K+ Channel Isoforms Regulate Human Atrial Arrhythmogenesis

Can small changes in action potential duration have a major impact in human atrial electrophysiology? Listen as Associate Editor Mario Delmar (New York University) interviews authors Wayne Giles (University of Calgary) and Sanjiv Narayan (Stanford University) along with content expert Brian Delisle (University of Kentucky) about the new study by Ni et al. Combining mathematical modeling and clinical observations, Ni et al found that alternans could be strongly influenced by the types of potassium currents expressed in atrial myocytes, and that some potassium channel isoform switches occurring in atrial fibrillation may affect atrial physiology. The current study takes a reductionist approach to compare a single atrial control myocyte and a single myocyte in a-fib. What might the authors find if they replicate the isoform switch and study the conducted action potential in a 2-dimensional “sausage” of hundreds of myocytes? Listen and learn more.

 

Haibo Ni, Henggui Zhang, Eleonora Grandi, Sanjiv M. Narayan, and Wayne R. Giles Transient outward K+ current can strongly modulate action potential duration and initiate alternans in the human atrium Am J Physiol Heart Circ Physiol, published February 20, 2019. DOI: 10.1152/ajpheart.00251.2018