Researchers today unveiled the latest clinical trial results from a feasibility study of St. Jude Medical’s (NYSE:STJ) Nanostim lead-free implantable pacemaker, reporting that the device performs on par with traditional devices at 1 year.
In an overseas study of 32 heart failure patients, Nanostim was still going strong at 12 months with no instances of infection, no failure to pace, no mechanical failures or early battery depletion and no device migration, according to results presented today by lead author Dr. Vivek Reddy at Heart Rhythm 2014, the Heart Rhythm Society’s 35th Annual Scientific Sessions.
The findings mark the first 1-year results for Nanostim, a lead-free pacemaker smaller than a AAA battery that sits entirely within the heart. In the LEADLESS clinical trial clinicians placed the device via catheter in an average of about 30 minutes, with patients requiring hospital stays of less than 2 days following implant, Reddy noted.
The Nanostim implant boasts a battery life of between 9 to 19 years, an important consideration for an implant that may not be so easy to extract and replace with a new one. Vivek and his team were able to extract the Nanostim device shortly after surgery, but it’s not clear yet how the body will interact with the implant in the long term.
"Will this device endothelialize all the way up so it’s impossible to grab the back end?" Vivek said. "The real answer is we’re going to know 10 years from now when we start removing these devices."
Researchers have successfully retrieved Nanostim in animal models out to 6 months, and the procedure was a relatively easy one, taking about 5 minutes to capture and remove the implant, Reddy noted.
Alternatively, clinicians could may simply implant a new Nanostim alongside the old one.
"We know it’s technically feasible," Reddy said. "How practical is it? Well, the device occupies 1 cc, so the displacement is only 1cc. It’s not impractical to think about putting 1 or 2 or 3 of these devices into the patient."
The technology is a major departure from standard pacemakers, which rely on leads to transmit pulses from a generator to the heart. Leads have long been cardiac rhythm therapy’s "weakest link," having been the subject of several major recalls in recent years.
St. Jude is leading the charge for lead-less pacemakers with its Nanostim device, which it acquired last year. Physicians at today’s conference agreed that lead-free is an important revolution for heart rhythm management.
"I’m actually personally very interested in some of these concepts of leadless pacing. We’ve all seen, as practicing electrophysiologists and cardiologists, so many lead issues," said Cooper University Hospital Electrophysiology & Arrhythmia Services Director Dr. Andrea Russo during a morning panel ahead of the late-breaking presentation. "This is going to be the future of what we’re doing down the line."
"I do think it will change clinical practice," she added.
In addition to the LEADLESS feasibility study, which is no longer enrolling patients, St. Jude is currently in the middle of a 667-patient investigational device exemption trial in the U.S. and a 1,000-patient European post-approval study.
St. Jude acquired Nanostim last year after purchasing a stake in May 2011 that included an exclusive option to acquire the Milpitas, Calif.-based company.
*Aubrie Johnson contributed to this report.