Abstract 10808: Speckle Tracking And Conventional Doppler Analysis Of Cardiac Function In Small For Gestational Age Infants
Aims: Speckle derived strain echocardiography is an emerging technique for assessing cardiac function. Small for gestational age infants are characterised by perinatal mortality and morbidity. The objective was to compare strain and conventional Doppler indices between small for gestational age (SGA) and appropriate for gestational age (AGA) infants and to ascertain correlations with arterial biophysical parameters. Our hypothesis was that fetal programming and adaptation to growth restriction induces changes in cardiac and arterial indices.
Methods: A prospective observational echocardiographic study of cardiac and arterial indices was done. Demographic and echocardiographic data for 20 inborn term SGA infants weighing < 3rd centile for gestational age were compared with 20 AGA infants. Arterial indices measured included stiffness, impedance and strain elastic modulus.
Results: The gestational age of both groups was comparable (39.1 ± 1.3 vs 38.9 ± 1.4 weeks). Ponderal index was significantly lower in SGA infants than the term AGA infants. Left ventricular global longitudinal strain (GLS) was significantly impaired in the SGA infants (-15.9 % ± 2.1 vs -21.3 % ± 2.8, p <0.001). A basal to apical gradient was noted in segmental strain. Left ventricular output was lower in SGA infants (170 ± 31 vs 197 ± 39 ml/kg/min, p=0.017). Diastolic dysfunction (reduced E and A wave velocities, higher E/A ratio [1.08 ± 0.16 vs 0.85 ± 0.07]) and prolonged isovolumic relaxation time [73 ± 6.2 vs 62.6 ± 3.6 ms]) were noted in the SGA infants. Aortic intima media thickness (aIMT) was noted to be significantly greater in SGA infants (822 ± 105 vs 694 ± 52 μm). Arterial wall stiffness index and input impedance were significantly greater in the SGA infants. Significant correlations were noted between GLS and arterial stiffness (r = -0.4, p = 0.03), weight indexed stiffness (r = -0.45, p=0.02) and pressure - strain elastic modulus (r = - 0.49, p = 0.01).
Conclusions: Impairment in myocardial deformation was noted in the presence of altered arterial biophysical properties in the SGA infants. The findings complement the information on the association between in-utero growth and cardiovascular morbidity in later life.
- © 2013 by American Heart Association, Inc.