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Isolation of Human Atrial Myocytes for Simultaneous Measurements of Ca2+ Transients and Membrane Currents
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Hysteresis effect implicates calcium cycling as a mechanism of repolarization alternans

Mariah L Walker1, Xiaoping Wan, Glenn E Kirsch

  • 1Heart and Vascular Research Center, MetroHealth Campus, Case Western Reserve University, 2500 MetroHealth Dr, Hamman 330, Cleveland, Ohio 44109-1998, USA.

Circulation
|October 29, 2003
PubMed
Summary

T-wave alternans hysteresis, a phenomenon where alternans persist after heart rate slows, is an intrinsic cardiac myocyte property. This suggests intracellular calcium cycling is key to alternans mechanisms and sudden cardiac death risk.

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