The purpose of the study is to evaluate the efficacy and safety of bivalirudin in AMI patients with DES.

This is a prospective, randomized, single-blind, active drug controlled multicenter clinical research and the study would enrolled a total of 380 AMI patients undergoing percutaneous coronary intervention (PCI) to one of two antithrombotic regimens: bivalirudin alone, or unfractionated heparin alone. All enrolled patients would be followed-up to 30 days.

This is a prospective, randomized, single-blind, active drug controlled multicenter clinical research and the study would enrolled a total of 380 AMI patients undergoing percutaneous coronary intervention (PCI) to one of two antithrombotic regimens: bivalirudin alone, or unfractionated heparin alone. All enrolled patients would be followed-up to 30 days. The purpose of the study is to evaluate the efficacy and safety of bivalirudin in AMI patients with DES.

Inclusion Criteria:

1. Age 18 to 80 years old
2. Planned emergency PCI for acute myocardial infarction (STEMI) Symptom onset within 12h for STEMI (or within 12-24 hrs for patients have unrelieved chest pain, continuous ST elevation or new developed LBBB)
3. Provide written informed consent.

Exclusion Criteria:

1. Age <18 or >80 years.
2. Any anticoagulant drugs were regularly used within 3 months.
3. Any anticoagulant agents were used 48 h before randomization.
4. Active bleeding or bleeding constitution, bleeding tendency, including the recent retina or vitreous hemorrhage (1 months), GI or urinary tract hemorrhage (3 months), cerebral hemorrhage (6 months) or cerebral infarction history (3 months), etc.
5. Hemoglobin < 90 g/L or platelet count < 100 * 109 / L.
6. Untreated or uncontrolled hypertension > 180/110 mmHg.
7. Elevated ALT level higher than three times of the normal upper limit;severe renal insufficiency (eGFR < 30 mL/min / 1.73 m2).
8. Heparin induced thrombocytopenia.
9. Suspicious aortic dissection, pericarditis and subacute bacterial endocarditis.
10. Known allergy to the study drugs and instruments (UFH, bivalirudin, aspirin and clopidogrel, stainless steel, contrast agents, etc.), or those allergic constitution.
11. Pregnancy , lactation or plan to be pregnant.
12. Known serious progressive diseases such as malignant tumor or prognosis of the patients with severe failure;the survival time < 6 months.
13. Unsuitable for PCI.
14. Attended any clinical trial 1 month before randomised.