Increased levels of inflammatory and extracellular matrix turnover biomarkers persist despite reverse atrial structural remodeling during the first year after atrial fibrillation ablation.

PURPOSE: Left atrial (LA) remodeling associated with atrial fibrillation (AF) is known to be related to inflammation and collagen turnover. We investigated the changes in the biomarkers of inflammation and collagen turnover in relation to LA reverse remodeling during the 1st year after AF ablation.
METHODS: Biomarkers of inflammation [high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6)] and collagen turnover [matrix metalloproteinase-2 (MMP-2), tissue inhibitor of MMP-2 (TIMP-2), transforming growth factor beta 1 (TGF-β1)], as well as asymmetric dimethylarginine (ADMA) and adiponectin levels were measured, and echocardiographic measurements were obtained before and 3, 6, and 12 months after ablation in 60 AF patients (49 males; age, 57.6 ± 10.9 years).
RESULTS: During a 12.1 (11.5-12.9)-month follow-up period, AF recurred in 29 patients (48 %). Neither the LA volume (LAV) nor the left ventricular ejection fraction (LVEF) changed significantly during the 1st year in this group, but the LAV decreased significantly, and the LVEF increased significantly in the nonrecurrence group. The hs-CRP and IL-6 decreased after ablation but returned near to baseline levels in both groups by 12 months. The MMP-2 remained increased during the 1st year in both groups, whereas the TIMP-2 increased markedly in the nonrecurrence group but did not change substantially in the recurrence group. The TGF-β1 increased in both groups, but the change was less pronounced in the recurrence group. The ADMA and adiponectin levels did not change substantially in either group.
CONCLUSIONS: Despite reverse remodeling, the inflammation and collagen turnover biomarker levels are quite progressive during the 1st year after ablation and may explain the late AF recurrence.