Feeding tubes, formula exposure, aortic cross-clamp, and socioeconomic status were associated with altered gut microbiome diversity in newborns with CHD, and further study is needed to determine the causal relationships leading to gut microbial dysbiosis in newborns in the cardiac intensive care unit.
Newborns with CHD had higher gut microbiome alpha diversity and dissimilar beta diversity compared with matched healthy controls.
Gut microbiome beta diversity differed between newborns with CHD receiving human milk and those receiving formula.
Beta diversity differed between newborns with CHD receiving fortified versus nonfortified human milk.
Beta diversity differed between newborns receiving naso-orogastric tube feeds and those receiving other feeding routes.
Newborns with CHD fed only human milk had a higher relative abundance of Haemophilus.
Longer aortic cross-clamping duration was associated with lower relative abundance of Streptococcus, though the result was not statistically significant at the conventional threshold.
Newborns with CHD with higher socioeconomic deprivation had a higher relative abundance of Enterococcus.
Overall, feeding tubes, formula exposure, aortic cross-clamp, and socioeconomic status were associated with altered gut microbiome diversity in newborns with CHD.
This study looked at the gut bacteria of newborns with congenital heart disease (CHD) compared with healthy newborns. Researchers collected stool samples at three points around the time of heart surgery from 41 babies with CHD and 40 matched healthy babies. They found that the gut bacteria of babies with CHD were more varied and differed in makeup from those of healthy babies. Among babies with CHD, the gut bacteria also differed depending on how they were fed. Differences appeared between human milk and formula, between fortified and nonfortified human milk, and between tube feeding and other feeding routes. Babies fed only human milk had more Haemophilus. Babies from areas with higher socioeconomic deprivation had more Enterococcus. Longer aortic cross-clamp time during surgery was linked to less Streptococcus, but that finding was not statistically significant. This research suggests that hospital care practices and social and environmental circumstances may shape the developing gut bacteria of newborns with CHD. Because the study found associations rather than proving cause and effect, the authors say more research is needed to understand what leads to unhealthy gut bacterial balance in babies in the cardiac intensive care unit.
John A, Bai J, Calamaro C, Brown A, Keiffer R, Huang H, et al.. (2026). Social and Environmental Exposures and the Developing Gut of Newborns With Congenital Heart Disease.. American journal of critical care : an official publication, American Association of Critical-Care Nurses. https://doi.org/10.4037/ajcc2026557