ST-segment elevation myocardial infarction (STEMI) is an acute manifestation of coronary heart disease, remaining a frequent cause of death. A better understanding of risk factors and pathogenic mechanisms underlying STEMI may help improve the prognosis and life quality of these patients. Melatonin is the chief indoleamine produced by the pineal gland, and a well-known antioxidant and free radical scavenger. Basic studies have showed that melatonin is associated with myocardial infarction and heart failure. However, no study has evaluated whether melatonin is associated with adverse clinical outcomes in STEMI patients.

Inclusion Criteria:

a diagnosis of STEMI and needed PCI

Exclusion Criteria:

patients with cancer patients who used melatonin

PLA general hospital (PLAGH) is a large national tertiary-care center in the Beijing, China. The investigators enrolled all patients consecutively hospitalized in PLAGH, with a diagnosis of STEMI and needed PCI.