Fetal cardiac dysfunction: effects on perinatal outcomes in preterm infants

Abstract

Objective. To study the importance of fetal cardiac dysfunction in the genesis of perinatal brain damage in premature newborns. Patients and methods. A prospective cohort comparative study included 59 preterm infants with gestational age from 26 to 32 weeks and body weight from 590 to 1990. Newborns were divided into 2 groups at the 1st month of life: the main group (n = 38), which included children with structural brain lesions, and the control group (n = 21) with favorable neurological outcomes. There were no statistically significant differences in either body weight or gestational age between the groups. At the antenatal stage, all underwent ultrasound doppler sonography of uteroplacental blood flow, and the cerebral-placental ratio was calculated. The following markers were determined at the 1st day of postnatal life: levels of lactate, cerebral natriuretic propeptide and soluble type 2 tumor suppressor in the umbilical cord blood of a newborn (enzyme-linked immunosorbent assay); neurosonography of the brain with the determination of blood flow and doppler echocardiography. Neurological outcomes were assessed after 1 month of life after the control neurosonography of brain. The data are presented in the form of median, maximum and minimum values – Me [min; max]. The obtained data were processed using the Statistica 6.1 program. The Mann–Whitney and Fisher χ2 criteria with the Yeats correction were calculated. The differences were considered significant at p equal to 0.05. Results. The pulsation index in the umbilical cord artery was significantly higher (1.270 [1.120; 1.320] versus 0.984 [0.798; 1.120]) in the fetuses of the main group, Its values indicating severe disorders of fetal-placental hemodynamics were more often recorded (in 15–39.5% cases versus 4–19.1%). The significant decrease in the cerebroplacental ratio was significantly more often recorded (in 18–47.4% cases versus 2–9.5%) in the same group. The levels of lactate (3.6 [2.1; 5.2] versus 2.25 [1.3; 3.05] mmol/L) and cerebral natriuretic propeptide (243.2 [84.17; 1385] versus 111.6 [64.8; 2903] pg/ml, respectively) were significantly elevated in the umbilical cord blood, in newborns of the main group. The newborns of the main group had significantly lower levels of systolic, diastolic and mean blood pressure, at the first hours of life. They also had a reduced level of blood flow in the superior vena cava (Me = 65 ml/kg/min; 9 (23.7%) children had a periventricular leukomalacia, 18 (47.4%) – intraventricular hemorrhages of the II–III degree, and 2 (5.3%) had a stroke. Conclusion. It is very important to pay attention of pediatricians-neonatologists to the antenatal period. Treating the fetus as a patient, early assessment of hemodynamics and timely diagnosis of fetal cardiac dysfunction and other developmental abnormalities will reduce the incidence of disabling perinatal diseases and the level of perinatal mortality. Key words: antenatal diagnosis, umbilical cord blood lactate, prematurity, perinatal brain damage, placental insufficiency, fetal cardiac dysfunction