Efficacy and Safety in Patients With Acute Coronary Syndrome Without ST-Segment Elevation

Inclusion Criteria: Patients aged above 20, admitted to hospitals with symptoms suspected to represent an acute coronary syndrome defined as unstable angina or acute MI without ST segment elevation greater than 1 mm are eligible for the study if they meet the following criteria: (1)Clinical history consistent with new onset or worsening pattern of characteristic ischemic chest pain occurring at rest or with minimal exercise (lasting longer than 5 minutes or requiring sublingual nitroglycerin for the relief of pain within 24 hours before registration). (2)Patients who meet either of following criteria ECG changes compatible with new ischemia [e.g. ST depression (at least 1 mm), T wave inversion (at least 2 mm), or hyperacute peaked T waves in 2 contiguous leads]. already elevated CK at least twice the upper limit of normal or CK-MB or Troponin I or T above the upper limit of normal or positive qualitative test for Troponin T. (3)A percutaneous coronary intervention is planned within 96 hours after the first study drug administration Exclusion Criteria: A)Factors that affect participation in study: (1)Previous disabling stroke (2)Previous intracranial hemorrhage or hemorrhagic stroke (3)Severe co-morbid condition such that the patient is not expected to survive 1 month (4)NYHA Class IV heart failure (5)Uncontrolled hypertension (6)Requirement for use of oral anticoagulants, non study antiplatelet agents (including ticlopidine) or NSAIDs (excluding unum sumatur), during study period, B)Factors related to ASA and/or ticlopidine treatment: (1)Use of ticlopidine within 1 week prior to randomization (2)History of ASA or ticlopidine intolerance or allergy (3)Contraindications to ASA or ticlopidine