title: Sleep Apnea and Left Atrial Phasic Function in Heart Failure With Reduced Ejection Fraction.
abstract: The study aim was to determine whether phasic left atrial (LA) function of patients with heart failure with reduced ejection fraction differs between those with obstructive sleep apnea (OSA) and central sleep apnea (CSA).
  
  
  
  Participation in the Adaptive Servo Ventilation for Therapy of Sleep Apnea in Heart Failure (ADVENT-HF) trial requires 2-dimensional echocardiographic documentation of left ventricular ejection fraction ≤ 45% and a polysomnographic apnea hypopnea index (AHI) ≥ 15 events per hour. Of initial enrollees, we identified 132 patients in sinus rhythm (82 with predominantly OSA and 50 with CSA). To determine LA reservoir (expansion index; EI), conduit (passive emptying index; PEI), and booster function (active emptying index), we blindly quantified maximum and minimum LA volume and LA volume before atrial contraction.
  
  
  
  Each of EI (P = 0.004), PEI (P < 0.001), and active emptying index (P = 0.045) was less in participants with CSA compared with those with OSA, whereas average left ventricular ejection fraction and LA and left ventricular volumes were similar. Multivariable analysis identified an independent relationship between central AHI and LA EI (P = 0.040) and PEI (P = 0.005). In contrast, the obstructive AHI was unrelated to any LA phasic index, and slopes relating central AHI to EI and PEI differed significantly from corresponding relationships with obstructive AHI (P = 0.018; P = 0.006).
  
  
  
  In these ADVENT-HF patients with heart failure with reduced ejection fraction, all 3 components of LA phasic function (reservoir, conduit, and contractile) were significantly reduced in those with CSA compared with participants with OSA. The severity of CSA, but not OSA associated inversely and independently with LA reservoir and conduit function. Impaired LA phasic function might be consequent to or could exacerbate CSA.
authors.affiliation: University Health Network and Mount Sinai Hospital Department of Medicine, University of Toronto, Toronto, Ontario, Canada; Peter Munk Cardiac Centre, University Health Network, Toronto, Ontario, Canada.
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Haruki
authors.affiliation: University Health Network and Mount Sinai Hospital Department of Medicine, University of Toronto, Toronto, Ontario, Canada; Peter Munk Cardiac Centre, University Health Network, Toronto, Ontario, Canada.
authors.forename: Wendy
authors.initials: W
authors.lastname: Tsang
authors.affiliation: University Health Network and Mount Sinai Hospital Department of Medicine, University of Toronto, Toronto, Ontario, Canada; Peter Munk Cardiac Centre, University Health Network, Toronto, Ontario, Canada.
authors.forename: Paaladinesh
authors.initials: P
authors.lastname: Thavendiranathan
authors.affiliation: University Health Network and Mount Sinai Hospital Department of Medicine, University of Toronto, Toronto, Ontario, Canada; Peter Munk Cardiac Centre, University Health Network, Toronto, Ontario, Canada.
authors.forename: Anna
authors.initials: A
authors.lastname: Woo
authors.affiliation: University Health Network and Mount Sinai Hospital Department of Medicine, University of Toronto, Toronto, Ontario, Canada.
authors.forename: George
authors.initials: G
authors.lastname: Tomlinson
authors.affiliation: University Health Network and Mount Sinai Hospital Department of Medicine, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Alexander G
authors.initials: AG
authors.lastname: Logan
authors.affiliation: University Health Network and Mount Sinai Hospital Department of Medicine, University of Toronto, Toronto, Ontario, Canada; Sleep Research Laboratory of the University Health Network Toronto Rehabilitation Institute and Toronto General Hospital, Toronto, Ontario, Canada.
authors.forename: T Douglas
authors.initials: TD
authors.lastname: Bradley
authors.affiliation: University Health Network and Mount Sinai Hospital Department of Medicine, University of Toronto, Toronto, Ontario, Canada; Peter Munk Cardiac Centre, University Health Network, Toronto, Ontario, Canada. Electronic address: john.floras@utoronto.ca.
authors.forename: John S
authors.initials: JS
authors.lastname: Floras
mesh_terms: D000368:Aged; D016279:Atrial Function, Left / Q000502:physiology*; D002170:Canada; D004452:Echocardiography / Q000379:methods; D005260:Female; D006333:Heart Failure / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D017286:Polysomnography / Q000379:methods; D012121:Respiration, Artificial / Q000295:instrumentation / Q000379:methods; D012720:Severity of Illness Index; D020182:Sleep Apnea, Central / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology / Q000628:therapy; D020181:Sleep Apnea, Obstructive / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology / Q000628:therapy; D013223:Statistics as Topic; D013318:Stroke Volume