Association of obesity and hypertension with left ventricular geometry and function in children and adolescents

Abstract

Obesity, especially when complicated with hypertension, is associated with structural and functional cardiac changes. Recent studies have focused on the prognostic impact of the type of left ventricular (LV) geometric remodeling. This study looked at the prevalence and clinical correlates of LV geometric patterns and their relation to cardiac function in a sample of predominantly African-American (AA) youth. Echocardiographic data was collected on 213 obese (BMI of 36.53 ± 0.53 kg/m²) and 130 normal-weight subjects (BMI of 19.73 ± 0.21 kg/m²). The obese subjects had significantly higher LV mass index (LVMI; 49.6 ± 0.9 vs. 46.0 ± 1.0 g/m(2.7), P = 0.01), relative wall thickness (RWT; 0.45 ± 0.00 vs. 0.40 ± 0.00, P < 0.001), left atrial (LA) index (33.2 ± 0.7 vs. 23.5 ± 0.6 ml/m, P < 0.001), more abnormal diastolic function by tissue Doppler E/Ea septal (7.5 ± 0.14 vs. 6.5 ± 0.12 ms, P < 0.001), E/Ea lateral (5.7 ± 0.12 vs. 4.8 ± 0.1 ms, P < 0.001), myocardial performance index (MPI; 0.43 ± 0.00 vs. 0.38 ± 0.00, P < 0.001), and Doppler mitral EA ratio (2.0 ± 0.04 vs. 2.4 ± 0.07, P < 0.001) but similar systolic function. Concentric remodeling (CR) was the most prevalent pattern noted in the obese group and concentric hypertrophy (CH) in the obese and hypertensive group. Obesity, hypertension, and CH were independent predictor of diastolic dysfunction. Systolic (SBP) and diastolic blood pressures (DBP) were the prime mediators for CH whereas obesity and diastolic blood pressure were predictors of CR. No significant association was observed between the geometric patterns and systolic function. Tracking LV hypertrophy (LVH) status and geometric adaptations in obesity may be prognostic tools for assessing cardiac risk and therapeutic end points with weight loss.