Evaluation of personalized right ventricle to pulmonary artery conduits using in silico design and computational analysis of flow

Objectives: Right ventricle to pulmonary artery (RV-PA) conduits are required for the surgical management of pulmonary atresia with ventricular septal defect and truncus arteriosus. Bioengineered RV-PA connections may address some of the shortcomings of homografts and xenografts, such as lack of growth potential and structural deterioration and may be manufactured to accommodate patient-specific anatomy. The aim of this study was to develop a methodology for in silico patient-specific design and analysis of RV-PA conduits. Methods: Cross-sectional imaging was obtained from patients with truncus arteriosus (n = 5) and pulmonary atresia with ventricular septal defect (n = 5) who underwent complete repair with a RV-PA conduit. Three-dimensional models of the heart were constructed by segmentation of the right ventricle, existing conduit, branch pulmonary arteries, and surrounding structures. A customized conduit design for each patient was proposed. Computational fluid dynamics analysis was performed and outputs, including wall shear stress and energy loss, were used to compare the performance of the existing conduits and the customized geometries. Results: In this study, a methodology for patient-specific analysis of RV-PA conduit in silico was developed. The results of simulations for 10 patients showed between 23% and 56% decrease in the average wall shear stress and between 24% and 87% reduction in average power requirements in customized designs compared with the stenosed conduits, translating into better hemodynamic performance. Conclusions: Creation of an optimal conduit for an individual patient can be achieved using surgeon-guided design and computational fluid dynamics analysis. Manufacture of personalized RV-PA conduits may obviate the need for surgical customization to accommodate existing materials and provide superior long-term outcomes.