Rheumatic valvular surgery and concomitant radiofrequency Maze procedure: TGF-β1 mRNA expression predicting the efficacy

Abstract

To investigate the relationship of the transforming growth factor beta1 (TGF-β1) mRNA expression in atrial myocardium and the effectiveness of radiofrequency Maze procedure in patients with rheumatic valvular disease (RHD) and permanent atrial fibrillation (AF). Between January 2008 and September 2008, 40 patients with RHD and AF underwent a radiofrequency Maze procedure with concomitant valvular surgery. The patients were assigned to normal sinus rhythm (SR) group (group A) and persistence AF group (group B) according to the results of the 6-month follow-up. Another 10 patients with SR and RHD undergone valvular surgery alone were assigned to control group (group C). Left atrial appendage were obtained in all patients. Expressions of TGF-β1 mRNA were detected by semiquantitative RT-PCR technique. CVF-I and CVF-III were observed by sirius red staining. At 6-month follow-up, there were 28 patients in group A and 12 in group B. Patients in group A and group B had higher mRNA expressions of TGF-β1, CVF-I and CVF-I/CVF-III compared with group C (P < 0.05). Also, the group B had higher mRNA expressions of TGF-β1, CVF-I and CVF-I/CVF-III than group A (P < 0.05). The patients who had return of functional atrial contraction in group A had lower mRNA expression than the non-return patients (39 ± 12 vs. 60 ± 12, P < 0.05). The TGF-β1 mRNA expression had a correlation with both the contents of CVF-I and left atrial diameter (r = 0.786, P < 0.05; r = 0.858, P < 0.05). Multiple logistic regression analysis revealed that the risk factors which independently associated with the postoperative persistence of atrial fibrillation at 6-month follow-up includes mRNA expression levels of TGF-β1 (OR = 1.13, 95%CI 1.05 - 1.18, P = 0.031), CVF-I (OR = 1.07, 95%CI 1.00 - 1.13, P = 0.037) and lett atrial diameter (OR = 2.23, 95%CI 1.08 - 4.59, P = 0.042). The atrial TGF-β1 mRNA expression level could predict the persistence of AF and the return of the functional atrial contraction at 6-month follow-up in patients who underwent rheumatic valvular surgery and concomitant radiofrequency Maze procedure.