Abstract: A method for identifying radiotherapy targets for treating cardiac arrhythmias, which comprises: receiving at least one 3D mapping of points each associated with at least one given feature of a patient's heart and receiving locations of at least one area to be protected, said locations being spatially registered within the reference frame of the 3D mapping; segmenting at least a region in said at least one 3D mapping with selecting a plurality of points of the 3D mapping whose at least one associated given feature matches a predetermined criterion; cropping said segmented region in the 3D mapping with unselecting a plurality of points of the segmented region whose distance to said area to be protected is lower than a predetermined threshold; generating a 3D volumetric model comprising a mesh computed from said cropped region and identified to said cropped region and storing said 3D volumetric model in an electronic file.