基于体外猪主动脉的多破口B型主动脉夹层模型血流动力学研究  

Changes of hemodynamics in different multi-entry type B aortic dissection models based on ex-vivo porcine aorta

作　　者：员鹏飞 贾贺月 王双静 吴明炜 熊江[1] YUAN Pengfei;JIA Heyue;WANG Shuangjing;WU Mingwei;XIONG Jiang(Department of Vascular and Endovascular Surgery,the First Medical Center,Chinese PLA General Hospital,Beijing 100853,China;Department of Emergency Surgery,the People's Hospital of Peking University,Beijing 100044,China)

机构地区：[1]解放军总医院第一医学中心血管外科,北京100853 [2]北京大学人民医院急诊外科,北京100044

出　　处：《解放军医学院学报》2024年第9期977-983,共7页Academic Journal of Chinese PLA Medical School

基　　金：国家自然科学基金面上项目(82170498);北京市自然基金重点研究专题(Z210012);北京市科技计划项目(Z211100002921048)。

摘　　要：背景目前缺乏从血流动力学角度分析主动脉内膜破口数量对B型主动脉夹层(type B aortic dissection,TBAD)影响的研究。目的 通过构建两破口和三破口的离体猪TBAD模型,分析不同数量破口对TBAD进展的影响。方法 获取成年猪主动脉,处理后使内膜外露,使用特殊刮板分离内膜和中膜形成夹层,控制夹层长度为20 cm,用手术刀在内膜制造不同破口,再次将动脉内外膜位置反转,以此分别构建两破口和三破口TBAD模型。两破口模型为A组:A1两破口直径相同,A2近端破口直径较小,A3远端破口直径较小;三破口模型为B组:B1三个破口直径相同,B2中间破口直径较小,B3支架封堵近端第一破口。模拟循环通路(mock circulation loop,MCL)是由控制系统、脉冲泵、单向阀、储液罐等组成来模仿人体循环的通路。用40%甘油水溶液模拟血液,同时模拟心率为60/min,尼龙颗粒作为超声造影剂。将构建完成的模型与MCL相结合,就可以模拟真实TBAD患者的血流状态。通过多普勒超声测量各破口处的血流动力学参数,得到血流方向改变时间(reflux time,RT)和时间流速积分(velocity-time integral,VTI),描述TBAD破口的血流变化。结果 A1组中,近端破口的血液先流入假腔后流出,以流入为主(VTI:19.39±5.88 vs 9.89±3.41,P=0.013),对于远端破口血液先流出后流入,以流出为主(VTI:22.61±11.81 vs 7.67±3.26,P=0.024)。A2组减小近端破口直径,发现其VTI比值(破口血流方向发生改变后的VTI与整个周期VTI的比值)减小(33.70%±4.22%vs 51.00%±4.80%,P=0.046),远端破口VTI比值无统计学差异。A3组减小远端破口直径,发现其VTI比值减小(30.10%±7.75%vs 15.30%±3.19%,P=0.045),且血流变化时间RT变长[(0.54±0.08) s vs (0.71±0.01) s,P=0.023]。B1组发现,在收缩期血液会通过中间破口从真腔流入假腔,在舒张期血液从假腔流入真腔,其中从假腔流入真腔的血流量占整个心动周期的64.19%±5.30%。近端�Background The number of entry tears impacts the development and prognosis of type B aortic dissection(TBAD).Objective To analyze the influence of different entry tears on the occurrence and progression of TBAD by constructing and comparing flow parameters at each entry in two-entry and three-entry porcine TBAD models,thereby illustrating changes in blood flow direction and volume.Methods Adult porcine aortas were acquired and processed to expose the intima.A special scraper was used to separate the intima and media to create a dissection,with the length of the dissection controlled at 20cm.Subsequently,surgical knives were used to create different tears in the intima.The artery was then flipped again to construct models of TBAD with either two or three entry tears.Among them,the two-entry models were categorized as group A:A1 with two entry tears of the same diameter,A2 with a smaller proximal entry tear,A3 with a smaller distal entry tear;the three-entry models were categorized as group B:B1 with three entry tears of the same size,B2 with a smaller middle entry tear,B3 with the first proximal entry tear sealed by a stent graft.The mock circulation loop(MCL)consisted of a control system,pulsatile pump,one-way valves,and a reservoir tank to mimic the human circulatory system.A 40%glycerol water solution was used to simulate blood,with a simulated heart rate of 60 bpm,and nylon particles served as ultrasound contrast agents.By integrating the completed model with the MCL,it was possible to simulate the blood flow condition of real TBAD patients.The hemodynamic parameters at each breach were measured by Doppler ultrasound,and the blood flow direction change time(RT)and velocity time integral(VTI)were obtained to describe the blood flow changes of TBAD breach.Results In group A1,the blood from the proximal breach flowed into the false lumen first and then flowed out,mainly presented as inflow(VTI:19.39±5.88 vs 9.89±3.41,P=0.013),and for the distal breach,the blood flowed out first and then flowed in,mainly present

关 键 词：B型主动脉夹层 体外模型 模拟循环通路 破口 血流动力学 

分 类 号：R33[医药卫生—人体生理学]