人上腔静脉心肌袖的形态学观测

Histological study of the myocardial sleeve of the superior vena cava in human

目的观察人上腔静脉心肌袖的大体解剖及形态特征,为心房颤动(房颤)的临床研究与治疗提供依据。方法20例非心脏原因死亡的尸检标本,取出心脏,置于4％的多聚甲醛溶液中固定1周以上进行取材。取上腔静脉,经酒精脱水,石蜡包埋,分别作纵向和横向连续切片,常规HE染色。选取部分标本进行Masson染色和PGP 9．5单克隆抗体S-P免疫组化染色。结果(1)HE染色结果,上腔静脉壁内有心肌细胞的延伸。(2)Masson染色结果显示,上腔静脉肌袖组织中,纤维结缔组织呈蓝色,心肌细胞、神经纤维和神经节呈棕红色。(3)免疫组化染色结果,上腔静脉的肌袖细胞处存在PGP 9．5免疫组化染色阳性的神经纤维和神经节。结论人上腔静脉壁内有心肌袖的存在,是发生心律失常的结构基础。上腔静脉有丰富的自主神经纤维分布,可能引起肌袖细胞的电生理特征发生改变。

Objective To investigate the anatomic and histological features of superior vena cava （SVC） myocardial sleeve in order to provide basis for the clinical research and the management of atrial fibrillation. Methods The samples were obtained from 20 patients died due to noncardiac causes. The specimens were fixed using 4% formalin. The SVCs were removed and then were dehydrated with ethanol and embedded in paraffin. The specimens were cut along longitudinal and transverse direction and were stained with hematoxylin and eosin （HE）. Selected sections were stained with Masson-Trichrome or with general neural marker protein gene product 9.5 （ PGP 9. 5） according to instruction. Results （ 1 ） The cardiac muscle fibers extended from the atrium into the SVC. （2） Sections stained with Masson-Trichrome showed that the adventitia were blue, the myocardial cells and the nerve fibers and ganglions were red. （3） lmmunolabeling showed that nerve fibers and nerve ganglions distributed in the epicardium of the SVC. Conclusions The myocardium of the right atrial extended into the SVC at varied length may contributed to the substrate of arrhythmia. The abundant autonomic nerves distributed in the venous walls of SVC may have an effect on the electrophysiological characteristics of the cardiomyocytes.