A Study Evaluating the Efficacy and Safety of Abciximab, an Anti-platelet Therapy, in Patients Undergoing High-risk Coronary Angioplasty

Inclusion Criteria: * Patients referred for elective or urgent coronary balloon angioplasty or atherectomy with an FDA-approved device in one of the following settings: unstable angina or non-Q wave myocardial infarction, acute Q-wave myocardial infarction, or high-risk clinical/morphological characteristics Exclusion Criteria: * Patients with a history of hemorrhagic diathesis - Having had major surgery or clinically significant gastrointestinal or genitourinary bleeding within 6 weeks of study enrollment * Having had a stroke within 2 years prior to enrollment or any stroke with significant residual neurological deficit * Having occlusion of the left main coronary artery greater than 50% or a history of vasculitis * Treated with oral anticoagulants within 7 days (unless prothrombin time is =\< 1.2 times control) or intravenous dextran (before or planned for during the treatment angioplasty)