By AMERICAN HEART ASSOCIATION NEWS

A new study shows stem cells from umbilical cord blood may be safe and effective in treating heart failure. This image shows umbilical cord stem cells co-cultured with rat heart cells in vitro. (Courtesy of Cells for Cells)

A new study shows stem cells from umbilical cord blood may be safe and effective in treating heart failure. This image shows umbilical cord stem cells co-cultured with rat heart cells in vitro. (Courtesy of Cells for Cells)

The blood from a baby’s umbilical cord is teeming with stem cells — the “blank slate” cells with the ability to become a muscle cell, a brain cell or any other type of cell in the body.

A team of scientists in Chile have used stem cells from umbilical cords to treat heart failure in a first-of-its-kind study. Findings from the early-phase study were published Tuesday in Circulation Research.

The research team found stem cell infusions were safe and resulted in significant improvement in the heart’s ability to pump blood in the year following treatment. Patients receiving the stem cell therapy also saw their symptoms lessen and quality of life improve.

Fernando Figueroa, M.D., a researcher at the University of the Andes in Santiago who worked on the study, said it was notable that “a single intravenous infusion of these cells would exert long-lasting effects on heart function and quality of life in patients otherwise under optimal treatment, but still facing limitations.”

The impact of stem cell therapy in treating heart failure has been studied for more than a decade. Past studies have focused on hard-to-harvest stem cells taken from bone marrow, but the new study marks the first time umbilical cord-derived stem cells have been tested intravenously in heart failure patients.

Among 30 heart failure patients with reduced ejection fraction, also known as systolic heart failure, half received intravenous infusions of umbilical cord-derived stem cells and half received a placebo. Systolic heart failure occurs when the left ventricle stops contracting normally and the heart loses the ability to push enough blood into circulation.

Using stem cells from umbilical cords has several advantages over using stem cells from bone marrow, Figueroa said.

“This is a minimally invasive procedure. The cell source is accessible, has relatively low processing costs and no ethical conflict,” he said. “It has an extensive track record for safety since it has been used at length in patients with a range of conditions, with no reported adverse effects.”

Figueroa said some scientists believe secretions from the stem cells have regenerative effects on heart tissue. Many scientists also believe the cells are effective in treating heart failure because of the way they decrease damage caused by the immune system.

“While the immune system is important to protect from infectious disease and malignancy, it can also cause damage when activated after an inflammatory event, such as a heart attack, and lead to destruction of cells and tissues,” said pathologist David McKenna, M.D., who has conducted studies on umbilical cord blood and other cellular therapies at the University of Minnesota. McKenna was not involved in the new study.

These types of stem cells, he said, have been shown to modulate or turn down the damaging effects of the immune system by producing protective molecules.

Figueroa said his research group is performing a three-year follow-up to see how patients from the study fare long-term. His research team will also continue to study umbilical cord-derived stem cells as well as stem cells from other sources, such as menstrual fluid.

In the meantime, Figueroa said he is waiting to see the results of two other ongoing studies involving heart disease and umbilical cord-derived stem cells, including one that administers the stem cells through intracoronary injections instead of intravenously.

He said there’s a pressing need for larger, more detailed studies over the course of “many years” to understand the full potential of stem cells — not just in treating heart failure, but other diseases as well.

“We know only part of the picture … the complete mechanism remains to be unraveled,” he said.

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