Effect of Indobufen and Aspirin on Platelet Aggregation and Long Term Prognosis in Patients With Coronary Heart Disease

Inclusion Criteria: 1. 18 years \< age ≤ 85 years; 2. Patients with confirmed stable coronary heart disease (must meet at least one of the following conditions); 2.1 a stenosis confirmed by Coronary angiography or dual-source CT, but the stenosis of the Left Main Artery (LMA) diameter is less than 50%, the stenosis of the left anterior descending branch（LAD）is less than 70%, and the stenosis of the two or three coronary arteries diameter is less than 70%, patient has no corresponding evidence of ischemia; 2.2 Patients after percutaneous coronary intervention (PCI): Dual antiplatelet therapy (DAPT) time is greater than 9 months, without cardiovascular events and ischemic symptoms; and currently receiving aspirin 100 mg/d with clopidogrel 75 mg/d or ticagrelor 90mg (bid) dual antiplatelet therapy. 2.3 Patients after coronary artery bypass graft (CABG): Dual antiplatelet therapy (DAPT) time is greater than 9 months, without cardiovascular events and ischemic symptoms; and currently receiving aspirin 100 mg/d with clopidogrel 75 mg/d or ticagrelor 90mg (bid) dual antiplatelet therapy. 3. Willing to sign the informed consent. Exclusion Criteria: 1. Acute coronary syndrome (ACS) occurred within 3 months before screening; 2. Percutaneous coronary intervention or CABG surgery within 9 months before screening; 3. Any other conditions (such as atrial fibrillation, pulmonary embolism, lower extremity venous thrombosis, artificial heart valve, etc.) who need oral or intravenous anticoagulation treatment; 4. In the past 3 months, the Arachidonic acid-induced platelet aggregation rate≥ 50%; inhibition rate ≤ 20% in the aspirin combined with clopidogrel treated patients; 5. Congestive heart failure or left ventricular ejection fraction \<35%; 6. A positive history of Chronic Obstructive Pulmonary Disease (COPD); 7. bleeding tendency or severe lung disease; 8. Active pathological bleeding; 9. History of intracranial hemorrhage (less than 3 months); 10. Allergic to indobufen / aspirin (or any of its ingredients); 11. Severe liver injury (transaminases exceeding the upper limit of 2 times and above); 12. Pregnancy, lactation and those who have a birth plan; 13. Hematological diseases, platelet count \<100000 / mm3 or hemoglobin \<10g / dL; 14. Have a history of drug or alcohol abuse in the past 2 years; 15. Use of non-steroidal anti-inflammatory drugs (within 3 months); 16. Creatinine clearance \<30ml/min;