Introduction: Offspring of diabetic mothers have five times higher risk of cardiovascular abnormalities than in normal pregnancies. These cardiac anomalies involve fetal cardiac morphological and functional changes. Here, we investigate subclinical cardiovascular abnormalities, including structural and functional changes among infants of diabetic mothers.
Material and methods: A prospective cohort study was carried out from March 2017 to September 2020 at a South Indian tertiary care center. One hundred ninety-eight newborns delivered from non-diabetic mothers, well-controlled diabetic mothers (WCDM), and poorly controlled diabetic mothers (PCDM) were studied. Neonates and infantile echocardiographic imaging were performed at the first week of life, at 6-weeks, and 6-months of life. Cardiac structure and function were assessed using 2D, M-mode, Conventional Doppler, and Tissue Doppler imaging.
Results: Out of the total (198) infants, 66 (33.3%) were from the non-diabetic (control) mothers, 60 (30.3%) from the WCDM, and 72 (36.4%) were from the PCDM groups. In both WCDM and PCDM groups, the mean gestational ages at birth were shorter than the control group (37.19 ± 0.82, 36.02 ± 2.15, and 37.91 ± 1.33 weeks respectively). There was a high incidence of neonatal hypoglycemia (p-value <0.001), NICU stay >7 days (p-value <0.018), and persistent fetal transitional cardiac shunt (p-value <0.03) among poorly controlled DM group in comparison to others. Tissue deformation imaging showed a significant reduction in left ventricular global strain and strain rate in the neonatal heart from poorly controlled diabetic mothers. Myocardial wall thickness among neonates of diabetic mothers was higher compared to controls. LV TEI was higher in PCDM groups in comparison with WCDM and control groups; (0.59 ± 0.11, 0.46 ± 0.35, and 0.37 ± 0.12 respectively, p-value =0.01). Similarly, RV TEI was high in the PCDM (0.56 ± 0.09) group compared to the WCDM group (0.33 ± 0.12) and control group (0.28 ± 0.10).
Conclusions: Infants of diabetic mothers are at higher risk of developing cardiac abnormalities, including structural and functional defects. The highest increase in interventricular septal thickening found in poorly controlled diabetic mothers' neonates will disrupt both ventricles' functions, followed by WCDM and the control group.
Keywords: Cardiac anomalies; Echocardiography; Gestational diabetes; Infant health; Tissue Doppler imaging; Tissue deformation.