肺动脉闭锁合并室间隔缺损的肺动脉组织病理学改变

目的采用显微镜形态定量分析技术分析肺动脉闭锁合并室间隔缺损和动脉导管未闭患儿的肺血管组织形态学改变,为矫正畸形、选择手术方式提供病理参考指标.方法分别选择同年龄组非心、肺源性疾病死亡患儿,肺动脉闭锁合并室间隔缺损和动脉导管未闭患儿肺组织标本各10例作为对照组和病变组.采用病理学形态定量分析技术,测量肺细小动脉平均中膜厚度百分比(MT%)和中膜面积百分比(MS%)、肺小血管密度(VPSC)、平均肺泡数(MAN)、肺泡平均内衬间隔(MLA)、肺实质占同切片肺总面积比例(PPA)、单位面积肺泡/血管比(AVR).结果病变组的MAN、VPSC和AVR与对照组比较,差异有显著性(P＜0.05),其中病变组的VPSC明显低于对照组(P＜0.001),其余参数差异没有显著性(P＞0.05).病变组肺泡比对照组有增大的趋势,50%的患者MS%接近正常组值.病变组多数肺小血管的形状不规则,肌型动脉相对少见,大部分为部分肌型和非肌型动脉.结论由动脉导管供血的肺动脉闭锁合并室间隔缺损患者的肺肌型动脉密度减少,但肺小动脉中膜厚度和面积百分比与对照组接近.肺动脉闭锁造成的肺血流减少对肺小血管的密度影响最大,而肺小血管数目的减少可直接影响到手术方式的选择和手术效果.肺泡密度减少导致肺泡代偿性增大.肺发育受损是肺功能异常的主要原因.早期手术可增加肺血流,促进肺血管的发育,将有助于肺功能的恢复.

Quantitative Structual Study of Pulmonary Artery in Patients with Pulmonary Atresia with Ventricular Septal Defect

Objective In order to provide pathologic reference for therapeutic rationale, the pathological changes of the pulmonary vasculature in patients with pulmonary atresia with ventricular defect and patent ductus arteriosus were observed by contrast with normal control group. Methods Lung biopsies were taken in the operation in 10 children suffered from pulmonary atresia with ventricular septal defect associated with patent ductus arteriosus(PA group). Autopsy specimens were obtained from 10 children died of non-cardiovascular diseases as normal control group. The tissue was fixed with buffered formalin, routinely prepared by impregnated in wax. Sections were stained by hematoxylin-eosin, Weigert's elastic stain co-unter-stained by van Gieoson's method. Seven parameters were obtained including percentage of media thickness(MT%), percentage of media section area(MS%), numbers of vascular per square centimeter (VPSC), mean alveolar number(MAN), mean linear intercept(MLI), proportion of parenchyma area in total area(PPA), and alveolar/vascular ratio per unit area(AVR)by a computer image processor by quantitative analysis. Results There were significant difference between the two groups in MAN, VPSC, and AVR(P < 0.05). VPSC was significantly lower in PA group than in control group(P < 0.01). Other parameters had no significant difference. The mean alveolar diameter had an increased trend in PA group, although there was no significant difference. MS% of nearly 50% patients was closed to the normal value in PA group. The shape of pulmonary arteriole was irregular. There were few muscular arteries in a field of vision. Conclusions The density of muscular arteries decreases in patients with pu-lmonary atresia with ventricular septal defect and patent ductus arteriosus, but percentage of media thickness and percentage of media section area of pulmonary arterioles are close to the normal value. Diminished flow in pulmonary circulation has a significant effect on numbers of pulmonary arterioles per square centimeter that impact the selection of surgical method and the effect of operation because of the reduction pulmonary arterioles. The decrease of mean alveolar number results in compensatory enlargement of alveolar diameter. The impaired lung development is a major cause of abnormal lung function. Feasible and earlier operation, which can increase pulmonary flow and promote development of pulmonary vascula-ture will be helpful to restore lung function.