title: Biomarkers of collagen type I metabolism are related to B-type natriuretic peptide, left ventricular size, and diastolic function in heart failure.
abstract: OBJECTIVE
  Myocardial collagen metabolism can be assessed indirectly by circulating biomarkers. We aimed to examine associations between myocardial collagen type I synthesis and degradation, and echocardiographic, clinical, and B-type natriuretic peptide (BNP) findings in heart failure.
  
  
  METHODS
  We studied 57 women and 75 men 60 years or older with systolic heart failure (New York Heart Association II-IV and an ejection fraction ≤ 45%). Mean age was 75 years, blood pressure 134/80  mmHg, ejection fraction 34%, and median BNP 210  ng/l. Analyses of the carboxy-terminal propeptide of procollagen type I (PICP, biomarker of collagen type I synthesis) and the serum carboxy-terminal telopeptide of collagen type I (CITP, biomarker of collagen type I degradation) were measured. Extensive echocardiographic examinations were performed, including variables of dyssynchrony.
  
  
  RESULTS
  Increased collagen synthesis (PICP) was independently related to increased BNP levels (r = 0.24, P = 0.018). Furthermore, independent associations were found between PICP and left ventricular size, isovolumic relaxation time, and relative wall thickness. Increased collagen degradation (CITP) was independently related to increased BNP levels (r = 0.35, P < 0.001). Also, univariable, but not multivariable, associations were found between CITP and E/E' septal and QRS duration.
  
  
  CONCLUSIONS
  Biomarkers of collagen type I synthesis and degradation are independently related to BNP and to indices of left ventricular size and diastolic function in systolic heart failure. It is proposed that BNP may contribute to alterations in collagen type I metabolism in systolic heart failure.
authors.affiliation: aDivision of Cardiovascular Medicine, Department of Clinical Sciences, Danderyd Hospital, Karolinska Institutet bDepartment of Cardiology, Danderyd University Hospital, Stockholm, Sweden cDivision of Cardiovascular Sciences, Centre of Applied Medical Research dDepartment of Cardiology and Cardiac Surgery, School of Medicine, University of Navarra, Pamplona, Spain eErsta Hospital, Stockholm, Sweden.
authors.forename: Johan
authors.initials: J
authors.lastname: Löfsjögård
authors.forename: Thomas
authors.initials: T
authors.lastname: Kahan
authors.forename: Javier
authors.initials: J
authors.lastname: Díez
authors.forename: Begoña
authors.initials: B
authors.lastname: López
authors.forename: Arantxa
authors.initials: A
authors.lastname: González
authors.forename: Magnus
authors.initials: M
authors.lastname: Edner
authors.forename: Peter
authors.initials: P
authors.lastname: Henriksson
authors.forename: Märit
authors.initials: M
authors.lastname: Mejhert
authors.forename: Hans
authors.initials: H
authors.lastname: Persson
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D024042:Collagen Type I / Q000097:blood / Q000378:metabolism*; D003971:Diastole / Q000502:physiology; D005260:Female; D005355:Fibrosis; D006333:Heart Failure / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D006352:Heart Ventricles / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000378:metabolism / Q000473:pathology; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010455:Peptides / Q000097:blood; D012189:Retrospective Studies; D013318:Stroke Volume / Q000502:physiology; D014463:Ultrasonography
chemical_list: D015415:Biomarkers; D024042:Collagen Type I; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; D020097:Natriuretic Peptide, Brain