Donated cells work as good as own stem cells during heart tissue repair, says a new study published in the Journal of American Medical Association. Researchers say that stem cells derived from donors have the potential of being an "off-the-shelf" therapeutic agent.

"You could have the cells ready to go in the blood bank so when the patient comes in for a therapy - there's no delay. It's also cheaper to make the donor cells and a single marrow donor can supply enough cells to treat as many as 10 people," said Dr. Joshua Hare of the University of Miami, lead author of the study, to ABC News.

The small study involved 30 patients from Miami and Baltimore. All the patients' heart tissue was damaged after a heart attack. They were then divided into two groups; one group receiving own stem cells while the other received stem cells from a healthy donor.

28 percent in the donor stem cell group had an improvement in heart function compared to self-stem cell group. After a year, eight patients in the self-stem cell group and five in the donor-stem cell group suffered a serious cardiac event. Both groups had reported a 33 percent improvement in scar tissue healing.

"The trials so far have very small patient numbers. I think this early work in cardiac stem cells look very promising," said Stefanie Dimmeler, director of the Institute of Cardiovascular Regeneration Center of Molecular Medicine at Johann Wolfgang Goethe University in Frankfurt, Germany, according to Reuters.

Researchers say that the use of donor stem cells can reduce the time taken for treating a damaged heart as these would be more readily available than own stem cells. Also, for older people with certain health complications, using own stem cells may not be a feasible option.

"That opens up an entire new avenue for stem cell therapy, like a sophisticated version of a blood bank," said Dr. Elliott Antman of Harvard-affiliated Brigham and Women's Hospital in Boston, to ABC News.

The study was presented at American Heart Association conference in California.