Left ventricular function by echocardiography, tissue Doppler imaging, and carotid intima-media thickness in obese adolescents with nonalcoholic fatty liver disease

Abstract

The aims of this study were to evaluate left ventricular (LV) systolic and diastolic function in obese adolescents with nonalcoholic fatty liver disease (NAFLD) using conventional echocardiography and pulsed-wave tissue Doppler imaging and to investigate the relations between LV function and carotid intima-media thickness (CIMT). LV remodeling, tissue Doppler-derived LV velocities, and cardiovascular risk profiles in obese adolescents with NAFLD were also studied. One hundred eighty obese adolescents and 68 healthy controls were enrolled in the study. LV end-diastolic and end-systolic and left atrial diameters and LV mass were higher in the 2 obese groups compared with controls. By pulsed-wave Doppler echocardiography and pulsed-wave tissue Doppler imaging, the NAFLD group had normal LV systolic function, impaired diastolic function, and altered global systolic and diastolic myocardial performance. In patients with NAFLD, LV mass was positively correlated with homeostasis model assessment of insulin resistance and serum alanine aminotransferase. CIMT was positively correlated with homeostasis model assessment of insulin resistance, alanine aminotransferase, and LV mass. By multiple stepwise regression analysis, alanine aminotransferase (β = 0.124, p = 0.026), homeostasis model assessment of insulin resistance (β = 0.243, p = 0.0001), LV mass (β = 0.874, p = 0.0001) were independent parameters associated with increased CIMT. In conclusion, insulin resistance has a significant independent impact on CIMT and LV remodeling in the absence of diabetes in patients with NAFLD. Pulsed-wave tissue Doppler imaging is suggested to detect LV dysfunction at an earlier stage in obese adolescents with NAFLD for careful monitoring of cardiovascular risk.