The LF/HF ratio does not accurately measure cardiac sympatho-vagal balance
George E. Billman
Frontiers in Physiology · 2013
What the research tells us
Billman examines the assumptions needed to interpret LF/HF as cardiac sympathetic–vagal balance. LF is not a purely sympathetic signal, HF is influenced by respiration and mechanical effects, and autonomic branches do not always vary reciprocally or linearly. Similar ratios can therefore arise from different physiological processes.
Scope & interpretation
The critique targets this particular interpretation of LF/HF, not all information carried by HRV. Other measures require assessment of their own physiological basis, breathing, heart rate and recording conditions.
Study at a glance
- POPULATION & SAMPLE
- Existing physiological experiments and mathematical arguments; no new patient cohort.
- EXPOSURE / INTERVENTION / SUBJECT
- Assumptions behind LF, HF and their ratio, drawing on blockade, denervation and respiration studies.
- OUTCOMES
- Mechanisms and assumptions of autonomic interpretation; no new diagnostic-accuracy estimate.
- TIME FRAME
- Different experimental and model time scales; no common follow-up.
Cited on this site
Editorial & review record
Record for v0.3 · Updated
Editorial responsibility: TAP Editorial Team
Editorial note
Under the editorial responsibility of the TAP Editorial Team, this publication used AI assistance for content organization and editing.
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How responsibilities and review are recorded ↗Scope of this reading note
Full-text four assumptions, respiratory/heart-rate influences and conclusion. All cited original experiments have not been individually traced.
- Funding & competing interests
- Funding and competing-interest details have not been verified against the full text. Consult the original publication’s declarations.
Project support
Founded and supported by Resilio.
Revision history
- · v0.3
Added physiological assumptions and the specific scope of the LF/HF critique.