Miniaturized Pacemaker for Newborns Found Safe and Effective for Up to Two Years

Pacemakers are implantable devices powered by batteries that regulate the heart's rhythm by producing electrical impulses. Traditional pacemakers consist of a generator, wires (leads), and electrodes, which work to control irregular heartbeats. However, these devices are designed for adults, creating difficulties when implanted in small children, who make up approximately 1% of pacemaker recipients. The first issue is that traditional pacemakers are too large for infants, particularly newborns or preterm babies. The second challenge arises from the fact that in adults and older children, the pacemaker wires are typically threaded through veins, but for infants, an open-chest approach is required to directly attach the wire to the heart. Now, a newly developed pediatric pacemaker could provide a better solution for newborns, offering an alternative to the adult-sized devices currently used, which can pose health risks for these young patients. While no pacemakers for infants are yet approved in the U.S., new research published in Circulation: Arrhythmia and Electrophysiology confirms that this miniaturized pacemaker is both safe and effective for up to two years.

Infants may need pacemakers if they are born with congenital heart block, a rare condition where electrical signals do not travel properly through the heart, leading to a slow heart rate. Pacemakers may also be necessary for babies with other rare congenital heart defects. Very small infants often cannot receive permanent pacemakers and instead require multiple temporary pacing wires or other methods until they grow large enough for traditional pacemaker placement. The study conducted by researchers at Children’s National Hospital (Washington, D.C., USg) tested a pacemaker specifically modified for infants, showing it safely and effectively stabilized heart rhythms for up to two years. This research addresses a critical need, potentially reducing hospital stays for affected infants.

Image: The tiny pacemakers can safely stabilize newborns’ hearts for up to two years (Photo courtesy of American Heart Association)

The pediatric pacemaker tested is about one-quarter the size of traditional pacemakers, smaller than an AAA battery. Researchers evaluated the device at 12 pediatric hospitals across the U.S., involving 29 newborns and infants who received the miniature pacemaker. The babies in the study had a median age of 15 days and a median weight of approximately 5 pounds, with many being born prematurely. Some also had congenital heart defects. The devices were successfully implanted, and their stability was confirmed for an average of 325 days, with the longest period being 2.2 years. This smaller pacemaker presents a viable alternative to conventional pacemakers for newborns and could eventually be used for a larger pool of pacemaker patients. Furthermore, it may also be a beneficial option for frail elderly individuals and could serve as a better alternative for certain children and adults.

“The need for an urgent permanent pacemaker in newborns is quite rare, but when needed, it is often an emergency,” said study lead author Charles I. Berul, M.D., a pediatric electrophysiologist at Children's National Hospital. “We are working on a small port that would deliver this pacemaker through a straw-sized tool instead of requiring open chest surgery. This port has been tested in the lab and in small animals.”