目的

对犬左心室内膜浦肯野纤维解剖特征进行大体观察及镜下观察。

方法

选取12只比格犬，年龄（2.90±0.56）岁，其中雄7只，体重（21.50±3.32）kg。采用卢戈氏液对新鲜犬心内膜面染色，大体观察左束支及浦肯野纤维走行，苏木素-伊红染色（HE 染色）、Masson 染色和缝隙连接蛋白40（CX40）免疫组化镜下观察传导束及浦肯野纤维分布。

结果

比格犬12只均成功获取离体心脏，利用卢戈氏液成功显示犬左心室内膜不同级别传导束及浦肯野纤维横向走行特点，并在镜下观察到犬左心室传导系统由多条传导束共同走行于心内膜下层，由结缔组织分割至不同层面。

结论

犬左心室浦肯野纤维呈分级、分层、网络化的分布特征。

Purpose

To guide experiments and catheter ablation for bundle branch or Purkinje-related arrhythmias by anatomical observations of the left ventricular endocardial Purkinje fibers in canines were conducted through macroscopic and microscopic examinations.

Methods

Twelve beagle canines [age (2.90±0.56) years, male for 58.3% (7/12), weight (21.50±3.32) kg] were selected to obtained ex vivo hearts. Lugol's solution was used to stain the endocardial surface of fresh canine hearts for gross observation of the left bundle branch and Purkinje fibers pathways.Histological examination using HE staining, Masson's trichrome staining, and Connexin 40(CX40)immunohistochemistry was performed for microscopic observation of the distribution of bundle branches and Purkinje fibers.

Results

Twelve beagle canines ex vivo heart were successfully obtained, revealing the transverse characteristics of different levels of conduction bundles and Purkinje fibers in the left ventricular endocardium using Lugol's solution, and microscopic observation showed that the conduction system of the left ventricle was composed of multiple conduction bundles that travel together beneath the endocardium, separated into different layers by connective tissues.

Conclusion

The Purkinje fibers in the left ventricle of canines exhibit graded,layered, and networked distribution characteristics, which can guide experimental and ablation treatments for Purkinje-related ventricular arrhythmias.