School of Life Science, Beijing Institute of Technology, Beijing, China.
Department of Vascular and Endovascular Surgery, Chinese PLA General Hospital, Beijing, China.
J Endovasc Ther. 2023 Jun;30(3):441-448. doi: 10.1177/15266028221081089. Epub 2022 Mar 6.
In this study, we aimed to evaluate hemodynamic influence of the dissected aortic system via various ex vivo type B aortic dissection (AD) models.
Twenty-four raw porcine aortas were harvested and randomly divided into 4 groups to create various aortic models. Model A was the control group, while models B to D indicated the AD group, where models B and C presented a proximal primary entry with the false lumen (FL) lengths of 15 and 20 cm, respectively, and model D presented a 20 cm FL with a proximal primary entry and a distal reentry. All the aortic models were connected to a mock circulation loop to attain the realistic flow and pressure status. The flow distribution rate (FDR) of the aortic branches was calculated. Doppler ultrasound was applied to visualize the AD structure and to attain the velocity of flow in both the true and false lumens. Several sections of the AD were stained with hematoxylin and eosin for histologic evaluation after the experiment.
This study demonstrated that higher pressures were found for the AD group compared with the control group. The mean systolic pressures at the inlet of models A to D were 113.34±0.81, 120.58±0.52, 117.76±0.82, and 115.87±0.42 mm Hg, respectively. The FDRs of the celiac artery in models A to D were 8.65%, 8.32%±0.15%, 7.87%±0.13%, and 8.03%±0.21%, respectively. By ultrasound visualization, the velocity of the flow at the entry to the FL in the AD group ranged in 10 to 92 cm/s. The dissection flap presented pulsatile movement, especially in the models B and C which contained 1 primary entry without distal reentries. Histological examinations indicated that AD was located between the intimal and medial layers.
Our ex vivo models demonstrated that the configuration of the dissected aorta influenced the pressure distribution. Moreover, the dissection flap affected the FDR of the aortic branches that possibly inducing malperfusion syndrome.
本研究旨在通过各种离体 B 型主动脉夹层（AD）模型评估夹层主动脉系统的血流动力学影响。
采集 24 个新鲜猪主动脉，随机分为 4 组，建立各种主动脉模型。模型 A 为对照组，模型 B 至 D 为 AD 组，其中模型 B 和 C 分别具有 15cm 和 20cm 的近端原发性入口和假腔（FL），模型 D 具有 20cm 的 FL 和近端原发性入口及远端再入口。所有主动脉模型均与模拟循环回路相连，以获得真实的血流和压力状态。计算主动脉分支的血流分配率（FDR）。多普勒超声用于可视化 AD 结构并获得真腔和假腔中的血流速度。实验后，用苏木精和伊红对 AD 的几个部分进行染色，用于组织学评估。
本研究表明，AD 组的压力高于对照组。模型 A 至 D 的入口平均收缩压分别为 113.34±0.81、120.58±0.52、117.76±0.82 和 115.87±0.42mmHg。模型 A 至 D 的腹腔动脉 FDR 分别为 8.65%、8.32%±0.15%、7.87%±0.13%和 8.03%±0.21%。通过超声可视化，AD 组中进入 FL 的血流速度范围为 10 至 92cm/s。夹层瓣呈现脉动运动，特别是在模型 B 和 C 中，它们没有远端再入口。组织学检查表明 AD 位于内膜和中膜之间。
我们的离体模型表明，夹层主动脉的形态影响压力分布。此外，夹层瓣影响主动脉分支的 FDR，可能导致灌注不良综合征。
