 This study is a randomized clinical trial RCT evaluating the effect of omega 3 supplement with 400mg Eicosapentaenoic acid EPA and 200mg docosahexanoic acid DHA on short-term within 30 days and long-term after one year major adverse cardiac events MACE in patients undergoing elective PCI. Eighty patients planed to do elective PCI will be categorized into two groups. The first group will be received standard regimen for PCI aspirin, clopidogrel, and heparin and the second group will be treated with standard regimen in addition to 3 gram omega 3 12 hours before PCI. The main end point of the trial was short-term within 30-days and long-term after one year incidence of MACE death, myocardial infarction, or unplanned revascularization. 