Amir Toib, Chen Zhang, Giulia Borghetti, Xiaoxiao Zhang, Markus Wallner, Yijun Yang, Constantine D Troupes, Hajime Kubo, Thomas E Sharp, Eric Feldsott, Remus M Berretta, Neil Zalavadia, Danielle M Trappanese, Shavonn Harper, Polina Gross, Xiongwen Chen, Sadia Mohsin, Steven R Houser
Hypertrophic cardiomyopathy (HCM) is one of the most common genetic cardiac diseases and among the leading causes of sudden cardiac death (SCD) in the young. The cellular mechanisms leading to SCD in HCM are not well known. Prolongation of the action potential (AP) duration (APD) is a common feature predisposing hypertrophied hearts to SCD. Previous studies have explored the roles of inward Na+ and Ca2+ in the development of HCM, but the role of repolarizing K+ currents has not been defined. The objective of this study was to characterize the arrhythmogenic phenotype and cellular electrophysiological properties of mice with HCM, induced by myosin-binding protein C (MyBPC) knockout (KO), and to test the hypothesis that remodeling of repolarizing K+ currents causes APD prolongation in MyBPC KO myocytes...
September 1, 2017: American Journal of Physiology. Heart and Circulatory Physiology