Noninvasive fluid dynamic power loss assessments for total cavopulmonary connections using the viscous dissipation function: a feasibility study.
Noninvasive fluid dynamic power loss assessments for total cavopulmonary connections using the viscous dissipation function: a feasibility study.
复制标题
使用粘性耗散函数对总腔肺连接进行无创流体动态功率损失评估：可行性研究。
DOI：
10.1115/1.1384875
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发表时间：
2001
期刊：
影响因子：
--
通讯作者：
Yoganathan,AP
中科院分区：
文献类型：
--
作者：
Healy,TM;Lucas,C;Yoganathan,AP
全腔静脉肺动脉连接（TCPC）作为单心室先天性心脏缺陷的有效姑息治疗已显示出巨大的前景。然而，由于该手术导致右心完全搭桥，流体动力损失可能对术后患者的成功起着至关重要的作用。过去的研究主要集中在使用控制量方法确定功率损耗。如果没有高侵入性压力测量，此类方法不能直接应用于临床。这项工作提出使用粘性耗散函数作为基于速度梯度的流体动力功率损失估计的工具。为了验证这项技术，在 TCPC 模型中进行了数值模拟，该模型包含 13.34 毫米（一个腔静脉直径）的腔室偏移量和稳定的心输出量，通过上腔静脉的入口流量占心输出量的 40%，而通过右肺动脉 (RPA) 的流量在 30% 到 70% 之间变化，模拟流向肺部的不同血流分布。使用应用于数值数据的控制体积和耗散函数技术来确定功率损耗。在研究的 RPA 流出范围内，使用这些技术计算的损失之间的差异在 3.2% 到 9.9% 之间。这些损失还与之前研究的实验测量结果进行了比较。由于入口流量条件不同，计算出的功率损耗略高于实验结果。尽管需要进行额外的实验研究来确定耗散函数的临床适用性，但人们相信，这种方法与从成像方式（例如磁共振成像）获得的速度梯度信息相结合，可以提供一种评估体内 TCPC 内功率损耗的无创方法。
The total cavopulmonary connection (TCPC) has shown great promise as an effective palliation for single-ventricle congenital heart defects. However, because the procedure results in complete bypass of the right-heart, fluid dynamic power losses may play a vital role in postoperative patient success. Past research has focused on determining power losses using control volume methods. Such methods are not directly applicable clinically without highly invasive pressure measurements. This work proposes the use of the viscous dissipation function as a tool for velocity gradient based estimation of fluid dynamic power loss. To validate this technique, numerical simulations were conducted in a model of the TCPC incorporating a 13.34 mm (one caval diameter) caval offset and a steady cardiac output ofInlet flow through the superiorvena cavawas 40 percent of the cardiac output, while outflow through the right pulmonary artery (RPA) was varied between 30 and 70 percent, simulating different blood flow distributions to the lungs. Power losses were determined using control volume and dissipation function techniques applied to the numerical data. Differences between losses computed using these techniques ranged between 3.2 and 9.9 percent over the range of RPA outflows studied. These losses were also compared with experimental measurements from a previous study. Computed power losses slightly exceeded experimental results due to different inlet flow conditions. Although additional experimental study is necessary to establish the clinical applicability of the dissipation function, it is believed that this method, in conjunction with velocity gradient information derived from imaging modalities such as magnetic resonance imaging, can provide a noninvasive means of assessing power losses within the TCPC in vivo.