Patent ID: 7593766

Claim:
A detector for atrial fibrillation and/or atrial flutter comprising: an atrial input configured to receive an atrial signal representing an intraatrial electrogram or a time course of an intraatrial impedance; a ventricular input configured to receive a ventricular event signal comprising information on an occurrence of a cyclically reoccurring ventricular event in chronological association to said atrial signal received via said atrial input; an averaging unit that is configured to average a plurality of sections of said atrial signal, each section to be considered for averaging starts at a predefined offset with respect to a ventricular event and ends at the predefined offset before a next ventricular event, and wherein said averaging unit is further configured to put out an average atrial signal; a peak amplitude determination unit that is configured to determine a peak-to-peak amplitude of said averaged atrial signal; and, a threshold comparator that is configured to compare said peak-to-peak amplitude of said averaged atrial signal to a predetermined reference value and to generate an AF warning signal if said peak-to-peak amplitude of said averaged atrial signal is less than said predetermined reference value.