The role of galectin-3 in patients with permanent and paroxysmal Atrial Fibrillation and echocardiographic parameters of left atrial fibrosis

Abstract Background: Atrial fibrillation (AF) is the most common type of sustained arrhythmia in clinical practice. Biochemical markers and imaging tests have been used with the aim of stratifying the risk and detecting atrial fibrosis. Speckle-tracking echocardiography (STE) is used for the detection of atrial fibrosis and Gal-3 provides an important prognostic value. The objective of the study was to assess the association between atrial fibrosis markers and serum levels, genetic polymorphisms and genic expression of galectin-3. Methods: Two hundred and six patients with permanent AF and 70 patients with paroxysmal AF were included in the study. Real time PCR (TaqMan) system was used to study SNPs rs4652 and 4644 of the gene LGALS3 . Serum levels of Gal-3 were determined by ELISA and STE was performed to assess fibrosis. Results: Mean age of individuals with permanent AF was 66.56±12 years. As for the echocardiography results, those patients showed an increase in the following parameters: left atrial diameter (LAD) (p=0.007), LA volume (p=0.02) and volume indexed to the body surface area (p=0.04). And a decrease in values of peak atrial longitudinal strain (PALS) (p=0.002) when compared to the same parameters from the paroxysmal AF group of patients. There was a correlation between serum levels of Gal-3 and PALS in the group of patients with permanent AF; the lower the levels of gal-3, the lower the LA strain (r=0.24; p=0.01). Conclusions: Echocardiographic findings showed association with the groups, and with serum levels of Gal-3 in patients with permanent AF. The distribution of allelic and genotypic frequencies, and of the haplotypes of polymorphism LGALS3 rs4652 and rs4644 did not present statistical variation, which suggests that those SNPs are not associated with the AF clinical forms (permanent and paroxysmal).