The company that learned to pace a failing heart without a wire - using a pulse of ultrasound and an electrode the size of a grain of rice.
For half a century, keeping a struggling heart in rhythm has meant threading an insulated wire - a "lead" - through a vein and into the heart. The lead is also the weak link: it can dislodge, fracture, scar or simply fail to reach the spot a physician needs. EBR Systems, founded in Silicon Valley in 2003, built its entire existence around one contrarian question - what if the pacing signal could travel without a wire at all?
The answer is the WiSE System, short for Wireless Stimulation Endocardially. It is, by the FDA's own designation, the world's first and only leadless left ventricular endocardial pacing (LVEP) device for cardiac resynchronization therapy. Instead of a lead, a receiver-electrode roughly the size of a cooked grain of rice is implanted directly inside the left ventricle. A separate transmitter, placed under the skin, fires a pulse of ultrasound; the electrode converts that sound energy into the electrical stimulus that paces the heart.
The device does not try to replace a patient's pacemaker or defibrillator. It works alongside them - detecting when the right ventricle is paced and answering, in near-instant sync, from inside the left. That co-existence is deliberate. EBR set out to serve the patients conventional cardiac resynchronization therapy leaves behind: those who did not respond, whose coronary sinus lead failed, or who cannot safely receive another one.
It took more than two decades of engineering and clinical trials to get there. In April 2025, the FDA approved the WiSE System. The first U.S. patients were implanted commercially the same year. For a company that spent 22 years on a single idea, the approval was less a finish line than the moment the idea finally met the people it was built for.
The WiSE System converts acoustic energy into a pacing pulse. Here is the sequence, from an ordinary heartbeat to a resynchronized one.
The patient's own pacemaker or ICD paces the right ventricle as usual.
A subcutaneous transmitter senses that beat and fires a focused ultrasound pulse.
The rice-grain electrode inside the left ventricle turns sound energy into electricity.
The left ventricle contracts in sync with the right - resynchronizing the heart.
A meaningful share of heart failure patients do not improve on conventional CRT. The WiSE System offers left ventricular pacing from a different location - inside the chamber.
Coronary sinus leads can dislodge or fracture, and some anatomies can't accept one at all. A leadless electrode sidesteps that failure point entirely.
Adding a lead to an existing device raises infection and complication risk. WiSE adds pacing capability without adding another wire.
Pacing from inside the ventricle is more physiologic than the outside-vein approach conventional CRT relies on.
Leadless pacemakers like Micra and Aveir exist, but WiSE is the only approved leadless left ventricular endocardial CRT device.
It complements a patient's existing device rather than requiring a full system swap.
"This Breakthrough Device Designation underscores the need for novel solutions for heart failure patients, who have few options today."
In 2023, EBR's pivotal SOLVE-CRT study met its primary safety and efficacy endpoints so convincingly that an independent monitoring board recommended halting it early for success - a rare event in medical devices.
Reduction in left ventricular end-systolic volume, a key measure of reverse remodeling in the failing heart (p = 0.003).
Freedom from Type I complications in the trial population (p < 0.001), supporting the device's safety profile.
EBR is targeting a US$3.6 billion addressable market, built from three groups of patients that conventional therapy under-serves.
Bars illustrate the relative categories EBR has described; not audited financial figures.
EBR is a medical device manufacturer. It sells the WiSE System to hospitals and cardiac electrophysiology centers, where physicians implant it. In the U.S., adoption is supported by Medicare's New Technology Add-on Payment (NTAP) and transitional pass-through (TPT) reimbursement, secured in October 2025. The company is publicly traded on the Australian Securities Exchange under the ticker EBR and funds its commercial rollout through capital raises.
EBR was formed in Silicon Valley in 2003 by an unusual trio whose skills had to overlap for the concept to work:
In June 2019, veteran medtech executive John McCutcheon joined as President and CEO to steer the company through its pivotal trial, FDA approval and commercial launch.
EBR Systems forms to develop wireless cardiac stimulation and eliminate pacing leads.
The company closes US$30M in financing; John McCutcheon joins as President and CEO.
EBR Systems goes public on the Australian Securities Exchange under the ticker EBR.
The pivotal trial meets its endpoints early, clearing the path to FDA submission.
The WiSE System is approved, first U.S. patients implanted, and Medicare reimbursement secured.
Product demonstrations, physician interviews and company updates are published on EBR's site and YouTube search.