Regenerating the heart
Tantalizing findings show that the heart can make new muscle cells.
Fallout from the frightening era of nuclear weapons testing has blown away the long-held notion that the heart can't make new cells, a finding that may someday usher in new therapies for damaged and failing hearts.
For decades, cardiologists and physiologists have worked under the assumption that we are born with all the heart muscle cells we'll ever have, and when one of those valuable heart cells dies, it won't be replaced. That's a bleak view for hardworking cells that contract more than 30 million times a year. It was a perfectly good assumption, based on the best evidence available. Now a creative study shows that the heart does add new cells, although slowly.