Circulatory Adaptation in Newborn Infants of Strictly Controlled Diabetic Mothers

Abstract

Possible relations between neonatal circulatory function and maternal diabetic control were investigated in 22 infants of strictly controlled diabetic mothers during the first 2 days after birth. Eleven infants were delivered vaginally (V) and 11 infants by elective cesarean section (S). Maternal diabetes was more severe in the latter group. Half of the infants had one or more episodes of neonatal morbidity although none presented symptomatic hypoglycemia. Plasma glucose FFA and C-peptide were measured at birth and 3-6 hours later together with skinfold thickness; heart size was determined by X-ray at 24-28 hours; stroke volume and cardiac output were repeatedly determined by transthoracic impedance and ECG. C-peptide at birth was higher in group S than in V. C-peptide in both groups were neither related to glucose or FFA nor to birthweight or skinfold thickness. Infants with neonatal complications including cardiomegaly had the highest C-peptide values. Skinfold was positively correlated to maternal pregnancy glucose level, birthweight percentile and infant heart volume. Mean values for stroke volume and cardiac output were similar in both groups and not different from normal controls when related to body weight. Heart volume and stroke volume were significantly related. ECG abnormalities were seen in 6 infants who showed cardiomegaly on X-ray. We suggest that the present finding of an association between elevated C-peptide concentration at birth and the occurrence of neonatal complications including cardiomegaly and ECG abnormalities could be the consequence of functional hyperinsulinism and that the cardiomegaly is of adaptive type.

Growth and Function of Human Fetal Heart in Normal, Hypertensive and Diabetic Pregnancy

“…All these phenomena resulted in small stroke volume and cardiac output in relationship to the size of the fetus. In contrast, previous neonatal studies of diabetic infants have revealed that radiologically measured heart volume in these infants correlates with the birthweight and skinfold thickness (17). In fact, reversible cardiomyopathy and cardiomegaly in the absence of any congenital heart malformation has been described as a common neonatal problem of these newborns (18).…”

Cardiac changes in infants of diabetic mothers

“…Cardiomegaly could present in IDMs without hypertrophic cardiomyopathy due to persistent foetal circulation or transient increase in pulmonary pressure due to increased interstitial pulmonary fluids, which causes transient tachypnoea of the newborn (because of increased incidence of Caesarean section). Neonatal hypoglycaemia, which is more frequent in IDMs, could lead to cardiomegaly and electrocardiographic abnormalities[ 39 ]. Studies also showed that about 8% of IDMs have bradycardia[ 40 ].…”

Heart changes in a fetus of a diabetic mother

“…In addition, neonatal hypoglycaemia, which is more frequent in children of diabetic mothers, may be related to fetal hyperinsulinism, high C-peptide levels at birth, and β-cell function disturbance, leading to neonatal complications such as cardiomegaly and electrocardiographic abnormalities [6].…”