Atrial fibrillation (AF for short) is very common and its prevalence increases with age. There is 1 in 25 people aged ≥60 years and 1 in 10 people aged ≥80 years with atrial fibrillation. There are currently about 8 million patients with AF in China, and AF has become an “epidemic” in the 21st century. Stroke is one of the major complications of atrial fibrillation, and about 90% of atrial fibrillation embolism complications are cerebral embolism, and 20% of ischemic strokes are caused by atrial fibrillation. Stroke due to atrial fibrillation is characterized by high incidence, high disability and high mortality. Paroxysmal atrial fibrillation is also associated with a high risk of stroke It was previously thought that although paroxysmal atrial fibrillation had a high risk of cerebral embolism during the acute phase of the attack, it did not have a high risk of stroke during the remission phase. Recently, a growing number of studies have suggested that the risk of stroke in paroxysmal AF is as high as that in persistent and permanent AF. A study of 3890 patients with various types of atrial fibrillation showed that the incidence of ischemic stroke at 1-year follow-up was similar, with 1.3% for first diagnosis of atrial fibrillation, 1.9% for paroxysmal atrial fibrillation, 1.2% for persistent atrial fibrillation, and 1.6% for permanent atrial fibrillation, and the risk of stroke from paroxysmal atrial fibrillation was similar to that of persistent and permanent atrial fibrillation. 2. Cryptogenic stroke may be caused mainly by paroxysmal atrial fibrillation The cause of approximately 20% to 40% of ischemic strokes cannot be determined. In such cryptogenic strokes, it is speculated that most may be due to cardiogenic cerebral embolism, despite normal cardiac examination. A study in the American Journal of Neurology showed that cryptogenic stroke may be caused primarily by paroxysmal atrial fibrillation. In this study, patients with cryptogenic stroke or cryptogenic transient ischemic attack (TIA) within 3 months of onset were monitored for atrial fibrillation using a portable remote ECG recorder. A total of 23% of patients were found to have atrial fibrillation during 21 days of monitoring, 85% of whom had atrial fibrillation of less than 30 seconds duration and 15% had atrial fibrillation of 4 to 24 hours duration. 3. Patients with asymptomatic cerebral infarction have a 2-fold increased risk of developing atrial fibrillation It is well established that patients with asymptomatic cerebral infarction are at least 5 times more likely than patients with symptomatic cerebral infarction, and patients with asymptomatic cerebral infarction have an approximately 3-fold increased risk of symptomatic cerebral infarction and an approximately 2.3-fold increased risk of vascular dementia than subjects with normal brain magnetic resonance imaging (MRI) examinations. The study reported that in a “healthy” population with an average age of 62 years (53% female), 10.7% of subjects who underwent brain MRI had asymptomatic cerebral infarction, of which a single cerebral infarct lesion accounted for 84%, and patients with asymptomatic cerebral infarction had a 2-fold increased risk of developing atrial fibrillation compared to subjects with normal brain MRI. 4. Anticoagulation is most effective in preventing stroke in patients with atrial fibrillation Unless the patient has a contraindication, all patients with atrial fibrillation should receive antithrombotic therapy. Warfarin anticoagulation therapy (INR 2.0-3.0) or aspirin (81-325 mg/d) is the preferred choice. In primary prevention of stroke in AF, warfarin anticoagulation reduced the relative risk of stroke by 62% compared with placebo and prevented 1 serious vascular event for every 37 cases treated for 1 year, whereas aspirin reduced the relative risk of stroke by only 22% compared with placebo and required 67 cases treated for 1 year to prevent 1 serious vascular event. Warfarin was more effective than aspirin in reducing the risk of stroke (risk ratio 0.36; 95% confidence interval 0.26-0.51). In secondary prevention of stroke in patients with atrial fibrillation, warfarin anticoagulation reduced the relative risk of stroke by 67% compared with placebo and prevented 1 serious vascular event for every 13 cases treated for 1 year, whereas aspirin reduced the relative risk of stroke by only 21% compared with placebo and required 40 cases treated for 1 year to prevent 1 serious vascular event. 5. Surgical ultra-minimally invasive surgery can completely prevent stroke Surgical ultra-minimally invasive surgery can cure various types of atrial fibrillation with high cure rate, and at the same time, the left heart ear, which is the origin of stroke, is removed during surgery, which eliminates the occurrence of various left heart ear thrombosis, cerebral embolism and stroke. It is the most effective treatment method at present.