title: Simulated Obstructive Sleep Apnea Increases P-Wave Duration and P-Wave Dispersion.
abstract: BACKGROUND
  A high P-wave duration and dispersion (Pd) have been reported to be a prognostic factor for the occurrence of paroxysmal atrial fibrillation (PAF), a condition linked to obstructive sleep apnea (OSA). We tested the hypothesis of whether a short-term increase of P-wave duration and Pd can be induced by respiratory manoeuvres simulating OSA in healthy subjects and in patients with PAF.
  
  
  METHODS
  12-lead-electrocardiography (ECG) was recorded continuously in 24 healthy subjects and 33 patients with PAF, while simulating obstructive apnea (Mueller manoeuvre, MM), obstructive hypopnea (inspiration through a threshold load, ITH), central apnea (AP), and during normal breathing (BL) in randomized order. The P-wave duration and Pd was calculated by using dedicated software for ECG-analysis.
  
  
  RESULTS
  P-wave duration and Pd significantly increased during MM and ITH compared to BL in all subjects (+13.1 ms and +13.8 ms during MM; +11.7 ms and +12.9 ms during ITH; p<0.001 for all comparisons). In MM, the increase was larger in healthy subjects when compared to patients with PAF (p<0.05).
  
  
  CONCLUSIONS
  Intrathoracic pressure swings through simulated obstructive sleep apnea increase P-wave duration and Pd in healthy subjects and in patients with PAF. Our findings imply that intrathoracic pressure swings prolong the intra-atrial and inter-atrial conduction time and therefore may represent an independent trigger factor for the development for PAF.
authors.affiliation: Department of Pulmonology, University Hospital Zurich, Zurich, Switzerland.|Spital Zollikerberg, Zollikerberg, Switzerland.
authors.forename: Thomas
authors.identifier: http://orcid.org/0000-0002-9017-6143
authors.initials: T
authors.lastname: Gaisl
authors.affiliation: Department of Pulmonology, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Annette M
authors.initials: AM
authors.lastname: Wons
authors.affiliation: Department of Pulmonology, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Valentina
authors.initials: V
authors.lastname: Rossi
authors.affiliation: Department of Pulmonology, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Bratton
authors.affiliation: Department of Pulmonology, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Christian
authors.initials: C
authors.lastname: Schlatzer
authors.affiliation: Department of Pulmonology, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Esther I
authors.initials: EI
authors.lastname: Schwarz
authors.affiliation: Department of Pulmonology, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Camen
authors.affiliation: Department of Pulmonology, University Hospital Zurich, Zurich, Switzerland.|Centre for Integrative Human Physiology, University of Zurich, Zurich, Switzerland.|Centre for Interdisciplinary Sleep Research, University of Zurich, Zurich, Switzerland.
authors.forename: Malcolm
authors.initials: M
authors.lastname: Kohler
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000209:etiology* / Q000503:physiopathology*; D016022:Case-Control Studies; D004562:Electrocardiography / Q000706:statistics & numerical data; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D011312:Pressure; D012307:Risk Factors; D020182:Sleep Apnea, Central / Q000503:physiopathology; D020181:Sleep Apnea, Obstructive / Q000150:complications* / Q000503:physiopathology*; D055815:Young Adult