Skip to main content
Article thumbnail
Location of Repository

Single-chamber versus dual-chamber pacing for high-grade atrioventricular block

By W. D. Toff, A. J. Camm, J. D. Skehan and United Kingdom Pacing and Cardiovascular Events Trial Investigators.


background\ud In the treatment of atrioventricular block, dual-chamber cardiac pacing is thought to\ud confer a clinical benefit as compared with single-chamber ventricular pacing, but the\ud supporting evidence is mainly from retrospective studies. Uncertainty persists regarding\ud the true benefits of dual-chamber pacing, particularly in the elderly, in whom it is\ud used less often than in younger patients.\ud methods\ud In a multicenter, randomized, parallel-group trial, 2021 patients 70 years of age or\ud older who were undergoing their first pacemaker implant for high-grade atrioventricular\ud block were randomly assigned to receive a single-chamber ventricular pacemaker\ud (1009 patients) or a dual-chamber pacemaker (1012 patients). In the singlechamber\ud group, patients were randomly assigned to receive either fixed-rate pacing\ud (504 patients) or rate-adaptive pacing (505 patients). The primary outcome was death\ud from all causes. Secondary outcomes included atrial fibrillation, heart failure, and a composite\ud of stroke, transient ischemic attack, or other thromboembolism.\ud results\ud The median follow-up period was 4.6 years for mortality and 3 years for other cardiovascular\ud events. The mean annual mortality rate was 7.2 percent in the single-chamber\ud group and 7.4 percent in the dual-chamber group (hazard ratio, 0.96; 95 percent confidence\ud interval, 0.83 to 1.11). We found no significant differences between the group\ud with single-chamber pacing and that with dual-chamber pacing in the rates of atrial\ud fibrillation, heart failure, or a composite of stroke, transient ischemic attack, or other\ud thromboembolism.\ud conclusions\ud In elderly patients with high-grade atrioventricular block, the pacing mode does not\ud influence the rate of death from all causes during the first five years or the incidence of\ud cardiovascular events during the first three years after implantation of a pacemaker

Publisher: Massachusetts Medical Society
Year: 2005
DOI identifier: 10.1056/NEJMoa042283
OAI identifier:

Suggested articles


  1. Bartholomew’s Hospital,
  2. Cardiothoracic Centre, doi
  3. City Hospital,
  4. County Hospital,
  5. (1998). Data Management Center (Nottingham Clinical Research Group)
  6. Derbyshire Royal Infirmary,
  7. Derriford Hospital,
  8. Freeman Hospital,
  9. Glan Clywd Hospital,
  10. Glasgow Royal Infirmary,
  11. Good Hope Hospital,
  12. Hairmyres Hospital,
  13. Heartlands Hospital,
  14. Hull Royal Infirmary,
  15. Ipswich Hospital,
  16. Maelor Hospital,
  17. Millane; Doncaster Royal Infirmary, doi
  18. Ninewells Hospital,
  19. Papworth Hospital,
  20. Queen Elizabeth Hospital,
  21. Queen’s Medical Centre,
  22. Royal Devon and Exeter Hospital, doi
  23. Royal Free Hospital,
  24. Royal Sussex County Hospital,
  25. Sandwell Hospital,
  26. Solihull Hospital,
  27. Southern General Hospital,
  28. St George’s Hospital,
  29. Stafford General Hospital,
  30. Stobhill Hospital,
  31. (1990). Superior cardiac hemodynamics of atrioventricular synchrony over rate responsive pacing at submaximal exercise: observations in activity sensing DDDR pacemakers. Pacing Clin Electrophysiol doi
  32. The General Infirmary,
  33. Treliske Hospital,
  34. Trial Steering Committee — S.M. Cobbe
  35. UCH/Middlesex Hospitals,
  36. Wansbeck General Hospital,
  37. Wessex Cardiothoracic Centre,
  38. Wordsley Hospital,

To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.