Question

Which of the following best describes a third-degree AV block in a ventricular rhythm?

Option 1: Complete atrioventricular dissociation
Option 2: Prolonged PR interval
Option 3: Normal electrical conduction
Option 4: Premature ventricular contractions

Answer 1

A third-degree AV block in a ventricular rhythm is characterized by complete atrioventricular dissociation, where there is no correlation between atrial activity (the P wave) and ventricular activity (the QRS complex).

Step-by-step explanation:

A third-degree AV block in a ventricular rhythm is characterized by complete atrioventricular dissociation. This means there is no correlation between atrial activity (the P wave) and ventricular activity (the QRS complex). The impulses initiated by the SA node do not reach the AV node, resulting in an independent rhythm in the ventricles.