Dynamical mechanism of atrial fibrillation: A topological approach.

  title={Dynamical mechanism of atrial fibrillation: A topological approach.},
  author={Christopher D. Marcotte and Roman O. Grigoriev},
  volume={27 9},
While spiral wave breakup has been implicated in the emergence of atrial fibrillation, its role in maintaining this complex type of cardiac arrhythmia is less clear. We used the Karma model of cardiac excitation to investigate the dynamical mechanisms that sustain atrial fibrillation once it has been established. The results of our numerical study show that spatiotemporally chaotic dynamics in this regime can be described as a dynamical equilibrium between topologically distinct types of… 
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