【作者】 付强；

【导师】 毕研文；

【作者基本信息】 山东大学 ， 外科学， 2006， 博士

【摘要】 研究背景：冠心病的发病率、死亡率均居各种疾病的前列，尤其近年随着我国生活水平的提高，其发病率、死亡率也日渐增高，对于内科规范治疗无效的患者，冠状动脉搭桥术(coronary artery bypass grafting，CABG)是目前最有效的治疗方法，截至2000年我国年CABG例数已发展至5000例左右。CABG的广泛应用使冠心病的治疗得到了突破性发展，手术死亡率已越来越低，病人的生存质量得到了明显提高，美国现每年大约有30万人接受CABG，现有大约200万病人手术后长期存活。数十年临床实践证明，影响CABG术远期效果的重要原因是桥血管闭塞、衰坏。也就是说CABG术后，我们仍要解决一个重要难题：CABG术后桥血管闭塞。 乳房内动脉(internal mammary artery，IMA)因较大隐静脉(great saphenous vein，GSV)长期通畅性高，临床应用日趋增多。目前在国内外，应用左侧乳房内动脉(left internal mammary artery，LIMA)行冠状动脉左前降支(left anterior descending artery，LAD)搭桥已成为第一选择。但临床发现部分患者在术后早期即发生IMA桥血管的闭塞、衰坏，冠脉造影出现“线样征”(string sign)现象。发生“线样征”的机制一直为人们所关注：国外研究报道观点仍有争论，多数研究认为，可能是来自未完全闭塞冠状动脉的竞争血流使IMA血流减少、血流模式变化，导致IMA血管桥痉挛、血栓形成，最终衰坏。但其机理未明，更缺乏临床对策。更多还原

【Abstract】 Objective: To set up new Chinese experimental swinish model of CABG and to study the effects of competitive flow from differently stenotic coronary artery on the flow and the content of endothelin (ET) and nitric oxide (NO) and calcitonin gene-related peptide (CGRP) and atrial natriuretic polypeptide (ANP) in the blood of internal mammary artery (IMA) graft.Methods : Coronary artery bypass grafting (CABG) was conducted in 15 Chinese experimental minipigs using left internal mammary artery(LIMA) anastomosed to left anterior descending artery (LAD) off pump. The proximal LAD was mad differently senotic (0%,30%,50%,75%,90% and 100%) through a flow occluder. When the proximal end of LAD was mad differently stenotic, the mean flow of LAD proximal and distal to the anastomotic stoma and the mean flow and the mode of blood flow and the pulsatility index (PI) value of LIMA were respectively measured through the transit time flow measurement (TTFM) and took blood sample from LIMA graft. The content of ET and NO and CGRP and ANP in the sample of LIMA graft were respectively measured.Results : Chinese experimental minipigs model of CABG were更多还原