Transforming growth factor β1-mediated atrial fibrotic activity and the recovery of atrial mechanical contraction after surgical maze procedure

• Published in: International journal of cardiology 2013-04, Vol.164 (2), p.232-237
• Main Authors: Park, Seung-Jung, On, Young Keun, Kim, June Soo, Choi, Jin-Oh, Ju, Eun-Seon, Jeong, Dong Seop, Park, Pyo Won, Jeon, Eun-Seok
• Format: Article
• Language: English
• Subjects: Adult; Aged; Atrial fibrillation; Atrial Fibrillation - pathology; Atrial Fibrillation - physiopathology; Atrial Fibrillation - surgery; Atrial Function - physiology; Atrial mechanical contraction; Cardiovascular; Cryosurgery - methods; Electromechanical dissociation; Female; Fibrosis - metabolism; Fibrosis - pathology; Fibrosis - physiopathology; Follow-Up Studies; Humans; Male; Maze procedure; Middle Aged; Myocardial Contraction - physiology; Recovery of Function - physiology; Retrospective Studies; Transforming growth factor; Transforming Growth Factor beta1 - adverse effects; Transforming Growth Factor beta1 - physiology; Treatment Outcome
• ISSN: 0167-5273; 1874-1754
• DOI: 10.1016/j.ijcard.2013.01.066

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.