Stem cells function within the body as “master cells” and are unspecialized cells that have the capacity to renew themselves through the process of cell division, for a long period of time. Under physiological or experimental conditions stem cells can be forced to become specialized cells like heart muscle cells or the insulin-producing pancreatic cells.
In modern medicine, in the past few years scientists have proved that stem cells therapy has a huge potential in the treatment of various diseases including ischemic heart disease.
Stem cells can be embryonic, obtained from embryos and adult stem cells that can be found among the differentiated cells of an organ or tissue and have the role of repairing and reconstructing damaged areas of that tissue. In the adult body stem cells can be found in the brain, blood vessels, bone marrow, skin, liver and the skeletal muscles.
For many years scientists believed that adult stem cells are only able to generate cell types similar to those of the tissue where they reside, moreover, during the last years has been discovered that stem cells can generate other cell types of different tissue like brain, pancreatic or heart cells, phenomenon named plasticity.
In the future, stem cells therapy can become one of the most important treatments for ischemic heart disease or myocardial ischemia, a disease caused by coronary artery disease and characterized by low blood supply to the heart muscle. Scientists have recently discovered that stem cells transplant could have a high value in ischemic heart disease therapy because it has been proved that heart tissues have high potential of regeneration.
In spite of the fact that the treatment wasn’t applied to a large scale and it’s still in an experimental stage, clinical studies show that intercoronary transpalntations of bone marrow stem cells to a patient who suffers from cronic or acute ischemic heart disease in most cases gradually improves the function and the regional myocardial perfusion in the left ventricle, moreover notable complications haven’t been described and due to the low morbidity among the patients who have received the treatment, we can say that it can be a revolutionary alternative in ischemic heart disease treatment.
The treatment of ischemic heart disease focuses both on revascularization techniques and on medical therapy to improve the function of cardiac myocytes that aren’t affected by the disease.
Stem cells therapy, in the form of autologous cell transplantation, has been researched as a technique in the myocardium regeneration and ventricular modification and remodeling post heart attack. It is believed that in normal conditions after a stroke a large number of hematopoietic stem cells are released in the circulatory system. They are then engrafted into the damaged heart area. In spite of the fact that stem cells don’t have the result of an effective regeneration of the myocardium, it is expected that this process could actually improve cardiac regeneration and remodeling.
The use of granulocyte colony stimulating factor (or GCSF) infusions has been studied and it is believed that it helps at the acceleration of hematopoietic stem cells release rate. As alternative, stem cells obtained in a laboratory can be infused into the patient’s heart.
In experimental,animal models, embryonic stem cells have been transplanted into the damaged heart; the transplant being followed by cardiac regeneration the experiment was considered a success. Now, among the scientists worldwide the attention has turned towards adapting those techniques to humans. In humans, harvested skeletal myoblasts, obtained from a muscle biopsy, hematopoietic stem cells, harvested bone marrow stem cells, and, peripheral blood, have been studied. Harvested stem cells, transplanted by various methods, are used as adjuncts to coronary artery bypass surgery. They can be directly injected into the necrotic myocardium, or into a coronary sinus or artery. Through unknown mechanisms, or at this moment not very well understood, circulating hemotopoeitic stem cells can have some kind of natural homing ability to the necrotic myocardium. In the future, scientists are investigating the possibility of their noninvasive systemic administration.
Right now, the procedure is only experimental and there aren’t specific codes for it, either to describe the laboratory component necessary to process the harvested autologous cells, or the implantation procedure. The implantation can be an added component of a scheduled coronary artery bypass graft (CABG), or it can be performed as a unique indication for a cardiac catheterization procedure.
In the studies have emerged a lot of variable such as the time of the post infraction treatment or the cells injected types. Crucial information about the appropriate patient population, about the effective times of the treatment, or about the most effective cell types is not yet available. The European Society of Cardiology labels autologous stem/progenitor cell therapy as “not at a stage to be used in routine clinical practice.” In spite of the progress in this field, scientists have to admit that autologous cell therapy in ischemic heart disease treatment is only investigational.