Ischemic cardiomyopathy: Pathological Findings In A Case Of Stem Cell Implantation

摘要

The term “regenerative medicine” is a multidisciplinary field involving molecular and cell biologist, embryologist, pathologist, clinicians, bioengineers, and not to exclude ethicists. Early clinical studies, so for have indicate that, a stem cell implantation is feasible and has beneficial effect on infarcted heart. When compared to death of donor hearts for transplantation, complications associated with immunosupression, long-term failure of transplanted organs with high morbidity and mortality rates associated with myocardial infarction, stem cells scores over organ transplant. Most of the trials to date assessed cardiac function at 4-6 months after treatment and long-term outcome have not yet been described. Here in we present histopathological findings in explanted heart in a 50-year-old male patient who had received stem cell therapy for chronic ischemic heart disease. Introduction Stem cell therapy is emerging as a potential therapy for infarcted heart. There is growing interest in clinical cardiology treating patients with myocardial infarction or cardiac failure with stem cells. Cardiac experiments, mainly with adult homologous stem cells, have proved that this therapy is safe and may improve myocardial vascularization and pump function.1 Stem cells are multipotent, undifferentiated cells capable of multiplication and differentiation. Four categories of stem cells have been examined for their ability to promote cardiac repair: bone marrow derived/circulating progenitor cells (BMPCs) and their subpopulation, skeletal myoblasts (SM), embryonic stem cells (ESCs) and resident cardiac stem (or cardiomyocyte progenetor) cells (CMPCs).2 Skeletal muscle cells and BMPCs are being used in clinical trials mainly because these cell types are potentially autologous. ESCs are at present the major heterologous source of cells being considered and ethically the most sensitive as their derivation requires the destruction of early human embryos. Different techniques and routes of administering stem cells have been advocated. Although intramyocardial injection process is simple and can be performed by direct inspection of the potential target zones during cardiac surgery, it is associated with intraoperative and postoperative risks.3 Intracoronary injection has advantage because it can deliver the maximum concentration of cells to the site of infarct and peri-infarct tissue during the first passage. However, in successive days intravenous administration of stem cells will be an attractive and practical mode of delivery. There exists always a risk of micro vascular obliteration and of poor therapeutic efficiency if the stem cells are to cross the coronary wall and migrate extravascularly- especially when targeting a territory supplied by occluded coronary arteries.1 While experimental studies and early phase clinical trials tend to support that stem cell therapy enhances cardiac repair by improving myocardial vascularization and pump function. Present consensus is that stem cell have therapeutic benefit, but this is not based on the ability of these cells to Tran differentiate into cardiac myocytes. There are still several key issues still needs to be addressed like; the optimal type of donor cells in relation to the clinical profile, the mechanism by which cell engraftment improves cardiac function, development of less invasive cell delivery techniques and relevance to non-ischemic heart failure.2 Case Report He was a 50-year-old male, diabetic since 18 years old, hypertensive, and a known case of coronary artery disease. This patient had under gone coronary artery bypass graft (CABG) for triple vessel disease, with 4 grafts in 2005 in our hospital. Later, he was admitted with repeated signs of ischemia. He was offered a choice of stem cell therapy in 2006. He subsequently under went stem cell therapy in 2006. Autologous stem cells were harvested from bone marrow. Stem cell injection was done through left coronary artery, right coronary