Arrhythmogenic Mechanisms in Heart Failure: Linking β-Adrenergic Stimulation, Stretch, and Calcium

Daniel M Johnson1, Gudrun Antoons2

  • 1Department of Cardiothoracic Surgery, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, Netherlands.

Frontiers in Physiology
|October 31, 2018
PubMed

Insights

This review explores how beta-adrenergic stimulation and mechanical load in heart failure (HF) disrupt calcium handling in heart cells. These disruptions increase the risk of arrhythmias, offering targets for new HF therapies.

Area of Science:

  • Cardiology
  • Molecular Biology
  • Electrophysiology

Background:

  • Heart failure (HF) involves increased sympathetic tone and mechanical load, contributing to cardiac dysfunction.
  • These factors can lead to electrical instability in the heart, particularly through altered calcium (Ca2+) handling in cardiac myocytes.
  • This review focuses on the interplay between these elements and their role in heart failure-associated arrhythmias.

Purpose of the Study:

  • To provide a comprehensive overview of the connections between beta-adrenergic stimulation, mechanical load, and arrhythmogenesis in heart failure.
  • To elucidate the mechanisms by which Ca2+ handling alterations contribute to electrical instability in HF.
  • To identify common pathways for potential therapeutic interventions.

Main Methods:

  • Review of existing literature on beta-adrenergic signaling, mechanical stress, and cardiac arrhythmias in heart failure.
  • Analysis of the role of Ca2+ handling, afterdepolarizations, and ion channel function.
  • Discussion of cellular remodeling and microdomain alterations in HF.

Main Results:

  • Beta-adrenergic stimulation and mechanical load can induce afterdepolarizations, increasing arrhythmia risk.
  • Alterations in Ca2+ handling, including ryanodine receptor sensitivity and stretch-activated channels, are implicated in HF-related arrhythmias.
  • Remodeling in HF exacerbates these arrhythmogenic triggers.

Conclusions:

  • The cross-talk between beta-adrenergic signaling, mechanical load, and Ca2+ dysregulation is a key driver of arrhythmias in heart failure.
  • Understanding these mechanisms can guide the development of novel therapeutic strategies targeting common pathways.
  • Interventions aimed at modulating Ca2+ handling or downstream signaling may mitigate HF-associated electrical instability.

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