A Randomized, Single-blind, Controlled Clinical Study of Cardiomyopeptidin on Improving Ischemia-reperfusion Injury in Patients With Acute ST-segment Elevation Myocardial Infarction After Primary PCI

Inclusion Criteria: * STEMI patients: typical chest pain lasting 30 min within the previous 12 h, a clear ST-segment elevation of N0.1 mV in ≥2 contiguous electrocardiographic leads, and elevated blood levels of troponin T * patients were scheduled to undergo diagnostic cardiac angiography or percutaneous coronary interventions Exclusion Criteria: * had once treated by ivabradine * history of myocardial infarction * mechanical complications * Unable to perform myocardial MRI * liver and kidney failure * malignant tumor * unconscious * Patients with other significant abnormal signs, laboratory tests and clinical disease are unsuitable for participation in the study accessed by clinicians.