Quantification of Beat-To-Beat Variability of Action Potential Durations in Langendorff-Perfused Mouse Hearts

  title={Quantification of Beat-To-Beat Variability of Action Potential Durations in Langendorff-Perfused Mouse Hearts},
  author={Gary Tse and Yimei Du and Guoliang Hao and Ka Hou Christien Li and Fiona Yin Wah Chan and Tong Liu and Guangping Li and George Bazoukis and Konstantinos P. Letsas and William K. K. Wu and Shuk Han Cheng and Wing Tak Wong},
  journal={Frontiers in Physiology},
Background: Beat-to-beat variability in action potential duration (APD) is an intrinsic property of cardiac tissue and is altered in pro-arrhythmic states. However, it has never been examined in mice. Methods: Left atrial or ventricular monophasic action potentials (MAPs) were recorded from Langendorff-perfused mouse hearts during regular 8 Hz pacing. Time-domain, frequency-domain and non-linear analyses were used to quantify APD variability. Results: Mean atrial APD (90% repolarization) was 23… 

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