A method is disclosed for visualizing at least one section of the wall of an atrium (21) of the heart in a patient (P) after an ablation for treating atrial fibrillation, in which, based on a volume data record of the heart in the patient (P) obtained after the ablation, at least the treated atrium (21) of the heart in the patient (P) is segmented, wherein those voxels are established that can be considered part of the inner surface (25), the outer surface (26), and the volume (27) situated between the inner (25) and outer surfaces (26) of the wall of the treated atrium (21). Further, in at least one embodiment of the method, there is volume rendering or ray casting such that only the voxel values of those voxels that lie on the inner surface (25), in the volume (27), or on the outer surface (26) of the wall of the treated atrium (21) are used for visualizing at least the section of the wall of the treated atrium (21) of the heart. At least one embodiment of the invention moreover relates to a computational program (13) that executes the method, a computational unit (12) that carries out the computational program, and / or a data medium (14, 15) with the computational program.