title: Paradoxical atrial undersensing: noise rate reversion or amplifier ringing?
abstract: Atrial tachy-arrhythmias may give rise to mode switching or noise rate reversion in dual-chamber pacemakers. In case of high amplitude of the atrial electrogram during tachycardia, a paradoxical behavior of atrial sensitivity programming can be observed. Two patients with implanted dual-chamber pacemakers showed intermittent and complete loss of atrial sensing during atrial tachycardia during device programming to a higher atrial sensitivity setting. This phenomenon is caused by amplifier ringing and can be considered as a state of amplifier saturation, which disables atrial sensing in spite of the high amplitude of the atrial signal. In patients with high amplitude of the atrial electrogram during atrial tachycardia, a paradoxical behavior of sensitivity programming resulting in atrial undersensing can be observed.
authors.affiliation: Catharina Hospital, Eindhoven, The Netherlands. carlgr@cze.nl
authors.forename: Berry M
authors.initials: BM
authors.lastname: Van Gelder
authors.forename: Waldy
authors.initials: W
authors.lastname: Van Den Broek
authors.forename: Frank A
authors.initials: FA
authors.lastname: Bracke
authors.forename: Albert
authors.initials: A
authors.lastname: Meijer
mesh_terms: D000328:Adult; D000368:Aged; D000669:Amplifiers, Electronic; D016477:Artifacts; D004562:Electrocardiography / Q000379:methods*; D004868:Equipment Failure; D019544:Equipment Failure Analysis; D005188:False Negative Reactions; D006801:Humans; D008297:Male; D010138:Pacemaker, Artificial; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013612:Tachycardia, Ectopic Atrial / Q000175:diagnosis* / Q000517:prevention & control*