title: Long-term outcome of single-chamber atrial pacing compared with dual-chamber pacing in patients with sinus-node dysfunction and intact atrioventricular node conduction.
abstract: OBJECTIVE
  The optimal pacing mode with either single chamber atrial pacemaker (AAI or AAIR) or dual chamber pacemaker (DDD or DDDR) is still not clear in sinus-node dysfunction (SND) and intact atrioventricular (AV) conduction.
  
  
  METHODS
  Patients who were implanted with permanent pacemaker using AAI(R) (n = 73) or DDD(R) (n = 113) were compared.
  
  
  RESULTS
  The baseline characteristics were comparable between the two groups, with a mean follow-up duration of 69 months. The incidence of death did not show statistical difference. However, the incidence of hospitalization for congestive heart failure (CHF) was significantly lower in the AAI(R) group (0%) than the DDD(R) group (8.8%, p = 0.03). Also, atrial fibrillation (AF) was found in 2.8% in the AAI(R) group, which was statistically different from 15.2% of patients in the DDD(R) group (p = 0.01). Four patients (5.5%) with AAI(R) developed AV block, and subsequently switched to DDD(R) pacing. The risk of AF was lower in the patients implanted with AAI(R) than those with DDD(R) [hazard ratio (HR), 0.84; 95% confidence interval, 0.72 to 0.97, p = 0.02].
  
  
  CONCLUSIONS
  In patients with SND and intact AV conduction, AAI(R) pacing can achieve a better clinical outcome in terms of occurrence of CHF and AF than DDD(R) pacing. These findings support AAI(R) pacing as the preferred pacing mode in patients with SND and intact AV conduction.
authors.affiliation: Division of Cardiology, Eulji University Hospital, Eulji University School of Medicine, Daejeon, Korea.
authors.forename: Won Ho
authors.initials: WH
authors.lastname: Kim
authors.forename: Boyoung
authors.initials: B
authors.lastname: Joung
authors.forename: Jaemin
authors.initials: J
authors.lastname: Shim
authors.forename: Jong Sung
authors.initials: JS
authors.lastname: Park
authors.forename: Eui-Seock
authors.initials: ES
authors.lastname: Hwang
authors.forename: Hui-Nam
authors.initials: HN
authors.lastname: Pak
authors.forename: Sungsoon
authors.initials: S
authors.lastname: Kim
authors.forename: Moonhyoung
authors.initials: M
authors.lastname: Lee
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000150:complications / Q000503:physiopathology; D001283:Atrioventricular Node / Q000503:physiopathology*; D002304:Cardiac Pacing, Artificial; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000150:complications; D006801:Humans; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012804:Sick Sinus Syndrome / Q000503:physiopathology*; D016896:Treatment Outcome