What is the conduction velocity of the Purkinje fibers?

What is the conduction velocity of the Purkinje fibers?

• A. 5 m/s
• B. 3 m/s
• C. 1 m/s
• D. 10 m/s

Answer: (A)

Purkinje fibers are built for rapid impulse transmission, delivering the signal quickly through the ventricles so they depolarize almost simultaneously. This fast conduction comes from their large-diameter fibers and abundant gap junctions, which lower axial resistance and allow currents to spread swiftly from cell to cell. As a result, their conduction velocity is among the highest in the heart, typically around 2–4 m/s and can be cited as up to about 5 m/s in some references. Among the options, 5 m/s best reflects this fast speed, faster than ventricular myocardium and far faster than the slow conduction of the AV node.

Purkinje fibers are built for rapid impulse transmission, delivering the signal quickly through the ventricles so they depolarize almost simultaneously. This fast conduction comes from their large-diameter fibers and abundant gap junctions, which lower axial resistance and allow currents to spread swiftly from cell to cell. As a result, their conduction velocity is among the highest in the heart, typically around 2–4 m/s and can be cited as up to about 5 m/s in some references. Among the options, 5 m/s best reflects this fast speed, faster than ventricular myocardium and far faster than the slow conduction of the AV node.