Final answer:
In third-degree AV node block, there is no correlation between atrial activity and ventricular activity. This leads to a decreased heart rate or pulse.
Step-by-step explanation:
In the case of third-degree AV node block, sometimes referred to as a complete block, no atrial waves can pass through the AV node. This means that there is no correlation between atrial activity (the P wave) and ventricular activity (the QRS complex).
As a result, the ventricles would contract independently of the atria, leading to a decreased heart rate or pulse. The AV node can take over as the pacemaker and initiate contractions at a rate of 40-60 contractions per minute, which is sufficient to maintain consciousness.