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Calcium alternans in cardiac myocytes: order from disorder

Zhilin Qu1, Michael Nivala, James N Weiss

  • 1Department of Medicine (Cardiology), David Geffen School of Medicine, University of California, Los Angeles, CA, USA. zqu@mednet.ucla.edu

Journal of Molecular and Cellular Cardiology
|October 30, 2012
PubMed

Insights

Calcium alternans, linked to increased heart disease mortality, is explained by a new

Area of Science:

  • Cardiology
  • Biophysics
  • Computational Biology

Background:

  • Calcium alternans is a significant predictor of mortality in heart disease.
  • It is associated with T-wave alternans and pulsus alternans.
  • Understanding its mechanisms is crucial for improving patient outcomes.

Purpose of the Study:

  • To present a holistic theoretical framework for understanding calcium alternans.
  • To link the effects of calcium cycling proteins to key properties of cardiac calcium cycling.
  • To reconcile contradictory experimental findings on calcium alternans.

Main Methods:

  • Review of recent experimental, computational, and theoretical studies.
  • Development of a theoretical framework ('3R theory').
  • Analysis of cardiac calcium cycling network properties: randomness, refractoriness, and recruitment.

Main Results:

  • Disordered subcellular stochastic processes can organize into ordered periodic behaviors.
  • The '3R theory' provides a unified explanation for calcium alternans.
  • The theory links protein function to network properties (randomness, refractoriness, recruitment).

Conclusions:

  • The '3R theory' offers a novel perspective on calcium alternans.
  • This framework helps explain complex calcium cycling dynamics in the heart.
  • It has the potential to reconcile diverse experimental observations in the field.

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