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Updated: Apr 5, 2026

Microelectrode Array Recording of Sinoatrial Node Firing Rate to Identify Intrinsic Cardiac Pacemaking Defects in Mice
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Microelectrode Array Recording of Sinoatrial Node Firing Rate to Identify Intrinsic Cardiac Pacemaking Defects in Mice

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Impaired signaling intrinsic to sinoatrial node pacemaker cells affects heart rate variability during cardiac disease

Yael Yaniv1, Alexey E Lyashkov2, Edward G Lakatta1

  • 1Laboratory of Cardiovascular Science, Biomedical Research Center, Intramural Research Program, National Institute on Aging, NIH, Baltimore, Maryland, USA.

Journal of Clinical Trials
|August 8, 2015
PubMed

Insights

Heart rate variability (HRV) complexity is lost in cardiovascular disease, increasing mortality. This review explores how intrinsic pacemaker cell properties, not just neural control, impact HRV changes in heart diseases.

Area of Science:

  • Cardiology
  • Physiology
  • Computational Biology

Background:

  • Normal heart rhythms exhibit complex, non-stationary patterns.
  • Reduced heart rate variability (HRV) in cardiovascular disease correlates with increased morbidity and mortality.
  • Current understanding of HRV changes in heart disease primarily focuses on autonomic nervous system influences.

Purpose of the Study:

  • To review the mechanisms underlying changes in HRV observed in heart diseases.
  • To highlight the role of intrinsic sinoatrial node pacemaker cell properties in HRV.
  • To explore the impact of impaired autonomic receptor stimulation on these intrinsic properties.

Main Methods:

  • Review of existing literature on heart rate variability and cardiovascular disease.
  • Analysis of the role of coupled-clock mechanisms in sinoatrial node pacemaker cells.
  • Examination of the interaction between intrinsic cell properties and autonomic stimulation.

Main Results:

  • Changes in HRV are not solely due to neural control but also intrinsic pacemaker cell properties.
  • Impaired coupled-clock mechanisms within sinoatrial node cells contribute to altered HRV.
  • Altered responses of these intrinsic properties to autonomic stimulation are implicated in heart disease-related HRV changes.

Conclusions:

  • Intrinsic properties of sinoatrial node pacemaker cells play a crucial role in determining heart rate and HRV.
  • Dysfunctional coupled-clock mechanisms and their response to autonomic stimulation are key factors in HRV alterations in heart disease.
  • Further research into these cellular mechanisms is essential for understanding and managing cardiovascular diseases.

Keywords:
Cardiac denervationCoupled-clock pacemaker systemFractal-like behavior of the heart rate

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