Differential Expression and Remodeling of Transient Outward Potassium Currents in Human Left Ventricles

Abstract

<i>I</i>_to,f and <i>I</i>_to,s are differentially expressed in nonfailing human LV, contributing to regional heterogeneities in AP waveforms. <i>I</i>_to,f regulates notch and plateau potentials and modulates the time course and amplitude of <i>I</i>_Ca. Slowing <i>I</i>_to,f inactivation results in dramatic AP shortening. Remodeling of <i>I</i>_to,f in failing human LV subepicardial myocytes attenuates transmural differences in AP waveforms.