CArdiosphere-Derived aUtologous Stem CElls to Reverse ventricUlar dySfunction

The purpose of this study is to determine whether giving cardiosphere-derived stem cells (CDCs) to patients with decreased heart function and/or a large amount of damaged muscle after a heart attack is safe. CDCs are cells grown from small biopsy samples taken from the heart. Giving a patient their own CDCs is an investigational procedure that has been approved by the Food and Drug Administration for this study. In addition to determining whether this treatment is safe, the study will also examine whether it can decrease the amount of heart muscle damage and/or improve heart function after a heart attack. The amount of heart muscle damage and the function of the heart directly affects prognosis (the predicted course of the disease), and the development of heart failure and other complications some patients experience after a heart attack. By way of background, scientists and physicians believed, until just a few years ago, that heart muscle damaged after a heart attack could not be replaced. Recently, however, scientists discovered that new heart muscle can form, or be regenerated, and that this process can be enhanced (or increased) by the administration of large numbers of certain cells isolated from the heart or bone marrow. These cells can be stem cells, or cells derived from stem cells, and they may achieve their benefit by forming new heart muscle cells, becoming heart muscle cells themselves, or releasing substances which increase the ability of already existing stem cells to form new heart muscle. All of the studies conducted so far have been experimental and no cell type is approved for routine clinical care of patients with heart disease. However, studies involving bone marrow stem cells do indicate some small improvement in heart function and one large study demonstrated a decrease in clinical events in the group which received bone marrow cells. Investigators of this study decided to study CDCs because they come from a person's own body, and therefore have no foreign immune antigens which may be rejected. Since the cells come from the person's heart, they are more likely to form heart tissue. In addition, animal studies indicate no safety problems and that these cells are capable of forming heart muscle and blood vessel cells after heart attacks. The investigators are now studying whether the same is true in humans.