Two research teams have shown that stem cells harvested from a patient’s own heart can reverse heart attack damage. Roberto Bolli, director of the division of cardiology at the University of Louisville in Louisville, Ky., and colleagues presented their initial results from an ongoing clinical trial at a national meeting. This trial treated 16 heart attack patients with infusions of cardiac stem cells that had been harvested from their own hearts during bypass surgery. In this experiment, 14 patients had improved cardiac function four months after the procedure, eight of these patients had further improvements a year after infusion, and their heart attack scars shrank. Data from this clinical trial published in the journal The Lancet.
Director of the Cedars-Sinai Heart Institute in Los Angeles, Eduardo Marbán, discussed final results from a different Phase I clinical trial. In this second trial, physicians harvested cardiac tissue using a minimally invasive technique, cultivated the stem cells from the cardiac tissue, and then administered them to 17 study subjects. Marbán said that his team’s cells also shrank heart scars, but also caused increases in living heart muscle in the patients (~600 million new heart cells per subject).
The two studies approach the same question; namely the ability of the heart to regenerate using its own stem cell populations. These two studies, however, use distinct approaches to answer this question. Blocked arteries deprive heart muscle, and if the heart muscle cells are kept without sufficient oxygen for a period time, they will start to die, which is the cause of heart attacks. If sufficient numbers of heart muscle cells die, the heart will not be able to service the needs of the body, and the patient will die from heart failure. In the U.S. alone, it is estimated that about six million people have heart failure. These new results provide hope for these patients, many of whom have been waiting for regenerative therapies to mend damaged heart tissue for more than a decade.
Depending on the Food and Drug Administration’s approach to the new therapy, Marbán said, a product based on his team’s work could be available to patients as soon as 2015 or 2016.