Abstract:

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.

Key words: Purkinje fibers, Anatomy, Iodine staining, Morphology, Ventricular arrhythmias