Are fatty acids and fatty acid binding proteins novel biomarkers for cryoablation efficiency?

Purpose: Cryoablation is a recommended, modern and well-tolerated method of treating atrial fibrillation (AF). The study evaluates plasma biomarkers related to AF and the effectiveness of its treatment - cryoablation. Heart -and adipocyte-type fatty acid binding proteins (H-FABP and A-FABP, respectively) as well as fatty acids (FAs) were assessed in patients that underwent cryoballoon ablation (CBA) for AF.Patients and methods: Concentrations of plasma FABPs and FAs were measured in 33 AF patients on admission and 24 h after CBA (enzyme-linked immunoassay and gas liquid chromatography, respectively). The control group consisted of 20 volunteers.Results: We showed that plasma H-FABP and A-FABP concentrations were significantly higher in the patients with AF than in the control group (1135 pg/mL vs 836 pg/mL, and 34.29 ng/mL vs 15.14 ng/mL, respectively; p < 0.05). After CBA, H-FABP plasma concentration increased even further (1574 pg/mL vs 1135 pg/mL; p < 0.05) and FAs levels decreased concomitantly. AF recurred in 8 patients (24.25%) after 3 months and in 13 patients (39.4%) after 6 months. Initially higher concentration of oleic acid (680.24 +/- 189.768 vs 567.04 +/- 70.002; p < 0.05) correlated substantially with lower AF relapse rate in 6 months follow-up.Conclusions: The patients with AF showed increased concentration of H-FABP, whereas CBA triggered further elevation of H-FABP with a simultaneous decline in the total plasma FAs concentration. H-FABP and A-FABP could not be confirmed as new biomarkers of cryoablation efficiency, but this requires further investigation due to the limitations of the study.