EBR Systems’ WiSE® System Demonstrates Acute QRS Narrowing in 100 US Patients

APHRS presentations highlight real-world results across 31 centers and expert recommendations to support implantation

EBR Systems Press Release 

SUNNYVALE, Calif. -- EBR Systems, Inc., developer of the world’s only left ventricular endocardial pacing (LVEP) system for heart failure, today announced real-world findings from 100 patients across 31 US centers showing a mean acute reduction in QRS duration of 51 milliseconds with WiSE-enabled biventricular pacing.

The findings were presented at the 19th Asia Pacific Heart Rhythm Society Scientific Sessions (APHRS 2026), held October 21–24 in Busan, Korea, alongside expert recommendations for WiSE implantation. Together, the presentations add to the growing commercial experience with WiSE and provide practical insights for physicians treating patients who face barriers to conventional cardiac resynchronization therapy (CRT).

Niraj Varma, MD, PhD, of Cleveland Clinic, presented an analysis of 100 U.S. patients treated following FDA approval. Mean QRS duration, a measure of the time required for electrical activation of the heart’s ventricles, decreased from 190 ± 28 milliseconds with an RV-paced baseline to 139 ± 24 milliseconds with WiSE-enabled biventricular pacing (p<0.0001). The mean reduction was 51 ± 22 milliseconds (26%). No patient showed QRS widening.

The analysis included 62 left ventricular lateral wall and 38 left ventricular septal electrode placements. Mean QRS reduction was equivalent between these locations (52 milliseconds with lateral placement and 49 milliseconds with septal placement, (p=0.51). The acute QRS narrowing observed in both locations may support flexibility in electrode-site selection.

Practical recommendations from experienced implanters

Devi Nair, MD, FACC, FHRS, of St. Bernard's Medical Center and Arrhythmia Research Group in Jonesboro, Arkansas, presented recommendations developed by six electrophysiologists with collective experience spanning more than 100 WiSE implants across U.S. and international practice.

The panel outlined approaches to patient selection, first-case planning, imaging, access strategy, and electrode targeting. Recommendations included completing the first case within two weeks of training, briefly rehearsing on a cadaver or simulator before the case, and reconfirming alignment of the acoustic window scan before electrode delivery.

John McCutcheon, EBR Systems’ President & Chief Executive Officer, said, "For patients who face barriers to conventional CRT, expanding access to resynchronization therapy remains our priority. These findings add to our understanding of WiSE in commercial practice, while the expert recommendations help physicians prepare for implantation. Together, they support our work to bring WiSE to more patients who need another option.”

These presentations build on WiSE’s growing U.S. commercial experience and expand the post-approval evidence shared at the Heart Rhythm Society Annual Meeting in April 2026. For more information about EBR, please visit https://www.ebrsystemsinc.com/.

About EBR Systems

EBR Systems is a cardiac rhythm management company on a clear mission: to transform the lives of people with heart failure by helping physicians deliver optimal cardiac pacing. The WiSE System—the first FDA approved system for leadless left ventricular endocardial pacing (LVEP) in CRT—combines advanced engineering with peer-reviewed clinical evidence to expand access for patients who previously lacked options and to improve outcomes.

About the WiSE Technology

The WiSE System delivers LV endocardial pacing without a transvenous LV lead using targeted ultrasound. A subcutaneous transmitter and battery detect the RV pacing signal and, within milliseconds, emit ultrasound energy that a rice-sized endocardial electrode converts into an electrical pulse—enabling synchronized biventricular pacing. This LVEP approach is engineered for versatility across patient anatomies and is supported by peer-reviewed outcomes from SOLVE-CRT pivotal trial. WiSE is approved for commercial use in the United States and limited to clinical study use outside of the United States.