Abstract: An electrode arrangement (10) comprising a first electrode cable (12) which is to be inserted into the coronary sinus and which has an electrode conductor (32) and at least one electrode (38, 40) for outputting and/or receiving electrical signals in the coronary sinus. Longitudinally slidably guidable in the lumen of the first electrode cable (12) at least in a longitudinal portion-wise manner is a second electrode cable (14) which can issue from the first electrode cable through an opening (52) at the distal end thereof and which is adapted for insertion into a cardiac vein which opens into the coronary sinus.