Postprandial Negatively Charged Very-Low-Density Lipoprotein ­Is a Novel Biomarker for Atrial Remodeling in Metabolic Syndrome

Abstract Background: Negatively charged very-low-density lipoprotein (VLDL-χ) in metabolic syndrome (MetS) patients exerts cytotoxic effects on endothelial cells and atrial myocytes. Atrial cardiomyopathy, manifested by atrial remodeling with a dilated diameter, contributes to atrial fibrillation pathogenesis and predicts atrial fibrillation development. The correlation of VLDL-χ with atrial remodeling is unknown. This study investigated the association between VLDL-χ and left atrial dilatation. Methods: We evaluated 87 MetS and 80 non-MetS individuals between 23 and 74 years old (50.6% men) without overt cardiovascular diseases. Blood samples were collected while fasting and postprandially (at 0.5, 1, 2, and 4 hours after a unified meal). VLDL was isolated by ultracentrifugation; the percentile concentration of VLDL-χ (%) was determined by ultra-performance liquid chromatography. The correlations of left atrial diameter (LAD) with variables including VLDL-χ, LDL-C, HDL-C, triglycerides, glucose, and blood pressure, were analyzed by multiple linear regression models. A hierarchical linear model was conducted to test the independencies of each variable’s correlation with LAD. Results: The mean LAD was 3.4 ± 0.5 cm in non-MetS subjects and 3.9 ± 0.5 cm in MetS patients (P< 0.01). None of the fasting lipid profiles were associated with LAD. VLDL-χ, BMI, waist circumference, hip circumference, and blood pressure were positively correlated with LAD (all P<0.05) after adjustment for age and sex. We observed significant interactions between VLDL-χ and blood pressure, waist circumference, and hip circumference. When adjusted for obesity- and blood pressure-related variables, 2-hour postprandial VLDL-χ (mean 1.30 ± 0.61%) showed a positive correlation with LAD in MetS patients. Each 1% VLDL-χ increase was estimated to increase LAD by 0.62 cm. Conclusion: Postprandial VLDL-χ is associated with atrial remodeling. VLDL-χ is a novel biomarker for atrial cardiomyopathy in MetS patients and may be a therapeutic target. Trial registration: ISRCTN 69295295. Registered 9 June 2020.