School of Life Science, Beijing Institute of Technology, Beijing, China.
Department of Ultrasound Diagnosis, Chinese PLA General Hospital, Beijing, China.
J Endovasc Ther. 2022 Feb;29(1):132-142. doi: 10.1177/15266028211034863. Epub 2021 Aug 3.
Aortic dissection (AD) is a catastrophic disease with complex hemodynamic conditions, however, understandings regarding its perfusion characteristics were not sufficient. In this study, a mock circulation loop (MCL) that integrated the Windkessel element and patient-specific silicone aortic phantoms was proposed to reproduce the aortic flow environment in vitro.
Patient-specific normal and dissected aortic phantoms with 12 branching vessels were established and embedded into this MCL. Velocities for aortic branches based on 20 healthy volunteers were regarded as the standardized data for flow division. By altering boundary conditions, the proposed MCL could mimic normal resting and left-sided heart failure (LHF) conditions. Flow rates and pressure status of the aortic branches could be quantified by separate sensors.
In normal resting condition, the simulated heart rate and systemic flow rate were 60 bpm and 4.85 L/minute, respectively. For the LHF condition, the systolic and diastolic blood pressures were 75.94±0.77 mmHg and 57.65±0.35 mmHg, respectively. By tuning the vascular compliance and peripheral resistance, the flow distribution ratio (FDR) of each aortic branch was validated by the standardized data in the normal aortic phantom (mean difference 2.4%±1.70%). By comparing between the normal and dissected aortic models under resting condition, our results indicated that the AD model presented higher systolic (117.82±0.60 vs 108.75±2.26 mmHg) and diastolic (72.38±0.58 vs 70.46±2.33 mmHg) pressures, the time-average velocity in the true lumen (TL; 36.95 cm/s) was higher than that in the false lumen (FL; 22.95 cm/s), and the blood transport direction between the TL and FL varied in different re-entries.
The proposed MCL could be applied as a research tool for in vitro hemodynamic analysis of the aorta diseases under various physical conditions.
主动脉夹层（AD）是一种具有复杂血流动力学条件的灾难性疾病，但对其灌注特征的了解还不够充分。在本研究中，提出了一种模拟循环回路（MCL），该回路集成了 Windkessel 元件和患者特异性硅树脂主动脉模型，以在体外再现主动脉血流环境。
建立了具有 12 个分支血管的患者特异性正常和夹层主动脉模型，并将其嵌入该 MCL 中。根据 20 名健康志愿者的速度将主动脉分支的速度视为流量分配的标准化数据。通过改变边界条件，该 MCL 可以模拟正常静息和左侧心力衰竭（LHF）状态。可以通过单独的传感器来量化主动脉分支的流量率和压力状态。
在正常静息状态下，模拟心率和全身流量率分别为 60 bpm 和 4.85 L/min。对于 LHF 状态，收缩压和舒张压分别为 75.94±0.77 mmHg 和 57.65±0.35 mmHg。通过调整血管顺应性和外周阻力，可以通过正常主动脉模型中的标准化数据验证每个主动脉分支的流量分配比（FDR）（平均差异 2.4%±1.70%）。通过在静息状态下比较正常和夹层主动脉模型，我们的结果表明 AD 模型的收缩压（117.82±0.60 比 108.75±2.26 mmHg）和舒张压（72.38±0.58 比 70.46±2.33 mmHg）更高，真腔（TL）中的时均速度（36.95 cm/s）高于假腔（FL）中的时均速度（22.95 cm/s），并且 TL 和 FL 之间的血液传输方向在不同的再入口处有所不同。
所提出的 MCL 可以用作各种物理条件下主动脉疾病体外血流动力学分析的研究工具。
