Abbott has taken a major step in the development of its dual-chamber leadless pacemaker technology, with the company’s first patient receiving two miniaturized, implanted devices within different areas of the heart that synchronize themselves wirelessly to help control the muscle beat by beat.
Traditional pacemaker systems have included a separate power generator placed under the skin near the collarbone, which then connects to the heart with a series of wires. But a new generation of leadless pacemakers, at about one-tenth the size, can be planted inside the heart itself and anchored directly to the muscle wall in a less invasive procedure.
Until now, that option has been limited to pacing just one chamber at a time. Abbott’s implant-to-implant wireless communication system, however, allows one pacemaker to be positioned in the heart’s right ventricle and a second placed above it in the right atrium. This allows electrical signals to be sent to both sets of contracting muscles to help guide a slowing heart’s familiar two-step beat.
"The first-in-human implant of a dual-chamber leadless pacemaker is a major clinical milestone that will open up new possibilities for patients requiring pacing support," study co-chair Daniel Cantillon, research director of cardiac electrophysiology and pacing at the Cleveland Clinic, said in a statement.
According to Abbott, nearly 80% of people who receive a pacemaker need one that can keep up the tempo in both chambers of the right side of the heart, which collects blood from the body’s veins and sends it to the lungs to pick up oxygen.
Dubbed the Aveir DR, the dual-chamber system's clinical launch comes on the heels of the company’s single-chamber implant, the Aveir VR, which cleared a trial late last year and is currently under review at the FDA.
And like the VR before it, the Aveir DR implants are designed to be retrievable by a catheter so that surgeons can replace the device or alter a patient’s therapy if it changes over time. The system is also able to provide real-time heart mapping during placement, so physicians can gauge its effectiveness and reposition it before finishing the procedure.
The single-arm clinical study, which performed its first implantation at Na Homolce Hospital in Prague, Czech Republic, aims to enroll up to 550 international patients with bradycardia and follow their progress for at least one year.
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Other companies, such as Boston Scientific, have taken a modular, two-device approach that combines a leadless pacemaker with an implantable cardioverter defibrillator. A clinical trial signed up its first patients through the Cleveland Clinic late last year and aims to deliver either pacing support when the heart beats too slow or a shock when it beats too fast.
Meanwhile, Medtronic has delivered real-world data on its own leadless pacemaker, the Micra, showing that it led to fewer complications compared to wired cardiac implants over two years, based on an analysis of Medicare claims spanning more than 16,000 people. The original Micra was approved by the FDA in 2016 for patients with atrial fibrillation and other irregular heartbeats. A newer version, the Micra AV, was approved in January 2020.
However, the FDA last year reemphasized the risks posed by leadless devices, such as the possibility of puncturing the heart wall during implantation.
While these cardiac perforations are rare—and appear to happen at a rate similar to that of traditionally wired pacemakers, at about 1%—the agency said that when these cases do occur, the consequences tend to be more severe. The FDA said last November that it has received more than 300 medical device safety reports for the Micra describing a perforation, with more than 90 resulting in death.
In response, Medtronic noted that the company has tracked more than 17,000 patients who have received a Micra device. It reported implantation success rates above 99% and said that the frequency of major complications has remained stable over time.