In Third Degree Heart Block:
A)the bundle branches are blocked.
B)the SA node and AV node are blocked.
C)some beats are conducted,while others are not.
D)the atria and ventricles are completely dissociated.

Question

Quizplus · Accepted Answer

In Third Degree Heart Block (also known as complete heart block), there is a complete dissociation between the atria and ventricles. This means that the SA node and AV node are completely blocked, and there is no conduction of signals from the atria to the ventricles. As a result, the ventricles will resort to an escape rhythm, which is slower and less efficient than the regular heart rhythm. The bundle branches do not play a direct role in this condition.