title: Single lead atrial vs. dual chamber pacing in sick sinus syndrome: extended register-based follow-up in the DANPACE trial.
abstract: OBJECTIVE
  The DANPACE trial randomized patients with sick sinus syndrome (SSS) to single lead atrial (AAIR) or dual chamber (DDDR) pacemaker (PM). After 5 years follow-up, no difference in overall survival, stroke or heart failure (HF) was observed, whereas risk of atrial fibrillation (AF) and PM reoperation were increased in the AAIR group. The present study aimed to investigate very long term risk of death, AF hospitalization, stroke, HF and rate of change in pacing mode using national register-based data.
  
  
  RESULTS
  The study population consisted of all 1384 patients included at Danish PM centres in the DANPACE trial randomized to AAIR (n = 696) or DDDR (n = 688). Long-term follow-up data was obtained from Danish national registers. Analysis was intention-to-treat. results: During mean follow-up of 8.9 years, 413 patients (59.3%) died in the AAIR-group compared to 367 (53.3%) in the DDDR-group (adjusted hazard ratio 1.03; 95% confidence interval 0.90-1.19; P = 0.65). We observed no difference in risk of AF hospitalization, stroke or HF. During extended follow-up, annual rate of pacing mode change to DDDR in the AAIR group was 4.5%, and higher than the 2.3% observed during trial conduct.
  
  
  CONCLUSIONS
  This register-based long-term follow-up study indicates that there is no difference in mortality among patients with SSS randomized to AAIR or DDDR pacing, even with very long follow-up. Nor is there any difference in risk of AF hospitalization, stroke or HF. The higher rate of pacing mode-change to DDDR in the AAIR group suggests a different management of patients with an AAIR PM after the DANPACE trial.
authors.affiliation: Department of Cardiology, Zealand University Hospital, Roskilde, Denmark.
authors.forename: Niels H
authors.initials: NH
authors.lastname: Brandt
authors.affiliation: Department of Cardiology, Aarhus University Hospital, Skejby, Denmark.
authors.forename: Rikke Esberg
authors.initials: RE
authors.lastname: Kirkfeldt
authors.affiliation: Department of Cardiology, Aarhus University Hospital, Skejby, Denmark.
authors.forename: Jens Cosedis
authors.initials: JC
authors.lastname: Nielsen
authors.affiliation: UNI-C, Aarhus, Denmark.
authors.forename: Leif Spange
authors.initials: LS
authors.lastname: Mortensen
authors.affiliation: Department of Cardiology, Zealand University Hospital, Roskilde, Denmark.
authors.forename: Gunnar Vagn Hagemann
authors.initials: GVH
authors.lastname: Jensen
authors.affiliation: Odense University Hospital, Odense S, Denmark.
authors.forename: Jens Brock
authors.initials: JB
authors.lastname: Johansen
authors.affiliation: Department of Cardiology, Zealand University Hospital, Roskilde, Denmark.|Department of Cardiology, Rigshospitalet, Copenhagen, Denmark.
authors.forename: Ketil
authors.initials: K
authors.lastname: Haugan
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000209:etiology; D002304:Cardiac Pacing, Artificial / Q000009:adverse effects / Q000379:methods* / Q000401:mortality; D016009:Chi-Square Distribution; D003718:Denmark; D005260:Female; D006333:Heart Failure / Q000209:etiology; D006801:Humans; D057194:Intention to Treat Analysis; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial; D016016:Proportional Hazards Models; D012042:Registries; D012307:Risk Factors; D012804:Sick Sinus Syndrome / Q000150:complications / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D020521:Stroke / Q000209:etiology; D013997:Time Factors; D016896:Treatment Outcome
keywords: Dual chamber pacing; Pacemaker; Randomized clinical trial; Register-based; Sick sinus syndrome; Single lead atrial pacing