 Heart attacks are a leading cause of death in both men and women in the United States. When a person has a heart attack, blood is unable to reach a certain area of the heart, and if the blood supply is not re-established quickly, that area of the heart can suffer permanent damage. While recovery from a heart attack can be managed through medications and lifestyle changes, these treatments can not reverse the original damage to the heart. Current research is focusing on the development of cell-based therapies using stem cells to repair organs that have been irreversibly damaged by disease. A specific form of stem cells, called adult mesenchymal stem cells MSCs, has shown promise for heart repair. This study will evaluate the safety and effectiveness of injecting MSCs into the heart to repair and restore heart function in people who have had a heart attack and who are having heart surgery for coronary artery bypass grafting CABG. 