Which term refers to the small band of atypical cardiac muscle fibers that receive electrical impulses from the AV node?

• A. bundle of His
• B. cardiac cycle
• C. precordial leads
• D. interval

Answer: (A)

In the heart’s electrical conduction system, a small band of specialized cardiac muscle fibers called the bundle of His carries the impulse from the AV node to the ventricles. This AV bundle sits in the upper part of the interventricular septum and divides into the right and left bundle branches, which distribute the impulse to the ventricles to coordinate their contraction. The other terms don’t describe this conduction pathway—cardiac cycle refers to the sequence of heartbeats, precordial leads are chest ECG sensors, and interval is a measured time on the ECG. The bundle of His best fits the description of the fibers receiving the impulse from the AV node and directing it toward the ventricles.