title: Effects of continuous and triggered atrial overdrive pacing on paroxysmal atrial fibrillation in pacemaker patients.
abstract: BACKGROUND
  The aim of the study was to compare the effects of different pacing strategies to prevent paroxysmal atrial fibrillation (AF): triggered atrial overdrive pacing versus the combination of triggered and continuous overdrive pacing.
  
  
  METHODS
  Patients with an indication for dual-chamber pacing (Selection 9000, Prevent AF; Vitatron B.V., Arnhem, the Netherlands) and a history of paroxysmal AF were randomized to triggered atrial pacing (three pacing functions, "triggered group": PAC Suppression, Post-PAC Response, and Post-Exercise Response) or to the combination of continuous (Pace Conditioning) and triggered atrial pacing (four pacing functions, "combined group"). After 3 months, there was a crossover to the other pacemaker setting.
  
  
  RESULTS
  In 171 enrolled patients, the median AF burden of the combined group was with 2.1% versus 0.1% in the triggered group (P = 0.014). Fewer AF episodes were observed in the triggered (median: 7) than in the combined group (median: 116; P = 0.016). The combined group had more frequent atrial pacing (median 97%) than the triggered group with 85% (P < 0.001), but ventricular pacing was not significantly different with 95% and 96% in the combined and triggered group, respectively. After the crossover, the AF burden increased in the triggered group to 0.3% and decreased in the combined group to 0.4%.
  
  
  CONCLUSIONS
  Triggered atrial pacing functions alone resulted in a low AF burden. The additional activation of continuous atrial overdrive pacing increased the percentage of atrial pacing, but had no beneficial effects on the prevention of paroxysmal AF.
authors.affiliation: Medical Clinic, Friedrich-Ebert Hospital, Neumünster, Germany. andreas.schuchert@fek.de
authors.forename: Andreas
authors.initials: A
authors.lastname: Schuchert
authors.forename: Hans-Peter
authors.initials: HP
authors.lastname: Rebeski
authors.forename: Thomas
authors.initials: T
authors.lastname: Peiffer
authors.forename: Eberhard
authors.initials: E
authors.lastname: Bub
authors.forename: Armin
authors.initials: A
authors.lastname: Dietz
authors.forename: Kai
authors.initials: K
authors.lastname: Mortensen
authors.forename: Mohammed Ali
authors.initials: MA
authors.lastname: Aydin
authors.forename: John
authors.initials: J
authors.lastname: Camm
authors.forename: Steffen
authors.initials: S
authors.lastname: Gazarek
authors.forename: Thomas
authors.initials: T
authors.lastname: Meinertz
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000453:epidemiology* / Q000517:prevention & control*; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D010138:Pacemaker, Artificial / Q000706:statistics & numerical data*; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors