Epicardial fat may influence upon remodeling of the heart which can be the cause of atrial fibrillation (AFib). Study objective - to evaluate the epicardial fat thickness (EFT) and to reveal the possible relationship of this parameter with galectin-3 (Gal-3) as markers of fibrosis in patients with AFib and metabolic syndrome (MetS).
100 patients 35–65 y.o. with MetS (IDF,2005) including 50 patients with paroxysmal (n = 28) and persistent (n = 22) AFib were examined. The control group was 50 persons without metabolic disorders. The examination includes: medical history, echocardiography, serum levels of Gal-3 (Enzyme immunoassay). The EFT was measured with echocardiography. 25 patients with paroxysmal AFib were treated with radiofrequency ablation with vein isolation. Ablation procedure was performed with the system of electroanatomical mapping CARTO 3 (Biosense Webster Inc, USA) and contact force monitoring catheter (SmartTouch). After ablation, we analyzed the clinical data and the effectiveness of therapy during follow-up (12 months).
The epicardial fat thickness was more than 2 fold greater in the MetS compared with the control group (4,7 ± 1,3 and 2,4 ± 0,9 mm;p < 0,001). Gal-3 in patients with MetS with AFib was more than 2 fold higher than in healthy control (0,72 [0,44;1,36] and 0,32 [0,28;0,42] ng/ml;p < 0,001). Correlation analysis was showed a strong positive correlation between EFT and volume of the left atrium (r = 0,61;p < 0,001). In patients with MetS and AFib with EFT more than 3,5 mm the risk of AFib is 3,9 folds higher (OR = 3,92,95%CI 1,98–7,78,p < 0,001). Positive correlation between EFT and Gal-3 was revealed (r = 0,61;p < 0,001). After prospective study, we registered recurrent paroxysms of AFib in 29 patients. EFT was greater in patients with recurrent paroxysms of AFib than in patients without paroxysms of AFib (4,5 ± 1,5 and 2,8 ± 1,5 mm,p = 0,001). The multivariate regression analysis demonstrated that EFT is an independent predictor of non-effective of radiofrequency ablation therapy of AFib (OR = 1,47,95%CI 1,02–2,04,p = 0,014).
Greater thickness of epicardial fat is associated with higher levels of galectin-3 and with higher risk of non-effectiveness of radiofrequency ablation. Left atrium fibrosis degree correlates with epicardial fat thickness and it can influence on remodeling of the heart. Greater thickness of epicardial fat.
1Pavlov First Saint Petersburg State Medical University, Saint-Petersburg, Russia
2Almazov National Medical Research Centre, Saint-Petersburg, Russia