Background:

Diabetes is an important disease that affects fetal development during pregnancy and causes metabolic disorders in newborns. Changes in serum glucose, ketone bodies, and somatomedin-C inhibitors in the diabetic pregnancies are responsible for the development of metabolic syndromes. The frequency of maternal hyperglycemia has reduced with careful monitoring during pregnancy of diabetic mothers. Nevertheless, morbidity in offspring of mothers with gestational diabetes mellitus (GDM) continues to be significant. We aimed to investigate the cardiac function of infants of mothers with GDM by echocardiographic (ECHO) Doppler and tissue Doppler methods and to evaluate their demographic features, somatomedin-C level and the relations them with each other.

Methods:

ECHO findings, laboratory data of newborns applied to our clinic between January and December 2016, and demographics of GDM mothers were examined. In the study, 108 neonates born to GDM mothers, and 100 healthy neonates (controls) were enrolled at postpartum 48th hour. Serum somatomedin-C levels were measured and detailed clinical and ECHO examination were performed. Isovolumetric relaxation (IVRT), isovolumetric contraction (IVCT), Myocardial Performance Index (MPI=ei Index) as an index that include both systolic and diastolic time intervals in expressing global systolic and diastolic ventricular functions [MPI: (IVRT + IVCT) / systolic ejection time] were calculated using both ventricular function M-mode, pulsed-wave and tissue Doppler ECHO methods. In addition, pulmonary arterial pressure (PAP) and tricuspid and mitral valves annular plan systolic excursion motions (TAPSE, MAPSE) were measured. Anamnesis and laboratory studies (fasting blood glucose [GHG] and glycosylated hemoglobin c [HbA1c]) measurements of all mothers were performed.

Results:

In the study group, 49 (45.4%) of infants were females and 59 were males (54.6%), the incidence of macrosomia was 4 (3.7%) in the study group and 2 (2.0%) in the control group. In comparison between the maternal groups, GDM mothers had significantly higher levels of fasting blood glucose (FBG) and HbA1c (p<0.0001). There was no significant difference in birth weight and somatomedin-C levels in neonates between two groups, but head circumference and height values were significantly higher in infants born to GDM mothers (p<0.05). In the echocardiographic examinations, small muscular ventricular septal defects were detected in 3 infants (2.77%) in study group, and 1 infant (1.0%) in control group. The M mode review revealed that diastolic end-interventricular septum thickness was significantly higher in IDMs group (p<0.001). In the evaluation of right ventricular function, MPI values were significantly higher in the infants of GDM group than control group (p<0.05). Also, IVCT, a diastolic function indicator, was significantly longer in the study group (p<0.05). There was a statistically insignificant decrease in TAPSE values in infants of GDM group (p>0.05). In evaluation of left ventricular function between groups, MPI and IVRT values were significantly higher in infants of GDM group (p<0.05), whereas MAPSE values were significantly decreased in the study group (p<0.05).

Conclusion:

Although infants of mothers with GDM were clinically normal in our study, we determined significant differences in diastolic parameters in addition to subclinical findings of ventricular septal thickness. We emphasize that cardiac involvement requires early diagnosis and neonatal approach even though complications in infants born to GDM mothers usually recover spontaneously. As expected, these infants are prone to various hyperglycemic adverse outcomes. Therefore, recognizing and treating hyperglycemia in time should be an important target for prevention of metabolic problems and deaths in severe cases.

Keywords: Newborn, gestational diabetes, hyperglycemia, echocardiographic findings, MPI, somatomedin-C