Abstract 17739: Gender Differences in Fibrotic Remodeling in Patients With Long-Standing Persistent Atrial Fibrillation and Mitral Valve Disease
Background: Gender-related differences have been reported in atrial fibrillation (AF); however, their effects on fibrotic remodeling of AF associated with mitral valve disease (MVD) have yet to be explored.
Methods and Results: Pulmonary vein sleeves (PVS) from 166 MVD patients with dilated left atria were examined. Among these, 101 patients (female, n=55; male, n=46) had long-standing persistent-AF (LSP-AF), while 65 (female, n=35; male, n=30) had no documented AF (NAF). Clinical characteristics showed no gender differences in left atrial enlargement ratio (LAER) between AF and NAF. Histological analysis revealed that female LSP-AF, rather than male, had a higher degree of fibrosis compared with NAF (female: 29.83%±11.22%vs 20.82% ±14.27%; male: 22.73% ± 10.42% vs 21.90% ± 10.20%). Moreover, the degree of fibrosis showed better predictive values for the presence of LSP-AF in female group (AUC = 0.7, P<0.01) than in male group (AUC = 0.508, P =0.902). Further analysis indicated gender differences in fibrotic remodeling of LSP-AF were due to inherent differential expression of the fibrosis-related mRNA genes (male, 6; female, 2) and proteins (male, 0; female, 5) as revealed by microarray and Western blot analyses. In addition, TGF-β2 pathway was found to be closely related to female fibrotic remodeling of LSP-AF.
Conclusion: While no gender-related differences were observed based on LAER, there was increased fibrotic remodeling in female subjects with LSP-AF, which was indicative of dysfunctional extracellular matrix (ECM) homeostasis. In summary, fibrotic remodeling plays a role in female LSP-AF, but not in male, suggesting a possible novel gender-based treatment and prevention strategy for LSP-AF.
Author Disclosures: H. Wang: None. Z. Li: None.
- © 2016 by American Heart Association, Inc.