Eptifibatide and ST Segment Resolution Following Primary PCI

The aim of this study is to evaluate the effectiveness and safety of adjunctive eptifibatide during primary PCI in patients presenting to the catheterization laboratory within 12 hours of symptom onset. The primary objective of this randomized clinical trial is to examine the safety and effectiveness of the addition of eptifibatide therapy immediately prior to or at the time of PCI in patients presenting with a STEMI for primary PCI who have not received up-front glycoprotein IIb/IIIa inhibitor therapy. The secondary objective of this clinical trial is to assess effectiveness of adjunct eptifibatide therapy with respect to the following endpoints: * Complete ST resolution (defined above) at 90 and 180 minutes post primary PCI * TIMI flow at the end of the PCI (as reported by the investigator at the end of the procedure) * MACE evaluation at discharge and 30 days post PCI (MACE defined as: death, reinfarction, and need for urgent ischemia-driven target vessel revascularization) * Stent thrombosis at discharge and 30 days * Major Bleed (Major Bleed defined as: TIMI Major Bleeding) * Minor Bleed (Minor Bleed defined as: TIMI Minor Bleeding) * ST segment resolution at 60, 90 and 180 minutes based on the additional measure in the Schroder's Index: * Partial resolution defined as 30-70% ST-segment resolution, and * No resolution defined as \<30% ST-segment resolution.