(SACRAMENTO, Calif.) UC Davis researchers have successfully used a custom designed protein and gene delivery system to restore normal heart rhythms in pigs with electronic pacemakers, reducing their dependence on implanted devices. This work suggests that scientists are one step closer to making bioengineering a reality in treating the more than 2.2 million Americans affected by irregular heartbeats.
The UC Davis study, which was co-authored by an international team that included scientists from the University of Hong Kong and Johns Hopkins University, is published in the current issue of the journal Circulation, (which is available online and will appear in print on September 5). The same issue also includes a similar but independent research effort by scientists from Columbia University and State University of New York at Stony Brook.
"Our study offers positive and direct evidence in living models that bioengineered cells can replace the electronic pacemaker," said Ronald Li, who leads the research team and is an associate professor of cell biology and human anatomy at the UC Davis School of Medicine. More than 250,000 people in the United States get artificial pacemakers implanted each year. Researchers believe this biological approach would provide a more permanent, reliable and less invasive alternative to implanted electronic devices. "Our hope is to one day replace electronic pacemakers in people," Li said.
Li and his colleagues have been working for years to develop biological alternatives to drugs and electronic devices for treating heart arrhythmias heartbeats that are irregular in rhythm, rate or sequence. The sinoatrial (SA) node, a patch of cells called the pacemaker, generates cardiac rhythms for coordinated contractions and blood pumping. Malfunctions due to aging or diseases can lead to a range of potentially lethal arrhythmias, such as slow heart rates or rhythms called bradycardias.