A method includes accepting a plurality of Magnetic Resonance Imaging (MRI) data points of a cardiac chamber, acquired over multiple phases of at least one cardiac cycle. A simulated surface of the cardiac chamber is constructed by processing the MRI data points. Measurements of a parameter, acquired at respective points on a surface of the cardiac chamber, are accepted from an intra-cardiac probe. The measurements are overlaid on the simulated surface constructed from the MRI data points, so as to produce a map of the parameter on the surface.
