Abstract 34: Assessment Of Early Myocardial Deformation Changes In Dyslipidemic Children By Three-dimensional Speckle Tracking Imaging

Abstract

Background. Dyslipidemia is considered a strong risk factor for premature atherosclerotic cardiovascular disease and increased morbidity and mortality and may have an adverse effect on left ventricular (LV) performance. Three-dimensional speckle tracking imaging (3D-STI) provides information regarding different echocardiographic parameters of LV myocardial deformation. Purpose. Our aim was to assess the presence of early myocardial deformation abnormalities in nonselected dyslipidemic children free from other cardiovascular risk factors. Methods. Twenty-four consecutive nonselected hypercholesterolemic children (TC above the 95th percentile for age and gender, mean age 11.3 ± 2.16 years) and 24 healthy age-matched children were enrolled. None of them had any other cardiovascular risk factors. Obesity (body mass index >75th percentile for age and gender) as well as other diseases were excluded. Every subject underwent 2D- and 3D-STI. Volumes were measured from 3D datasets. Global longitudinal strain (GLS), global circumferential strain (GCS), global area strain (GAS), and global radial strain (GRS) were computed at end-systole. GAS was calculated as the percentage variation in the surface area defined by the longitudinal and circumferential strain vectors. Data analysis was performed offline (EchoPAC BT11, 4D Auto LVQ, GE). Results. Mean percentage intraobserver variability was 7% for GLS, 9% for GCS, 6% for GAS, and 11% for GRS. Comparison between 2D and 3D GLS showed high correspondence (r = 0.89, y = 1.13x - 0.78). The mean time of analysis was of 149 ± 27 sec for 3D analysis, which was 17% less than for 2D analysis (p<0.05). The following strain values were obtained in hyperlipidemic patients compared to controls: 3D GLS (-14.7±2.5% vs -16.8±2.7%, p <0.005), 3D GCS (-28.1±3.6% vs -29.6±4.2%, p <0.01), 3D GRS (29.6±9.2% vs 30.2±9.7%, p =NS), and 3D GAS (-39.8±3.4% vs -43.2±3.2%, p <0.001). On multivariate logistic regression analysis, the strongest relationship with dyslipidemia was found for LV GAS (β- coefficient= 0.74, r 2 = 0.61, p= 0.002). Conclusions. Dyslipidemia is associated with myocardial deformation changes independently from any other cardiovascular risk factor or any structural cardiac abnormalities.