Far-field sensing for the Heart
Biotronik's Leadless Pacemaker Detects Atrial Signals
Goodbye to the pacemaker syndrome—synchronized pacing even without a lead. Using far-field sensing, Biotronik’s leadless LivIQ pacemaker detects the electrical signal from the atrium directly through the heart tissue and paces the ventricle accordingly. The first clinical trials have begun.
The cardiac patient is 70 years old, his venous status is fragile, and he has a long history of infections. Now he’s developed an AV block, a type of heart rhythm disorder. The cardiologist ponders: Should I implant an electrode? Where? With what risk? It’s a decision path that doctors are familiar with—and for which, in addition to traditional pacemakers, they’ve known a new, lower-risk solution for a few years now: leadless pacemakers.
About a decade ago, Medtronic proved with the Micra that an implant the size of a vitamin capsule can provide reliable stimulation—without a pocket, without leads, anchored directly in the ventricle. Implanted over 100,000 times, clinically validated on a broad scale. The concept works.
And yet, there is still an unresolved issue. Because a pacemaker that stimulates only the ventricle, without sensing the atrium, stimulates at a rate that deviates from the natural rhythm. The result can be pacemaker syndrome: a drop in performance, dizziness, and discomfort. Medtronic has addressed this problem with the Micra AV. For its new LivIQ with DX technology, Biotronik is taking a novel technical approach that may promise greater precision.
The Core Problem: the Atrium
AV synchrony—the coordinated coordination between the atrium and ventricle—is at the heart of physiologically correct cardiac function. In conventional dual-chamber systems, an atrial lead establishes this connection. In the leadless approach, this lead is eliminated. The question, then, is: How does an implant located solely in the ventricle detect what the atrium is doing?
Medtronic solves this with an accelerometer. The Micra AV measures the mechanical wall motion of the ventricle triggered by atrial contraction—and uses this to determine the atrial rhythm. Clinically effective and battery-efficient, the AV2 has a battery life of over 15 years.
Biotronik is now relying on electrical far-field sensing. The implant directly detects the atrial P-wave signal, which propagates through the heart tissue as an electrical far-field signal—a concept closer to traditional ECG-based sensing. According to the manufacturer, LivIQ is thus the world’s first intracardiac pacemaker to enable AV-synchronized pacing via atrial far-field signals—not only at rest but also during physical exertion. The benefit the Berlin-based manufacturer expects from this: higher specificity in clinical situations where the mechanical signal is weak or ambiguous—during episodes of atrial fibrillation, tachycardic phases, or anatomical variations.
There is also another design requirement: the system must provide reliable frequency adaptation without compromising battery life—a key indicator for developers of how the sensing concept’s energy management is designed. »LivIQ combines two key advancements: a particularly easy-to-use catheter design and a new sensing concept that supports therapy in even more clinical situations,« says Dr. Andreas Hecker, CTO of Biotronik. Whether this approach is clinically superior to mechanical sensing remains to be seen.
From First Implantation to a Global Study
It is precisely this evidence that is now being gathered. The first LivIQ implantations have been performed—including at Kokura Memorial Hospital in Kitakyushu and at the NCVC in Osaka. In March 2026, Biotronik launched the global regulatory trial BIO-LivIQ: 325 patients, up to 60 centers worldwide, prospective design. The endpoints include pacing performance, safety, AV synchrony behavior, and quality of life—the goal is to provide regulatory evidence for global approval applications. The package also includes a specially developed implantation catheter, designed for precise placement and good maneuverability for the operating physicians.
»I am pleased that a compelling option for an electrode-free single-chamber device is emerging, one that promises reliable AV synchrony and long-term performance,« commented Dr. Kengo Kusano, principal investigator at the NCVC Osaka, regarding the LivIQ system.
The leadless pacemaker embodies a clear system philosophy at Biotronik: reducing complexity without compromising diagnostic or therapeutic quality. The technological foundation for this is DX sensor technology—which captures atrial and ventricular information from a minimized system configuration. Recent data confirms that this principle holds up clinically: The results of the CRT-NEXT study presented at ACC 2026 show that a two-electrode system does not necessarily mean lower therapeutic quality—and can significantly reduce the complication rate.
For developers in cardiac device technology, the direction of the future is becoming clear: far-field sensing algorithms with high selectivity, miniaturized enclosures with optimized energy budgets, precisely controllable catheter systems, and robust telemetry for remote monitoring. The competition between the two approaches—mechanical versus electrical sensing—is not a flaw, but a sign that the field is technologically vibrant. The next generation of studies will determine which architecture prevails in which clinical setting.
