1. A device ( 10 ) for processing electrocardiogram signals and marker signals including: a. an input interface ( 30 ) receiving electrocardiogram signals and marker signals detected by an implantable medical device; b. an analyzer unit ( 32 ) connected to the input interface ( 30 ), the analyzer unit ( 32 ): (1) processing the electrocardiogram signals and marker signals, (2) detecting particular features in one or more of the electrocardiogram signals and marker signals on the basis of predefined detection criteria, (3) assigning priority rankings to detected particular features, (4) generating analyzer marker signals marking at least some of the detected particular features of the electrocardiogram signals, and (5) comparing the input marker signals and analyzer marker signals for differences; and c. an output interface ( 34 ) connected to the analyzer unit ( 32 ), the output interface ( 34 ) outputting data representing an analytical report, the analytical report containing at least a listing of the detected particular features.