A Multi-center Study of Apixaban(APPROACH)

• age between 18 to 85 years;
• understand the purpose of the trial, sign the informed consent form voluntarily
• successful surgery (no pericardial effusion, pericardial tamponade, or device displacement during operation; no pericardial effusion before discharge), meet COST standard during operation.
• In accordance with the indications for left atrial appendage occlusion: CHA2DS2-VAS2 score≥2 points and/or HAS-BLED score≥3 points
• unable or unwilling to take oral anticoagulants
• life expectancy≥1 year

Exclusion Criteria:

• History of previous cardiac surgery (valve disease, cardiomyopathy, severe coronary occlusion);
• Inability to tolerate trans-esophageal echocardiography;
• Preoperative trans-esophageal echocardiography suggests thrombus in left atrial appendage/left atrial;
• Patients with severe renal insufficiency (creatinine clearance rate\<15ml/min);
• Patients with liver disease accompanied by abnormal blood coagulation and clinically related bleeding risks;
• Clinically significant active bleeding;
• The baseline platelet count is severely reduced: PLT≤50*10\^9/L;
• Severe cardiac insufficiency (preoperative transthoracic echocardiography indicated LVEF \<35%; uncontrolled heart failure (NYHA IV))
• Allergy or contraindication to anticoagulant drugs such as aspirin, clopidogrel, apixaban, etc .;
• Serious heart valve disease or other structural abnormalities need do elective surgical treatment; or severe coronary heart disease require limited-term intervention;
• Less than 45kg or more than 100kg.
• Take strong CYP3A4 and P-gp inhibitors (including pyrrole antifungal drugs, HIV protease inhibitors, etc.) for systemic treatment;
• Patients with other diseases besides atrial fibrillation (such as after mechanical valve replacement, spontaneous or recurrent venous thromboembolism, etc.) need anticoagulation treatment;
• Unsuccessful surgery (serious pericardial tamponade, massive bleeding and other life-threatening complications occur within 3 days after left atrial appendage closure);
• Pregnancy or lactation;
• Participating in other uncompleted clinical trials;
• Investigator considers inappropriate subjects.