Wireless Pacemaker Shows Promise in Early Study
Device implanted directly in the heart, but questions remain about long-term use, safety
WebMD News Archive
By Randy Dotinga
THURSDAY, May 9 (HealthDay News) -- Scientists report positive results in early testing of a wireless pacemaker that's placed in the heart instead of being connected to it via wires from the upper chest.
There are still many questions regarding the pacemaker, produced by Nanostim Inc. It's only been implanted in a few dozen people who were studied for a matter of months, limiting information about its long-term use and safety. It's also not clear when the pacemaker may be publicly available, and its cost is unknown. And the existing version of the device won't work for most pacemaker patients because it lacks some key features.
Still, a new company-funded study shows that "this is now a possibility" that could reduce infections and the severity of pacemaker surgery, said study author Dr. Vivek Reddy, director of the Cardiac Arrhythmia Service at Mount Sinai Hospital in New York City. "This is going to be the future," he said.
Pacemakers zap the heart with low levels of electricity when the heartbeat becomes too fast, too slow or too irregular. Some are combined with defibrillators, which give the heart a major jolt when needed.
Currently, pacemakers include two components: a battery-powered generator that produces the electrical "prompts" that the wires deliver to the heart when needed, Reddy said. These wires can break or become infected, he explained, making the idea of a wire-free pacemaker appealing.
The new pacemaker is about the size of a AAA battery and provides jolts to one chamber of the heart, Reddy said. Most people with pacemakers require jolts to both chambers, so the pacemaker in its current form wouldn't work for them.
In the new study, researchers implanted the pacemaker in 32 people for the first time through a puncture in the skin; in 10 patients, they had to reposition it. The researchers reported positive results at up to three months. However, one patient died of a stroke while convalescing after suffering a heart injury during implantation and another had the pacemaker replaced with a defibrillator.