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Thyroid hormones and cardiac arrhythmias

Narcis Tribulova1, Vladimir Knezl, Asher Shainberg

  • 1Institute for Heart Research, Slovak Academy of Sciences, Bratislava, Slovak Republic. narcisa.tribulova@savba.sk

Vascular Pharmacology
|October 24, 2009
PubMed

Insights

Thyroid hormone impacts heart electrical activity and calcium handling. This review explores its dual role in promoting or preventing heart arrhythmias through various mechanisms.

Area of Science:

  • Cardiology
  • Endocrinology
  • Molecular Biology

Background:

  • Thyroid hormone influences cardiac electrophysiology and calcium (Ca2+) handling via genomic and non-genomic pathways.
  • Thyroid dysfunction and systemic diseases cause chronic remodeling of cardiac structure, electrophysiology, and Ca2+ handling.
  • Acute thyroid hormone level changes can alter cardiac cell membrane system activity.

Purpose of the Study:

  • To review the multifaceted effects of thyroid hormone on cardiac function.
  • To elucidate the mechanisms by which thyroid hormone influences cardiac electrophysiology and Ca2+ handling.
  • To discuss the pro- and anti-arrhythmic potential of thyroid hormone in the context of cardiac remodeling and ion channel modulation.

Main Methods:

  • Literature review focusing on thyroid hormone's effects on cardiac ion channels and Ca2+ cycling proteins.
  • Analysis of both genomic and non-genomic mechanisms of thyroid hormone action in the heart.
  • Examination of structural, electrophysiological, and Ca2+ handling remodeling induced by thyroid hormone imbalances.

Main Results:

  • Thyroid hormone exerts significant control over cardiac electrophysiology and intracellular calcium dynamics.
  • Both chronic and acute alterations in thyroid hormone levels lead to cardiac remodeling and functional changes.
  • Modulation of sarcolemmal ion channels, Ca2+ cycling proteins, and intercellular communication by thyroid hormone impacts heart function and arrhythmia susceptibility.

Conclusions:

  • Thyroid hormone critically regulates cardiac electrophysiology and calcium handling, influencing heart function.
  • Thyroid hormone imbalances can lead to cardiac remodeling, affecting susceptibility to arrhythmias.
  • Understanding the pro- and anti-arrhythmic effects of thyroid hormone is crucial for managing cardiac conditions.

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