Necrotizing enterocolitis in newborns with congenital heart defects: incidence and risk factors

Necrotizing enterocolitis (NEC) is a serious complication in newborns with critical congenital heart disease (CHD), prolonging hospital stay, worsening neurological prognosis, and increasing mortality. The leading role in the pathogenesis of NEC in these infants is the violation of mesenteric perfusion. A decrease in arterial blood oxygenation may be an additional risk factor for intestinal hypoxia. Objective. To assess the incidence and risk factors for NEC in full-term newborns with CHD born in 2019–2021 at the Perinatal Center of Almazov National Research Medical Center. Patients and methods. The article presents an analysis of the frequency and risk factors of NEC in children with CHD born at the Almazov National Medical Research Centre in 2019–2021. In the group of critical and duct-dependent CHD (n = 264), the overall incidence of NEC was 15.9% (42 cases). The frequency of surgical stages of NEC (IIIA) was 1.1% (3 cases). In the preoperative period, there was a trend towards a higher frequency of inotropic therapy in a subgroup of children who subsequently developed NEC. NEC in newborns with duct-dependent CHD developed mainly in the early postoperative period after cardiac surgery. In children with duct-dependent pulmonary blood flow, a higher incidence of NEC after surgery was noted compared to children with duct-dependent systemic blood flow. Conclusion. Risk factors for NEC in the postoperative period were arterial hypotension and hemodynamically significant cardiac arrhythmias. Dysbiosis of the gut microbiota and changes in microbial metabolism may be additional risk factors for NEC in children with CHD. Key words: necrotizing enterocolitis, risk factors, congenital heart disease, cardiopulmonary bypass, intestinal microbiome, metabolomics