Childhood cardiovascular assessment
Conventional and tissue Doppler echocardiography was performed using a Canon Aplio i900 machine (PST-50BT neonatal transducer) according to the guidelines of the American Society of Echocardiography (9). Measures which were assessed were indices of systolic and diastolic left ventricular function, including peak systolic mitral annular tissue velocity and midwall fractional shortening and peak mitral annular velocities in early diastole (e’), a measure of diastolic relaxation. The ratio of early diastolic transmitral flow velocity E/E’ was calculated. Left ventricular mass (LVM) measurements were normalized to body surface area as indexed LVM (LVMI). Speckle tracking analysis was also performed to calculated left ventricular global longitudinal systolic function. Right ventricular systolic function was also assessed by tricuspid annular plane systolic excursion.