One of the challenges of stem cell therapy is to understand the fate of the injected stem cell. By labelling various stem cells with radioisotopes their fate (homing) can be demonstrated. In this study, we will develop and refine the existing techniques of stem cell labelling to various subtypes of stem cells namely- freshly aspirated bone marrow cells, cryopreserved bone marrow cells, g-csf mobilized peripheral blood stem cells and umbilical cord cells. After testing the labelling efficacy and viability, these cells will be injected in to the coronary arteries of patients with myocardial infarction who have undergone a successful revascularization either by angioplasty or thrombolysis. Homing of stem cells will be demonstrated by nuclear scan after the procedure. We are adapting techniques used to label cells for detection of infection and bleeding using nuclear scans for in vivo scanning. Also we are using Technetium instead of FDG which has very little radioactivity allowing us to work with the current cardiac labs with out having to reconstruct the labs with special shielding for radioactive compounds. Real benefit of stem cells then can be explored after demonstrating the proper homing.