Clinically, stroke is one of the greatest dangers of atrial fibrillation. Atrial fibrillation occurs when the ordered electrical activity of the atria is lost and the effective contractile function of the atria is lost. At this point, the blood flow in the atria is vortexed, and when atrial fibrillation persists for more than 48 hours, a thrombus may be created in the atria. When the resulting thrombus is dislodged, it will flow with the arterial blood flow and stop wherever it stops, which may cause blockage of the corresponding part of the blood vessel, such as cerebral embolism, lower limb artery embolism, mesenteric artery embolism, etc. Among these embolic events, the most common is cerebral embolism, or stroke, which is often referred to as “stroke”. Stroke is one of the greatest hazards of atrial fibrillation. The incidence of stroke in patients with non-valvular atrial fibrillation is 5.6 times higher than normal, and the incidence of stroke in valvular atrial fibrillation is 17.6 times higher than normal; and the consequences of stroke caused by atrial fibrillation are more serious, with a disability rate of about 25% and a mortality rate of 25%.