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Altered Excitation-Contraction Coupling in Human Chronic Atrial Fibrillation.

Eleonora Grandi1, Antony J Workman2, Sandeep V Pandit3

  • 1Department of Pharmacology, University of California at Davis, Davis, CA, USA.

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|May 13, 2017
PubMed
Summary

This review examines how chronic atrial fibrillation alters heart cell function, specifically the excitation-contraction coupling process. Understanding these maladaptive changes is key to developing new therapies for atrial fibrillation.

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Area of Science:

  • Cardiology
  • Molecular Biology
  • Physiology

Background:

  • Chronic atrial fibrillation leads to significant cellular remodeling in the atria.
  • This remodeling affects the excitation-contraction coupling process, crucial for heart muscle function.

Purpose of the Study:

  • To review the maladaptive processes in atrial excitation-contraction coupling in chronic atrial fibrillation.
  • To summarize the ionic bases underlying these cellular changes.
  • To highlight the importance of understanding these mechanisms for developing new atrial fibrillation therapies.

Main Methods:

  • Literature review of existing research on atrial fibrillation and excitation-contraction coupling.
  • Analysis of cellular and molecular mechanisms involved in atrial remodeling.
  • Synthesis of current knowledge on ionic bases of altered cardiac function.

Main Results:

  • Atrial remodeling in chronic atrial fibrillation includes shortened action potential duration and effective refractory period.
  • Intracellular calcium transients are depressed, leading to reduced myocyte contractility.
  • Specific ionic changes contribute to these functional alterations.

Conclusions:

  • Understanding the molecular mechanisms of excitation-contraction coupling remodeling is crucial for targeting atrial fibrillation.
  • Identifying the ionic bases of these changes can reveal new therapeutic targets.
  • This knowledge is vital for advancing treatments for patients with chronic atrial fibrillation.