Can stem cells repair a broken heart?

Well, I doubt stem cells will have much influence on how hurt you are by the dissolution of a relationship. That said, it seems that new research, discussed in news articles on the Nature (Nature) and BBC (BBC news) websites (the research article is presented in Nature also) indicated that dormant heart stem cells can be woken up and set to work following a heart attack. Cardiomyocytes (heart cells) are damaged during a heart attack. A normal heart has limited repair mechanisms and once damaged the cells will inhibit the proper functioning of the heart, which could ultimately lead to further, and possibly fatal, attacks.
The research that has just been published, and previous research (referenced in the Nature news piece) indicate that a particular protein can help the natural heart stem cells generate new blood supply and muscle tissue, repairing sites that have been damaged. It seems there is a bit of debate about how effective the protein would be in humans and whether a preventative approach for high risk patients or injecting the protein following heart attack would have the greatest effect. Still, the results are very interesting and show promise of making a significant difference to heart patients in the future.