rhythm control treatment. Researchers will compare early rhythm control groups to general control groups to see if early rhythm therapy works to reduce the atrial fibrillation burden by 50% or more, or decrease the incidence of clinical AF documentation. Participants will: * Randomly allocated to two groups at a 1:1 ratio. * Receive the treatment according to their assigned group. * Visit the clinic once every three months for checkups and tests.