Studies on animals and humans have shown that certain adult stem cells taken from the bone marrow have the potential to influence heart muscle and blood vessel growth.
The new research was the first to demonstrate this by following up two sets of patients in a randomised trial. The first convincing evidence that failing hearts can be repaired using bone marrow stem cells has been produced by a clinical trial, it was revealed yesterday.
US scientists compared two groups of heart bypass patients, with patients in one group treated with stem cells taken from their own hip bones.
Six months later the hearts of the stem cell group were pumping out more blood than those of patients who had bypass surgery alone. Professor Robert Kormos, who heads the University of Pittsburgh team which led the international study, said today: "These results encourage us to aggressively pursue cellular therapies as an option for congestive heart failure, reports smh.com.au
He and other researchers warned, however, that so far the technique remained purely experimental and needed to be assessed on a far wider scale before being made generally available. The 20 patients in the study were all chosen because their hearts were failing so badly that they urgently needed cardiac bypass operations.
During the operations, 10 of the patients had bone marrow taken from their hips. Stem cells extracted from each patient’s marrow were then injected into their hearts wherever the doctors could find muscle damage. The other 10 patients were given the bypass operation but no stem cells.
In several cases their hearts became almost as powerful as in a person with no heart disease. Patel said: "Stem cell transplantation led to significant improvement in cardiac function in these patients, compared with the 10 control patients who had just the bypass operations."
Coronary heart disease is the leading single cause of death in Britain, killing about 125,000 people a year.
According to BBC the team are continuing the trial with 40 patients, while a separate one, looking at patients with inoperable heart failure is under way.
Belinda Linden, Head of Medical Information for the British Heart Foundation, said: "This is particularly significant as the incidence of heart failure is increasing. "Most current treatments are aimed at relieving the symptoms; if we can actually repair the heart itself this will be a signficant advancement.
"However, it must be remembered that this treatment is still experimental and we need to know much more about the way that stem cells work to be able to understand how they provide their beneficial effect."