title: Control theory prediction of resolved Cheyne-Stokes respiration in heart failure.
abstract: Cheyne-Stokes respiration (CSR) foretells deleterious outcomes in patients with heart failure. Currently, the size of therapeutic intervention is not guided by the patient's underlying pathophysiology. In theory, the intervention needed to resolve CSR, as a control system instability (loop gain >1), can be predicted knowing the baseline loop gain and how much it falls with therapy.In 12 patients with heart failure, we administered an inspiratory carbon dioxide fraction of 1-3% during CSR (n=95 interventions) as a means to reduce loop gain. We estimated the loop gain on therapy (LGtherapy), using the baseline loop gain (using hyperpnoea length/cycle length) and its expected reduction (18% per 1% inspired carbon dioxide), and tested the specific hypothesis that LGtherapypredicts CSR persistence (LGtherapy>1) versus resolution (LGtherapy<1).As predicted, when LGtherapy>1.0, CSR continued during therapy in 23 out of 25 (92%) trials. A borderline loop gain zone (0.8<LGtherapy<1) yielded an unpredictable outcome, while LGtherapy<0.8 consistently yielded CSR resolution (37 out of 37 trials). A threshold of LGtherapy=0.9 determined outcome in 76 out of 95 (80%) trials.We establish proof-of-concept that control theory provides predictive insight into CSR resolution in heart failure. Thus, we now have a means to calculate the size of interventions needed to ameliorate CSR on a patient-by-patient basis.
authors: General Respiratory and Sleep Medicine, Dept of Allergy Immunology and Respiratory Medicine, The Alfred, Melbourne, Australia sasands@partners.org.|Central Clinical School, Monash University, Melbourne, Australia.|Sleep Disordered Breathing Laboratory, Division of Sleep and Circadian Disorders, Depts of Medicine and Neurology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.|The Ritchie Centre, Hudson Institute of Medical Research, Monash University, Melbourne, Australia.
authors: Scott A
authors: SA
authors: Sands
authors: Sleep Disordered Breathing Laboratory, Division of Sleep and Circadian Disorders, Depts of Medicine and Neurology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.|Sleep and Circadian Medicine Laboratory, Dept of Physiology, Monash University, Melbourne, Australia.|School of Psychological Sciences and Monash Institute of Cognitive and Clinical Neurosciences, Monash University, Melbourne, Australia.
authors: Bradley A
authors: BA
authors: Edwards
authors: General Respiratory and Sleep Medicine, Dept of Allergy Immunology and Respiratory Medicine, The Alfred, Melbourne, Australia.|Central Clinical School, Monash University, Melbourne, Australia.
authors: Kirk
authors: K
authors: Kee
authors: General Respiratory and Sleep Medicine, Dept of Allergy Immunology and Respiratory Medicine, The Alfred, Melbourne, Australia.
authors: Christopher
authors: C
authors: Stuart-Andrews
authors: The Ritchie Centre, Hudson Institute of Medical Research, Monash University, Melbourne, Australia.
authors: Elizabeth M
authors: EM
authors: Skuza
authors: General Respiratory and Sleep Medicine, Dept of Allergy Immunology and Respiratory Medicine, The Alfred, Melbourne, Australia.
authors: Teanau
authors: T
authors: Roebuck
authors: Monash Lung and Sleep, Monash Medical Centre, Melbourne, Australia.
authors: Anthony
authors: A
authors: Turton
authors: Monash Lung and Sleep, Monash Medical Centre, Melbourne, Australia.|School of Clinical Sciences, Monash University, Melbourne, Australia.
authors: Garun S
authors: GS
authors: Hamilton
authors: General Respiratory and Sleep Medicine, Dept of Allergy Immunology and Respiratory Medicine, The Alfred, Melbourne, Australia.|Central Clinical School, Monash University, Melbourne, Australia.
authors: Matthew T
authors: MT
authors: Naughton
authors: The Ritchie Centre, Hudson Institute of Medical Research, Monash University, Melbourne, Australia.
authors: Philip J
authors: PJ
authors: Berger
mesh_terms: D000368:Aged; D002245:Carbon Dioxide; D002639:Cheyne-Stokes Respiration / Q000503:physiopathology*; D006333:Heart Failure / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010102:Oxygen Inhalation Therapy / Q000379:methods*; D017286:Polysomnography; D012119:Respiration; D012890:Sleep; D016896:Treatment Outcome
chemical_list: D002245:Carbon Dioxide