Team Designs Groundbreaking Leadless Pacemaker for Kids and Adults
Researchers from Children’s Hospital Los Angeles have created a groundbreaking prototype for a new kind of leadless pacemaker designed for both children and adults.
The innovative micropacemaker—created in partnership with USC engineers—would be the first fully leadless system to be placed in the pericardial space surrounding the heart. That would allow the device to be implanted in a minimally invasive way in children and those with congenital heart disease, while also providing a lower-risk leadless pacemaker option for adults.
The proof-of-concept study was published in January in Heart Rhythm. Yaniv Bar-Cohen, MD—Director of Electrophysiology in the Heart Institute at Children’s Hospital Los Angeles—was the first author on the paper and is leading the effort in collaboration with Gerald Loeb, MD, from the USC Viterbi School of Engineering.
Dr. Bar-Cohen shares how this novel pacemaker would work, why it would benefit both children and adults, and what comes next.
How is this design different than current leadless pacemakers?
This would be the first pacemaker that stays entirely out of the heart and has absolutely no leads. Right now there are two FDA-approved leadless pacemakers, and both are delivered through the femoral vein and then placed inside the right heart.
Leadless devices were an important advance because leads are the fail point of pacemakers—they tend to break over time. However, there are significant concerns with placing these leadless pacemakers in young patients (including the very large sheath size in the vein and the potential challenges of removing the devices from inside the heart).
What our team has built is a small leadless pacemaker that does not go through the veins and is put on the outside of the heart instead of the inside. This means it could be used for children and those with congenital heart disease, and it could carry fewer risks for adults as well.
Yaniv Bar-Cohen, MDWe believe our system would be safer than today’s leadless pacemakers while expanding the option of leadless pacing to a much larger number of adults.
How would this pacemaker improve care for children?
It’s about safety but also minimizing surgery. We see several major benefits of this design. The first is that it eliminates the pacing lead, which is the main reason pacemakers fail. Next, the entire system is placed on the outside of the heart, which avoids placing hardware within the bloodstream. Perhaps most importantly, the design allows the pacemaker to be implanted in a minimally invasive way, such that major surgery can be avoided in even small patients.
When adults get a pacemaker, they usually undergo a minimally invasive procedure and can typically go home the same day. But that procedure isn’t possible in many children, either because their veins are too small or because they have a shunt or a hole in their heart. To get a pacemaker, these patients need to have an open-chest surgery, which is a major surgery and involves a few days in the hospital.
We designed a device that is implanted percutaneously. We insert a needle into the pericardial space (the sac around the heart). Once the needle tip is inserted, we can advance a wire and deliver the pacemaker directly into that space through a sheath that looks like a straw. We avoid the veins and the inside of the heart and do so with minimal surgery.
What would be the benefits for adult patients?
We believe our system would be safer than today’s leadless pacemakers while expanding the option of leadless pacing to a much larger number of adults. We see this as revolutionary in that this pericardial leadless design could become the best pacing option for nearly every patient who needs a pacemaker.
Current leadless devices are placed on the inside of the heart, which can cause a perforation when they are implanted. They also theoretically can fall out of place. If that happens, the device could go to the lungs, which would be quite dangerous.
Our design eliminates those risks. Another advantage of our system is that it does not have to go in the right ventricle. It could pace the left ventricle, which is more ideal for optimizing the cardiac squeeze. In addition, more than one device could be put in, whether added in the atrium to allow dual-chamber pacing (as often done in standard pacemakers with leads) or on the other ventricle for biventricular pacing (also known as cardiac resynchronization therapy). All of this is why we see this device as the future of pacemakers.
What was the team’s biggest challenge in creating this device?
We had to figure out: How do you put something on the outside of the heart that will pace without leads—but not move out of place? We worked out a number of novel innovations to solve this, but our final breakthrough came when we added two wire-loop rings that project out from the device after it is deployed. These prevent the device from rolling and moving out of place. We are very excited about our study results.
Yaniv Bar-Cohen, MDWe specifically designed our system to have a similar shape and size to current leadless devices.
What happens next?
We are seeking an industry partner to help us develop this device so it can be tested in humans. We specifically designed our system to have a similar shape and size to current leadless devices. It would be easily compatible with the sophisticated technologies that already go inside pacemakers.
Almost no one is developing pacemakers for kids. I’m extremely excited because our team has built one that has major benefits not only for children, but also for adults. It’s an innovation that could significantly improve care for patients.
