1. A method for visually supporting an electrophysiology catheter application in the heart, comprising: visualizing electroanatomical 3D mapping data, provided during the performance of the catheter application, of an area of the heart to be treated; recording 3D image data of the area to be treated with a method of tomographical 3D imaging before the catheter application is carried out; extracting a 3D surface profile of objects in the area to be treated from the 3D image data by segmentation; and visualizing the electroanatomical 3D mapping data and 3D image data representing at least the 3D surface profile by registration correctly correlated in position and dimension and superimposed upon one another, the correlation in the correct position and dimension being automatically effected by the surface matching, at least in one stage of the registration, the 3D surface profile from the 3D image data being at least approximately brought to match a 3D surface profile from the 3D mapping data.