The main hazards of atrial fibrillation are as follows (1) blood stasis in the atrium is easy to form thrombus, dislodgement leads to cerebral embolism limb paralysis, heart, intestines, kidneys, limbs and other parts of the embolism; (2) frequent episodes can lead to significant atrial enlargement, and the left atrial volume of some patients increases 2-3 times in 2-3 years; (3) atrial contraction incoherence, partial loss of cardiac function, generally estimated to be 15-20%, aggravate and deteriorate existing heart failure; (4) frequent episodes of panic, dizziness, blackness and even fainting.