Non-Alcoholic Fatty Liver Disease Is Associated with Impairment of Ejection Fraction Among Individuals with Obesity Undergoing Bariatric Surgery: Results of a Cross-Sectional Study

Abstract

Background: The relationship between non-alcoholic fatty liver disease (NAFLD) and myocardial function seems to be more than just the effect of mutual metabolic risk factors. Objective: To determine whether there is a significant association between NAFLD assessed by means of liver biopsy and left ventricular function expressed by the estimated ejection fraction among individuals with obesity. Methods: This is a cross-sectional study which enrolled individuals who consecutively underwent bariatric surgery. NAFLD was assessed by means of liver biopsies which were systematically collected during the procedures. The estimated ejection fraction was obtained by means of transthoracic echocardiograms. The main outcome evaluated was a possible association between NAFLD features and ejection fraction. The results of liver biopsies and the respective degrees of severity of each NAFLD feature were also correlated with the ejection fraction and main anthropometric, biochemical, and clinical variables. Results: Of 112 individuals, 86.6% were female and the mean age was 38.5 ± 9.3 years. It was observed that the average estimated ejection fraction (EEF) was significantly lower among individuals with liver fibrosis (67.6 ± 5.5% vs. 70.8 ± 4.9%, p = 0.008). After adjustment for confounding variables in a multivariate model, the degree of liver fibrosis was independently associated with the EEF (R = − 0.3, p = 0.02). Conclusion: Among individuals with morbid obesity, the findings of this study are suggestive that liver fibrosis confirmed by histopathological examination is associated with a slight impairment of left ventricular function. Further studies are needed to confirm this association.