Study on cardiac function in preterm infants / 中华围产医学杂志

ABSTRACT

Objective To investigate the features and influence factors of cardiac function in preterm infants.Methods One hundred and eleven preterm infants were divided into three groups according to the gestational age which was 28-31+6,32-33+6 and 34-36+6 weeks respectively.Fifty term-birth infants at gestational age of 37-41+6 weeks were taken as control group.The cardiac function was examined by SonoSite 180 PLUS color Doppler ultrasonic diagnostic apparatus.The parameters of cardiac function included heart rate,peak flow rate of aorta valve orifice (AV),peak flow rate of pulmonary artery valve orifice (PV),cardiac output (CO),stroke volume (SV),left ventricular end diastolic volume (LVEDV),left ventricular end systolic volume (LVESV),the ratio of early (E) and late (A) diastolic velocities of mitral and tricuspid valves (MVE/A,TVE/A).Within one week after delivery,the cardiac function was examined,and the cardiac function of preterm infants with different gestational age were compared.Another 162 preterm infants were divided into four groups according to the time at examination as 12 h-,24 h-,72 h-and 1 week-28 d.The influence factors of cardiac function were determined by multi-factor linear regression analysis.Results The AV,PV,CO,LVEDV,LVESV and SV increased with the increasing of gestational age.MVE/A (1.13±0.17,1.14±0.18,1.13±0.18) and TVE/A (0.90±0.16,0.90±0.13,0.90±0.15) of 28-31+6,32-33+6 and 34-36+6 weeks group were higher than those of control group (1.28±0.17 and 1.04±0.20),respectively (P＜0.05).PV of 72 h-group and 1 week-28 d group were higher than that of 12 h-group [(79.60±11.22) cm/s and (78.86±13.64) cm/s vs (72.61±8.56) cm/s](P＜0.05).The heart rate of 1 week-28 d group was higher than that of other three groups (P＜0.05).Both CO and SV were positively related to body weight and gestational age (r=0.55 and 0.36,0.61and 0.52,respectively,P＜0.05).Conclusions The left ventricular pump function increases with the increasing of gestational age,while the diastolic function of left and right ventricle of preterm infants does not change significantly in the first month of life.The PV of preterm infants significantly increases 72 h after delivery.The body weight and gestational age are important influence factors of cardiac function in preterm infants.