Which tissue extends from branches of the AV bundle and stimulates ventricular muscle fibers?

Which tissue extends from branches of the AV bundle and stimulates ventricular muscle fibers?

• A. Purkinje fibers
• B. SA node
• C. AV bundle
• D. Bundle of His

Answer: (A)

Purkinje fibers are specialized conducting tissue that extends from the branches of the bundle of His into the ventricular myocardium. They form a subendocardial network and transmit the electrical impulse rapidly to ventricular muscle fibers, causing the ventricles to contract in a coordinated, synchronized way. This rapid delivery is essential for a strong, efficient ventricular beat. The other components have different roles: the SA node sets the heart rate, the AV node provides the delay between atrial and ventricular activation, and the bundle of His carries impulses from the AV node down the interventricular septum, but it is the Purkinje network that actually stimulates the ventricular myocytes.

Purkinje fibers are specialized conducting tissue that extends from the branches of the bundle of His into the ventricular myocardium. They form a subendocardial network and transmit the electrical impulse rapidly to ventricular muscle fibers, causing the ventricles to contract in a coordinated, synchronized way. This rapid delivery is essential for a strong, efficient ventricular beat. The other components have different roles: the SA node sets the heart rate, the AV node provides the delay between atrial and ventricular activation, and the bundle of His carries impulses from the AV node down the interventricular septum, but it is the Purkinje network that actually stimulates the ventricular myocytes.