If the AV node is damaged so that it can no longer transmit the signal from the SA node (total heart block), will the ventricles continue to contract? Why or why not?
A) No: there are no cells left to pace and coordinate the heart beat.
B) No: the SA node must be intact to pace the system.
C) Yes: however, ventricular contractions will no longer follow atrial contractions, and the rate of ventricular contractions will be significantly slowed.
D) Yes: the AV bundle will keep the heart going at the usual rate.
Answer: C
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