Si Biao, Qiao Bin, Yang Guang, Zhu Meng, Zhao Fengyu, Wang Tongjian, Li Na, Ji Xiaopeng, Ding Guanghong
Department of Mechanics and Engineering Science, Fudan University, No. 220, Handan Road, Shanghai, China.
Institute of Cardiovascular Disease, General Hospital of Jinan Military Region, Jinan, China.
Cardiovasc Eng Technol. 2018 Jun;9(2):193-201. doi: 10.1007/s13239-018-0341-6. Epub 2018 Jan 22.
The effect of additional pulmonary blood flow (APBF) on the hemodynamics of bilateral bidirectional Glenn (BBDG) connection was marginally discussed in previous studies. This study assessed this effect using patient-specific numerical simulation. A 15-year-old female patient who underwent BBDG was enrolled in this study. Patient-specific anatomy, flow waveforms, and pressure tracings were obtained using computed tomography, Doppler ultrasound technology, and catheterization, respectively. Computational fluid dynamic simulations were performed to assess flow field and derived hemodynamic metrics of the BBDG connection with various APBF. APBF showed noticeable effects on the hemodynamics of the BBDG connection. It suppressed flow mixing in the connection, which resulted in a more antegrade flow structure. Also, as the APBF rate increases, both power loss and reflux in superior venae cavae (SVCs) monotonically increases while the flow ratio of the right to the left pulmonary artery (RPA/LPA) monotonically decreases. However, a non-monotonic relationship was observed between the APBF rate and indexed power loss. A high APBF rate may result in a good flow ratio of RPA/LPA but with the side effect of bad power loss and remarkable reflux in SVCs, and vice versa. A moderate APBF rate could be favourable because it leads to an optimal indexed power loss and achieves the acceptable flow ratio of RPA/LPA without causing severe power loss and reflux in SVCs. These findings suggest that patient-specific numerical simulation should be used to assist clinicians in determining an appropriate APBF rate based on desired outcomes on a patient-specific basis.
以往研究对额外肺血流量（APBF）对双侧双向格林（BBDG）连接血流动力学的影响讨论较少。本研究采用患者特异性数值模拟评估这种影响。一名接受BBDG手术的15岁女性患者纳入本研究。分别使用计算机断层扫描、多普勒超声技术和心导管检查获取患者特异性解剖结构、血流波形和压力曲线。进行计算流体动力学模拟以评估BBDG连接在不同APBF情况下的流场和衍生血流动力学指标。APBF对BBDG连接的血流动力学有显著影响。它抑制了连接中的血流混合，从而形成更顺行的血流结构。此外，随着APBF率增加，上腔静脉（SVC）中的功率损失和反流均单调增加，而右肺动脉与左肺动脉的血流比（RPA/LPA）单调降低。然而，APBF率与指数功率损失之间存在非单调关系。高APBF率可能导致良好的RPA/LPA血流比，但副作用是功率损失不佳和SVC中反流明显，反之亦然。适度的APBF率可能是有利的，因为它会导致最佳的指数功率损失，并实现可接受的RPA/LPA血流比，而不会在SVC中导致严重的功率损失和反流。这些发现表明，应使用患者特异性数值模拟来协助临床医生根据患者特异性预期结果确定合适的APBF率。
