Scott Buzby , 2025-05-01 15:13:00
Key takeaways:
- Left bundle branch pacing was achieved for the first time via leadless pacemaker.
- Implantation failure rate was high and left bundle branch area pacing capture was achieved in just 50%.
In a first-in-human study, researchers achieved left bundle branch area pacing with a leadless pacemaker in a handful of patients already indicated for pacemaker implant, a speaker reported.
The first-in-human results of left bundle branch (LBB) area pacing via leadless pacemaker with conduction system pacing (Aveir CSP, Abbott) were presented at Heart Rhythm 2025 and simultaneously published in HeartRhythm.
“Leadless pacing has demonstrated significant benefit to patients. Patients like not having a scar or a device that they can feel. But one of the limitations to current leadless pacemakers is they are limited to ventricular pacing in the [right ventricle] and they cannot perform conduction system pacing or left bundle branch area pacing,” Vivek Y. Reddy, MD, director of cardiac arrhythmia services at Mount Sinai Hospital and the Mount Sinai Health System and the Leona M. and Harry B. Helmsley Charitable Trust Professor of Medicine in Cardiac Electrophysiology at Icahn School of Medicine at Mount Sinai, said during a presentation. “There is a novel helix-based leadless pacemaker that was developed for left bundle area pacing and combined the advantages of leadless pacing with that of conduction system pacing.”
The present device has not yet been FDA approved, but Abbott announced in December that the agency granted the product a breakthrough device designation, which is intended to expedite the development and review of devices intended to treat a serious condition in which preliminary clinical evidence indicates potentially substantial improvement over available devices.
For implantation, the device is introduced through the right jugular vein, passing through the tricuspid valve, and features a helix to allow fixation in the mid interventricular septum.
Once implanted, the researchers evaluated the trial’s primary performance endpoint, including device capture threshold, impedance and sensed R-wave amplitude, while still attached to its delivery catheter.
After bidirectional communication of these measurements with the programmer system, the researchers removed the device and proceeded with the patients’ scheduled implant of a de novo single-chamber or dual-chamber leadless pacemaker.
The primary safety endpoint was freedom from serious adverse device-related events at 1 month.
Fourteen patients were enrolled at Na Homolce Hospital in Prague (mean age, 69 years; 71% men). The device was successfully implanted in 10 patients. Implantation was not attempted in two patients due to small atrium or limited maneuverability. In two other patients, implantation was attempted but failed due to inadequate positioning.
The average procedure time was 48 minutes. Average fluoroscopy time was 16 minutes.
Two-thirds of participants were indicated for pacemaker implant due to sinus node dysfunction, whereas the remainder had atrioventricular block, conduction disorders with 1:1 atrioventricular conduction and vasovagal syncope.
The researchers reported that electrical parameters at the final implant locations were acceptable, with a mean pacing threshold of 1.2 V at 0.4 milliseconds, R-wave amplitude of 10.2 mV and impedance of 373 ohms.
LBB area pacing capture was observed in five patients, of which one was segmented to direct capture of the LBB and four to left ventricular septal pacing, according to the presentation.
Deep septal pacing was observed in three additional patients, whereas right ventricular septal pacing was observed in two patients.
Freedom from serious device-related adverse events was 85.7% at 1 month. The two serious adverse events reported were worsening tricuspid valve regurgitation and access-site hematoma.
Vivek Y. Reddy
“In this proof-of-principle first-in-human study, this conduction system pacing device with an extendable distal electrode was able to achieve left bundle branch area pacing in some patients, and it did demonstrate acceptable safety and performance,” Reddy said during the presentation. “This provides the basis for further studies in a chronic setting to see how well this works in patients requiring left bundle area pacing.”
References:
Sources/Disclosures
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Reddy VY, et al. Late-breaking clinical trials and science: Clinical innovations (non-ACE). Presented at: Heart Rhythm 2025; April 24-27, 2025; San Diego.
Disclosures:
The study was funded by Abbott. Reddy reports numerous financial ties with pharmaceutical and device companies, including consulting and/or receiving grant support from Abbott.
