According to Zhang et al., infants with HF related to congenital heart disease presented apart from alterations of the intestinal microbial population predominance of Enteroccocus, which may induce the secretion of certain inflammatory mediators, such as interleukin-1β (IL-1β), interleukin-4 (IL-4), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α), thus favoring the evolution of HF [85]. Here, IL6 is linked to hydrops fetalis.