This study is aiming to test the hypothesis that efficacy of rhTNK-tPA was not inferior to rt-PA with respect to the 30-day MACCE rates after fibrinolytic therapy for STEMI patients. It is a multicenter, randomized, open, parallel, active-controlled, non-inferiority trial.

The study includes screening and baseline, randomization & intervention, in-hospital visit, at 30±3 days visit after fibrinolytic therapy.

Following an initial eligibility screening assessment, all eligible patients who have signed the informed consent will be randomly assigned by an interactive Web-based central system for fibrinolytic therapy with either rhTNK-tPA or rt-PA. The standard care should be given to all patients except for the study interventions.

Prior to fibrinolytic administration, enoxaparin (30-mg intravenous) or Un- Fractionated Heparin (maximum 4000U, intravenous) should be administered, combined with antiplatelet therapy consisted of both clopidogrel and aspirin in a 300-mg loading dose followed by routine dosage.

Successful reperfusion according to the clinical evidence (EKG) should be assessed after fibrinolytic therapy.TIMI flow should be assessed for those patients with 24 hours coronary angiography.

MACCE and bleeding events should be followed up and documented during the study until 30 days after fibrinolytic therap. An independent adjudication committee will judge the major endpoint events.

Inclusion Criteria:

1. Diagnosis of acute STEMI（meet with both conditions）:

   • Ischemic chest pain ≥30mins in duration
   • ST elevation ≥0.1 mV in two or more limb ECG leads or ≥0.2 mV in two or more contiguous precordial leads

2. Onset of continuous ischemic symptoms of STEMI ≤6 hours prior to randomisation

3. Anticipated Delay to Performing Primary PCI >60mins，or time from hospital arrival to to balloon inflation >90mins

4. Signed Informed consent received prior to participation the study

Exclusion Criteria:

1. Non-ST-segment-elevation myocardial infarction or unstable angina

2. Reinfacrtion

3. Cardiacgenic shock

4. Suspected aortic dissection

5. New left bundle branch block in ECG

6. Absolute and relative contraindications for Fibrinolytic Therapy in STEMI(referred from 2015 China STEMI Management Guideline）：

   • Severe uncontrolled hypertension (unresponsive to emergency Therapy,BPs > 180 mmHg and/or BPd > 110 mmHg)
   • Any prior ICH,stroke with unknown cause, Ischemic stroke within 3 months
   • Known structural cerebral vascular lesion, malignant intracranial neoplasm
   • Active bleeding, or bleeding diathesis, active peptic ulcer
   • Significant closed-head or facial trauma within 3 months
   • Intracranial or intraspinal surgery within 2 months
   • Recent internal bleeding within 4 weeks
   • Major surgery within 3 weeks, or Traumatic
   • Prolonged cardiopulmonary resuscitation (>10 minutes)
   • Noncompressible vascular punctures within 2 weeks
   • Current use of anticoagulant therapy

7. Current or with a history of significant diseases：

   • Damage to the central nervous system
   • Severe renal or hepatic dysfunction, blood system diseases,
   • Present with cardiac rupture evidence
   • Acute pericarditis,Subacute bacterial endocarditis, Septic thrombophlebitis or occluded AV cannula at seriously infected site
   • Malignancy
   • High likelihood of left heart thrombus, e.g., mitral stenosis with atrial fibrillation
   • Diabetic hemorrhagic retinopathy or other hemorrhagic ophthalmic conditions
   • History of PCI or coronary artery bypass graft（CABG）within 1 month

8. Administration of fibrinlytic therapy prior to participation

9. Weight below 50 kg

10. Known current histroy of fall-down accident

11. Any other unfavourable conditions for participation：

    • Known participation in other clinical trials
    • Known to allergic to rhTNK-tPA or tPA or relevant vehicle
    • Pregnancy or lactation
    • Mental disorder
    • Present with any unsuitable conditions for participation or completion of the study at the discretion of their treating physician