Electrophysiological Mechanism of Enhanced Susceptibility of Hypertrophied Heart to Acquired Torsade de Pointes Arrhythmias: Tridimensional Mapping of Activation and Recovery Patterns

@article{Kozhevnikov2002ElectrophysiologicalMO,
  title={Electrophysiological Mechanism of Enhanced Susceptibility of Hypertrophied Heart to Acquired Torsade de Pointes Arrhythmias: Tridimensional Mapping of Activation and Recovery Patterns},
  author={Dmitry O Kozhevnikov and Keiji Yamamoto and Dionyssios A. Robotis and Mark Restivo and Nabil El-Sherif},
  journal={Circulation: Journal of the American Heart Association},
  year={2002},
  volume={105},
  pages={1128-1134}
}
Background—Cardiac hypertrophy is associated with increased incidence of sudden death and susceptibility to proarrhythmic effects of antiarrhythmic agents. However, the in vivo electrophysiologic mechanism of the arrhythmias has not been investigated in detail. Methods and Results—Dose-dependent susceptibility to Torsade de Pointes (TdP) by class III drug dofetilide, 3, 10, and 30 &mgr;g/kg, was compared in 6 control dogs (C) and in 5 dogs 6 to 8 weeks after induction of complete… Expand
Severe Bradycardia Increases the Incidence and Severity of Torsade de Pointes Arrhythmias by Augmenting Preexistent Spatial Dispersion of Repolarization in the CAVB Dog Model
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In CAVB dogs, severe bradycardia increases the probability and severity of arrhythmic events by heterogeneously causing electrophysiological instability, which is mainly reflected in an increased spatial, and to a lesser extent temporal, dispersion of repolarization. Expand
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