正常腹主动脉是一根约2．0cm粗的管状大动脉，在动脉硬化、高血压、炎症、吸烟、糖尿病、高血脂、吸毒及艾滋病毒感染等高危因素作用下，腹主动脉壁受侵蚀破坏而变薄弱,在高速高压血流持续冲击下逐渐膨胀而变成球形，遂形成腹主动脉瘤。正象自行车胎局段变薄弱由管状变为球形并 The normal abdominal aorta is a roughly 2.0 cm thick tubular aorta. The abdominal aortic wall is eroded and destroyed by high risk factors such as arteriosclerosis, hypertension, inflammation, smoking, diabetes, high blood lipids, drug use, and HIV infection. The thinning is weak and gradually expands into a spherical shape under the continuous impact of high-speed and high-pressure blood flow, and the fistula forms an abdominal aortic aneurysm. Just as the bicycle segment becomes weaker and weaker from tubular to spherical