Pulsatile blood flow in total cavopulmonary connection: a comparison between Y-shaped and T-shaped geometry

Single-ventricle anomaly is a hereditary heart disease that is characterized by anatomical malformations. The main consequence of this malformation is desaturated blood flow, which without proper treatment increases the risk of death. The classical treatment is based on a three-stage palliative procedure which should begin from the first few days of patient's life. The final stage is known as Fontan procedure, in which inferior vena cava is directly connected to pulmonary arteries without going through the ventricle. This connection is called total cavopulmonary connection (TCPC). After surgery, the single ventricle supplies adequate and saturated systemic blood flow to the body; however, TCPC contains low pressure and low flow pulsatility. To overcome this problem, a new method is proposed wherein pulsatile blood will be directed to the TCPC through the stenosed main pulmonary artery. In this study, through the use of Computational Fluid Dynamics, T-shaped (MRI-based) and Y-shaped (computer-generated) geometries are compared in order to determine the influence of this modification on pulsation of blood flow as well as energy loss in pulmonary arteries. The results indicate that energy loss in Y-shaped geometry is far less than T-shaped geometry, while the difference in flow pulsatility is insignificant.