Effectiveness of Clopidogrel Resinate in PCI(PRIDE)

Inclusion Criteria: * The patient must be at least 18 years of age. * Patients with symptomatic coronary artery disease with objective evidence of ischemia (e.g. symptoms of angina pectoris, positive stress test results, or dynamic ECG changes). * Patients are referred for PCI, or thought to be at high likelihood for requiring stent placement with or without conventional balloon angioplasty * The patient or guardian agrees to the study protocol and the schedule of clinical and angiographic follow-up, and provides informed, written consent, as approved by the appropriate Institutional Review Board/Ethical Committee of the respective clinical site. Exclusion Criteria: * The patient has a known hypersensitivity or contraindication to any of the following medications: * Heparin * Aspirin * Both Clopidogrel and Ticlopidine * Stainless steel and/or * Contrast media (patients with documented sensitivity to contrast which can be effectively pre-medicated with steroids and diphenylhydramine \[e.g. rash\] may be enrolled. Patients with true anaphylaxis to prior contrast media, however, should not be enrolled). * Coronary anatomy not amenable to stent placement * Female of childbearing potential, unless a recent pregnancy test is negative, who possibly plan to become pregnant any time after enrollment into this study. * History of bleeding diathesis or known coagulopathy (including heparin-induced thrombocytopenia), or will refuse blood transfusions. * Gastrointestinal or genitourinary bleeding within the prior 3 months, or major surgery within 2 months. * Current known current platelet count \<100,000 cells/mm3 or Hgb \<10 g/dL. * An elective major surgical procedure is planned that would necessitate interruption of thienopyridines during the first 1 year post enrollment. * Non-cardiac co-morbid conditions are present with life expectancy \<1 year or that may result in protocol non-compliance (per site investigator's medical judgment). * Patients who are actively participating in another drug or device investigational study, which have not completed the primary endpoint follow-up period. * Administration of the following medications prior to randomization: GpIIb-IIIa inhibitor and clopidogrel within 7 days (already received pretreatment), or thrombolytics within 24 hours. * Long-term (at least \> 3 months) use or requirement of NSAID or anticoagulation * Patients with cardiogenic shock * Acute MI patients within symptom onset \< 12 hours needing primary angioplasty * Patients with left main stem stenosis (\>50% by visual estimate)