title: Atrial fibrillation and biomarkers of myocardial fibrosis in heart failure.
abstract: OBJECTIVE
  Alterations of collagen metabolism present in heart failure promote the fibrotic substrate for the development of atrial fibrillation (AF). Myocardial collagen I synthesis and degradation can be assessed indirectly by circulating biomarkers such as the carboxy terminal propeptide (PICP) and carboxy-terminal telopeptide (CITP), respectively.
  
  
  METHODS
  We examined myocardial collagen type-I metabolism in 143 patients with systolic heart failure (New York Heart Association Class 2-4) in relation to coexisting AF.
  
  
  RESULTS
  Mean age was 75 years, blood pressure 134/80 mm Hg, ejection fraction 34%, serum PICP 81 μg/L and CITP 8.3 μg/L, and median plasma brain natriuretic peptide 215 pg/L; 77 were in AF. PICP and CITP were related to left atrial diameter (r = 0.22, P = 0.013, and r = 0.26, P = 0.003) and CITP to pulmonary capillary wedge pressure and C-reactive protein (r = 0.19, P = 0.044, and r = 0.29, P = 0.003). A logistic regression suggested that PICP (odds ratio per 1 μg/L change 1.01, P = 0.012) and left ventricular end-diastolic volume (odds ratio per 1 mL change 0.98, P < 0.001) were independently associated with coexisting AF.
  
  
  CONCLUSIONS
  Collagen type-I metabolism is associated to left atrial size. Heart failure patients with coexisting AF exhibit more altered collagen type-I metabolism than patients in sinus rhythm. This might represent more severe atrial and ventricular fibrosis.
authors: Division of Cardiovascular Medicine, Department of Clinical Sciences, Danderyd Hospital, Karolinska Institutet , Stockholm , Sweden.
authors: Johan
authors: J
authors: Löfsjögård
authors: Hans
authors: H
authors: Persson
authors: Javier
authors: J
authors: Díez
authors: Begoña
authors: B
authors: López
authors: Arantxa
authors: A
authors: González
authors: Magnus
authors: M
authors: Edner
authors: Märit
authors: M
authors: Mejhert
authors: Thomas
authors: T
authors: Kahan
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000453:epidemiology*; D015415:Biomarkers; D002097:C-Reactive Protein / Q000032:analysis; D024042:Collagen Type I / Q000378:metabolism*; D005260:Female; D006333:Heart Failure / Q000453:epidemiology* / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D016015:Logistic Models; D008297:Male; D009206:Myocardium / Q000473:pathology*; D020097:Natriuretic Peptide, Brain / Q000097:blood; D011379:Prognosis
chemical_list: D015415:Biomarkers; D024042:Collagen Type I; D020097:Natriuretic Peptide, Brain; D002097:C-Reactive Protein
keywords: atrial fibrillation; collagen; echocardiography; heart failure; myocardial fibrosis