血管组织重建中人与猪升主动脉、肺动脉干零应力状态的比较(英文)

Comparison of zero-stress state of ascending aorta and pulmonary trunk between human and swine in vascular tissue reconstruction

背景:由于同种心移植器官来源有限,短缺问题日益突出,而猪的心血管系统及血液动力学方面与人类颇相似,猪→人异种心脏移植已成为国内外学者非常重视的课题,其基础研究日趋活跃。目的:比较正常成人与不同月龄猪升主动脉、肺动脉干的零应力状态,为猪→人异种心脏移植吻合血管提供必要的血管组织重建基础。设计:开放性实验。单位:郧阳医学院生物力学实验室。材料:实验于2001-10/2002-09在郧阳医学院医用生物力学实验室完成。人的心脏标本取自无心血管疾病、年龄18～30岁的6例成年男性尸体,均经家属同意。另选取1月龄同种猪42只,分为7组,分别为1,2,3,4,5,6,>6月龄组,每组6只,各组分别于1,2,3,4,5,6,>6月龄时麻醉屠宰。方法:解剖分离相应升主动脉和肺动脉干,用着色笔原位标记各动脉前壁后,将动脉移至氧饱和的Kreb’s液后,沿其轴向均分为5个等长的血管环,再沿径向剪开各血管环,20min后由计算机记录并测量各血管环的零应力状态张开角(张开的血管面内壁中点和内壁两端点连线的夹角)。实验温度为室温20～30℃。所有血管试样的实验操作均在观察对象死后24h内完成。主要观察指标:人与不同月龄猪升主动脉、肺动脉干零应力状态张开角的测定结果。结果:①人与不同月龄猪升主动脉、肺动脉干零应力状态张开角的测定结果比较:人升主动脉的张开角从近侧端的(100.4±12.8)°增至远侧端的(152.8±18.6)°,各月龄猪升主动脉的张开角从近侧端的68°左右增至远侧端的130°左右;人肺动脉干的张开角沿轴向无明显变化,各月龄猪肺动脉干的张开角从近侧端的65°左右增至远侧端的125°左右。人和猪升主动脉、肺动脉干零应力状态张开角比较差异有显著性意义(P=0.028<0.05)。但人升主动脉第2区段和各月龄组猪第4,5区段的张开角相近;肺动脉干各区段与猪肺动脉干近侧端(第1,2区段)的张开角相近。②不同月龄猪升主动脉、肺动脉干零应力状态张开角的测定结果比较:猪升主动脉、肺动脉干的张开角不随年龄增加而发生变化(P=0.063>0.05)。结论:在某些区段人和猪升主动脉、肺动脉干的零应力状态张开角相近,提示猪→人异种心脏移植中相应升主动脉和肺动脉干在某些区段可以相互吻接,而且年龄因素在血管重建过程中的作用并不显著。

BACKGROUND： Due to the source of conspecific heart transplanted organ is limited and it becomes more and more deficient,and porcine cardiovascular system and haemodynamics are very similar to that of human being, therefore, domestic and foreign scholars have paid more attention on the heterogeneic heart transplantation from swine to human, and there are more and more basic studies about it. OBJECTIVE： To compare the zero-stress state of ascending aorta and pulmonary artery trunk between swine of different months and healthy persons, which provides necessary vascular tissue reconstruction basis for anastomosing vessel of heterogeneic heart transplantation from swine to human being. DESIGN： Open experiment. SETTING： Laboratory of Biomechanics, Yunyang Medical College. MATERIALS： This experiment was carried out at the Laboratory of Biomechanics, Yunyang Medical College from October 2001 to September 2002. Human heart specimens were chosen from 6 male adult corpses who had no visible manifestation of cardiovascular diseases, aged 18 to 30 years. Informed consents were obtained from all the relatives. Totally 42 conspecific swine, aged one month, were also chosen and divided into 7 groups, named as 1,2,3,4,5,6 and 〉 6 months groups respectively, with 6 in each group. Swine were anesthetized at 1,2,3,4,5,6,〉 6 months respectively and sacrificed in each group. METHODS： The corresponding ascending aorta and pulmonary artery trunk were dissected and isolated. Each arterial anterior wall was labeled in situ with coloring pen, and then artery was shifted into the oxygen-saturated Kreb＇s solution. Five isometric vascular rings were divided along the axial direction, then each vascular ring was cut open along the radial direction. Opening angle of each vascular ring at zerostress state was measured and recorded by computer 20 minutes later （The included angel formed through connecting the middle point of inner wall of open vascular plane and two end points of inner wall）. The experiment was conducted at room temperature 20-30 ℃. All the procedures of vascular samples were performed within 24 hours after subjects died. MAIN OUTCOME MEASURES： Measuring results of opening angle of ascending aorta and pulmonary trunk at zero-stress state, of swine at different months and human being. RESULTS： ①Comparison of measuring results of opening angle of ascending aorta and pulmonary trunk between swine at different months and human being： Opening angle of ascending aorta of human being increased from （100.4±12.8）°at proximal end to （152.8±18.6）°at distal end. Opening angle of swine at different months increased from about 68°at proximal end to about 130°at distal end; Opening angel of pulmonary artery trunk of human being did not changed significantly along axial direction, and opening angel of pulmonary artery trunk of swine at different months increased from about 65° at proximal end to about 125° at distal end. There was significant difference of opening angle of ascending aorta and pulmonary trunk at zero-stress state between human being and swine （P=0.028 〈 0.05）.But the opening angle of ascending aorta of human being was similar at the second segment to at the fourth and fifth segments of swine of different ages; Opening angle of each segment of pulmonary artery trunk of human being was close to that of proxireal end （first and second segments） of pulmonary artery trunk of swine. ② Comparison of measuring results of ascending aorta and pulmonary artery trunk at zero-stress state of swine at different months： Opening angle of ascending aorta and pulmonary artery trunk of swine did not changed with the increase of age （P=-0.063 〉 0.05 ）. CONCLUSION： Opening angels of ascending aorta and pulmonary artery trunk at zero-stress state are close in some segments between human being and swine, suggesting that corresponding ascending aorta or pulmonary artery trunk can mutually anastomose in some segments in the heterogeneic heart transplantation from swine to human, and the effect of age is not significant in vascular reconstruction.