The objective of this study is a comparative evaluation of BuMA Supreme™ stent and of Xience V/Prime stent in terms of the extent of neointima formation at 1 or 2 months after implanting in relatively high bleeding risk patients with coronary artery disease using OCT.

This is a prospective, multicenter, randomized, non-inferiority study, which will enroll a total of 80 subjects from approximately 8 centers. All subjects will be firstly randomly assigned to 1st month OCT (40 pts) or 2nd month OCT group(40 pts). Then both two groups will be randomly assigned to undergoing implantation of BuMA Supreme™ stent (20 pts) or Xience V/Prime stent (20 pts). If non-inferiority was met, superiority test will be planned.

All of the patients be followed up to 2 years. The follow-up visits will be conducted at 1 or 2 months (including QCA/OCT investigation), 3 months, 6 months, 1 and 2 years post percutaneous coronary intervention(PCI),in order to observe the Primary Endpoint and Secondary Endpoints.

Inclusion Criteria:

1. 18 to 85 years.

2. Evidence of myocardial ischemia without raised troponin (e.g. stable or unstable angina, silent ischemia demonstrated by positive territorial functional study).

3. Any one or more situation listed below can be considered the patient at high bleeding risk by the doctor:

   • Adjunctive oral anticoagulation treatment planned to continue after PCI；

   • Baseline Hb ≥11 g/dl (or anemia requiring TF during the prior 4 weeks)；

   • Any prior intra-cerebral bleed at any time；

   • Any stroke during the past year；

   • Hospital admission for bleeding during the prior 12 months；

   • Non-skin cancer diagnosed or treated ≤ 3 years；

   • Planned daily NSAID (other than aspirin) or steroids for ≥ 30 days after PCI；

   • Planned major surgery (within 1 year)；

   • Renal failure (calculated creatinine clearance ≥ 40 ml/min)；

   • Thrombocytopenia (≥ 100,000/mm3)；

   • Severe chronic liver disease (variceal hemorrhage, ascites, hepatic encephalopathy or jaundice)；

   • Expected non-compliance to prolonged DAPT for other medical (nonfinancial)reasons ；

     • NSAID, Non-steroidal anti-inflammatory drug; TF, blood transfusion.

4. The patient has a planned intervention of up to two de novo lesions, in different epicardial vessels.

5. Lesion(s) must have a visually estimated diameter stenosis of ≥70% and <100%.

6. Reference Vessel Diameter (RVD) must be between 2.5- 4.0mm, and the vessel length must be no more than 40 mm.

7. Written informed consent.

8. The patient and the patient's physician agree to the follow-up visits including angiographic follow-up and OCT controls at 1 or 2 month.

Exclusion Criteria:

1. Evidence of ongoing acute myocardial infarction in ECG prior to procedure.
2. Left ventricular ejection fraction (LVEF) <30%.
3. The patient is a recipient of a heart transplant.
4. Known hypersensitivity or contraindication to aspirin, both heparin and bivalirudin, antiplatelet medication specified for use in the study (clopidogrel and ticlopidine), sirolimus or stainless steel, cobalt metal or sensitivity to contrast media, which cannot be adequately pre-medicated.
5. Other medical illness (e.g. skin cancer diagnosed or treated > 3 years, neurological deficiency) or known history of substance abuse (alcohol etc.) as per physician judgment that may cause non-compliance with the protocol or confound the data interpretation or is associated with a limited life expectancy.
6. Pregnant or breastfeeding woman or woman in fertile period not taking adequate contraceptives
7. Chronic total occlusion(TIMI 0), left main lesion, intervention-required three-vessel lesions, branch vessel diameter ≥ 2.5mm and bypass lesion
8. Patients expected not to comply with 1 month DAPT；
9. Compliance with long-term single anti-platelet therapy unlikely；
10. Active bleeding at the time of inclusion；
11. Patients requiring a planned staged PCI procedure more than one week after theindex procedure；
12. Procedure planned to require non-study stents, or stand alone POBA or stand-alone atherectomy；
13. Reference vessel diameter <2.25 - >4.0mm, vessel length >40mm；
14. Cardiogenic shock；
15. Participation in another clinical trial (12 months after index procedure).
16. Those who is not suitable to attend this trial after the evaluation by the doctor.

OCT exclusion criteria

• Severe tortuous, calcified or angulated coronary anatomy of the study vessel that in the opinion of the investigator would result in suboptimal imaging or excessive risk of complication from placement of an OCT catheter
• Total occlusion or thrombolysis in myocardial infarction(TIMI) flow 0, prior to wire crossing.