Cardiology researchers from Children's Hospital Boston hope that a specially treated patch may someday spur human heart cells to regenerate, improving cardiac function in heart attack victims and children with congenital heart problems. The experimental sponge-like patch is soaked in a compound called periostin that is made by the body during fetal development and after injury to bone, muscles, and blood vessels. In preliminary studies, the small patches were placed over damaged heart tissue in rats. Twelve weeks later, the periostin-treated animals had better cardiac pumping ability and less scarring than those who received patches not soaked in the compound.