Early success of dual-chamber leadless pacemaker suggests big changes could be on the horizon
The first leadless, dual-chamber pacing system performed very well in the Aveir dual-chamber i2i investigational device exemption (IDE) study presented as a late-breaking trial at the Heart Rhythm Society's (HRS) 2023 annual meeting. The large-scale study to assess the world's first dual-chamber, leadless pacemaker system met its three primary endpoints for safety and performance.
The new technology may also open up leadless pacing to a much wider patient population. While leadless pacemakers were seen as a big advance over the past decade, they have been limited to single chamber pacing, which is limited to just 10-20 percent of patients who need a pacemaker. About 80% of patients require dual-chamber pacing. If this new pacing system is cleared by the FDA, it would greatly broaden access to leadless technology for all patients.
The results of this study were simultaneously published in The New England Journal of Medicine.[1] Abbott has shared the data with the U.S. Food and Drug Administration (FDA) as part of its submission for market clearance approval of the new device.
"We exceeded the pre-specified performance goals that were decided in advance with the regulatory authorities. In the electrical performance, we saw more than 95% achievement. The communication between the upper and lower chambers to allow synchronous pacing achieved a 97% success rate. It showed this system is safe and effective and may provide a better solution to allow us to get the benefits of leadless cardiac pacing to a broader population of patients," explained co-principal investigator Daniel Cantillon, MD, formerly with Cleveland Clinic and now the senior VP of global cardiovascular solutions for Masimo.
The pacing system consists of two Aveir transcatheter-delivered pacemakers, one each placed in the upper and lower chambers. The devices are smaller than a AAA battery. Each device is screwed directly into the myocardium to anchor it and to sense and pace the heart without the need for wire leads or a separate pulse generator.
The key development with this system is the use of bi-direction communication between two leadless pacemakers so they can work together to synchronize the beating of both chambers in concert. While most people require pacing and sensing in both the right atrium and the right ventricle, currently available leadless pacing options have been limited to single-chamber ventricular devices because seamless, wireless synchronization of two leadless pacemakers has been a significant technological challenge.
"For the first time we were able to demonstrate the bidirectional, wireless beat-to-beat communication so each device knows what the other is doing, so you have fully synchronous action between the upper and lower chambers of the heart," Cantillon said.
Late-breaking data from the Aveir DR i2i IDE study
The study looked at the primary safety and efficacy endpoints in the first 300 people enrolled across 55 centers in the United States, Canada and Europe. The patients were tracked for three months post-procedure. At the last followup at the end of three months, patients were asked to sit, stand, lay on their right and left sides, and then do a normal and a fast hallway walk. That data was sent to an independent core lab to be evaluated. Results through three-months post-implant showed:
• Physicians demonstrated a 98.3% implant success rate.
• Safety endpoint evaluating freedom from device or procedure complications was achieved.
• More than 97% of people had successful atrio-ventricular (AV) synchrony, so that the upper and lower chambers were beating normally, despite different types of underlying slow heart rhythms.
• The average AV synchrony was more than 95% in each of seven different posture and walking speeds, demonstrating the system will function appropriately during everyday life activities.
"The vast majority of people needing a pacemaker require a dual-chamber pacemaker and would greatly benefit from a leadless device – but we've simply never had that option due to engineering challenges," co-principal investigator Reinoud Knops, MD, PhD, professor of medicine with Amsterdam University Medical Center in the Netherlands, said in a statement. "Data from the AVEIR DR i2i study show that Abbott has designed a groundbreaking technology for seamless communication between two leadless pacemakers, and that AVEIR DR can deliver appropriate therapy safely, opening up a future treatment option for more people with abnormal heart rhythms."
Eliminating the biggest pacemaker infection risks of leads and surgical pockets
"Traditional pacemaker complications effect up to 1 in 6 patients by three years of followup after the original implant. The beauty of leadless pacemakers is that they have neither wires nor surgical access for the pocket. So for the first time, you can provide the full capability of dual chamber pacing support and take advantage of that leadless technology," Cantillon said.
Current pacemaker complications are largely due to the infection of, or breaks in, the wire leads connecting the heart to the pacemaker. The second big source complications are infections or erosions of the surgical pocket that is cut in the side of the patient's chest to insert the pacemaker device.
Infection risk is reintroduced each time a patient needs to have a pacemaker batter replacement. With the leadless pacemakers, Cantillon said these can be snarred with a catheter and removed easily for a device swap when the battery life runs out after
Dave Fornell has covered healthcare for more than 17 years, with a focus in cardiology and radiology. Fornell is a 5-time winner of a Jesse H. Neal Award, the most prestigious editorial honors in the field of specialized journalism. The wins included best technical content, best use of social media and best COVID-19 coverage. Fornell was also a three-time Neal finalist for best range of work by a single author. He produces more than 100 editorial videos each year, most of them interviews with key opinion leaders in medicine. He also writes technical articles, covers key trends, conducts video hospital site visits, and is very involved with social media. E-mail: dfornell@innovatehealthcare.com