Neonatal cardiac dysfunction in intrauterine growth restriction

Abstract

Background:The early postnatal cardiovascular consequences of intrauterine growth restriction (IUGR) have not been completely elucidated. This study aimed to evaluate the effect of IUGR on neonatal myocardial function and cardiovascular adaptation to extrauterine life. Methods: Conventional and tissue Doppler echocardiographic parameters were compared on the second and fifth postnatal day between 30 IUGR and 30 appropriate-forgestational age (AGA) neonates. results: IUGR neonates presented relative interventricular septum (IVS) hypertrophy (IVS to left ventricular (LV) posterior wall diastolic ratio: median IUGR-AGA difference of 0.05 (interquartile range: 0.04-0.06); P = 0.020), relative LV dilatation (wall thickness to end-diastolic LV dimension difference of 0.12 (0.06-0.16); P = 0.012), and increased left myocardial performance index (MPI difference of 0.19 (0.05-0.28); P = 0.012). Repeated measurements ANOVA revealed a different pattern of change in LV stroke volume (LVSV; P < 0.001), LV cardiac output (LVCO; P < 0.001), MPI (P < 0.001), and heart rate (HR; P = 0.025) between AGA and IUGR infants. From the second to the fifth postnatal day, AGA neonates presented a decrease in MPI and HR with an increase in LVSV and LVCO. IUGR neonates failed to achieve similar changes in MPI, HR, and LVSV, whereas their LVCO decreased. conclusion: IUGR neonates present changes in cardiac morphology and subclinical myocardial dysfunction, which may result in an altered pattern of cardiovascular adaptation to extrauterine life. i ntrauterine growth restriction (IUGR), defined as the inability of a fetus to achieve its genetically determined potential size, is associated with increased risk of perinatal complications and neonatal morbidity (1). Epidemiological evidence also suggests a strong relationship between IUGR and cardiovascular disease in adulthood (2), supporting the existence of a maladaptive programming process in utero, which affects cardiovascular system in the long term (3). Previous studies have shown that chronic intrauterine substrate deprivation is associated with changes in ventricular geometry and "cardiomyopathy-like" myocardial dysfunction in the fetus (4-7). Alterations in cardiovascular adaptation to extrauterine life have also been reported in neonates exposed to IUGR, but these findings were only hypothetically related to an impairment in myocardial function (8).Traditionally, the assessment of cardiac performance in infants relies on conventional echocardiographic indexes (9). Tissue Doppler imaging (TDI) is a relatively new echocardiographic technique, which enables assessment of ventricular mechanics by providing information on myocardial motion and timing of cardiac events with high temporal and spatial resolution (10). Accumulating evidence from studies in neonates (11-15) and children (16)(17)(18) suggests that specific TDI parameters, such as peak myocardial velocities and myocardial performance index (MPI) (19), are more sensitive markers of ventricular dysfunction than those derived from con...

Intrauterine growth restriction: impact on cardiovascular development and function throughout infancy

“…The MPI has been shown to progressively increase with fetal deterioration (7) and it appears to have a negative association with perinatal outcome (including 5-min Apgar score, cord pH, and perinatal mortality) (7,46). An increased MPI has also been found in neonates following IUGR (37,40,43) and has even been reported in infants born growth restricted up to 3 mo of age (40), suggesting that cardiac dysfunction, although subclinical, can persists beyond the fetal and neonatal period. …”

“…They are however more likely to result from increased afterload in relation to high placental resistance, since most growth-restricted fetuses are capable of maintaining their cardiac output (7,48,50) and the majority of studies also report normal postnatal systolic function (10,(36)(37)(38)(39)(40)(41)51). Fractional shortening and ejection fraction, both measurements that give an indication of left ventricular pump function, have been found to be similar in growth-restricted and AGA neonates and infants (10,(36)(37)(38)(39)(40)(41). In most studies, cardiac output of neonates and infants born growth restricted has also been found comparable to controls (36)(37)(38)40,51).…”

“…Nevertheless, prolonged exposure to increased afterload and cardiac remodeling may eventually result in systolic dysfunction. A reduction in stroke volume in neonates born growth restricted has been reported in a few studies (26,37,51), although a compensatory increase in heart rate usually maintains cardiac output (37,51). In one study, however, the reduction in stroke volume was not compensated for by an increase in heart rate, resulting in a lower cardiac output in growth restricted compared to AGA term neonates (26).…”

“…Dilation of the left atrium has been demonstrated by an increased left atrium/aortic root ratio in comparison to AGA controls (26). Cardiac changes in IUGR are thus most often described as cardiomyopathy-like, with dilated ventricles and a more globular cardiac shape compared to controls (10,26,32,34,(37)(38)(39)(40)42). …”

Удосконалення Діагностики Діастолічної Дисфункції Шлуночків Серця В Новонароджених За Даними Тканинної Допплерометрії

“…Tissue Doppler imaging helps to evaluate ventricular mechanics by providing information on the movement of myocardium and fibrous rings, with the assessment of time and velocity indices [9]. Moreover, spectral tissue Doppler imaging provides a more accurate assessment of diastolic function of heart ventricles [10].…”