In Third Degree Heart Block with a rate of 40- 60 bpm, with a QRS of less than 0.12 sec., you should suspect that the pacemaker controlling the heart is located in the:
A)SA node.
B)AV junction.
C)ventricles.
D)atria.

Question

Quizplus · Accepted Answer

In third-degree heart block (also known as complete heart block), there is no transmission of electrical impulses between the atria and ventricles. When the heart rate is 40-60 bpm and the QRS complex is less than 0.12 seconds, it suggests that the pacemaker activity is originating from the AV junction. This is because the AV junction can take over pacing duties at a rate of 40-60 bpm, and the narrow QRS complex indicates that the impulse is still traveling through the normal conduction system, which would not be the case if the ventricles were the pacemaker site.

In Third Degree Heart Block with a Rate of 40-