This study is a meta-analysis of previously published studies. Therefore, the eligibility criteria may be diverse according to the individual studies.  --------------------------  Inclusion Criteria:  Subject must have clinical diagnosis of acute coronary syndrome  Exclusion Criteria:  The patient has a known hypersensitivity or contraindication to any of the following medications: Heparin, Aspirin, Clopidogrel, Prasugrel, Ticagrelor