Serum Beta-2 Microglobulin: A Possible Biomarker for Atrial Fibrillation

BACKGROUND: Atrial fibrillation (AF) is the most common persistent arrhythmia that can cause complications (including stroke). Therefore, its diagnosis and treatment require increased attention. Although beta-2 microglobulin (β2-MG) is a novel marker of cardiovascular disease, its role in AF has not been evaluated. MATERIAL/METHODS: We conducted a case-control study with 61 patients who had normal heart rhythm (control group) and 60 patients with AF (research group). We analyzed the serum β2-MG levels in both groups and performed multivariate analysis to assess the correlation between β2-MG and left atrial remodeling. In addition, β2-MG levels were compared between the left atrial blood and peripheral venous blood of another set of 57 patients with AF, who underwent cryoballoon ablation. RESULTS: There were no statistically significant differences in the baseline characteristics (age, sex, history of hypertension, diabetes mellitus, previous stroke, coronary heart disease, and estimated glomerular filtration rate) of the control and research groups. The left atrial anteroposterior diameters (LAD) and left ventricular end-systolic diameters in the AF group were significantly larger compared to the control group (P<0.01). Serum β2-MG levels in patients with AF were significantly higher (P<0.01) and positively correlated with the LAD (B-coefficient 25.482, 95% CI 14.410~36.554, P<0.01), serum β2-MG levels in the left atrial blood were significantly higher than those in peripheral venous blood (P<0.01), and serum β2-MG levels were an independent predictor of AF. CONCLUSIONS: With the development of atrial fibrillation, the serum β2-MG levels increase and are closely related to the left atrial remodeling due to AF. Therefore, β2-MG can be an effective biomarker for predicting AF.