Blood flow assessment in echocardiography of hemodynamically significant patent ductus arteriosus in preterm infants

Background: In premature infants, patent ductus arteriosus (PDA) can lead to hemodynamic instability and prematurity-related complications. The conventional left atrial-to-aortic (LA/Ao) ratio for evaluating hemodynamically significant PDA (hsPDA) has demonstrated limited accuracy. We aimed to investigate the correlation between mitral inflow E–wave velocity, left pulmonary artery (LPA) end-diastolic velocity, and hsPDA in preterm infants. Methods: Single-center, retrospective cohort study included neonates born at a gestational age (GA) between 24 and 30 weeks. The echocardiographic parameters, including mitral E-wave velocity, LPA end-diastolic velocity and LA/Ao ratio were assessed with hsPDA requiring treatment. Results: Forty-nine infants were included, of whom 30 were diagnosed with hsPDA. The mitral E-wave (95% CI: 4.6–18.2, p = 0.0016) and LPA end-diastolic velocities (95% CI: 4.14–15.15, p = 0.0010) were significantly higher in infants with hsPDA, while the LA/Ao ratio exhibited no difference. Multivariate analysis revealed that lower GA, higher mitral E-wave, and LPA end-diastolic velocities were predictive of hsPDA. The receiver operating characteristic (ROC) analysis showed that these parameters offered better diagnostic accuracy than the LA/Ao ratio. Conclusion: Our findings suggest that mitral E wave and LPA end-diastolic velocities are more reliable echocardiographic markers for evaluating hsPDA in preterm infants than the conventional LA/Ao ratio. Impact: Assessment of dynamic blood flow is more reliable than the left atrium chamber size in evaluating the hemodynamic status of a PDA. Our result provides new criteria for assessing the hemodynamic significance of PDA. Utilizing this technique may yield evidence to assist clinical decision-making regarding PDA treatment. Multifactorial assessment, including birth gestational age and increased intracardiac or pulmonary blood flow velocity, provides more accurate prediction for a hsPDA.