Ticagrelor Single Antiplatelet Therapy in Patients With High Risk of Bleeding After DCB for Coronary Small Vessel Disease

Inclusion Criteria: 1. CHD patients aged 18-80 with clear indications for PCI, regardless of gender; 2. Received DCB treatment with only one small coronary artery (diameter 2.0-2.75mm); 3. High risk of bleeding (ARC high risk criteria for bleeding): Meets at least one main criterion (use of anticoagulants, liver dysfunction, tumors, history of gastrointestinal bleeding, history of peptic ulcers, creatinine clearance rate\<30mL/min, hemoglobin\<11g/L, platelet count\<100 × 109/L) or 2 sub criteria (age ≥ 75 years old, creatinine clearance rate\<60mL/min, history of stroke/TIA, hemoglobin 11-12.9g/L for males or 11-11.9g/L for females); 4. Willing to participate in trials and complete follow-up; 5. Signed an informed consent form approved by the Ethics Committee; Exclusion Criteria: 1. Simultaneously or plan to perform other coronary PCI procedures in batches, including stent implantation, DCB treatment for non-small vessel lesions, and DCB treatment for in stent restenosis lesions. 2. High ischemic risk: a. ACS within 1 year; b. Perform stent implantation or CABG surgery within 1 year; c. Double or multi vessel lesions rearched incomplete revascularization; d. In addition to the target lesions for DCB intervention, there are other stenosis ≥ 90%, regardless of whether PCI is planned or not; 3. Anticoagulant drugs are required for atrial fibrillation/deep vein thrombosis (including pulmonary embolism)/mechanical valve implantation; 4. Cardiomyopathy (HCM/DCM/RCM); 5. Severe ventricular arrhythmias requires radiofrequency ablation or ICD implantation; 6. Chronic obstructive pulmonary disease (bronchial asthma, chronic bronchitis, emphysema, pulmonary heart disease); 7. Serious infectious diseases, including active hepatitis B, hepatitis C or AIDS patients; 8. Blood system diseases with coagulation disorders such as thrombocytopenia, leukemia, and hemophilia; 9. Thrombotic diseases such as antiphospholipid antibody syndrome; 10. Cognitive impairment; 11. Not willing to participate in experiments or cooperate with follow-up;