title: Transforming growth factor β1-mediated atrial fibrotic activity and the recovery of atrial mechanical contraction after surgical maze procedure.
abstract: BACKGROUND
  The maze procedure for atrial fibrillation (AF) is effective in restoring sinus rhythm; however, a significant proportion of patients failed to recover atrial mechanical contraction (AMC). We hypothesized that preoperative atrial fibrotic activity would be related to the AMC recovery.
  
  
  METHODS
  In atrial tissues of 128 consecutive patients who underwent mitral valve and combined maze surgery using cryoablation for persistent AF, preoperative mRNA levels of various biomarkers were measured including transforming growth factor-β1 (TGF-β1), atrial natriuretic peptide, brain natriuretic peptide (BNP), C-reactive protein, connective tissue growth factor, matrix metalloproteinase, N-terminal prohormone BNP, and tissue inhibitor of metalloproteinase. Presence of AMC was assessed using Doppler echocardiographic measurement of the transmitral A-wave velocity.
  
  
  RESULTS
  At 1-year follow-up, patients without AMC (n=62) showed higher preoperative TGF-β1 mRNA expression (0.42 versus 0.28, P=0.01) than those with AMC (n=66). There was no significant difference between the two groups regarding the other biomarkers. Recovery rate of AMC and the increment of A-wave velocity were reduced with the increase of preoperative TGF-β1 mRNA level. Multiple logistic regression analysis revealed that TGF-β1 mRNA levels were independently associated with the absence of AMC (odds ratio 7.47, 95% CI 1.63 to 34.4, P=0.01).
  
  
  CONCLUSIONS
  TGF-β1-mediated atrial fibrotic activity might exert a detrimental effect on the reversibility of atrial mechanical contraction after the maze and combined mitral valve surgery for long-standing persistent AF. Earlier surgical intervention might be needed to preserve atrial mechanical function.
authors: Department of Internal Medicine, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors: Seung-Jung
authors: SJ
authors: Park
authors: Young Keun
authors: YK
authors: On
authors: June Soo
authors: JS
authors: Kim
authors: Jin-Oh
authors: JO
authors: Choi
authors: Eun-Seon
authors: ES
authors: Ju
authors: Dong Seop
authors: DS
authors: Jeong
authors: Pyo Won
authors: PW
authors: Park
authors: Eun-Seok
authors: ES
authors: Jeon
mesh_terms: D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery*; D016275:Atrial Function / Q000502:physiology*; D003452:Cryosurgery / Q000379:methods*; D005260:Female; D005355:Fibrosis / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000502:physiology*; D020127:Recovery of Function / Q000502:physiology*; D012189:Retrospective Studies; D053773:Transforming Growth Factor beta1 / Q000009:adverse effects / Q000502:physiology*; D016896:Treatment Outcome
chemical_list: D053773:Transforming Growth Factor beta1