Hemodynamic Effects of the Anastomoses in the Modified Blalock–taussig Shunt: A Numerical Study Using a 0d/3d Coupling Method

Abstract

The modified Blalock-Taussig (BT) shunt is a palliative surgery which can help the tetralogy of Fallot (TOF) patient increase the blood oxygen saturation by interposing a systemic-topulmonary artery shunt. Two typical anastomotic shapes are frequently used in clinical practice: the end-to-side (ETS) and the side-to-side (STS) anastomosis. This paper examines the hemodynamic influence of the anastomotic shape in the modified BT shunt. Three models with different anastomotic shapes were reconstructed. The ETS anastomoses were applied in the first model. For the innominate artery (IA) and the pulmonary artery (PA) in the second model, the ETS and the STS anastomosis were applied, respectively. Finally, the STS anastomoses were applied in the third model. The 0D/3D coupling method was used to perform a numerical simulation by coupling the three-dimensional (3D) artery model with a zerodimensional (0D) lumped parameter model for the cardiovascular system. The simulation results showed that the perfusion into the left and right PA in Model 1 was unbalanced. Swirling flow appeared in the shunt in Model 3, but the shunt flow rate in Model 3 was lower. The ETS anastomosis at the PA may cause unbalanced blood perfusion into the left and right PA. Conversely, the STS anastomosis can make the blood perfusion more balanced. Otherwise, ¶ Corresponding author.the STS anastomosis at the IA could generate a swirling flow in the shunt which may provide a better hemodynamic environment while decreasing the pulmonary perfusion.

Multiscale modeling of a modified Blalock‐Taussig surgery in a patient‐specific tetralogy of Fallot

“…The maximum WSS in the pulmonary artery was observed directly under the anastomosis region and occurred at the peak‐systole and the end‐systole (Figure 9B,C). It had a value of 116 Pa which is in agreement with values reported in works reported by Zhao et al, 21 Corsini et al, 24 and Zhang et al 30 The maximum value for WSS in the pulmonary artery was observed in the impingement zone. Moreover, the locations nearer to the right long experienced higher WSS compared to the other half of the pulmonary artery.…”

“…The values for the WSS that we reported were in agreement with instantaneous WSS reported in prior studies 21,24,30 . The results suggest that the WSS in the pulmonary artery varies significantly, that is, around one order of magnitude, during the cardiac cycle.…”

“…Numerical simulation of the blood flow in different cases of TOF has been used for understanding the difference of various scenarios in treatment and using a different configuration of the shunt in three‐dimensional (3D) geometries, either idealized 17‐22 or patient‐specific 23‐25 . For instance, the numerical simulation approach was employed to simulate the blood flows in 3D domains for various configurations to investigate the pressure drop for the shunt, 17 the effect of the size of the shunt, 26 the effect of different angles, 27 the combination of different size and angles 18 or configurations 20,28 between the shunt and the pulmonary artery.…”

Hemodynamics of the string phenomenon in the internal thoracic artery grafted to the left anterior descending artery with moderate stenosis

“…The algorithm of coupling used in this study has been used in previous studies. (Ma et al, 2014;Zhao et al, 2015a;Zhao et al, 2015b) 3. Results…”

Numerical Simulation of the Effect of Pulmonary Vascular Resistance on the Hemodynamics of Reoperation After Failure of One and a Half Ventricle Repair

“…constructed an LPM for the blood circulation system of single ventricular patients to observe the recovery of different stenosis degrees of the pulmonary artery after the Gleen surgery. Zhao et al (2015) used the 0D/3D (three-dimensional) coupling model to study the hemodynamic effects of the anastomoses in modified Blalock-Taussig shunt. Corsini et al (2018) focused on coronary perfusion and aortic arch hemodynamics using computational multi-domain modeling.…”