An algebraic modeling of the modified assisted bidirectional Glenn

Infants born with a single ventricle require three stages of palliation. The long-term mortality rate for such patients is high, most associated with the unfavorable hemodynamics of the first and second stage operations. We previously proposed the assisted bidirectional Glenn (ABG) procedure and later the modified assisted bidirectional Glenn (mABG) procedure that offered several advantages over the conventional operations. However, the ABG could produce an SVC pressure that may be intolerable by patients. To avoid this complication, we relied on a specialized design of a nozzle in the mABG to improve the ejector pump effect in the SVC. Provided the variability in patient conditions, identifying the optimal nozzle design parameters requires expensive simulations that may not be feasible in a clinical setting. To overcome this challenge, in this study, we propose an algebraic model informed by CFD results that can accurately predict the key hemodynamics of the mABG without performing a CFD simulation. In this presentation, we will show the agreement between the proposed model and CFD as well as the behavior of the ABG circulation versus pulmonary vascular resistance and nozzle parameters.