Numerical investigation on the influence of ductus arteriosus angle on fetal aortic hemodynamics

Coarctation of the aorta (CoA) is a common congenital heart defect characterized by narrowing of the aortic isthmus, often between the left subclavian artery and the ductus arteriosus (DA). Early detection of CoA is critical, yet it remains commonly undiagnosed in fetuses. Recent studies have suggested that the angle between the DA and the aorta may play a role in the development of CoA. However, the influence of DA angle on aortic hemodynamics remains poorly understood. This study aims to investigate the effects of varying DA angles on fetal aortic hemodynamics using computational fluid dynamics (CFD) models. We reconstructed three-dimensional models of healthy fetal aorta using three-dimensional/four-dimensional (3D/4D) fetal echocardiography and adjusted the DA angle to simulate different configurations. Key hemodynamic parameters were analyzed for each angle. Our results showed significant variations in blood flow and shear stress across different DA angles, with notable differences in regions of the descending aorta and aortic arch. Specifically, certain DA angles, such as 150° and 120°, led to higher energy loss and oscillatory shear index, while others, such as 30° and 15°, demonstrated more stable flow patterns. This study provided valuable insights into the role of DA angle in fetal aortic hemodynamics and suggests that variations in DA positioning may contribute to the pathogenesis of CoA. These findings highlight the potential importance of the DA angle in the etiology and diagnosis of CoA and may inform future clinical assessments and interventions for congenital heart diseases.