A human heart is made up of billions of cells, but researchers say fewer than 10,000 are responsible for controlling the heartbeat. Age and disease can lead to problems such as the heart pumping too fast or too slow - and it can even stop completely, in what is known as a cardiac arrest.
A team of [researchers] tried to restore the heart's own ability to dictate the beat by creating new pacemaker cells. They used a virus to infect heart muscle cells with a gene, called Tbx18, which is normally active when pacemaker cells are formed during normal development in an embryo. When heart cells were infected with the virus they became smaller, thin and tapered as they acquired the "distinctive features of pacemaker cells."
When the virus was injected into a region of the hearts of seven guinea pigs, five later had heartbeats which originated from their new pacemaker. [Researchers expect] the same method to work in the human heart as they used a human gene, Tbx18, to generate the effect.
"It opens up the tantalising possibility of using cell therapy to restore normal heart rhythm in people who would otherwise need electronic pacemakers. However, much more research now needs to be done to understand if these findings can help people with heart disease in the future."