ABSTRACT
Objective: To investigate the correlation between atrial tissue aldosterone level and atrial extracellular matrix remodeling in patients with atrial fibrillation and to evaluate the effects of aldosterone on the progress of atrial structural remodeling. Methods: Twenty-five patients with rheumatic heart valve disease (12 with sinus rhythm, 13 with chronic atrial fibrillation for ≥6 months) were included in the present study. The right and left atrial lateral wall tissue samples (12 right and 7 left atrial samples in patients with sinus rhythm; 13 right and 8 left atrial samples in patients with atrial fibrillation) were obtained during mitral/aortic valve replacement operation. Radioimmunoassay was used to determine aldosterone level in local atria. Type I or III collagen volume fraction (CVF-I or CVF-III) and total collagen volume fraction (CVF) were analyzed by immunohistochemistry and VG staining, respectively. Results: The left atrial diameters increased markedly in the atrial fibrillation group as compared to those in the sinus rhythm group (P<0.01). Aldosterone level, CVF-I, CVF-I/CVF-III ratio, and total CVF in atrial fibrillation group were also increased significantly than those of sinus rhythm group (P<0.01), whereas CVF-III remained compatible in the 2 groups. Aldosterone level, CVF-I, CVF-I/CVF-III ratio, and total CVF were similar between the left atria and right atria in both groups. It was found that CVF-I was positively correlated with the left atrial dimension (r=0.856, P<0.001), CVF was positively correlated with left atrial dimension(r=0.845, P<0.01), and CVF-I/ CVF-III ratio was positively correlated with atrial fibrillation duration (r=0.766, P<0.01). Aldosterone level in local atria was also positively correlated with left atrial dimension (r=0.814, P < 0.001) and CVF (r = 0.885, P < 0.001). Conclusion: Local atria aldosterone level may promote the process of atrial structural remodeling in patients with atrial fibrillation and may also participate in the development and persistence of atrial fibrillation.
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the mRNA and protein expressions of 11beta-Hydroxysteroid dehydrogenase type 2 (11betaHSD2) in patients with atrial fibrillation.</p><p><b>METHODS</b>Right and left atrial lateral wall tissue samples were obtained during mitral/aortic valve replacement operation from 25 patients with rheumatic heart valve disease (12 in sinus rhythm and 13 in chronic atrial fibrillation). Realtime quantitative PCR and Western blot were used to determine the mRNA and protein expressions of 11betaHSD2 in atria specimens. The distribution of 11betaHSD2 in human atrial tissue was analyzed by specific immunohistochemical staining. Echocardiography examination was performed before operation.</p><p><b>RESULTS</b>The left atrial diameters were significantly higher in the atrial fibrillation group as compared to sinus rhythm group (P < 0.01). Similarly, mRNA expression of 11betaHSD2 (0.86 +/- 0.14 vs 0.33 +/- 0.12 in right atria, 0.95 +/- 0.15 vs 0.37 +/- 0.10 in left atria, all P < 0.01) and protein expression of 11betaHSD2 (1.18 +/- 0.64 vs 0.71 +/- 0.21 in right atria, P < 0.01; and 1.36 +/- 0.58 vs 0.85 +/- 0.15 in left atria, P < 0.05) were also significantly upregulated in atrial fibrillation groups than those in sinus rhythm groups. The mRNA and protein expressions of 11betaHSD2 were similar between left atria and right atria both in fibrillation and sinus groups (all P > 0.05). The special immunohistochemical staining demonstrated that 11betaHSD2 was abundant in the human atrial myocardium and located mainly in the cytoplasm.</p><p><b>CONCLUSION</b>These findings suggested that upregulated 11betaHSD2 might be associated to the development and persistence of atrial fibrillation.</p>
Subject(s)
Adult , Female , Humans , Male , Middle Aged , 11-beta-Hydroxysteroid Dehydrogenase Type 2 , Metabolism , Atrial Fibrillation , Metabolism , Heart Atria , Metabolism , Myocardium , Metabolism , RNA, Messenger , Genetics , Rheumatic Heart Disease , MetabolismABSTRACT
<p><b>OBJECTIVE</b>To evaluate the effect and possibility of surgical ablation of the pulmonary vein orifices under direct vision with transballoon ultrasound ablation catheter for patients with permanent atrial fibrillation and rheumatic valve disease.</p><p><b>METHODS</b>21 consecutive patients with rheumatic valve disease and permanent atrial fibrillation undergoing mitral valve replacement surgery were enrolled for this study from December 2002 to September 2003. All the cases were divided into 2 groups by whether or not receiving an additive pulmonary vein ablation procedure. The test group [6 male, 5 female, aged (51.55 +/- 7.83) years, atrial fibrillation duration (5.50 +/- 5.40) years, left atrial diameter (7.27 +/- 1.39) cm, LVEF (53.95 +/- 4.54)% and NYHA class II - IV] undertook a surgical isolation of the pulmonary vein orifices by using a transballoon ultrasound ablation catheter addition to routine mitral valve replacement. The control group [3 male, 7 female, aged (53.30 +/- 7.86) years, atrial fibrillation duration (4.50 +/- 3.47) years, left atrial diameter (6.74 +/- 0.62) cm, LVEF (56.91 +/- 3.78)% and NYHA class II - IV] received the valve replacement surgery alone.</p><p><b>RESULTS</b>There were not any complications in both groups. With an electrical cardioversion 3 months after the surgery, 73% patients in the ultrasound ablation group were free from AF over 1 year while only 10% patients in control group (P=0.003). During an average follow-up duration of (45.92 +/- 4.61) months, 63.6% were in sinus rhythm in ultrasound ablation group while none in the control group. Left atrial volume decreased significantly at 1 year after surgery compared to that at 3 months after surgery in the test group [(97.83 +/- 32.39) cm(3) vs. (150.78 +/- 52.32) cm(3), P<0.05], and the end systolic diameter (LAESD) and end diastolic diameter (LAEDD) also decreased [(4.12 +/- 0.39) cm vs. (5.09 +/- 0.98) cm, P<0.05, respectively], while there were no apparently changes in the control group.</p><p><b>CONCLUSIONS</b>Ablation of the orifices of the pulmonary veins under direct vision with transballoon ultrasound ablation catheter during mitral valve surgery seems effective to maintain sinus rhythm after electrical cardioversion and could be performed safely. The function of left atrial and cardiac output improved during long term follow-up of 46 months.</p>
Subject(s)
Female , Humans , Male , Middle Aged , Atrial Fibrillation , Therapeutics , Catheter Ablation , Methods , Catheterization , Heart Valve Diseases , Therapeutics , Pulmonary Veins , Rheumatic Heart Disease , Therapeutics , Ultrasonic TherapyABSTRACT
<p><b>OBJECTIVE</b>To investigate the mRNA and protein expression of mineralocorticoid receptor (MR) in patients with atrial fibrillation.</p><p><b>METHODS</b>Twenty-five patients with rheumatic heart valve disease, 12 in sinus rhythm and 13 in chronic atrial fibrillation (>or= 6 months), underwent transthoracic echocardiography and right and left atrial lateral wall tissue samples were obtained from these patients during mitral/aortic valve replacement operation. Realtime quantitative PCR and Western blot were used to determine the mRNA and protein expression of MR in atria specimens. The distribution of MR in human atria was analyzed by specific immunohistochemical staining.</p><p><b>RESULTS</b>The left atrial diameters increased markedly in atrial fibrillation group compared with that in sinus rhythm group (P<0.01). And the results showed that the level of mRNA and protein of MR were increased significantly in atrial fibrillation group compared with those in sinus rhythm group (P<0.01 or 0.05), whereas the expression of mRNA and protein of MR were found to be no difference between left atria and right atria both in fibrillation and sinus groups (all P>0.05). The special immunohistochemical staining demonstrated that MR was abundant in the human atrial myocardium and MRs were located mainly in the cytoplasm of atrial cells, which were more evident in atrial fibrillation group than those in sinus rhythm group.</p><p><b>CONCLUSION</b>These findings suggested that MRs were upregulated in atrial fibrillation and aldosterone antagonists may be effective in treating atrial fibrillation.</p>