Impaired left ventricular mechanics in nonalcoholic fatty liver disease

Abstract

Nonalcoholic fatty liver disease (NAFLD) encompasses a disease spectrum ranging from simple steatosis to nonalcoholic steatohepatitis (NASH). We aimed to evaluate left ventricular (LV) systolic function using two-dimensional speckle-tracking echocardiography (2D-STE) in patients with NAFLD and to investigate whether any changes exist among the subgroups of NAFLD. We included 55 NAFLD patients and 21 healthy controls. The diagnosis of NAFLD was made on the basis of liver biopsy. After the patients were categorized into groups according to their histopathological analysis (simple steatosis, borderline NASH, and definitive NASH), all patients underwent echocardiography. In the 2D-STE analysis of the LV global longitudinal strain (G-LS), strain rate in systole (G-SRsys), strain rate in early diastole (G-SRearly), and strain rate in late diastole (G-SRlate) values were obtained. G-LS and G-SRsys values were lower in the NAFLD group. Although there was a significant difference in the G-LS between controls and simple steatosis, borderline NASH, and definitive NASH, no significant differences were found between NAFLD groups. To investigate whether impaired LV systolic dysfunction, determined using 2D-STE, is the consequence of NAFLD components, we included a subgroup. A total of 11 patients with NAFLD who were normotensive, nondiabetic, nonobese, and had a normal lipid profile and low homeostasis model assessment of insulin resistance (HOMA-IR) values were included. Echocardiographic abnormalities in systolic function were not different between this subgroup of NAFLD and healthy individuals. Patients with NAFLD and its subgroups have evidence of subclinical myocardial dysfunction in relation to the presence of insulin resistance. 2D-STE could not be used for differentiation of the NAFLD subgroups.