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Cited by 51Cardiac pacing and defibrillation studiesWireless Power Transfer SystemsWireless Body Area Networks

Synchronized Biventricular Heart Pacing in a Closed-chest Porcine Model based on Wirelessly Powered Leadless Pacemakers

Open access
Lyu, Hongming, John, Mathews, Burkland, David, Greet, Brian, Post, Allison, Babakhani, Aydin, Razavi, Mehdi·2020·Scientific Reports
DOI 10.1038/s41598-020-59017-zPMC PMC7005712
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Abstract

About 30% of patients with impaired cardiac function have ventricular dyssynchrony and seek cardiac resynchronization therapy (CRT). In this study, we demonstrate synchronized biventricular (BiV) pacing in a leadless fashion by implementing miniaturized and wirelessly powered pacemakers. With their flexible form factors, two pacemakers were implanted epicardially on the right and left ventricles of a porcine model and were inductively powered at 13.56 MHz and 40.68 MHz industrial, scientific, and medical (ISM) bands, respectively. The power consumption of these pacemakers is reduced to µW-level by a novel integrated circuit design, which considerably extends the maximum operating distance. Leadless BiV pacing is demonstrated for the first time in both open-chest and closed-chest porcine settings. The clinical outcomes associated with different interventricular delays are verified through electrophysiologic and hemodynamic responses. The closed-chest pacing only requires the external source power of 0.3 W and 0.8 W at 13.56 MHz and 40.68 MHz, respectively, which leads to specific absorption rates (SARs) 2-3 orders of magnitude lower than the safety regulation limit. This work serves as a basis for future wirelessly powered leadless pacemakers that address various cardiac resynchronization challenges.

Integrity signals

Registry

Crossref · 10.1038/s41598-020-59017-z

Cites

42 of 42 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

9 of 24 cited sources checked · 6 supported · 1 flagged · accuracy not yet measured

  • Findingown data

    The proposed inductive coupling links at 13.56 MHz and 40.68 MHz produce SARs 2-3 orders of magnitude below the safety threshold.

    “It is remarkable that unlike prior arts operating at hundreds of MHz4,6,7, the proposed inductive coupling links at 13.56 MHz and 40.68 MHz bands render SARs 2–3 orders of magnitude lower than the safety regulation threshold.”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites [4] Ho, J. S. et al. Wireless power transfer to deep-tissue microimplants. Proceedings of the National Academy of Sciences 111, 7974–7979 (2014). source

      The Electromagnetic Region of Operation section identifies this paper’s operating frequency as 1.6 GHz, not 13.56 or 40.68 MHz. The Results report maximum 10-g SARs of 0.89 W/kg and 1.17 W/kg against a 10 W/kg threshold—roughly one order of magnitude lower, not two to three. The cited paper describes a different, higher-frequency system rather than the proposed links. (LLM, conf=0.91)

      Checked by a reasoning model — may be wrong.

      Experimental — accuracy not yet measured
    • cites [6] Lyu, H., Wang, J., La, J.-H., Chung, J. M. & Babakhani, A. An energy-efficient wirelessly powered millimeter-scale neurostimulator implant based on systematic codesign of an inductive loop antenna and a custom rectifier. IEEE transactions on biomedical circuits and systems 12, 1131–1143 (2018). source
    • cites [7] Lyu, H., Gad, P., Zhong, H., Edgerton, V. R. & Babakhani, A. A 430-MHz wirelessly powered implantable pulse generator with intensity/rate control and sub-1 μA quiescent current consumption. IEEE transactions on biomedical circuits and systems 13, 180–190 (2019). source
    • Rests on an assumption: The SAR simulation using a male torso model is representative of human safety.
  • Premisecitation

    Earlier studies have tested wirelessly powered single-site cardiac pacing in rodent, rabbit, and open-chest porcine models.

    “Prior studies have investigated wirelessly powered single-site cardiac pacing on rodent, rabbit and open-chest porcine models4,5,21.”
    Quote in the paperSubstantial claim2 of 3 sources checked
    • cites [4] Ho, J. S. et al. Wireless power transfer to deep-tissue microimplants. Proceedings of the National Academy of Sciences 111, 7974–7979 (2014). source
    • cites [5] Abiri, P. et al. Inductively powered wireless pacing via a miniature pacemaker and remote stimulation control system. Scientific Reports 7 (2017). source
    • cites [21] Lyu, H. et al. Leadless multisite pacing: A feasibility study using wireless power transfer based on Langendorff rodent heart models. Journal of cardiovascular electrophysiology 29, 1588–1593 (2018). source
  • Findingnone given

    Two inductively powered leadless pacemakers were built to operate at 13.56 and 40.68 MHz ISM bands.

    “In this work, we implement two inductively powered leadless pacemakers operating at 13.56 MHz and 40.68 MHz industrial, scientific, and medical (ISM) bands, respectively.”
    Quote in the paperSubstantial claim
  • Findingnone given

    This work is the first to synchronize multiple leadless pacemakers in a closed-chest porcine model.

    “This work takes a stride further to demonstrate the synchronization of multiple leadless pacemakers for the first time in a closed-chest porcine model.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The porcine model is representative of human cardiac resynchronization physiology and clinical outcomes.
  • Findingnone given

    Closed-chest BiV pacing was demonstrated with SARs orders of magnitude below the safety limit.

    “Closed-chest BiV pacing was further demonstrated with the specific absorption rate (SAR) orders of magnitude lower than the safety regulation limit.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The SAR simulation using a male torso model is representative of human safety.
  • May combine two claims. 22
  • Classified as probably not a substantial claim. 6

  • May combine two claims.

    Premisecitation

    Transvenous leads are linked to complications including lead dislodgement, tricuspid valve dysfunction, and thromboembolism.

    “Transvenous leads are also associated with various complications such as lead dislodgement15, tricuspid valve dysfunction16, and thromboembolism17, etc., which would be solved with leadless pacemaker technologies18–20.”
    Quote in the paperSubstantial claim2 of 3 sources checked
    • cites [15] Udo, E. O. et al. Incidence and predictors of short-and long-term complications in pacemaker therapy: the FOLLOWPACE study. 9, 728–735 (2012). source
    • cites [16] Chang, J. D., Manning, W. J., Ebrille, E. & Zimetbaum, P. J. Tricuspid valve dysfunction following pacemaker or cardioverter-defibrillator implantation. 69, 2331–2341 (2017). source
    • cites [17] Buttigieg, J., Asciak, R. & Azzopardi, C. M. Pacemaker lead-associated thrombosis in cardiac resynchronisation therapy. 2015, bcr2015210314 (2015). source

  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation

    Wireless power transfer techniques can shrink the form factor and reduce invasiveness of implantable medical devices.

    “While many remain battery-powered, wireless power transfer techniques can further reduce the form factor and invasiveness of these devices4–10.”
    Quote in the paperSubstantial claim3 of 7 sources checked
    • cites [4] Ho, J. S. et al. Wireless power transfer to deep-tissue microimplants. Proceedings of the National Academy of Sciences 111, 7974–7979 (2014). source
      Experimental — accuracy not yet measured
    • cites [5] Abiri, P. et al. Inductively powered wireless pacing via a miniature pacemaker and remote stimulation control system. Scientific Reports 7 (2017). source
      Experimental — accuracy not yet measured
    • cites [6] Lyu, H., Wang, J., La, J.-H., Chung, J. M. & Babakhani, A. An energy-efficient wirelessly powered millimeter-scale neurostimulator implant based on systematic codesign of an inductive loop antenna and a custom rectifier. IEEE transactions on biomedical circuits and systems 12, 1131–1143 (2018). source
    • cites [7] Lyu, H., Gad, P., Zhong, H., Edgerton, V. R. & Babakhani, A. A 430-MHz wirelessly powered implantable pulse generator with intensity/rate control and sub-1 μA quiescent current consumption. IEEE transactions on biomedical circuits and systems 13, 180–190 (2019). source
    • cites [8] Agarwal, A. et al. A 4μW, ADPLL-based implantable amperometric biosensor in 65nm CMOS. Symposium on VLSI Circuits. C108-C109 (2017). source
    • cites [9] Liao, Y.-T., Yao, H., Lingley, A., Parviz, B. & Otis, B. P. A 3-µW CMOS Glucose Sensor for Wireless Contact-Lens Tear Glucose Monitoring. IEEE Journal of Solid-State Circuits 47, 335–344 (2011). source
    • cites [10] Mickle, A. D. et al. A wireless closed-loop system for optogenetic peripheral neuromodulation. Nature 565, 361 (2019). source

      The device description reports a miniaturized implant with wireless power transfer, and Methods > Wireless communication describes a battery-free version. The device description also says its design avoids direct nerve interfaces and bladder incisions. Neither passage establishes that wireless power transfer itself reduces implant size or invasiveness relative to battery-powered devices. (LLM, conf=0.78)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    The WiSE CRT system requires a standard dual-chamber pacemaker with only the LV wirelessly paced by ultrasound, which limits the benefits of leadless pacing.

    “The current embodiment of this technology requires the use of a standard dual-chamber pacemaker with only the LV wirelessly paced via ultrasound power transfer, thus limiting the potential benefits of leadless pacing.”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [34] Sieniewicz, B. J. et al. Guidance for optimal site selection of a leadless left ventricular endocardial electrode improves acute hemodynamic response and chronic remodeling. JACC: Clinical Electrophysiology 4, 860–868 (2018).

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites [35] Leo, M., Webster, D. & Betts, T. R. Acute electrical and hemodynamic effects of endocardial biventricular pacing using the Wi SE CRT system and conventional epicardial biventricular pacing. Journal of arrhythmia 34, 87–89 (2018). source

      The Case Report (page unavailable) describes wireless ultrasound-powered LV stimulation used alongside a preimplanted RV pacing device, supporting the claim that only the LV was wirelessly paced in this case. It does not say that WiSE CRT requires a standard dual-chamber pacemaker or state that this arrangement limits the benefits of leadless pacing. (LLM, conf=0.85)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Findingnone given

    The pacemaker has μW-level power consumption from a custom low-power IC and is built on a flexible polyimide substrate measuring 11 mm × 11 mm.

    “The pacemaker features a µW-level power consumption enabled by a custom low-power IC and is implemented on a flexible polyimide substrate with a dimension of 11 mm × 11 mm.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingnone given

    Two such pacemakers were implanted epicardially on the RV and LV of a porcine model for synchronized BiV pacing with adjustable interventricular offsets.

    “To demonstrate wireless CRT, two such pacemakers were epicardially implanted on the right ventricle (RV) and left ventricle (LV) in a porcine model for synchronized biventricular (BiV) pacing with controllable interventricular offsets.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    This work is the first demonstration of multisite CRT using batteryless and leadless pacemakers, with improved interventricular synchronization and cardiac stroke volumes.

    “This work is the first demonstration of the multisite CRT based on batteryless and leadless pacemakers with improved clinical outcomes in both interventricular synchronization and cardiac stroke volumes.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The porcine model is representative of human cardiac resynchronization physiology and clinical outcomes.
    • Rests on an assumption: Acute electrophysiologic and hemodynamic improvements in the porcine model predict chronic clinical benefit in humans.

  • May combine two claims.

    Findingown data

    Closed-chest RV pacing and LV pacing were enabled with transmit power as low as 25 dBm (0.3 W) and 29 dBm (0.8 W), respectively.

    “Closed-chest RV pacing and LV pacing were enabled with Tx power as low as 25 dBm (0.3 W) and 29 dBm (0.8 W), respectively.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    The fabricated pacemaker measures 11 mm × 11 mm and sits on a 25 μm thick flexible polyimide substrate that houses traces and the inductive coil.

    “The device features an 11 mm × 11 mm dimension and resides on a 25 µm thick flexible polyimide substrate housing the traces and the inductive coil.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingnone given

    The wirelessly powered pacemakers have μW-level power consumption and a miniaturized flexible form factor suitable for epicardial implantation.

    “In summary, we report wirelessly powered pacemakers which feature µW-level power consumption and a miniaturized and flexible form factor that is suitable for epicardial implantation.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    The 13.56 MHz and 40.68 MHz links generate maximum SARs of approximately 0.04 W/kg and 0.3 W/kg, respectively.

    “The two links generate the maximum SARs of approximately 0.04 W/kg and 0.3 W/kg, respectively, as shown in Fig. 6i,j, which are significantly lower than the 10 W/kg limit according to IEEE Std C95.1–2005.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The SAR simulation using a male torso model is representative of human safety.

  • May combine two claims.

    Findingown data

    The 13.56 MHz and 40.68 MHz links required transmit power of 0.3 W and 0.8 W, respectively, leading to SARs 2-3 orders of magnitude below the safety threshold.

    “The 13.56 MHz and 40.68 MHz links only required the Tx power of 0.3 W and 0.8 W, respectively, which lead to SARs 2–3 orders of magnitude below the safety threshold.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The SAR simulation using a male torso model is representative of human safety.

  • May combine two claims.

    Findingown data

    BiV pacing with RV leading by 40 ms worsens the result, suggesting conflict with inherent conduction.

    “In contrast, BiV pacing with RV leading by 40 ms shows a worsened result, suggesting a contradiction to the inherent conduction.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    RV pacing gives a QRS morphology with an initially positive vector, whereas LV pacing gives a negative initial vector.

    “RV pacing results in a QRS morphology with an initially positive vector, while LV pacing features a negative initial vector.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingreasoning

    Each pacemaker weighs about 90 mg because it has no battery.

    “The weight of each pacemaker is only about 90 mg due to the elimination of batteries.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingnone given

    This work demonstrates synchronized leadless pacing over multiple sites for the first time, and the approach may offer more flexibility and advantages in customizing CRTs for different individuals.

    “The proposed work demonstrates synchronized leadless pacing over multiple sites for the first time, and this approach can potentially offer more flexibility and advantages in customizing CRTs for different individuals.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The porcine model is representative of human cardiac resynchronization physiology and clinical outcomes.

  • May combine two claims.

    Findingown data

    They were implanted on the RV and LV of a porcine model, successfully demonstrating leadless CRT.

    “They were implanted on the RV and LV of a porcine model, respectively, which successfully demonstrated the leadless CRT.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The porcine model is representative of human cardiac resynchronization physiology and clinical outcomes.

  • May combine two claims.

    Findingown data

    The intrinsic non-pathologic heartbeat has a QRS duration of 60 ms, and BiV pacing with zero offset gives a similar value.

    “The QRS duration of the intrinsic non-pathologic heartbeat is 60 ms and BiV pacing with zero offset renders a similar value.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    BiV pacing with zero offset gives a VTI close to the inherent value, consistent with the QRS duration result.

    “In contrast, BiV pacing with zero offset leads to a VTI close to the inherent value (Fig. 5d), which is consistent with the QRS duration result.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    With 1 W transmit power, the 40.68 MHz and 13.56 MHz links achieve maximum operating distances of 8.5 cm and 11 cm, respectively.

    “With 1 W Tx power, 40.68 MHz and 13.56 MHz links render the maximum operating distance of 8.5 cm and 11 cm as shown in Fig. 3f,g, respectively.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Different pacing modalities were studied, and BiV pacing improved QRS duration and cardiac stroke volumes.

    “Different pacing modalities, i.e., single-site pacing and BiV pacing with different offsets, were studied, and BiV pacing showed improvements in the QRS duration and cardiac stroke volumes.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The porcine model is representative of human cardiac resynchronization physiology and clinical outcomes.
    • Rests on an assumption: Acute electrophysiologic and hemodynamic improvements in the porcine model predict chronic clinical benefit in humans.

  • May combine two claims.

    Findingown data

    Two pacemakers were implemented at 13.56 MHz and 40.68 MHz, achieving maximum operating distances of 11 cm and 8.5 cm from 1 W transmit coils.

    “Two pacemakers were implemented at 13.56 MHz and 40.68 MHz ISM bands, demonstrating the maximum operating distance of 11 cm and 8.5 cm from 1 W Tx coils, respectively.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Reported six-month nonresponder rates reach 32-43%, partly due to anatomic limits on lead positioning.

    “While clinical improvements are generally achieved, six-month nonresponder rates have been reported to be as high as 32–43%11,13, which is partially attributed to anatomic constraints of lead positioning14.”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites [11] Abraham, W. T. et al. Cardiac resynchronization in chronic heart failure. New England Journal of Medicine 346, 1845–1853 (2002). source
    • cites [13] Bristow, M. R. et al. Cardiac-resynchronization therapy with or without an implantable defibrillator in advanced chronic heart failure. The New England journal of medicine 2004, 2140–2150 (2004). source
    • cites [14] Daubert, J.-C. et al. 2012 EHRA/HRS expert consensus statement on cardiac resynchronization therapy in heart failure: implant and follow-up recommendations and management. Heart rhythm 9, 1524–1576 (2012). source

  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing), S4 (based).

    Interpretationnone given

    The wireless powering approach can be applied to other medical implants.

    “The wireless powering strategy can be applied to various other medical implants as well.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    About 30% of individuals with compromised heart function exhibit ventricular dyssynchrony and require CRT.

    “About 30% of patients with impaired cardiac function have ventricular dyssynchrony and seek cardiac resynchronization therapy (CRT).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [11] Abraham, W. T. et al. Cardiac resynchronization in chronic heart failure. New England Journal of Medicine 346, 1845–1853 (2002). source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    All experiments and methods followed protocols approved by the IACUC of Texas Heart Institute.

    “All experiments and methods were performed in accordance with the protocols approved by the Institutional Animal Care and Use Committee (IACUC) of Texas Heart Institute.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationreasoning

    Our technology does not have those limitations.

    “Our technology, however, does not have such limitations.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationown data

    The proposed batteryless and leadless pacing platform shows promise for advanced therapies in cardiac synchronization.

    “The proposed batteryless and leadless pacing platform shows promise in providing advanced therapies in cardiac synchronization.”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: The porcine model is representative of human cardiac resynchronization physiology and clinical outcomes.
    • Rests on an assumption: Acute electrophysiologic and hemodynamic improvements in the porcine model predict chronic clinical benefit in humans.
27 of 27

  • The paper relies on this without support.

    The porcine model is representative of human cardiac resynchronization physiology and clinical outcomes.

    “The clinical outcomes associated with different interventricular delays are verified through electrophysiologic and hemodynamic responses.”

  • The paper relies on this without support.

    Acute electrophysiologic and hemodynamic improvements in the porcine model predict chronic clinical benefit in humans.

    “The improved clinical outcome is verified through both electrophysiologic and hemodynamic studies.”

  • The paper relies on this without support.

    The SAR simulation using a male torso model is representative of human safety.

    “The SARs associated with the 13.56 MHz and 40.68 MHz links are investigated with the Tx coils positioned at 1 cm proximity to a male torso model.”
3 of 3

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • One SAR is less than two orders of magnitude below the limit

    Minor

    The reported 0.3 W/kg SAR is about 33 times below the stated 10 W/kg limit, or roughly 1.5 orders of magnitude-not the claimed 2-3 orders.

1 of 1

Cites

Flagged first, then by citations

5 of the 47 references couldn’t be matched to a known paper.

Cited by

Sorted by citations

Related

Authors
Lyu, H., John, M., Burkland, D., Greet, B., Post, A., Babakhani, A., & Razavi, M.
Affiliations
  • University of California, Los Angeles (US)
  • Baylor College of Medicine (US)
Corresponding author
  • Babakhani, Aydin
  • Razavi, Mehdi
ORCID
Venue
Scientific Reports
Publisher
Springer Science and Business Media LLC
Published
2020-02-07
Volume
10
Issue
1
Pages
2067-2067
ISSN
2045-2322 (ISSN-L)
DOI
10.1038/s41598-020-59017-z
PMC
PMC7005712
OpenAlex
W3005502734
Cited by
51
References
47
Citations by year
2026: 3 · 2025: 12 · 2024: 11 · 2023: 6 · 2022: 9 · 2021: 8 · 2020: 2
FWCI
3.87
Type
journal article
Language
en
Update notices
correction (2020-04-07)
Open access
Licence
Locations
  • Scientific Reports (publishedVersion, cc-by)
  • Europe PMC (PubMed Central) (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion)
  • eScholarship (California Digital Library) (submittedVersion)
  • eScholarship (California Digital Library) (submittedVersion, cc-by)
Topics
  • Health Sciences › Medicine › Cardiology and Cardiovascular Medicine › Cardiac pacing and defibrillation studies
  • Physical Sciences › Engineering › Electrical and Electronic Engineering › Wireless Power Transfer Systems
  • Physical Sciences › Engineering › Biomedical Engineering › Wireless Body Area Networks
Keywords
cardiac resynchronization therapy, leadless pacemaker, wireless power transfer, inductive power transfer, ventricular dyssynchrony, porcine model, ISM band, power consumption, specific absorption rate, interventricular delay, hemodynamics
MeSH terms
Animals, Disease Models, Animal, Electrocardiography, Equipment Design, Female, Electric Power Supplies, Swine, Defibrillators, Implantable, Cardiac Resynchronization Therapy Devices, Wireless Technology

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read under definition version 3 (extract-v3) on 2026-09-28.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-09-28.

Cited sources are checked by gpt-6-sol.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

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