title: Retrospective analysis of mode survival, reliability of atrial sensing and incidence of atrial tachyarrhythmias in 307 single-lead VDD pacemaker patients.
abstract: OBJECTIVE
  The aim of this retrospective analysis was to investigate VDD mode survival, development of atrial tachyarrhythmias (AT), and long-term atrial sensing performance of VDD pacing systems.
  
  
  RESULTS
  We implanted single-lead VDD pacemakers in patients with isolated atrioventricular block and performed a retrospective analysis of 307 patients who had their devices implanted between May 1994 and September 2001. In 39 patients (12.7%), the pacing mode had to be reprogrammed to a single-chamber ventricular pacing mode, mostly due to permanent AT. In 16 of these patients, the atrial sensing safety margin was less than 150%. The atrial sensing safety margin was insufficient, i.e. less than 100% in only seven patients. Although only 12 (3.9%) of the patients had a history of paroxysmal AT at the time of pacemaker implantation, 200 (65%) patients presented with AT during follow-up. The mean AT burden at the last follow-up was 2.5%.
  
  
  CONCLUSIONS
  These data illustrate that single-lead VDD pacemakers can be applied without serious complications in a highly selected group of patients. Our main concern is the development of AT in a large part of our population. Over a 10-year period, two thirds of our patients presented with AT.
authors.affiliation: Department of Cardiology, University Medical Centre Ljubljana, Zaloska 7, 1000 Ljubljana, Slovenia. igor.zupan@mf.uni-lj.si
authors.forename: Igor
authors.initials: I
authors.lastname: Zupan
authors.forename: Luka
authors.initials: L
authors.lastname: Lipar
authors.forename: David
authors.initials: D
authors.lastname: Zizek
authors.forename: Wim
authors.initials: W
authors.lastname: Boute
authors.forename: Masa
authors.initials: M
authors.lastname: Vidmar
authors.forename: Tone
authors.initials: T
authors.lastname: Gabrijelcic
authors.forename: Peter
authors.initials: P
authors.lastname: Rakovec
authors.forename: Ales
authors.initials: A
authors.lastname: Brecelj
mesh_terms: D000368:Aged; D002304:Cardiac Pacing, Artificial / Q000379:methods; D005260:Female; D006327:Heart Block / Q000628:therapy; D006801:Humans; D008297:Male; D010138:Pacemaker, Artificial; D012189:Retrospective Studies; D013612:Tachycardia, Ectopic Atrial / Q000209:etiology*