Disclosed are devices, systems, and methods for determining the dipole densities on heart walls. In particular, a triangularization of the heart wall is performed in which the dipole density of each of multiple regions correlate to the potential measured at various located within the associated chamber of the heart. To create a database of dipole densities, mapping information recorded by multiple electrodes located on one or more catheters and anatomical information is used. In addition, skin electrodes may be implemented. Additionally, one or more ultrasound elements are provided, such as on a clamp assembly or integral to a mapping electrode, to produce real time images of device components and surrounding structures.