Association Between Pulsatility Index and the Development of Necrotizing Enterocolitis in Infants with Congenital Heart Disease

Infants with congenital heart disease are known to have higher rates of necrotizing enterocolitis (NEC) which is associated with poorer outcomes. Although the etiology is recognized as distinct from the premature neonatal population, there is not a universal consensus regarding etiology or specific risk factors. In this retrospective single-institution case-control study, we assessed whether aortic pulsatility index (PI) as detected via ultrasound might be associated with NEC in neonates undergoing cardiac surgical repair within the first month of life. The study identified 30 participants who developed NEC and 50 matched controls. Baseline demographic and surgical characteristics were similar between groups. Patients who developed NEC had higher mortality (26% vs 4%, p < 0.01). Standard PI and the modified pulsatility values were calculated manually and underwent logistic regression. The median log PI of the NEC cohort was higher compared to the lowest control PI (0.68 vs 0.48, p = 0.03); the median log PI of the NEC cohort was significantly lower than the highest PI of the control cohort (0.61 vs 0.98, p = 0.05). The modified pulsatility index demonstrated similar trends with the median log MODPI of the NEC cohort being significantly greater than that of the control cohort (3.9 vs. 3.1, p = 0.01). Infants with congenital heart disease who develop NEC have a higher PI and MODPI when compared to the lowest control PI. This suggests that infants with a higher baseline PI may be at increased risk for developing NEC.