Tailored Anti-platelet Therapy After DES Implantation in High-risk Patients

Inclusion Criteria: 1. Patients \> 18 years old 2. Patients who previously underwent percutaneous coronary intervention with drug-eluting stent implantation 12 months (± 3 months) ago. 3. At least one high risk characteristics of ischemic events High risk patients 1. Acute coronary syndrome 2. Previous history of cerebrovascular accidents 3. Previous history of peripheral artery intervention 4. Heart failure 5. Diabetes mellitus requiring medication 6. Chronic kidney disease (regardless of requirement of renal replacement therapy) High risk lesions 1. Left main disease 2. Multivessel disease, 2- or 3- vessels 3. Bifurcation lesions requiring 2 or more stents 4. Chronic total occlusion 5. In-stent restenosis 6. Graft lesions 7. Diffuse long lesion requiring stent(s) with total stent length ≥28 mm 8. Lesion at small sized vessel requiring stent(s) with stent diameter ≤2.5 mm 9. Calcified lesions requiring atherectomy Exclusion Criteria: 1. Patients \> 80 years old 2. Pregnant women or women with potential childbearing 3. Life expectancy \< 1 year 4. Refusal or inability to understand of informed consent 5. Patients eligible to long-term anticoagulation therapy 6. Patients with major bleeding events in previous 3 months before randomization