title: Obstructive sleep apnea: effects of continuous positive airway pressure on cardiac remodeling as assessed by cardiac biomarkers, echocardiography, and cardiac MRI.
abstract: BACKGROUND
  Obstructive sleep apnea (OSA) is associated with an increased risk of cardiovascular morbidity and mortality. Although previous echocardiographic studies have demonstrated short-term improvement in cardiovascular remodeling in patients with OSA receiving continuous positive airway pressure (CPAP) therapy, a long-term study incorporating cardiac biomarkers, echocardiography, and cardiac MRI (CMR) has not been performed to date.
  
  
  METHODS
  A prospective study of 47 patients with OSA was performed between 2007 and 2010. Cardiac biomarkers, including C-reactive protein (CRP), N-terminal pro-B-type natriuretic peptide (NT-proBNP), and troponin T (TnT), were measured at baseline and serially over 1 year. All patients underwent baseline and serial transthoracic echocardiography (TTE) and CMR to assess cardiac remodeling.
  
  
  RESULTS
  Following 12 months of CPAP therapy, levels of CRP, NT-proBNP, and TnT did not change significantly from normal baseline values. As early as 3 months after initiation of CPAP, TTE revealed an improvement in right ventricular end-diastolic diameter, left atrial volume index, right atrial volume index, and degree of pulmonary hypertension, which continued to improve over 1 year of follow-up. Finally, left ventricular mass, as determined by CMR, decreased from 159 ± 12 g/m(2) to 141 ± 8 g/m(2) as early as 6 months into CPAP therapy and continued to improve until completion of the study at 1 year.
  
  
  CONCLUSIONS
  Both systolic and diastolic abnormalities in patients with OSA can be reversed as early as 3 months into CPAP therapy, with progressive improvement in cardiovascular remodeling over 1 year as assessed by both TTE and CMR.
authors.affiliation: Institute of Cardiovascular Sciences, St. Boniface General Hospital, University of Manitoba, Winnipeg, MB, Canada.
authors.forename: Jane
authors.initials: J
authors.lastname: Colish
authors.affiliation: Institute of Cardiovascular Sciences, St. Boniface General Hospital, University of Manitoba, Winnipeg, MB, Canada.
authors.forename: Jonathan R
authors.initials: JR
authors.lastname: Walker
authors.affiliation: Section of Cardiology, Department of Internal Medicine, University of Manitoba, Winnipeg, MB, Canada.
authors.forename: Nader
authors.initials: N
authors.lastname: Elmayergi
authors.affiliation: Section of Respiratory Medicine, Department of Internal Medicine, University of Manitoba, Winnipeg, MB, Canada.
authors.forename: Saleh
authors.initials: S
authors.lastname: Almutairi
authors.affiliation: Section of Respiratory Medicine, Department of Internal Medicine, University of Manitoba, Winnipeg, MB, Canada.
authors.forename: Fawaz
authors.initials: F
authors.lastname: Alharbi
authors.affiliation: Institute of Cardiovascular Sciences, St. Boniface General Hospital, University of Manitoba, Winnipeg, MB, Canada.
authors.forename: Matthew
authors.initials: M
authors.lastname: Lytwyn
authors.affiliation: Institute of Cardiovascular Sciences, St. Boniface General Hospital, University of Manitoba, Winnipeg, MB, Canada.
authors.forename: Andrew
authors.initials: A
authors.lastname: Francis
authors.affiliation: Institute of Cardiovascular Sciences, St. Boniface General Hospital, University of Manitoba, Winnipeg, MB, Canada.
authors.forename: Sheena
authors.initials: S
authors.lastname: Bohonis
authors.affiliation: Institute of Cardiovascular Sciences, St. Boniface General Hospital, University of Manitoba, Winnipeg, MB, Canada.
authors.forename: Matthew
authors.initials: M
authors.lastname: Zeglinski
authors.affiliation: Department of Radiology, University of Manitoba, Winnipeg, MB, Canada.
authors.forename: Iain D C
authors.initials: IDC
authors.lastname: Kirkpatrick
authors.affiliation: Section of Respiratory Medicine, Department of Internal Medicine, University of Manitoba, Winnipeg, MB, Canada.
authors.forename: Sat
authors.initials: S
authors.lastname: Sharma
authors.affiliation: Institute of Cardiovascular Sciences, St. Boniface General Hospital, University of Manitoba, Winnipeg, MB, Canada; Section of Cardiology, Department of Internal Medicine, University of Manitoba, Winnipeg, MB, Canada; Department of Radiology, University of Manitoba, Winnipeg, MB, Canada. Electronic address: djassal@sbgh.mb.ca.
authors.forename: Davinder S
authors.initials: DS
authors.lastname: Jassal
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D001794:Blood Pressure / Q000502:physiology; D002097:C-Reactive Protein / Q000378:metabolism; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000209:etiology; D045422:Continuous Positive Airway Pressure; D004452:Echocardiography; D005260:Female; D005500:Follow-Up Studies; D006321:Heart / Q000503:physiopathology; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology*; D020097:Natriuretic Peptide, Brain / Q000097:blood; D010446:Peptide Fragments / Q000097:blood; D011446:Prospective Studies; D012189:Retrospective Studies; D012307:Risk Factors; D020181:Sleep Apnea, Obstructive / Q000150:complications / Q000503:physiopathology* / Q000628:therapy*; D020107:Troponin T / Q000097:blood; D020257:Ventricular Remodeling / Q000502:physiology*
chemical_list: D015415:Biomarkers; D010446:Peptide Fragments; D020107:Troponin T; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain; D002097:C-Reactive Protein