title: Cardiac resynchronization therapy for the treatment of sleep apnoea: a meta-analysis.
abstract: OBJECTIVE
  Sleep apnoea (SA) is a common problem among congestive heart failure (CHF) patients. Evidence has shown that cardiac resynchronization therapy (CRT) reduces morbidity and mortality associated with CHF. The aim of this paper was to review studies evaluating the reduction of the Apnoea-Hypopnoea Index (AHI) in patients with SA after treatment with CRT and to perform a meta-analysis to estimate the true effect of CRT on SA.
  
  
  RESULTS
  A systematic electronic literature search was conducted in Medline and Embase to identify studies reporting on the effects of CRT on SA. A hand search of five major cardiology societies was performed to identify any unpublished studies through structured abstracts submitted to conference proceedings. To be eligible for inclusion, studies had to include a comparison of CRT vs. no pacing and use AHI as an outcome. Non-English studies were excluded. Nine manuscripts and five abstracts were identified for review. Six manuscripts and three abstracts were included in meta-analysis, which included 170 patients. After treatment with CRT, a significant reduction in AHI was found in patients with central sleep apnoea (CSA) with a mean reduction of -13.05 (CI -16.74 to -9.36; P < 0.00001) but not in patients with obstructive sleep apnoea (13.32; CI -9.04 to 2.39; P = 0.25).
  
  
  CONCLUSIONS
  Cardiac resynchronization therapy reduces the severity of SA. Major effects are seen in patients with CSA. The presence of SA may be an additional consideration when deciding on which heart failure patients will receive CRT.
authors.affiliation: Department of Medicine and Physiology, Cardiac Electrophysiology and Pacing, Kingston General Hospital, Queen's University, Kingston, K7L 2V7 Ontario, Canada.
authors.forename: Jasmine
authors.initials: J
authors.lastname: Lamba
authors.forename: Christopher S
authors.initials: CS
authors.lastname: Simpson
authors.forename: Damian P
authors.initials: DP
authors.lastname: Redfearn
authors.forename: Kevin A
authors.initials: KA
authors.lastname: Michael
authors.forename: Michael
authors.initials: M
authors.lastname: Fitzpatrick
authors.forename: Adrian
authors.initials: A
authors.lastname: Baranchuk
mesh_terms: D016275:Atrial Function / Q000502:physiology; D058406:Cardiac Resynchronization Therapy / Q000379:methods*; D006333:Heart Failure / Q000150:complications* / Q000628:therapy*; D006801:Humans; D012891:Sleep Apnea Syndromes / Q000209:etiology* / Q000628:therapy*; D016896:Treatment Outcome