Distribution characteristics of Purkinje fibres in the canine left ventricle

Abstract

Purkinje-related ventricular arrhythmias have been increasingly reported, and with the development of catheter ablation techniques, intervention for Purkinje-related arrhythmias has been shown to be effective. The characteristics of Purkinje fibres orientation in the 12 canine left ventricles were observed at a gross level by staining the endocardium with Lugol's solution. Purkinje fibres were observed microscopically by HE, Masson's, PAS glycogen, and Cx40 immunohistochemical staining. Staining was successful, and the transverse orientation characteristics of Purkinje fibres were observed by Lugol's staining, and the longitudinal distribution was observed microscopically. The distribution of Purkinje fibres in the canine left ventricle is 'graded', 'layered', and 'networked', which can guide catheter ablation of Purkinje-related ventricular arrhythmia.

Keywords: anatomy; iodine staining; morphology; purkinje fibres.

FIGURE 1

(A) Canine left ventricular Purkinje fibres follow a graded course in the order of the trunk of the left bundle branch, the LAB and LPB, the network of secondary Purkinje fibres and the endings of the conduction system; (B) The origin of the trunk of left bundle branch from under the valve annulus. LBB, left bundle branch; LAB, left anterior branch; LPB, left posterior branch; FT, false tendon; PM, papillary muscles; MV, mitral valve; VA, valve aortae; CB, connective bundle.

FIGURE 2

(A) Purkinje fibres are layered and interconnected on the endocardial surface; (B) Local magnification of the red rectangular part of (A); (C) Microscopically, Purkinje fibres are seen to be layered on the endocardial surface. ☆: Purkinje fibres along the short‐axis section; →: Purkinje fibres along the long‐axis section.

FIGURE 3

Staining of cross sections of false tendons. (A) PAS glycogen staining, dark blue shows Purkinje fibres running in the false tendons; (B) Cx40 staining, dark brown shows conduction bundles.☆ represents the blood vessels running through the false tendon; the blue‐purple and brown structures indicated by the red arrows are both Purkinje fibres.

FIGURE 4

(A) Purkinje fibres at the junction of the false tendon with the endocardium, which fan out after reaching the papillary muscle; (B) Partial magnification of (A), showing the walking Purkinje fibres on the false tendon, which fan out after reaching the papillary muscle, and the absence of the conduction system on the true tendon. FT, false tendons; TT, true tendons; PM, papillary muscle.