Infusions of a patient's own cardiac stem cells may reduce scar tissue and promote heart-muscle growth after a heart attack, according to a small safety study. Eduardo Marbán of the Cedars-Sinai Heart Institute in Los Angeles, California, and his colleagues harvested heart cells from 17 heart-attack patients. The cells were used to grow cardiac stem cells that were then reinfused.

Six months later, patients had 28% less scar tissue mass than control patients who did not receive the infusion. Viable heart tissue mass also increased following the treatment, suggesting partial restoration of tissue lost during the heart attack. However, patients showed no improvement in several measurements of heart function, such as the volume pumped out of the left ventricle with each heartbeat.

Lancet http://dx.doi.org/10.1016/S0140-6736(12)60195-0 (2012)