This is a prospective, randomized study with blinded outcome assessment, comparing routine manual thrombus aspiration with no aspiration in patients with acute ST-segment elevation myocardial infarction (STEMI) underwent percutaneous coronary intervention (PCI).

This is a prospective, randomized study with blinded outcome assessment, comparing routine manual thrombus aspiration with no aspiration in patients with acute ST-segment elevation myocardial infarction (STEMI) underwent percutaneous coronary intervention (PCI). Patients who are diagnosed as STEMI and referred for PCI will be enrolled. They will be randomized 1:1 to either manual thrombus aspiration with PCI group or PCI alone group.The primary outcome is the composite of cardiovascular death, recurrent myocardial infarction (MI), cardiogenic shock, stroke, new or worsening NYHA class IV heart failure during 1 year follow-up. The secondary efficacy outcome are stent thrombosis, target vessel revascularization, left ventricular function and quality of life during 1 year follow-up.

Inclusion Criteria:

• Age between 18-80;
• Diagnosed as STEMI for presenting symptoms or definite ECG and myocardial markers changes;
• Patients presenting with definite ECG changes indicating STEMI: ST elevation of 0.1 mV in 2 contiguous limb leads or ≥0.2 mV in 2 contiguous precordial leads;
• Referred for PCI for presenting symptoms, and the coronary angiogram (CAG) shows that the initial TIMI thrombus grade ≥2;
• Informed consent.

Exclusion Criteria:

• Previous history of myocardiopathy, valvular heart disease or severe heart failure;
• Severe hepatic or renal dysfunction;
• Life expectancy less than 1 year;
• Prior PCI or CABG;
• Contraindications of using anticoagulation or antiplatelet drugs.