【作者】 林多茂；

【导师】 刘国津； 谢进生；

【作者基本信息】 吉林大学 ， 外科学， 2004， 硕士

【摘要】 Bentall手术是治疗主动脉瘤的经典术式，为治疗升主动脉瘤或夹层并主动脉返流开辟了广阔的前景，对于整个升主动脉瘤变或央层的病人，这是唯一根治的方法。但手术中瓣膜置换改变了生理结构及血流动力学，且存在其缺点---机械瓣存在终生抗凝问题，生物瓣存在耐久性问题及二者均存在栓塞、出血、心内膜炎问题等等，使得研究方向趋于保留瓣膜的主动脉根部手术。目前广为流传的有两类保留瓣膜的主动脉根部手术术式：Yacoub的根部成形术和David的根部重建术。近年来心外科对采用何种术式上及各术式的远期效果存在争论，如何根据每个患者的具体情况选择合适的术式、人工血管的大小直径达到最佳最合理的手术效果是心外科医生最为关注的焦点。目前由于无法提供令人信服的基础佐证，使得研究趋向于对主动脉根部进行有限元模型分析，从而得到最接近于正常情况的术式并指导临床。本文第一部分回顾分析1998年3月至2004年1月问在北京安贞医院进行Bentall手术的75例病人资料，探讨主动脉根部置换手术经典术式的适应症、基本方法和手术技术。本文第二部分通过借助影像学及有限元分析软件初步建立主动脉根部有限元模型。 第一部分：目的：探讨主动脉根部置换手术经典术式的适应症、基本方法和手术技术。方法：本组中患者75例，其中急诊手术12例。男性62例，女性13例，年龄23~68岁，平均年龄40．6岁。主动脉根部瘤53例，主动脉夹层4l例，其中DeBakery I型主动脉夹层24例，DeBakery II型主动脉夹层15例，DeBakeryIII主动脉夹层2例。75例均有不同程度的主动脉瓣关闭不全，其中合并二尖瓣关闭不全5例，马方综合征48例，冠心病4例，风心病、动脉导管<WP=71>未闭、升主动脉瘤破裂、房间隔及室间隔缺损各1例。瘤体平均直径6．7±1．4cm(4．4～11．0cm)。经超声心动图(UCG)、计算机断层摄影术(CT)及磁共振成像(MRI)确诊，明确主动脉根部瘤性质、大小、主动脉瓣病变及合并畸形的情况。手术方法：对于主动脉夹层或累及主动脉弓的动脉瘤，采用股动脉插管。以复合带瓣人工血管进行根部置换。结果：75例Bentall手术单纯低温体外循环68例；深低温停循环7例，平均心肌阻断时间129±35．5分钟(43～230分钟)，平均体外循环时间178±50．7分钟(70～300分钟)。75例Bentall手术中死亡3例，死亡率为4．O％，其中1例为马方升主动脉瘤患者，急诊下行Bentall术，术后二次开胸止血，最终死于循环衰竭，1例患者患有风心病，术后无尿，患者家属放弃透析，最终死于肾衰竭，另外1例患者伴有冠心病，于深低温停循环下手术，术后死于心律失常。75例术后早期并发症包括：二次开胸止血7例，心包积液2例，胸腔积液2例，溶血性贫血1例,心律失常5例，胸骨裂开重新固定1例，感染性心内膜炎1例，均已治愈。急性前壁心梗1例，瓣周漏(轻)1例，均采用内科保守治疗，未行手术治疗。2例出现鼻腔出血，与华法令抗凝有关，调整用量后治愈。并发症发生率为24％。手术平均用血量为663．3±415．6ml(0～2000m1)，3例患者手术未输血。50例术后出院前院内超声心动图显示：人工瓣功能良好，人工血管通畅，术前与术后平均左心室舒张末径分别为71．4±11．1mm(50～112mm)和58．9±10．7mm(41．1～90．1mm)。两者间有极显著性差异(P<0．001)。 第二部分：目的：借助影像学及有限元分析软件初步建立主动脉根部有限元模型。方法：离体家猪心脏大血管，做成左心密闭系统，利用MRI成像，测量从0—120mmHg下主动脉根部各水平的直径变化以及主动脉壁的厚度(mm)。将所得的数据输入计算机，利用根据有限元分析软件进行主动脉根部有限元模型的初步建立。结果：采用计算机我们初步建立了主动脉根部有限元模型。 结论： <WP=72> l、 回顾分析1998年3月至2004年1月间在北京安贞医院进行Bentall手术的75例病人资料，根据统计数据得出Bentall手术是治疗主动脉根部病变的一种良好的术式，其治疗效果满意。 2、 精湛的手术技术和麻醉体外循环等整体水平的提高是主动脉根部置换手术取得良好效果的关键。 3、 目前临床上对主动脉瘤的诊断方法有超声心动图、CT及MRI等诊断方法，但超声诊断为最广泛使用的诊断方法。 4、 由于瓣膜置换改变了生理结构及血流动力学，且存在其缺点---机械瓣存在终生抗凝问题，生物瓣存在耐久性问题及二者均存在栓塞、出血、心内膜炎问题等等。因此若瓣膜本身无明显病理改变且瓣环无明显扩张，我们认为可行保留瓣膜的主动脉根部手术，如Yacoub手术或David手术。本组中有18例可行 Yacoub手术或David手术，比例为24．0％。利用MRl成像的方法，获得主动脉根部的影像，初步建立了主动脉根部有限元模型。有限元模型的建立将会为今后的研究及心脏外科的发展提供广阔的空间。更多还原

【Abstract】 Bentall operation is the classical method for the treatment of aorta root aneurysm,and it provide a wide space for the treatment of aorta aneurysm or dissection with aortic insufficiency. But the surgical operation replaced the aortic valve,it changed original physiological construction and blood dynamics, and exist its defects---mechanical valve need anticoagulate and biovalve exist the problem of endurance,and both can cause embolism , haemorrhage and endocarditis,so it make us to study the valve-sparing aortic root replacement. Now there are two kinds of valve-sparing aortic root replacement---remodeling of yacoub and replantation of David. In recent years,there are controversy on which kind of operation to take and the long-term effect of these operations. What the surgeon focus on are how to choose reasonab1e operation and how to choose correct diameter of artificial Dacron graft to get the best results.But there are not enough basic evidence, this make study incline to the aorta root finite-element model analysis,in order to get the most nearing to the normal circumstance and guide clinics.In this article ,part I ,we analyzed seventy-five patients underwent Bentall operation in Beijing Anzhen Hospital from Mar.,1998 to Jan.2004 ,to study the indication ,methods and operative technique of Bentall operation.PartII ,with the aids of MRI and finite-element model analysis soft- ware,to construct finite-element model of the aortic root. Part I :Object :To study the indication ,methods and operative technique <WP=74>of Bentall operation.Methods:Seventy-five patients(62 male and 13 famale)with a mean age of 40.6 years (23~68years) underwent Bentall operation.Aortic root aneurysm 53cases,aortic dissection 41cases, DeBakery I 24cases . DeBakery II15cases, DeBakeryIII 2cases.All patients have different grade of aortic insufficiency, which include mitral valve insufficiency 5 cases ,Marfan syndrome 48cases, coronary artery diseases 4cases, rheumatic heart diseasel cases,PDA l cases, rapture of aortic sinus 1 cases and congenital heart disease lcases.The mean diameter of aneurysm is 6.7±1.4cm(4.4～11.0cm). All the patients were diagnosed by UCG, CT and MRI. In dissecting aortic aneurysm or aortic aneurysm involving aortic arch ,the patients were operated with femoral arterial cannulation. Results:The mean duration of arotic cross-clamping was 129± 35.5minutes (43～230 minutes),and the mean duration of cardiopulmonarybypass was 178±50.7 minutes (70~300 minutes).There were three deaths inhospital,the hospital mortality rate was 4.0%.Postoperative complications include bleeding requiring rethoracotomy 7 cases, arrhythmia 5cases, pericardial effusion 2 cases, thoracic effusion 2 cases, haemolytic anaemia 1 cases,infective endocarditis 1 cases.After operation ,there was 1 patient got acute myocardial infarction, there was 1 patient had low-grade perivalve leakage.2 patients got rhinal hemorrhage , maybe related to improper use of anticoagulant.The mean amount of blood transfusion was 663.3±415.6ml (0～2000ml). Three patients were free from blood transfusion.50 cases with UCG show preoperation and postoperation the diameter of the end phase of left ventricular dilation were 71.4±11.1mm (50～ll2mm) and 58.9±10. 7mm(41.1～90. lmm),there are remarkably statistical discrepancy between them. Part II: Object: To Initial reconstruct finite-element model of the aortic root. <WP=75>Methods:Hearts of pigs with ascending aorta which be made of left ventricle obturator, from MRI ,we can get the diameter of aortic root and aortic wall under different pressure(0～120mmHg). We put this data into computer to reconstruct finite-element model of the aortic root.Results:According to the data we got from MRI ,we can use computer to construct the finite-element model of the aortic root. Conclusion: 1、 We analyzed seventy-five patients underwent Bentall operation in Beijing Anzhen Hospital from Mar.,1998 to Jan.2004,we found Bentall operation is a satisfied operation, 2、 The suitable oper更多还原