Electrophysiological mechanisms of ventricular arrhythmias in relation to Andersen-Tawil syndrome under conditions of reduced IK1: a simulation study.

@article{Sung2006ElectrophysiologicalMO,
  title={Electrophysiological mechanisms of ventricular arrhythmias in relation to Andersen-Tawil syndrome under conditions of reduced IK1: a simulation study.},
  author={R. Sung and Sheng-Nan Wu and Jiun-Shian Wu and Han-Dong Chang and C. Luo},
  journal={American journal of physiology. Heart and circulatory physiology},
  year={2006},
  volume={291 6},
  pages={
          H2597-605
        }
}
  • R. Sung, Sheng-Nan Wu, +2 authors C. Luo
  • Published 2006
  • Medicine
  • American journal of physiology. Heart and circulatory physiology
Patients with Andersen-Tawil syndrome (ATS) mostly have mutations on the KCNJ2 gene, producing loss of function or dominant-negative suppression of the inward rectifier K(+) channel Kir2.1. However, clinical manifestations of ATS including dysmorphic features, periodic paralysis (hypo-, hyper-, or normokalemic), long QT, and ventricular arrhythmias (VAs) are considerably variable. Using a modified dynamic Luo-Rudy simulation model of cardiac ventricular myocytes, we attempted to elucidate… Expand
Mechanism of U wave and polymorphic ventricular tachycardia in a canine tissue model of Andersen-Tawil syndrome.
TLDR
CsCl blockade of I(K1) produced a ventricular wedge model of ATS, which generated U waves by delaying late repolarization of APs and creating D ADs, and promoted polymorphic VT by triggering DADs at multiple shifting sites. Expand
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
Each short QT variant uniquely increased the transmural dispersion of action potential duration across the ventricular wall, increased the temporal window of tissue vulnerability to premature excitation stimulus, leading to increased susceptibility to re-entrant arrhythmia. Expand
Andersen-Tawil syndrome: clinical and molecular aspects.
TLDR
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TLDR
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