The stem cell trial is one of only a handful that has been cleared by the U.S. Food and Drug Administration (FDA) for heart disease. And because most patients in the UPMC study will eventually receive transplants, the trial represents the first time researchers will be able to examine a human heart treated with stem cells, an opportunity that should help solve some of the mystery as well as resolve scientific debate about just how it is that stem cells work to improve heart function.
Despite advances that have given rise to more effective medical and surgical therapies, including the use of heart assist devices, heart disease continues to exact an economic burden and be a major cause of death in the United States. As such, researchers have looked to the potential of stem cells as a treatment for congestive heart failure and other heart disease. Laboratory studies indicating that a subset of stem cells from bone marrow can generate new heart cells and blood vessels have spawned interest in performing clinical studies. While relatively few such studies have been conducted, and most have been done abroad, preliminary results have shown that blood flow and heart function improve in patients receiving the stem cell therapy.
However, to date, there has been no research in humans that helps explain why such improvements are seen, raising questions that have become the crux of scientific debate about the mechanism and action of these cells once introduced into the heart.
"People have questioned wheth