title: Automatic measurement of atrial pacing thresholds in dual-chamber pacemakers: clinical experience with atrial capture management.
abstract: BACKGROUND
  The Medtronic EnPulse pacemaker incorporates the new atrial capture management (ACM) algorithm to automatically measure atrial capture thresholds and subsequently manage atrial pacing outputs.
  
  
  OBJECTIVE
  The purpose of this study was to evaluate the clinical performance of ACM.
  
  
  METHODS
  Two hundred patients with an indication for a dual-chamber pacemaker underwent implantation. ACM thresholds and manually measured atrial pacing thresholds were assessed at follow-up visits. Clinical equivalence was defined as the ACM-measured threshold being within -0.25 V to +0.5 V of the manually measured threshold. The clinician analyzed all ACM measurements performed in-office for evidence of proarrhythmia.
  
  
  RESULTS
  All 200 implanted patients had a 1-month visit, and validated manual and in-office ACM threshold data were available for 123 patients. The ACM threshold was 0.595 +/- 0.252 V, and the manual threshold was 0.584 +/- 0.233 V. The mean difference was 0.010 V with a 95% confidence interval of (-0.001, 0.021). The mean difference over all visits was 0.011 V. For all patients, the individual threshold differences were within the range of clinical equivalence at all visits. No atrial arrhythmias were observed during 892 ACM tests in 193 patients.
  
  
  CONCLUSIONS
  This study demonstrated that the ACM algorithm is safe, accurate, and reliable over time. ACM was demonstrated to be clinically equivalent to the manual atrial threshold test in all patients at 1 month and over the entire follow-up period of up to 6 months. ACM ensures atrial capture, may save time during follow-up, and can be used to manage atrial pacing outputs.
authors.affiliation: Kerckhoff Klinik, Kardiologie, Benekestrasse 2-8, 61231 Bad Nauheim, Germany. j.sperzel@kerckhoff-klinik.de
authors.forename: Johannes
authors.initials: J
authors.lastname: Sperzel
authors.forename: Goran
authors.initials: G
authors.lastname: Milasinovic
authors.forename: Timothy W
authors.initials: TW
authors.lastname: Smith
authors.forename: Hardwin
authors.initials: H
authors.lastname: Mead
authors.forename: Johan
authors.initials: J
authors.lastname: Brandt
authors.forename: Wesley K
authors.initials: WK
authors.lastname: Haisty
authors.forename: J Russell
authors.initials: JR
authors.lastname: Bailey
authors.forename: Marc
authors.initials: M
authors.lastname: Roelke
authors.forename: Jay
authors.initials: J
authors.lastname: Simonson
authors.forename: Jennifer
authors.initials: J
authors.lastname: Englund
authors.forename: Eric
authors.initials: E
authors.lastname: Farges
authors.forename: Steven
authors.initials: S
authors.lastname: Compton
mesh_terms: D000368:Aged; D001145:Arrhythmias, Cardiac / Q000503:physiopathology / Q000628:therapy*; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D004562:Electrocardiography; D004567:Electrodes, Implanted; D004867:Equipment Design; D005260:Female; D005500:Follow-Up Studies; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D010138:Pacemaker, Artificial; D011446:Prospective Studies; D016896:Treatment Outcome