Acute Glycogen Synthase Kinase-3 Inhibition Modulates Human Cardiac Conduction

•Human cardiac slices cultured with SB216763 showed reduced conduction velocity and decreased excitability, as measured by dVm/dtmax, at 3 and 24 hours compared to slices cultured in control media.•Both overall and nuclear β-catenin levels increased, whereas NaV1.5 decreased, in human cardiac slices cultured with SB216763.•Induced stabilization of β-catenin in adult murine hearts decreases conduction velocity and increases susceptibility to arrhythmias.