Dasi Lakshmi P, Krishnankuttyrema Resmi, Kitajima Hiroumi D, Pekkan Kerem, Sundareswaran Kartik S, Fogel Mark, Sharma Shiva, Whitehead Kevin, Kanter Kirk, Yoganathan Ajit P
Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0535, USA.
J Thorac Cardiovasc Surg. 2009 Mar;137(3):560-4. doi: 10.1016/j.jtcvs.2008.04.036.
We quantify the geometric and hemodynamic characteristics of extracardiac and lateral tunnel Fontan surgical options and correlate certain anatomic characteristics with their hemodynamic efficiency and patient cardiac index.
The study was conducted retrospectively on 22 patients undergoing Fontan operations (11 extracardiac and 11 lateral tunnel operations). Total cavopulmonary connection geometric parameters such as vessel areas, curvature, and offsets were quantified using a skeletonization method. Energy loss at the total cavopulmonary connection junction was available from previous in vitro experiments and computational fluid dynamic simulations for 5 and 9 patients, respectively. Cardiac index data were available for all patients. There was no significant difference in the mean and minimum cross-sectional vessel areas of the pulmonary artery between the extracardiac and lateral tunnel groups. The indexed energy dissipation within the total cavopulmonary connection was strongly correlated to minimum cross-sectional area of the pulmonary arteries (R(2) value of 0.90 and P < .0002), whereas all other geometric features, including shape characteristics, had no significant correlation. Finally, cardiac index significantly correlated with the minimum pulmonary artery area (P = .006), suggesting that total cavopulmonary connection energy losses significantly affect resting cardiac output.
The minimum outlet size of the total cavopulmonary connection (ie, minimum cross section of pulmonary artery) governs the energy loss characteristics of the total cavopulmonary connection more strongly than variations in the shapes corresponding to extracardiac and lateral tunnel configurations. Differences in pulmonary artery sizes must be accounted for when comparing energy losses between extracardiac and lateral tunnel geometries.
我们对心外和侧隧道Fontan手术方案的几何和血流动力学特征进行量化，并将某些解剖特征与其血流动力学效率和患者心脏指数相关联。
本研究对22例行Fontan手术的患者（11例心外手术和11例侧隧道手术）进行回顾性分析。使用骨架化方法量化全腔静脉肺动脉连接的几何参数，如血管面积、曲率和偏移量。全腔静脉肺动脉连接处的能量损失分别来自之前对5例和9例患者的体外实验和计算流体动力学模拟。所有患者均有心脏指数数据。心外和侧隧道组之间肺动脉的平均和最小横截面积无显著差异。全腔静脉肺动脉连接内的指数能量耗散与肺动脉的最小横截面积密切相关（R²值为0.90，P <.0002），而所有其他几何特征，包括形状特征，均无显著相关性。最后，心脏指数与肺动脉最小面积显著相关（P =.006），表明全腔静脉肺动脉连接的能量损失显著影响静息心输出量。
全腔静脉肺动脉连接的最小出口尺寸（即肺动脉的最小横截面积）比心外和侧隧道构型对应的形状变化更强烈地决定了全腔静脉肺动脉连接的能量损失特征。在比较心外和侧隧道几何形状之间的能量损失时，必须考虑肺动脉大小的差异。
