title: Reverse atrial electrical remodelling induced by continuous positive airway pressure in patients with severe obstructive sleep apnoea.
abstract: BACKGROUND
  Obstructive sleep apnoea (OSA) is associated with cardiovascular morbidity and mortality, including atrial arrhythmias. Continuous positive airway pressure (CPAP) is the gold standard treatment for OSA; its impact on atrial electrical remodelling has not been fully investigated. Signal-averaged p-wave (SAPW) duration is an accepted marker for atrial electrical remodelling.
  
  
  OBJECTIVE
  The objective of this study is to determine whether CPAP induces reverse atrial electrical remodelling in patients with severe OSA.
  
  
  METHODS
  Consecutive patients attending the Sleep Disorder Clinic at Kingston General Hospital underwent full polysomnography. OSA-negative controls and severe OSA were defined as apnoea-hypopnea index (AHI) < 5 events/hour and AHI ≥ 30 events/hour, respectively. SAPW duration was determined at baseline and after 4-6 weeks of CPAP in severe OSA patients or without intervention controls.
  
  
  RESULTS
  Nineteen severe OSA patients and 10 controls were included in the analysis. Mean AHI and minimum oxygen saturation were 41.4 ± 10.1 events/hour and 80.5 ± 6.5 % in severe OSA patients and 2.8 ± 1.2 events/hour and 91.4 ± 2.1 % in controls. At baseline, severe OSA patients had a greater SAPW duration than controls (131.9 ± 10.4 vs 122.8 ± 10.5 ms; p = 0.02). After CPAP, there was a significant reduction of SAPW duration in severe OSA patients (131.9 ± 10.4 to 126.2 ± 8.8 ms; p < 0.001), while SAPW duration did not change after 4-6 weeks in controls.
  
  
  CONCLUSIONS
  CPAP induced reverse atrial electrical remodelling in patients with severe OSA as represented by a significant reduction in SAPW duration.
authors.affiliation: Cardiology Division, Kingston General Hospital, Queen's University, Kingston, ON, Canada. barancha@kgh.kari.net
authors.forename: Adrian
authors.initials: A
authors.lastname: Baranchuk
authors.forename: Helen
authors.initials: H
authors.lastname: Pang
authors.forename: Geoffrey E J
authors.initials: GE
authors.lastname: Seaborn
authors.forename: Payam
authors.initials: P
authors.lastname: Yazdan-Ashoori
authors.forename: Damian P
authors.initials: DP
authors.lastname: Redfearn
authors.forename: Christopher S
authors.initials: CS
authors.lastname: Simpson
authors.forename: Kevin A
authors.initials: KA
authors.lastname: Michael
authors.forename: Michael
authors.initials: M
authors.lastname: Fitzpatrick
mesh_terms: D000222:Adaptation, Physiological; D045422:Continuous Positive Airway Pressure; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D006325:Heart Atria / Q000503:physiopathology*; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D020181:Sleep Apnea, Obstructive / Q000503:physiopathology* / Q000534:rehabilitation*; D016896:Treatment Outcome