title: Pacing in elderly recurrent fallers with carotid sinus hypersensitivity: a randomised, double-blind, placebo controlled crossover trial.
abstract: OBJECTIVE
  While carotid sinus syndrome (CSS) is traditionally defined by the association of carotid sinus hypersensitivity (CSH) with syncope, uncertainty remains over the role, if any, of complex pacing in patients with CSH and unexplained or recurrent falls. We sought to clarify the role of dual chamber pacing in this patient group in the first placebo-controlled study in CSH.
  
  
  METHODS
  Randomised, double-blind, crossover, placebo-controlled trial.
  
  
  METHODS
  Specialist falls and syncope facility.
  
  
  METHODS
  Consecutive subjects aged over 55 years with CSH as the sole attributable cause of three or more unexplained falls in the 6 months preceding enrolment.
  
  
  METHODS
  Dual-chamber permanent pacing with rate-drop response programming. The pacemaker was switched on (DDD/RDR) or off (ODO (placebo)) for 6 months, then crossed over to the alternate mode for a further 6 months, in randomised, double-blind fashion.
  
  
  METHODS
  The primary outcome measure was number of falls in paced and non-paced modes.
  
  
  RESULTS
  Twenty-five of 34 subjects (mean 76.8 years (SD 9.0), 27 (79%) female) recruited completed the study. Pacing intervention had no effect on number of falls (4.04 (9.54) in DDD/RDR mode, 3.48 (7.22) in ODO; relative risk of falling in ODO mode 0.82, 95% CI 0.62 to 1.10).
  
  
  CONCLUSIONS
  Permanent pacing intervention had no effect on fall rates in older patients with CSH. Further work is urgently needed to clarify the role, if any, of complex pacing in this patient group.
authors.affiliation: Falls and Syncope Service, Royal Victoria Infirmary, Queen Victoria Road, Newcastle upon Tyne, UK. swparry@hotmail.com
authors.forename: S W
authors.initials: SW
authors.lastname: Parry
authors.forename: N
authors.initials: N
authors.lastname: Steen
authors.forename: R S
authors.initials: RS
authors.lastname: Bexton
authors.forename: M
authors.initials: M
authors.lastname: Tynan
authors.forename: R A
authors.initials: RA
authors.lastname: Kenny
mesh_terms: D000058:Accidental Falls / Q000401:mortality / Q000706:statistics & numerical data*; D000368:Aged; D000369:Aged, 80 and over; D002304:Cardiac Pacing, Artificial / Q000401:mortality / Q000706:statistics & numerical data*; D002346:Carotid Sinus / Q000503:physiopathology; D004812:Epidemiologic Methods; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D010138:Pacemaker, Artificial; D013575:Syncope / Q000150:complications* / Q000401:mortality / Q000503:physiopathology / Q000601:surgery; D013577:Syndrome