title: A comparison of single-lead atrial pacing with dual-chamber pacing in sick sinus syndrome.
abstract: OBJECTIVE
  In patients with sick sinus syndrome, bradycardia can be treated with a single-lead pacemaker or a dual-chamber pacemaker. Previous trials have revealed that pacing modes preserving atrio-ventricular synchrony are superior to single-lead ventricular pacing, but it remains unclear if there is any difference between single-lead atrial pacing (AAIR) and dual-chamber pacing (DDDR).
  
  
  RESULTS
  We randomly assigned 1415 patients referred for first pacemaker implantation to AAIR (n = 707) or DDDR (n = 708) pacing and followed them for a mean of 5.4 ± 2.6 years. The primary outcome was death from any cause. Secondary outcomes included paroxysmal and chronic atrial fibrillation, stroke, heart failure, and need for pacemaker reoperation. In the AAIR group, 209 patients (29.6%) died during follow-up vs. 193 patients (27.3%) in the DDDR group, hazard ratio (HR) 1.06, 95% confidence interval (CI) 0.88-1.29, P = 0.53. Paroxysmal atrial fibrillation was observed in 201 patients (28.4%) in the AAIR group vs. 163 patients (23.0%) in the DDDR group, HR 1.27, 95% CI 1.03-1.56, P = 0.024. A total of 240 patients underwent one or more pacemaker reoperations during follow-up, 156 (22.1%) in the AAIR group vs. 84 (11.9%) in the DDDR group (HR 1.99, 95% CI 1.53-2.59, P < 0.001). The incidence of chronic atrial fibrillation, stroke, and heart failure did not differ between treatment groups.
  
  
  CONCLUSIONS
  In patients with sick sinus syndrome, there is no statistically significant difference in death from any cause between AAIR pacing and DDDR pacing. AAIR pacing is associated with a higher incidence of paroxysmal atrial fibrillation and a two-fold increased risk of pacemaker reoperation. These findings support the routine use of DDDR pacing in these patients.
  
  
  BACKGROUND
  URL http://www.clinicaltrials.gov. Unique identifier: NCT00236158.
authors.affiliation: Department of Cardiology B, Aarhus University Hospital, Skejby, Aarhus N, Denmark. jenniels@rm.dk
authors.forename: Jens Cosedis
authors.initials: JC
authors.lastname: Nielsen
authors.forename: Poul Erik B
authors.initials: PE
authors.lastname: Thomsen
authors.forename: Søren
authors.initials: S
authors.lastname: Højberg
authors.forename: Mogens
authors.initials: M
authors.lastname: Møller
authors.forename: Thomas
authors.initials: T
authors.lastname: Vesterlund
authors.forename: Dorthe
authors.initials: D
authors.lastname: Dalsgaard
authors.forename: Leif S
authors.initials: LS
authors.lastname: Mortensen
authors.forename: Tonny
authors.initials: T
authors.lastname: Nielsen
authors.forename: Mogens
authors.initials: M
authors.lastname: Asklund
authors.forename: Elsebeth V
authors.initials: EV
authors.lastname: Friis
authors.forename: Per D
authors.initials: PD
authors.lastname: Christensen
authors.forename: Erik H
authors.initials: EH
authors.lastname: Simonsen
authors.forename: Ulrik H
authors.initials: UH
authors.lastname: Eriksen
authors.forename: Gunnar V H
authors.initials: GV
authors.lastname: Jensen
authors.forename: Jesper H
authors.initials: JH
authors.lastname: Svendsen
authors.forename: William D
authors.initials: WD
authors.lastname: Toff
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Healey
authors.forename: Henning R
authors.initials: HR
authors.lastname: Andersen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000209:etiology / Q000401:mortality; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D002316:Cardiotonic Agents / Q000627:therapeutic use; D002423:Cause of Death; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial; D012086:Reoperation / Q000706:statistics & numerical data; D012804:Sick Sinus Syndrome / Q000401:mortality / Q000628:therapy*; D020521:Stroke / Q000209:etiology / Q000401:mortality; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D002316:Cardiotonic Agents