Hu Jie, Wang Qian, Tong Zhirong, Shen Juanya, Liu Jinlong, Sun Yanjun, Zhang Haibo
Department of Pediatric Cardio-Thoracic Surgery, Shanghai Children's Medical Center, Shanghai, China.
Department of Radiology, Shanghai Children's Medical Center, Shanghai, China.
Thorac Cardiovasc Surg. 2020 Jan;68(1):38-44. doi: 10.1055/s-0038-1677490. Epub 2019 Jan 22.
The desirable distance, defined as offset, between the central line of the superior vena cava (SVC) and the intra-atrial conduit after an intra-atrial conduit (IAC) Fontan's procedure remained unclear. We compared the hemodynamic features using virtual surgery with different offset designs in our study.
Three-dimensional models of IAC Fontan's procedure were reconstructed according to the magnetic resonance imagings (MRIs) of three patients, then four models for each patient with different offsets equaling 100, 67, 33, and 0% of the diameter of the IVC were reconstructed. Computational fluid dynamics (CFD) were performed in each model to predict the best hemodynamic features, including streamlines of blood flow, wall shear stress (WSS), energy loss (EL), and the hepatic flow distribution (HFD) ratio.
Comprehensive evaluation of WSS, EL, and HFD revealed than an offset of 33% presents the best hemodynamic performance among the three patients modeled. In patient A, an offset of 33% resulted in the best HFD (left pulmonary artery/right pulmonary artery [LPA/RPA] = 35/65%). In patient B, the best trade-off between HFD (35/65%), and WSS was achieved with an offset of 33%. In patient C, EL peaked at an offset of 0% and significantly dropped at an offset of 33% with a desirable HFD (60/40%).
We verified that the offset distance influences hemodynamic performance in IAC Fontan's procedure. Considering several hemodynamic parameters, the best trade-offs between hemorheology, pulmonary perfusion, and energy efficiency were achieved at an offset of 33%. This distance should be taken into consideration and optimized during the surgical planning for the IAC Fontan's procedure.
在心房内管道（IAC）Fontan手术之后，上腔静脉（SVC）中心线与心房内管道之间的理想距离（定义为偏移量）仍不明确。在我们的研究中，我们使用不同偏移设计的虚拟手术比较了血流动力学特征。
根据三名患者的磁共振成像（MRI）重建IAC Fontan手术的三维模型，然后为每位患者重建四个偏移量不同的模型，偏移量分别等于下腔静脉直径的100%、67%、33%和0%。对每个模型进行计算流体动力学（CFD）分析，以预测最佳血流动力学特征，包括血流流线、壁面剪应力（WSS）、能量损失（EL）和肝血流分布（HFD）比率。
对WSS、EL和HFD的综合评估显示，在建模的三名患者中，33%的偏移量呈现出最佳的血流动力学性能。在患者A中，33%的偏移量导致最佳的HFD（左肺动脉/右肺动脉[LPA/RPA]=35/65%）。在患者B中，偏移量为33%时，在HFD（35/65%）和WSS之间实现了最佳平衡。在患者C中，EL在偏移量为0%时达到峰值，在偏移量为33%时显著下降，同时具有理想的HFD（60/40%）。
我们证实了偏移距离会影响IAC Fontan手术中的血流动力学性能。综合考虑多个血流动力学参数，在偏移量为33%时，在血液流变学、肺灌注和能量效率之间实现了最佳平衡。在IAC Fontan手术的手术规划过程中，应考虑并优化这个距离。
