In mid-2025, a patient at NCH in Naples, Florida, became the first in the United States to receive a simultaneous implantation of the WiSE and Micra leadless heart devices, creating a fully leadless biventricular pacing system to treat a leaky heart valve and asynchronous heart contractions.
Synchronizing Ventricles Without Traditional Wires
Traditional pacemakers rely on a generator placed under the skin with leads threaded through veins directly into the heart. These physical wires can complicate treatments for patients with specific valve issues or high infection risks. To bypass these limitations, Dr. Dinesh Sharma, an electrophysiologist at NCH’s Rooney Heart Institute, led a team treating a patient with a severely leaky heart valve who could not receive conventional pacemaker leads.
The solution combined two distinct technologies. A self-contained Medtronic Micra pacemaker was implanted in the right ventricle to provide baseline pacing. Meanwhile, EBR Systems’ WiSE CRT System was deployed to pace the left ventricle. Unlike standard wired systems, WiSE uses a small electrode inside the left ventricle powered by a separate battery and an ultrasound transmitter implanted in the chest. When Micra paces the right side, WiSE detects the activity and uses ultrasound energy to activate its left-ventricular electrode, restoring coordination to contractions.
Regulatory Milestones and Prior Procedures
The procedure followed a key regulatory clearance. The U.S. Sharma noted that his team previously reported a U.S. first for a totally leadless CRT system in 2022 before WiSE secured formal FDA approval. The mid-2025 operation marked the first time the system was implanted simultaneously with a right-sided leadless pacemaker domestically following that approval.
| Milestone / Event | Timeframe | Details |
|---|---|---|
| Early Leadless Milestone | 2022 | NCH team reports an initial U.S. leadless CRT system procedure prior to full FDA approval. |
| FDA Approval | April 2025 | The FDA approves the WiSE CRT System for patients unable to receive conventional left-ventricle leads. |
| Simultaneous Implantation | Mid-2025 | Naples patient receives the first U.S. simultaneous implant of the WiSE and Micra devices. |
Evolving Pacing Strategies Across International Centers
Leadless pacing technologies continue to develop across various global medical centers addressing complex conduction disorders. In Central Eastern Europe, clinical teams have documented similar evolutions in leadless therapy management. A 95-year-old female underwent implantation of a Micra AV synchronous ventricular leadless pacemaker on May 29, 2020, at the Poznan University of Medical Sciences following lead-dependent infective endocarditis, as detailed in research published by journals.viamedica.pl under the authorship of Agnieszka Katarzyńska-Szymańska, MD, PhD, and colleagues from the 1st Department of Cardiology located at Dluga 1/2, 61–848 Poznań, Poland.
Electrical Parameters and Programming Optimization
Device interrogations and follow-up evaluations at the Poznan University of Medical Sciences recorded basic electrical parameters and pacing events across multiple intervals. At implantation, the QRS amplitude measured 9.9 mV, pacing impedance was 680 ohms, and the pacing threshold stood at 0.50 V per 0.24 ms. At hospital discharge, the QRS amplitude reached 17.2 mV, impedance dropped to 580 ohms, and the threshold remained at 0.50 V per 0.24 ms. During the 1-month follow-up, the QRS amplitude was 15.8 mV, impedance was 780 ohms, and the threshold was 0.38 V per 0.24 ms. At 12 months, the QRS amplitude rose to 19.4 mV, impedance registered 760 ohms, and the threshold was 0.50 V per 0.24 ms. At 18 months, the QRS amplitude exceeded 20 mV, impedance was 710 ohms, and the threshold remained 0.50 V per 0.24 ms. By the 24-month follow-up, the QRS amplitude was 19.6 mV, impedance was 750 ohms, and the pacing threshold was 0.50 V per 0.24 ms. Manual optimization of P-wave detection before discharge increased atrial synchronous ventricular pacing from 47.7% to 92.6%. Adjusting programmable variables, specifically shortening the A3 window end and increasing atrial sensitivity, achieved atrial synchronous ventricular pacing rates of 86.1% at 12 months and 68% at 24 months of follow-up.
