Inclusion Criteria:  diabetic patients with ST- elevation myocardial infarction (STEMI ) treated with primary Percutaneous Coronary Intervention ( PCI ) .  Exclusion Criteria:  diabetic patients with ST- elevation myocardial infarction (STEMI ) treated with primary Percutaneous Coronary Intervention ( PCI ) : but have  (1) a history of an unprotected left main artery with severe liver and kidney diseases or coronary artery bypass grafting .  (2) patients who had valvular disease or cardiomyopathy . (3) severe dissection, thromboembolism in other parts, or vasospasm; and known malignancy .  (4) patients with contraindications for anticoagulant therapy, such as active visceral hemorrhage, hemorrhagic stroke, or ischemic stroke within half a year (including transient ischemic attack), or aortic dissection, or patients with hematological diseases complicated with coagulation disorders .