Images of action potential propagation in heart

Activation and repolarization across mammalian hearts follow complex three- dimensional pathways that are governed by fiber structure, intercellular co upling, and action potentials (APs) with spatially heterogeneous properties . Voltage-sensitive dyes and imaging techniques offer new insights on how s patiotemporal heterogeneities of APs govern propagation, repolarization, an d AV node conduction and help us visualize arrhythmias with previously unat tainable details.