Gestational Diabetes linked to alteration in fetal heart function: JAMA

Several studies consistently report the consequences of maternal diabetes in utero increases the risk of cardiovascular disease in the offspring and cardiovascular changes appear from fetal life and extend to adolescence and adulthood.

Fetuses in women with gestational diabetes (GD) show evidence of cardiac dysfunction and morphological changes. However, it is uncertain whether glycemia or the adverse maternal underlying risk factor profile is the main driver for fetal cardiac remodeling.

To assess cardiac morphology and function at midgestation in fetuses of mothers prior to development of GD and compare them with those of unaffected controls Dr Iulia Huluta, MD and team conducted a observational study and reported in pregnancies at risk for development of GD compared with those that were not, fetal interventricular thickness and left atrial area at midgestation were increased by 2.2% and 14%, respectively. The results are published in JAMA Pediatrics.

The study was prospective nonintervention screening study at 19 to 23 weeks’ gestation, fetal cardiac morphology and function were assessed in all participants. Pregnancy complications were obtained from the medical records of the women. Conventional and more advanced echocardiographic modalities, such as speckle tracking, were used to assess fetal cardiac function in the right and left ventricle. The morphology of the fetal heart was assessed by calculating the right and left sphericity index.

The key findings of the study are

• The 5620 included patients had a mean age of 33.6 years. In 470 cases, the women were diagnosed with GD after the midgestation echocardiographic assessment (8.4%).

• Women with GD, compared with the non-GD group, were older, had higher BMI, higher prevalence of family history of diabetes, non-White ethnicity, chronic hypertension, and GD in a previous pregnancy.

• In fetuses of the GD group compared with the non-GD group, there was mild increase in interventricular millimeter thickness (0.04; 95% CI, 0.03-0.06 mm) and left atrial area (0.04; 95% CI, 0.04-0.05).

• The left and right functional indices were comparable between groups with the exception of left ventricular ejection fraction, which was marginally improved in the GD group (0.02; 95% CI, 0.03-0.03).

The present study demonstrates that prior to development of GD, there was mild alteration in fetal cardiac morphology without affecting cardiac function. This suggests that the adverse maternal risk factor profile and not only the glycemia might contribute to cardiac remodeling noted in fetuses of women with GD the researchers ended.

Reference: Huluta I, Wright A, Cosma LM, Hamed K, Nicolaides KH, Charakida M. Fetal Cardiac Function at Midgestation in Women Who Subsequently Develop Gestational Diabetes. JAMA Pediatr. 2023 Jul 1;177(7):718-725. doi: 10.1001/jamapediatrics.2023.1174. PMID: 37184868; PMCID: PMC10186208.