Secondary SR Ca2+ Release and Arrhythmia Risk in Bradycardia

Our latest podcast explores the newly published article by Kim et al. In this work, lead author Guy Salama (University of Pittsburgh) and colleagues found that by prolonging action-potential duration, bradycardia may destabilize calcium and cause arrhythmia. Associate Editor Igor Efimov leads an engaging discussion with Salama and expert Steven Poelzing (Virginia Tech) about how intracellular calcium can affect cardiac electrophysiology, and through calcium-voltage coupling, can become the original source of arrhythmia. We also take a look at gender differences in remodeling and arrhythmogenesis, and the possible role estrogen may play in the susceptibility of the female heart to bradycardia-mediated arrhythmias.

Jong J. Kim, Jan Nemec, Rita Papp, Robert Strongin, Jonathan J Abramson, and Guy Salama Bradycardia alters Ca2+ dynamics which enhances dispersion of repolarization and arrhythmia risk Am J Physiol Heart Circ Physiol, published online January 11, 2013, doi: 10.1152/ajpheart.00787.2012.