Researchers are using human embryonic stem cells to regrow heart muscle and actually stop the progression of heart failure in rats. Although stems cells injected into rat heart tissue had previously been shown to become muscle tissue, very few had survived. Now a team from the University of Washington has succeeded in turning as many as half the cells into heart muscle, and keeping them alive.
The team used a "pro-survival cocktail" of chemicals along with heat to make the stem cells perform. "Lo and behold, in 100% of the animals we delivered the cells to, we saw grafts," the lead researcher told the Seattle Times. About 10% of the damaged hearts were repaired enough to prevent further heart failure. "The fact that if you can grow human heart muscle back, that prevents heart failure — we didn't know that," he said.