Abstract 18228: Impaired Diastolic and Dystolic Deft Ventricular Function in Children With Obesity Assessed by Tissue Doppler Imaging
The increasing prevalence of obesity in childhood appears to precede the development of cardiovascular diseases. Tissue Doppler Imaging enables detection of impaired myocardial performance in patients with hypertension, diabetes and ischemic heart disease. In this context, less is known about left-ventricular performance in children with obesity. Therefore aim of this ongoing study is to evaluate whether obese children are already characterized by subclinical myocardial dysfunction.
Methods: Twenty one obese (O) (Age 13±2, BMI 30±4) and 33 lean control children (L) (Age 14±3, BMI 19±3) were examined with colour TDI, two-dimensional and M-Mode echocardiography. LA size, LV wall thickness and dimensions were measured and LV-Mass (LVMI) calculated. All measurements were indexed by dividing height raised to a power of 2.7. Mitral inflow (E/A ratio) was assessed by pulsed-wave Doppler. Peak systolic (s′) and early diastolic (e′) myocardial velocities and basoseptal strain (SI) were obtained from colour TDI loops.
Results: In comparison to L, O show higher LVMI (28.5±6.0 vs. 39.84±8.5 g/m2.7, p<0.01), higher end-diastolic volume (21.9±4.9 vs. 28.0±5.3 ml/m2.7, p<0.01) and bigger LA (7.9±2.1 vs. 9.2±1.4 mm/m2.7, p<0.05). Both L and O have a normal LV-EF (63.5±4.7 vs. 61.7±4.8). Despite identical LV-EF, s′ (7.1±1.2 vs. 6.4±1.1 cm/s, p=0.03) and SI (22.3±4.4 vs. 17.7±4.8 %, p<0.01) are reduced in O indicating an impairment of myocardial performance. In comparison to L, O are characterized by an impaired diastolic LV function as assessed by a reduced E/A (2.3±0.6 vs. 1.9±0.4, p<0.01). E′ at the lateral and septal mitral annulus is reduced in obese children (e′ lat: 20.1±2.6 vs. 18.0±2.5 cm/s, p<0.01; e′ sep: 15.1±1.7 vs. 12.8±1.8 cm/s, p<0.01). In contrast, E/e′ is elevated in O in comparison to L (E/e′ lat: 4.9±0.9 vs. 5.7±1.1, p<0.01; E/e′ sep: 6.5±1.1 vs. 8.0±1.5, p<0.01).
Conclusion: Already in children and adolescents, obesity is associated with reduced systolic and diastolic myocardial performance in comparison to lean control subjects elucidated by tissue Doppler imaging. Since TDI-derived parameters like e′ and s′ are known to have independent prognostic value they also might be of use for risk stratification in obese children and adolescents.
- © 2010 by American Heart Association, Inc.