This procedure, described today in the Science Translational Medicine, restored normal heart rates for two weeks in pigs that usually rely on mechanical pacemakers. We have been able for the first time to create a biological pacemaker using minimally invasive methods and to show that the new pacemaker suffices to support the demands of daily life, Eduardo Marbán, a cardiologist at the Cedars-Sinai Heart Institute and lead author of the study, told the press yesterday. The approach is practical, added Eugenio Cingolani, a cardiogeneticist also at Cedars-Sinai and a co-author of the study, because no open-heart surgery is required to inject this gene. We were able to get the biological pacemaker to turn on within 48 hours, Marbán said.