Growth differentiation factor-15 (GDF-15), novel biomarker for assessing atrial fibrosis in patients with atrial fibrillation and rheumatic heart disease.

OBJECTIVE Growth differentiation factor-15 (GDF-15) has been identified as a strong biomarker of cardiovascular diseases; however, no evidence are available concerning the relationship of GDF-15 and atrial fibrosis in patients with atrial fibrillation (AF) and rheumatic heart disease (RHD). METHODS Twenty patients with rheumatic heart disease were divided into two groups, 10 cases with AF and 10 cases with sinus rhythm (SR). Clinical data and blood samples were collected; left atrial appendage was taken by the surgeon in the process of valve replacement. Masson stained sections and mRNA levels of cardiac fibrosis biomarkers were used to determine the level of cardiac fibrosis, the expression level of GDF-15 was evaluated via immunohistochemistry, enzyme-linked immunosorbent assay (ELISA) and real-time polymerase chain reaction (PCR). RESULTS Compared with SR group, more collagen deposited in the atrial tissue of AF group. The distribution of GDF-15 in the AF group was significantly higher than SR group (P<0.05). In addition, plasma GDF-15 level and mRNA level of GDF-15 in atrial tissue of AF showed the same trend as the result of immunohistochemistry. After linear correlation analysis, the expression level of GDF-15 was found to be positively related to the degree of cardiac fibrosis. CONCLUSION GDF-15 might involve in the development and maintenance of atrial fibrosis in patients with atrial fibrillation and rheumatic heart disease, and GDF-15 could be used as a novel biomarker to evaluate myocardial fibrosis in the future.