Subjects with ST-elevation myocardial infarction will be randomized, to one of the following: abciximab infusion with the ClearWay coronary catheter (C), standard abciximab infusion (A), thrombectomy followed by abciximab infusion with the ClearWay catheter (T+C), or thrombectomy followed by standard abciximab infusion (T+A). The primary objective is to demonstrate that abciximab infusion with the ClearWay catheter with or without manual thrombus aspiration (groups C or T+C) will result in a significant reduction of intra-stent thrombus formations when compared to intravenous or intracoronary abciximab with or without thrombectomy (groups A or T+A). The primary endpoint will be the number of cross sections with thrombus area >10% immediately after stent implantation as assessed with OCT. Additional angiographic, ECG, and clinical endpoints will be collected and adjudicated. This trial is currently being registered at ClinicalTrials.gov.

Inclusion Criteria:

• ischemic symptoms must be present at rest and last for at least 10 minutes,
• within 6 hours from onset of chest pain,
• ECG changes will be persistent ST-segment elevation or new-onset left bundle branch block,
• cardiac markers can be either in the normal range or elevated (troponin I or T and/or creatine kinase-myocardial band upper limit of normal for the local laboratory assay),
• coronary angiogram must be obtained within 6 hours from onset of symptom,
• the culprit artery must be identified in a native vessel and must show a significant lesion indicative of local thrombosis with TIMI flow 0-2
• patients must have signed the informed consent form prior to performance of trial-related procedures.

Exclusion Criteria:

• baseline TIMI flow 3,
• tortuosity of coronary vessels that may prevent negotiation of target lesions with the devices that are required by the protocol,
• myocardial ischemia precipitated by a condition other than atherosclerotic coronary artery disease (e.g. arrhythmia, severe anemia, hypoxia, thyrotoxicosis, cocaine, severe valvular disease or hypotension),
• use of a fibrinolytic agent within 14 days prior to randomization,
• use of abciximab or any other glycoprotein IIb/IIIa inhibitor within 30 days prior to randomization,
• suspected active internal bleeding or history of hemorrhahagic diathesis,
• major surgery, biopsy of a parenchymal organ, eye surgery, or serious trauma within 6 weeks prior to randomization,
• gastrointestinal or genitourinary bleeding of clinical significance within 6 weeks prior to randomization,
• history of cerebrovascular accident (CVA) or transient ischemic attack within the previous 2 years or any CVA with a residual neurological deficit,
• administration of oral anticoagulants within 7 days prior to randomization unless prothrombin time ≤1.2 times control (or international normalized ratio ≤1.4),
• ongoing treatment with oral anticoagulant,
• known current platelet count less than 100.000 cells/µL,
• prior known intracranial neoplasm, arteriovenous malformation, aneurysm, or aneurysm repair,
• known allergy to abciximab or other murine proteins,
• known impaired renal function (estimated glomerular filtration rate <60 mL/min),
• coexistent condition associated with a limited life expectancy (e.g. advanced cancer),
• participation in any phase of another clinical research trial involving the evaluation of another investigational drug or device within 30 days prior to randomization, known positive pregnancy test for women of childbearing age.