Department of Mechanical Engineering, Koc University, Istanbul, Turkey.
Department of Cardiovascular Surgery, Dr. Siyami Ersek Thoracic and Cardiovascular Surgery Training and Research Hospital, Istanbul, Turkey.
Interact Cardiovasc Thorac Surg. 2022 Jun 1;34(6):1095-1105. doi: 10.1093/icvts/ivac001.
To evaluate the hemodynamicdynamic advantage of a new Fontan surgical template that is intended for complex single-ventricle patients with interrupted inferior vena cava-azygos and hemi-azygos continuation. The new technique has emerged from a comprehensive pre-surgical simulation campaign conducted to facilitate a balanced hepatic flow and somatic Fontan pathway growth after Kawashima procedure.
For 9 patients, aged 2 to18 years, majority having poor preoperative oxygen saturation, a pre-surgical computational fluid dynamics customization is conducted. Both the traditional Fontan pathways and the proposed novel Y-graft templates are considered. Numerical model was validated against in vivo phase-contrast magnetic resonance imaging data and in vitro experiments.
The proposed template is selected and executed for 6 out of the 9 patients based on its predicted superior hemodynamic performance. Pre-surgical simulations performed for this cohort indicated that flow from the hepatic veins (HEP) do not reach to the desired lung. The novel Y-graft template, customized via a right- or left-sided displacement of the total cavopulmonary connection anastomosis location resulted a drastic increase in HEP flow to the desired lung. Orientation of HEP to azygos direct shunt is found to be important as it can alter the flow pattern from 38% in the caudally located direct shunt to 3% in the cranial configuration with significantly reversed flow. The postoperative measurements prove that oxygen saturation increased significantly (P-value = 0.00009) to normal levels in 1 year follow-up.
The new Y-graft template, if customized for the individual patient, is a viable alternative to the traditional surgical pathways. This template addresses the competing hemodynamic design factors of low physiological venous pressure, high postoperative oxygen saturation, low energy loss and balanced hepatic growth factor distribution possibly assuring adequate lung development.
25 October 2019, 280011928-604.01.01.
评估一种新的 Fontan 手术模板在患有中断下腔静脉-奇静脉和半奇静脉续连的复杂单心室患者中的血液动力学优势。新的技术源自一项全面的术前模拟活动，旨在促进 Kawashima 手术后肝血流平衡和体 Fontan 途径生长。
对 9 名年龄在 2 至 18 岁的患者进行了术前计算流体动力学定制，他们大多数术前氧饱和度较差。考虑了传统的 Fontan 途径和新的 Y 型移植物模板。数值模型经过体内相位对比磁共振成像数据和体外实验验证。
根据预测的优越血液动力学性能，选择并为 9 名患者中的 6 名执行了新的模板。对该队列进行的术前模拟表明，来自肝静脉（HEP）的血流未到达所需的肺部。通过右侧或左侧移动全腔肺动脉连接吻合位置定制的新型 Y 型移植物模板导致 HEP 血流显着增加到所需的肺部。HEP 到奇静脉直接分流的定向被发现很重要，因为它可以改变血流模式，从位于尾部的直接分流的 38%变为头部配置的 3%，并且具有明显的反向血流。术后测量证明，在 1 年随访期间，氧饱和度显着增加（P 值= 0.00009）至正常水平。
如果为个体患者定制新的 Y 型移植物模板，则是传统手术途径的可行替代方案。该模板解决了低生理静脉压、高术后氧饱和度、低能量损耗和平衡肝生长因子分布等相互竞争的血液动力学设计因素，可能确保足够的肺部发育。
IRB 批准日期和编号：2019 年 10 月 25 日，280011928-604.01.01。
