Major exclusion criteria are: Complete left bundle branch block, Previous myocardial infarction at the same site, Post-anoxic coma, Known thrombocytopenia or leucopenia, Previous episodes of hemorrhagic diathesis or allergy to ASA or thienopyridine; Anticoagulant therapy with dicumarol with INR > 2; Previous treatment with thrombolytics (within the previous 48 hours).