Evaluation of left ventricular function parameters in term and preterm neonates at the 1st week of postnatal life
Abstract
BACKGROUND The period of time of life where the most dramatic physiologic changes occur is the neonatal period. There are marked physiological alterations that take place during this time, particularly concerning the heart and circulation.
But, the transformation of the fetal into a neonatal circulation in preterm infants is inadequately investigated and the time to choose for comparison between neonates born prematurely and full-term neonates are controversial.
AIMS This study focused on comparison of left ventricular systolic and diastolic function between preterm and term neonates during the postnatal cardiovascular transitional period in the 1st week of life following closure of the major fetal shunts.
METHODS Via the use of echocardiography, we evaluated some of the systolic and diastolic parameters of the left ventricular function in 30 preterm neonates at the 1st week of postnatal life and 50 term neonates after closure of the patent ductus arteriosus on 1st the week of postnatal life. Via the use of M‑mode ultrasound imaging technique, we measured left ventricular dimensions to estimate fractional shortening FS %. By two dimensional echocardiography 2D ECHO we measured ejection fraction EF% by Simpson’s biplane method and left ventricular outflow tract LVOT diameter. Through pulsed‑wave Doppler echocardiography, we estimated stroke volume SV and cardiac output CO, and left ventricular diastolic function through measuring the (E and A waves, E/A ratio).
RESULTS We identified a significant difference statistically between the study groups for all variables. Compared with term neonates, preterm infants in the 1st week of life had reduced FS% and EF%, SV and left ventricular CO and reduced transmitral filling indicating some degree of systolic and diastolic function impairment due to insufficient time for extra uterine life physiological adaptations.
CONCLUSIONS Preterm neonates at the 1st week of postconceptional age have reduced left ventricular function systolic and diastolic parameters.
