Randomized Evaluation of Intracoronary Transplantation of Bone Marrow Stem Cells in Myocardial Infarction

Inclusion Criteria: * Patients with acute myocardial infarction (ST elevation in at least 2 leads ≥ 0.2 mV in V1,V2 or V3 or ≥ 0.1 mV in other leads), treated by one of the following procedures: * Acute PCI with stent implantation for acute ST elevation MI for either denovo lesions or in-stent thrombosis * Treatment with thrombolysis followed by PCI with stent implantation. * Acute PCI / stent implantation has been successful (residual stenosis visually \< 30% and TIMI flow ≥ 2). * At the time of inclusion (≥ 1 day post PCI) patient does no longer require i.v. catecholamines or mechanical hemodynamic support (aortic balloon pump) * Significant regional wall motion abnormality on echocardiography at the time of acute PCI (ejection fraction ≤ 50% on visual estimation). * Maximal cardiac troponin elevation ≥ 4 (measured at 37° C) * Age 18 - 80 Years * Written informed consent Exclusion Criteria: * Regional wall motion abnormality outside the area involved in the index acute myocardial infarction. * Need to acutely revascularize additional vessels, outside the infarct artery. * Arteriovenous malformations or aneurysms * Active infection or fever or diarrhea within last 4 weeks. * Chronic inflammatory disease * HIV infection or active hepatitis * Neoplastic disease without documented remission within the past 5 years. * Cerebrovascular insult within 3 months * Impaired renal function (creatinine \> 2 mg/dl) at the time of cell therapy * Significant liver disease (GOT \> 2x upper limit) or spontaneous INR \> 1.5) * Anemia (hemoglobin \< 8.5 g/dl) * Platelet count \< 100,000/µl * Hypersplenism * History of bleeding disorder * Gastrointestinal bleeding within 3 months * Major surgical procedure or trauma within 2 months * Uncontrolled hypertension * Pregnancy * Mental retardation * Previously performed stem / mononuclear cell therapy * Participation in another clinical trial within the last 30 days