犬胸腹主动脉瘤旷置术的血流动力学研究

Hemodynamics of thoracoabdominal aortic aneurysm exclusion of canine models

目的 从血流动力学角度探讨胸腹主动脉瘤 (TAAA)旷置术的适用性及合理性。方法 8条杂种犬 ,依临床改良Hardy术式制作犬胸腹主动脉瘤旷置术模型 ,测量模拟瘤颈上方结扎不同程度时瘤腔内的压力、血流及人工血管内压力的变化。结果 不全结扎时模拟瘤腔内收缩压由术前的 1 99.3mmHg(1mmHg=0 .1 33kPa)降至 82 .9mmHg ,舒张压由 1 53 .4mmHg降至 73 .6mmHg ,脉压差降幅高达 79.7% ;血流量由 79.1ml/min降为 62 .2ml/min ;而人工血管内压结扎后期才逐渐降为 1 0 3 .5mmHg。 结论 本术式在保证脏器、脊髓供血前提下 ,可明显降低胸腹主动脉瘤腔内的最高压力、平均压力、压力波动幅度及血流量 ,因此可有效降低动脉瘤的扩张速度 。

Objective To evaluate the appliance of thoracoabdominal aortic aneurysm exclusion by studying the hemodynamics in the operation of canine models.Methods Eight canine models of thoracoabdominal aortic aneurysm exclusion were made by clinically modified Hardy's operation. When ligating the modelling aneurysm neck at different degrees, the changes in blood pressure, blood flow of modelling aneurysm and mean blood pressure in graft lumen were observed.Results In incomplete ligation, systolic pressure was decreased from 199.3 mm?Hg(1mm Hg=0.133?kPa) to 82.9?mm?Hg and diastolic pressure decreased from 153.4 to 73.6?mm?Hg with the decreased amplitude being 79.7%; Blood flow was decreased from 79.1?ml/min to 62.2?ml/min. However, in graft lumen, mean blood pressure was gradually decreased to 103.5?mm?Hg at the late stage of ligation.Conclusion Under the promise of enough perfusion to spinal cord and viscera, this surgical procedure can decrease the highest blood pressure, mean blood pressure, fluctuation of blood pressure and blood flow in modelling aneurysm greatly. So, it can slow the dilatation and reduce the rupture probability of aortic aneurysm.