Using image registration to reconstruct spatiotemporal electrical activity in cardiac optical mapping studies

Optical mapping using membrane potential-sensitive fluorescent dyes provides a means of recording electrical activation on the heart surface with high spatial resolution. However, in order to interpret these data, it is necessary to correct for artifact introduced by heart wall motion. This paper describes a novel image registration technique that enables electrical activity on the heart surface to be reconstructed in the absence of pharmacological uncouplers commonly used to minimize heart wall motion. Image registration substantially reduced motion artifact and enabled activation times and action potential duration to be reconstructed accurately with respect to well-defined material points on the heart surface.