In a small study, 25 patients were either treated with their own heart stem cells or provided with standard care following their heart attacks. In patients who received stem cell treatment, the size of the scar tissue in the heart reduced by around 50%, with no change in the patients who did not receive stem cells. However, after six months there was no difference in heart function (end-diastolic volume, end-systolic volume, and left-ventricular ejection fraction) between the groups. Complications were also reported in four of the patients receiving stem cells compared to only one in the control group.
The research was conducted by Professor Eduardo Marbán, Cedars-Sinai Heart Institute, Los Angeles and colleagues and published in The Lancet.
Commenting on the significance of their research, the authors said: “This discovery challenges the conventional wisdom that, once established, cardiac scarring is permanent and that, once lost, healthy heart muscle cannot be restored."
Professor Bob Graham from the Victor Chang Cardiac Research Institute also commented that, "The positive effects on scar size and viable heart mass reported in the study are encouraging, although it’s curious that these didn't translate into an improvement in contractile function. Clearly larger studies that are powered to look for efficacy are needed. The apparent increase in serious adverse side effects in the treated group is a concern and will have to be carefully monitored in future trials."
For more information:
Intacoronary cardiosphere-derived cells for heart regeneration after myocardial infarction (CADUCEUS): a prospective, randomised phase 1 trial THE LANCET, Early Online Publication (subscription maybe required)
Stem cells used to 'heal' heart attack scars BBC News 14 February 2012
Stem cells reverse heart attack damage COSMOS News 16 February 2012