A detector for detecting a cardiac event in an IEGM has a bank of digital filters composed of at least two filters with substantially different impulse responses corresponding to different properties of the cardiac event. The filters respectively filter different portions of the IEGM and respectively emit a value per time unit corresponding to the morphological resemblance between the IEGM and the finite impulse response. An analyzing unit combines these output values from the filters in a predetermined manner for comparison with predetermined detection criteria.