The Purkinje fibers originate from which conduction routes?

The Purkinje fibers originate from which conduction routes?

• A. Left and right bundles.
• B. Sinoatrial bundle.
• C. Atrioventricular bundle only.
• D. The fibrous skeleton.

Answer: (A)

Purkinje fibers are the final part of the ventricular conduction system. They originate as the terminal extensions of the left and right bundle branches, which descend from the bundle of His in the AV conduction pathway. From these branches, Purkinje fibers spread through the subendocardial ventricular muscle to rapidly depolarize the ventricles, producing a coordinated, synchronized contraction. They aren’t derived from the SA node or the fibrous skeleton, which mainly serves as insulation and attachment; the SA node initiates impulses, and the AV bundle transmits them to the bundle branches that feed the Purkinje network.

Purkinje fibers are the final part of the ventricular conduction system. They originate as the terminal extensions of the left and right bundle branches, which descend from the bundle of His in the AV conduction pathway. From these branches, Purkinje fibers spread through the subendocardial ventricular muscle to rapidly depolarize the ventricles, producing a coordinated, synchronized contraction. They aren’t derived from the SA node or the fibrous skeleton, which mainly serves as insulation and attachment; the SA node initiates impulses, and the AV bundle transmits them to the bundle branches that feed the Purkinje network.