Assessing Cardiac Dynamics through RF Sensing for Hemodynamic Monitoring in Pacemakers

A. Khaleghi; I. Balasingham; J. Bergsland

arxiv: 2607.00791 · v1 · pith:3IVGFHABnew · submitted 2026-07-01 · 📡 eess.SP · cs.SY· eess.SY

Assessing Cardiac Dynamics through RF Sensing for Hemodynamic Monitoring in Pacemakers

A. Khaleghi , J. Bergsland , I. Balasingham This is my paper

Pith reviewed 2026-07-02 07:36 UTC · model grok-4.3

classification 📡 eess.SP cs.SYeess.SY

keywords RF sensinghemodynamic monitoringpacemakerscardiac dynamicsintracardiac transceiverschamber volumevalve behavior

0 comments

The pith

RF signals between pacemaker leads align with heart rhythm to estimate chamber volumes, valve motion, and pressure shifts.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper tests whether radiofrequency transmissions between leads placed in the right ventricle and right atrium, plus signals reaching a subcutaneous receiver, can serve as a built-in sensor for heart mechanics in pacemaker patients. Measurements show that the strength and timing of these RF variations track the cardiac cycle closely enough to derive estimates of chamber size, when valves open and close, and related pressure changes. A reader would care because the same hardware already implanted for pacing could then supply continuous hemodynamic data without extra sensors or wires. The work frames RF sensing as a practical route to real-time monitoring inside existing pacemaker systems.

Core claim

Temporal RF signal variations between intracardiac transceivers in the right ventricle and right atrium, and between those transceivers and subcutaneous receivers, closely align with cardiac rhythm and thereby permit estimation of chamber volume, valve behavior, and pressure changes.

What carries the argument

RF signal variations between RV-RA intracardiac transceivers and subcutaneous receivers, analyzed for their correlation with the cardiac cycle to extract hemodynamic parameters.

If this is right

RF channels already present in pacemakers can supply real-time estimates of chamber volume, valve behavior, and pressure changes.
This creates a built-in method for hemodynamic monitoring without requiring additional implanted sensors.
Pacemaker systems could use the derived parameters for continuous assessment of cardiac function during normal operation.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

Integration of this sensing could allow pacemakers to adjust pacing rates or modes based on measured volume or pressure trends rather than timing alone.
The same RF links might support detection of acute changes such as fluid overload or valve dysfunction through ongoing signal monitoring.
Future device designs could minimize or eliminate separate hemodynamic sensors by relying on these existing RF pathways.

Load-bearing premise

The RF signal changes are caused mainly by the mechanical motion of the heart chambers and valves rather than by other tissue properties, body motion, or external interference.

What would settle it

If simultaneous recordings show that RF amplitude or phase shifts remain uncorrelated with independent echocardiographic or catheter-based measurements of chamber volume and valve timing across multiple patients and conditions, the claimed alignment would not hold.

read the original abstract

This paper examines the use of radiofrequency (RF) channels for hemodynamic monitoring in cardiac pacemakers. It analyzes RF signal variations between intracardiac transceivers in the right ventricle (RV) and right atrium (RA), as well as subcutaneous receivers, to determine their correlation with cardiac dynamics. The study shows that temporal RF signal variations closely align with cardiac rhythm, allowing for the estimation of parameters such as chamber volume, valve behavior, and pressure changes. These results underscore the potential of RF-based sensing as a novel method for real-time cardiac monitoring in pacemaker systems.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Desk Editor's Note private letter to a colleague

RF sensing for pacemaker hemodynamics is a practical idea but the abstract supplies zero data or validation to back the claim.

read the letter

The main takeaway is that this work proposes using existing RF links inside a pacemaker to track chamber volumes, valves, and pressures from signal variations alone. That is the one thing worth noting.

What the paper actually does is measure time-varying RF between RV and RA transceivers plus a subcutaneous receiver and report that the variations line up with the cardiac cycle. The suggestion is that this alignment lets you estimate hemodynamic parameters without new hardware. The idea itself is straightforward and targets a real need in device-based monitoring.

The execution is thin. No methods section appears, no raw traces or correlation coefficients are shown, and there is no error analysis or comparison to reference measurements like echocardiography or pressure catheters. The central assumption—that cardiac geometry dominates the RF changes over breathing, posture, or tissue conductivity shifts—is stated but not tested in anything visible here. Without those controls the result stays at the level of an observation rather than a demonstrated method.

This is aimed at engineers working on next-generation pacemakers or RF implants. Someone already thinking about in-body propagation might pick up the concept, but the paper does not yet give enough to build on or cite for a specific result.

If the full manuscript contains controlled experiments, quantitative accuracy figures, and a clear handling of confounders, it would be worth sending out for review. On the basis of the abstract alone it does not reach that threshold.

Referee Report

2 major / 0 minor

Summary. The manuscript examines the use of radiofrequency (RF) channels for hemodynamic monitoring in cardiac pacemakers. It analyzes temporal RF signal variations between intracardiac transceivers in the right ventricle (RV) and right atrium (RA), as well as subcutaneous receivers, and reports that these variations closely align with cardiac rhythm, thereby enabling estimation of parameters such as chamber volume, valve behavior, and pressure changes.

Significance. If the empirical alignment and estimation accuracy hold under rigorous validation, the work could enable integrated real-time hemodynamic sensing within existing pacemaker hardware without additional sensors. This would be a meaningful contribution to signal-processing applications in implantable devices, provided the RF variations are shown to be dominantly driven by cardiac geometry rather than confounders.

major comments (2)

[Abstract] Abstract: the central claim that RF variations 'allow for the estimation' of chamber volume, valve behavior, and pressure changes is presented without any quantitative correlation coefficients, error metrics, sample size, or comparison to reference measurements (e.g., echocardiography or pressure catheters). This absence makes it impossible to assess whether the alignment is sufficient for the claimed parameter estimation.
[Abstract] The weakest assumption—that observed RF variations are primarily and sufficiently driven by cardiac hemodynamics—requires explicit testing against motion artifacts, respiration, and tissue dielectric changes; no such controls or sensitivity analysis are described.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the detailed and constructive review. The comments highlight important areas for improving clarity and rigor in the abstract and supporting claims. We address each point below and will incorporate revisions to strengthen the manuscript.

read point-by-point responses

Referee: [Abstract] Abstract: the central claim that RF variations 'allow for the estimation' of chamber volume, valve behavior, and pressure changes is presented without any quantitative correlation coefficients, error metrics, sample size, or comparison to reference measurements (e.g., echocardiography or pressure catheters). This absence makes it impossible to assess whether the alignment is sufficient for the claimed parameter estimation.

Authors: We agree that the abstract would benefit from quantitative support. The full manuscript presents alignment results through temporal signal analysis and figures showing correspondence with cardiac cycles, but the abstract itself is qualitative. We will revise the abstract to incorporate key metrics from the study (e.g., correlation values, error measures, and sample details) to allow readers to evaluate the estimation claims directly. revision: yes
Referee: [Abstract] The weakest assumption—that observed RF variations are primarily and sufficiently driven by cardiac hemodynamics—requires explicit testing against motion artifacts, respiration, and tissue dielectric changes; no such controls or sensitivity analysis are described.

Authors: This comment correctly identifies a gap. The presented work focuses on observed correlations with cardiac rhythm without dedicated experiments isolating against the listed confounders. We will revise the manuscript to add an explicit discussion of these potential confounders, including any preliminary observations from the data and a clear statement of limitations, with plans for future controlled validation. revision: partial

Circularity Check

0 steps flagged

No significant circularity; empirical observation only

full rationale

The paper presents an empirical study of RF signal variations in cardiac tissue, reporting observed correlations between temporal RF changes and cardiac rhythm without any derivation chain, equations, fitted parameters, or self-citations that reduce a claimed result to its own inputs. The abstract and described content frame the alignment as a measured outcome from experiments rather than a constructed prediction or self-defined quantity. No load-bearing steps exist that match the enumerated circularity patterns, so the analysis is self-contained against external benchmarks.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 0 invented entities

Abstract-only review; no explicit parameters, axioms, or entities detailed. Assumes standard RF propagation in biological tissue as background.

axioms (1)

domain assumption RF signal variations are dominantly caused by cardiac tissue and chamber changes
Invoked to link signal changes to volume, valves, and pressure.

pith-pipeline@v0.9.1-grok · 5627 in / 1131 out tokens · 21897 ms · 2026-07-02T07:36:12.240272+00:00 · methodology

discussion (0)

Reference graph

Works this paper leans on

5 extracted references · 5 canonical work pages

[1]

Cardiac Pacemakers: Function, Troubleshooting, and Management: Part 1 of a 2 -Part Series,

S. K. Mulpuru, M. Madhavan, C. J. McLeod, Y. M. Cha, and P. A. Friedman, “Cardiac Pacemakers: Function, Troubleshooting, and Management: Part 1 of a 2 -Part Series,” J. Am. Coll. Cardiol. , vol. 69, no. 2, pp. 189–210, Jan. 2017, doi: 10.1016/J.JACC.2016.10.061

work page doi:10.1016/j.jacc.2016.10.061 2017
[2]

Leadless pacemakers: a contemporary review,

N. Bhatia and M. El -Chami, “Leadless pacemakers: a contemporary review,” J. Geriatr. Cardiol. , vol. 15, no. 4, p. 249, 2018, doi: 10.11909/J.ISSN.1671-5411.2018.04.002

work page doi:10.11909/j.issn.1671-5411.2018.04.002 2018
[3]

Randomized Controlled Trial of an Implantable Continuous Hemodynamic Monitor in Patients With Advanced Heart Failure: The COMPASS-HF Study,

R. C. Bourge et al., “Randomized Controlled Trial of an Implantable Continuous Hemodynamic Monitor in Patients With Advanced Heart Failure: The COMPASS-HF Study,” J. Am. Coll. Cardiol., vol. 51, no. 11, pp. 1073–1079, Mar. 2008, doi: 10.1016/J.JACC.2007.10.061

work page doi:10.1016/j.jacc.2007.10.061 2008
[4]

Safety, usability, and performance of a wireless left atrial pressure monitoring system in patients with heart failure: the VECTOR-HF trial,

D. D’Amario et al., “Safety, usability, and performance of a wireless left atrial pressure monitoring system in patients with heart failure: the VECTOR-HF trial,” Eur. J. Heart Fail. , vol. 25, no. 6, pp. 902 –911, 2023, doi: 10.1002/ejhf.2869

work page doi:10.1002/ejhf.2869 2023
[5]

Safety and efficacy of a wireless pulmonary artery pressure sensor: primary endpoint results of the SIRONA 2 clinical trial,

F. Sharif et al. , “Safety and efficacy of a wireless pulmonary artery pressure sensor: primary endpoint results of the SIRONA 2 clinical trial,” ESC Hear. Fail. , vol. 9, no. 5, pp. 2862 –2872, 2022, doi: 10.1002/ehf2.14006

work page doi:10.1002/ehf2.14006 2022

[1] [1]

Cardiac Pacemakers: Function, Troubleshooting, and Management: Part 1 of a 2 -Part Series,

S. K. Mulpuru, M. Madhavan, C. J. McLeod, Y. M. Cha, and P. A. Friedman, “Cardiac Pacemakers: Function, Troubleshooting, and Management: Part 1 of a 2 -Part Series,” J. Am. Coll. Cardiol. , vol. 69, no. 2, pp. 189–210, Jan. 2017, doi: 10.1016/J.JACC.2016.10.061

work page doi:10.1016/j.jacc.2016.10.061 2017

[2] [2]

Leadless pacemakers: a contemporary review,

N. Bhatia and M. El -Chami, “Leadless pacemakers: a contemporary review,” J. Geriatr. Cardiol. , vol. 15, no. 4, p. 249, 2018, doi: 10.11909/J.ISSN.1671-5411.2018.04.002

work page doi:10.11909/j.issn.1671-5411.2018.04.002 2018

[3] [3]

Randomized Controlled Trial of an Implantable Continuous Hemodynamic Monitor in Patients With Advanced Heart Failure: The COMPASS-HF Study,

R. C. Bourge et al., “Randomized Controlled Trial of an Implantable Continuous Hemodynamic Monitor in Patients With Advanced Heart Failure: The COMPASS-HF Study,” J. Am. Coll. Cardiol., vol. 51, no. 11, pp. 1073–1079, Mar. 2008, doi: 10.1016/J.JACC.2007.10.061

work page doi:10.1016/j.jacc.2007.10.061 2008

[4] [4]

Safety, usability, and performance of a wireless left atrial pressure monitoring system in patients with heart failure: the VECTOR-HF trial,

D. D’Amario et al., “Safety, usability, and performance of a wireless left atrial pressure monitoring system in patients with heart failure: the VECTOR-HF trial,” Eur. J. Heart Fail. , vol. 25, no. 6, pp. 902 –911, 2023, doi: 10.1002/ejhf.2869

work page doi:10.1002/ejhf.2869 2023

[5] [5]

Safety and efficacy of a wireless pulmonary artery pressure sensor: primary endpoint results of the SIRONA 2 clinical trial,

F. Sharif et al. , “Safety and efficacy of a wireless pulmonary artery pressure sensor: primary endpoint results of the SIRONA 2 clinical trial,” ESC Hear. Fail. , vol. 9, no. 5, pp. 2862 –2872, 2022, doi: 10.1002/ehf2.14006

work page doi:10.1002/ehf2.14006 2022